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151 |
Natural Products and Biological Chemistry |
ABS-178 |
Evaluation on Bioactive Compounds of Indonesian Black Tea Using In Silico and In Vitro Methods as Acetylcholinesterase Inhibitors Rosi Nur Azizah*, Ihsanawati
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology
Jalan Ganesha 10, Bandung 40132, Indonesia
*20520030[at]mahasiswa.itb.ac.id
Abstract
Alzheimer (AD) is neurodegenerative disease characterized by accumulation of \beta-amyloid plaque and NFT. Problems associated with AD are expensive to treat, unclear etiology and side effects of treatment. Back to nature is becoming a trend, including in overcoming AD. Black tea is an herbal drink that is rich in bioactive compounds. The aims of this study are to obtain candidates for acetylcholinesterase inhibitors from Indonesian black tea using in silico and in vitro methods and compared its inhibitory power against standard donepezil with low cost and low risk. The stage of this research are (1) identification inhibitory profile of black tea bioactive compounds by molecular docking method, (2) isolation and separation bioactive compounds from Indonesian black tea, (3) inhibition test and (4) structure identification using LC-MS/MS. Based on in silico method, the candidate acetylcholinesterase inhibitors are theaflagallin which has hydrophobic and hydrogen interactions. Based on in vitro method, the best candidates for acetylcholinesterase inhibitors are ITB_TW_2, ITB_TW_6, ITB_TW_8, ITB_TW_15, ITB_TB_1, ITB_TB_7, ITB_TB_8 and ITB_TB_14. LC-MS/MS analysis for ITB_TW_2 and ITB_TB_1 showed the highest abundance was epicatechin. Thus, black tea bioactive compounds have potential as acetylcholinesterase inhibitors and can be used as potential drug candidates to replace donepezil for AD treatment.
Keywords: alzheimer, acetylcholinesterase, acetylcholinesterase inhibitor and Indonesian black tea
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| Corresponding Author (Rosi Nur Azizah)
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152 |
Natural Products and Biological Chemistry |
ABS-179 |
In Vitro Antidiabetic Activity Test and Identification of Active Compounds of the Flower Starfruit Fraction (Averrhoa bilimbi L.) Diana Widiastuti (a*), Siti Warnasih (a), Nurjanah Bella Saputri (a), Wira Eka Putra(b) Supriatno Salam(c), Sustiprijatno (d)
aDepartment of Chemistry, Faculty of Mathematics and Natural Science, Universitas Pakuan, Bogor 16163, Indonesia
bFaculty Department of Biology, Faculty of Mathematics and Natural Science, Universitas Negeri Malang, Jl. Semarang 5, Malang 65145, Indonesia.
cFaculty of Pharmacy, Universitas Mulawarman, Samarinda 75123, Kalimantan Timur, Indonesia.
dResearch Center for Plant Conservation, Botanical Gardens and Forestry, National Research and Innovation Agency (BRIN), Jl. Ir. Juanda Bogor, Indonesia
Abstract
Diabetes Mellitus is a disease caused by metabolic disorders characterized by an increase in blood sugar that exceeds normal. In the category of non-communicable diseases that cause death, diabetes is the third most common disease after cancer and cardiovascular disease. The number of diabetic patients is also expected to continue to increase to reach 578 million people in 2030. Public trust in diabetes prevention can be done by giving antidiabetic agents derived from nature. Belimbing wuluh (Averrhoa bilimbi L.) is one of the plants that can be used as traditional medicine and is commonly found in West Java, with the active compounds it contains, starfruit can be efficacious as an antioxidant, anti-allergic, antibacterial, antidiabetic, antifungal and anti-inflammatory. This study aims to determine the antidiabetic activity of starfruit and identify the active compounds contained in the starfruit. The methods used in this study include the preparation of test samples, extraction, fractionation, antidiabetic test, and identification of active compounds. At the sample extraction stage using the maceration method. The fractionation step was carried out successively from non-polar solvents to polar solvents (n-hexane, ethyl acetate, and n-butanol). The results of the three fractions were continued for in vitro antidiabetic testing through the inhibition of the -glucosidase enzyme. The most active fraction obtained as antidiabetic was then identified as the active compound using LCMS. The results showed that the ethyl acetate fraction of the star fruit flower (Averrhoa bilimbi L.) had the strongest antidiabetic activity in vitro through glucosidase-enzyme inhibition with an IC50 of 52.88 g/mL. The results of identification using the LCMS method obtained some of the most dominant compounds including Lithocholic Acid, Asperulosidic Acid, and Umbelliferone.
Keywords: Flower Starfruit (Averrhoa bilimbi L.), Antidiabetic, α--glucosidase enzyme, LCMS.
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| Corresponding Author (Diana Widiastuti)
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153 |
Natural Products and Biological Chemistry |
ABS-183 |
GREEN TEA EXTRACT (CAMELLIA SINENSIS L.) POTENTIAL TO LIVER OF HYPERURICEMIA RATS (RATTUS NORVEGICUS) FED WITH HIGH PURINE DIET Putranty Widha Nugraheni - Chanif Mahdi - Fitria Rahmawati - Rizki Nur Analita - Lalak Tarbiyatun Nasyin Maleiva
a) Department of Environmental Engineering, University of Tanjungpura
Jl. Prof. Dr. H. Hadari Nawawi, Kota Pontianak, Kalimantan Barat 78124 Indonesia
putranty[at]teknik.untan.ac.id
b) Department of Chemistry, University of Brawijaya
Jl. Veteran, Kota Malang 65145 Indonesia
chanif[at]ub.ac.id
c) Department of Chemistry Education, University of Lambung Mangkurat
Jl. Brigjen Jalan Hasan Basri, Kota Banjarmasin, Kalimantan Selatan 70123 Indonesia
rizki.analita[at]ulm.ac.id
d) Department of Chemistry Engineering, University of Tanjungpura
Jl. Prof. Dr. H. Hadari Nawawi, Kota Pontianak, Kalimantan Barat 78124 Indonesia
putranty[at]teknik.untan.ac.id
Abstract
Uric acid produced in tissues containing xanthine oxidases, like in the small intestine and the liver as purine metabolism of adenine and guanine. High uric acid levels can cause damage to cell membranes due to the lipid peroxidase chain reaction. Foods that contain high purines activate the xanthine oxidase enzyme causing free radicals to increase. Free radicals attack polyunsaturated fatty acids (PUFA) by forming carbon, peroxyl, and lipid peroxidases. PUFA will be broken into simple compounds such as pentane, ethane, and aldehydes, leading to malondialdehyde (MDA) formation. High MDA levels illustrate the process of cell membrane oxidation leading to cell membrane damage. Hyperuricemia is often treated using synthetic drugs such as allopurinol- however, it can cause side effects. Some people will choose medicinal plants with minimal side effects. Green tea (Camellia sinensis L.) contains many polyphenol antioxidants, especially flavonoids, also has a strong antioxidant effect by exerting multiple mechanisms such as inhibiting several enzymes, including antiphospholipid peroxidase, free radical scavengers, metal bonds, and xanthine oxidase (XOD). Statistical analysis results proved that green tea with a dose of 600 mg/kgBW can lower MDA levels of liver by 84.87% (p<0.01), decreased xanthine oxidase (XOD) activity by 35.36% (p<0.01), and improved liver histopathology.
Keywords: Green tea extract, Hyperuricemia, Liver histopathology, Liver malondialdehyde, Xanthine oxidase
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| Corresponding Author (Putranty Widha Nugraheni)
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154 |
Natural Products and Biological Chemistry |
ABS-206 |
Bioactivity Extract of Endophyte Fungi Kalanchoe millotii and Kalanchoe marmorata (Crassulaceae) Heni Rahmawati (a*), Lutfia Silva Aprina (a), Sari Purbaya (a), Yenny Febriani Yun (a*)
a) Department of Chemistry, Faculty of Science and Informatics, Jenderal Ahmad Yani University, Cimahi 40528
*Henirahmawati2804[at]gmail.com, yenny.febriani[at]lecture.unjani.ac.id
Abstract
Cocor bebek (Kalanchoe millotii & Kalanchoe marmorata) have been many used for cope problem health is one potential as antibacterial and antioxidant. Content metabolites Secondary is also found in microorganisms that live in the body network plants, that is endophyte fungi, Study this aim for knowing species mold isolated endophytes, group metabolites secondary extract mold endophyte as well as its potential as antibacterial and antioxidant. Identification result isolate endophyte fungi from root K. marmorata that is Fusarium Sp., root K. millotii that is Fusarium oxysporum and stem K. millotii that is Penicillium citrinum. Extract ethanol and ethyl acetate endophyte fungi obtained with method fermentation and maceration. Phytochemical test results show that extract the contain metabolites secondary group of alkaloids, flavonoids, steroids, triterpenoids, tannins, and quinones. Test activity antibacterial conducted with disk diffusion method, extract ethanol endophyte fungi F. oxyxporum root K. millotii show potency weak antibacterial to Bacillus subtilis, Escherichia coli and Psedomonas aeruginosa and not potential to Staphylocoocus sureus, while extract ethyl acetate endophyte fungi F. oxyxporum K. millotii root have weak ability to B. subtilis, S.aureus and P. aeruginosa and have moderate ability to bacteria E. coli. Test activity antioxidant conducted with DPPH method, extract ethyl acetate Fusarium oxysporum fungi root K. millotii, extract ethanol Fusarium sp fungi root K. marmorata and Penicillium citrinum fungi stem K. millotii show activity antioxidant category no active and moderate with IC50 647.17 ppm, 577.97 ppm , and 231.73 ppm respectively.
Keywords: Antibacterial, Antioxidant, Kalanchoe marmorata, Kalanchoe millotii, Phytochemical.
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| Corresponding Author (Heni Rahmawati)
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155 |
Natural Products and Biological Chemistry |
ABS-211 |
Mouthwash Basil Leaves Essential Oil Hernandi Sujono*, Valentina Adimurti Kusumaningtyas, Rizki Oktafiyani
Department of Chemistry, Faculty of Science and Informatics, Universitas Jenderal Achmad Yani
Abstract
This study aims to formulate essential oil of basil leaves (Ocimum basillicum L.) into mouthwash dosage form and to test its physical stability. Basil essential oil was obtained by using the steam-water distillation method. The method of making mouthwash used is micellar solubilization. Mouthwash was made in five formulas, namely F1, F2, F3, F4 and F5 with a volume of 0.5 mL, 1 mL, 1.5 mL, 2 mL, and 2.5 mL of basil essential oil. Then the physical evaluation includes centrifugation test, organoleptic test, and GC-MS test. The results showed that there were five main compounds in the essential oil of basil leaves, namely citronella, z-citral, cis-3-hexenyl lactate, beta-elemene and bicyclogermacrene. Mouthwash F1, and F2 were stable stored at 27˚-C because after 4 weeks of storage they had the characteristics of light green color, characteristic basil aroma, quite spicy taste and no separation after being tested by centrifugation, in contrast to mouthwash F3, F4, and F5 at At 27˚-C the color changes from light green to turquoise green. Of the five formulas that can be used as mouthwash formulations, F1, with a ratio of essential oils, tween 80 and glycerin = 0.5 mL : 3.75 mL : 1.25 mL. Has a stable characterization during storage with a taste that is not too spicy so it is comfortable when used.
Keywords: Basil leaves- essential oil- mouthwash- Ocimum basillicum L.- steam-water distillation
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| Corresponding Author (Hernandi Sujono)
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156 |
Natural Products and Biological Chemistry |
ABS-214 |
In Silico and in Vivo Sedative-Hypnotic Activity of n-hexane Extract of Keji Beling (Strobilanthes crispa Blume) Leaves Siti Inayah, Gita Novelatika Friatna, Mohamad Rizandi Juliansyah, Bagas Kafabi Julianto, and Lela Lailatul Khumaisah
Fakultas Sains dan Teknologi, Universitas Muhammadiyah Sukabumi
Jalan R. Syamsudin, S.H. No. 50, Cikole, Sukabumi 43113, Indonesia
Abstract
Insomnia is a sleep disorder can cause various health problems. The treatment of insomnia has been done by giving sedative-hypnotic drugs. However, these drugs have dangerous side effects, so other alternatives are needed by searching for new drug candidates from plants. One of the plants that have the potential is keji beling (Strobilanthes crispa Blume). This study aims to determine the potential of keji beling leaves as a candidate for insomnia drug by in silico through molecular docking and in vivo against male white mice. The docking process is carried out on the GABA receptor. The compound of keji beling leave that has the most potential as an insomnia drug candidate is d-limonene. The in vivo method using fireplace test. 15 mice were divided into 5 groups, negative control (aquadest), positive control (diazepam 2 mg/70kgBW), dose 1 (200 mg/kgBW), dose 2 (400 mg/kgBW), and dose 3 (600 mg/kgBW) extract. Keji beling leaves was extracted by maceration technique using hexane. The results showed that the average time the mice left the tube in each treatment were 5, 120, 87, 118, and 123 seconds, respectively. From this study, keji beling leave has the potential as a new drug candidate for insomnia.
Keywords: insomnia, sedative-hypnotic, in silico and in vitro, Strobilanthes crispa Blume, keji beling
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| Corresponding Author (Lela Lailatul Khumaisah)
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157 |
Natural Products and Biological Chemistry |
ABS-215 |
In Silico and in Vivo Anti-inflammatory Activity of Methanol Extract of Cocok Bubu (Elatostema rostratum Blume Hassk) Leaves Fena Nur Afniarty, Dais Mulyana, Anita Anida Harfan, Mila Nurmala Hayati, and Lela Lailatul Khumaisah
Fakultas Sains dan Teknologi, Universitas Muhammadiyah Sukabumi
Jalan R. Syamsudin, S.H. No. 50 Cikole, Sukabumi 43113, West Java, Indonesia
Abstract
Inflammation is a normal protective response to tissue injury caused by physical trauma, chemicals, and microbiological agents. Various drugs have been developed to treat inflammation, such as non-steroidal anti-inflammatory drugs (NSAIDs). However, long-term use of NSAIDs can cause severe side effects. Therefore, using medicinal plant be an alternative inflammatory treatment. One of the plants that has the potential to treat inflammation is cocok bubu (Elatostema rostratum Blume Hassk). The purpose of this study was to determine the effectiveness of methanol extract of cocok bubu leaves as an anti-inflammatory by in silico through molecular docking and in vivo against white male mice through the percentage of inflammation inhibition. Based on a molecular docking, it is known that the compounds of cocok bubu leaves have a good binding to cyclooxygenase-2 (COX-2) receptor with the best effect on phytol acetate and epinephrine. The in vivo method using carrageenan-induced foot edema formation, with edema measurement every 1 hour for 6 hours. The results showed that the extract doses of 200, 400, and 600 mg/kg BW had anti-inflammatory activity with inflammation inhibition percent 60.00, 70.67, and 87.25%. The most effective dose is 600 mg/kgBW because the percentage of inflammation inhibition better than a positive control.
Keywords: cocok bubu, Elatostema rostratum Blume Hassk, anti-inflammatory, in silico and in vitro, molecular docking
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| Corresponding Author (Lela Lailatul Khumaisah)
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158 |
Natural Products and Biological Chemistry |
ABS-222 |
A Review on Ethnopharmachy and Pharmacology of Kepok Banana Peels (Musa paradisiaca Formatypica) Asman Sadino (a*), Faizah Min Fadhlillah (a), Riza Apriani (b), Dhea Siti Hajar (a)
a) Department of Pharmacy, Universitas Garut
Jalan Jati No. 42 B, Garut, Indonesia
*asman[at]uniga.ac.id
b) Department of Chemistry, Universitas Garut
Jalan Jati No. 42 B, Garut, Indonesia
Abstract
Banana (Musa spp.) is a fruit plant grown in tropical and sub-tropical areas. Bananas can be widely used by Indonesian people and have a high economic value. One type of banana that is widely used is kepok banana (Musa paradisiaca Formatypica). However, the use of bananas so far is only the fruit, while banana peels are generally thrown away as organic waste. The utilization of the kepok banana peel is still not optimal, even though the banana peel contains several secondary metabolites with pharmacological activities. Based on the results, it was found that kepok banana peels have been used as traditional medicine in several ethnic groups in Indonesia, such as Dondo, Kaili, Mori, Sasak, and Banggai. Some of its pharmacological activities are antidiarrheal, anti-inflammatory, wound healing, burn healing and anti-acne. Meanwhile, the use of kepok banana peels is only carried out by the Sasak Tribe and Sri Kuncoro Village. From existing ethnopharmaceutical data, the Sasak Tribe, Lombok Regency, West Nusa Tenggara Province uses kepok banana peels to treat sprains. The presence of secondary metabolites such as alkaloids, flavonoids, tannins and saponins is thought to play a role in various pharmacological activities produced in overcoming various diseases.
Keywords: Ethnopharmacy- Pharmacology activity- banana peel- Musa paradisiaca
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| Corresponding Author (Riza Apriani)
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159 |
Organic Synthesis and Medicinal Chemistry |
ABS-61 |
CANCER DRUGS AND 99mTc-GLUTATHIONE RADIOPHARMACEUTICAL INTERACTION TO ACHIEVE OPTIMAL RESULT OF CANCER DIAGNOSTICS IN NUCLEAR MEDICINE Teguh Hafiz A Wibawa, Ahmad Kurniawan, Isti Daruwati, Iswahyudi
Badan Riset dan Inovasi Nasional (BRIN)
Abstract
Cancer is one of the leading causes of death in the world, including Indonesia. The application of nuclear techniques in nuclear medicine plays an important role in diagnosing cancer and identify an optimal therapy. BRIN has contributed to the development of diagnostic kits, one of which is 99mTc-Glutathione. Utilizing these diagnostic kits, there is a tendency to increase the risk of drug interactions consumed by cancer patients with diagnostic kits that can lead to misinterpretation of data. This study aims to investigate the possible alteration in the pharmacokinetics profiles and biodistribution of 99mTc-Glutathione when given in combination with cancer drugs in Balb/C strain mice (Mus musculus). The study was divided into four groups of normal and model animals test. Each group is differentiated by treatment, i.e. control (I), animals test with doxorubicin treatment (II), 5-fluorouracil (III), and methotrexate (IV). Each drug is intravenously, after 5 minutes it is injected with 99mTc-Glutathione intravenously. Furthermore, the pharmacokinetics and biodistribution studies were carried out. Study of pharmacokinetics and biodistribution interaction showed that the administration of cancer drugs before administration of 99mTc-Glutathione reduces the elimination half-life and target / non-target organ ratio significantly. The target / non-target ratio of 99mTc-Glutathione (control) and 99mTc-Glutathione that combined with cancer drugs doxorubicin, 5-fluorouracil, and methotrexate in normal mices are:7.01, 1.47, 1.43, and 5.61 respectively. Whereas, the target/non-target ratio of 99mTc-Glutathione (control) and 99mTc-Glutathione that combined with cancer drugs doxorubicin, 5-fluorouracil, and methotrexate in cancer model mices are: 2.94, 1.33, 0.42, and 2.11 respectively. The results can certainly cause misinterpretation of diagnosis data. Therefore, the phenomenon of drugs and radiopharmaceutical interactions must be considered by clinicians in nuclear medicine.
Keywords: drugs interaction, cancer, diagnostic kits, 99mTc-Glutathione
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| Corresponding Author (Teguh Hafiz Ambar Wibawa)
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160 |
Organic Synthesis and Medicinal Chemistry |
ABS-62 |
Preparation and Physico-chemical characterization of 99mTc-Deoxyglucose as a candidate radiopharmaceutical for diagnostic imaging of cancer Teguh Hafiz A Wibawa, Eva Maria Widyasari, Maula Eka Sriyani, Isa Mahendra, Ahmad Kurniawan, Yanuar Setiadi, M. Basit Febrian, Iim Halimah, Hendris Wongso
Badan Riset dan Inovasi Nasional
Abstract
Cancer is a genetic disease that causes by mutations in DNA from a normal cell to a cancer cell. The cancer cell grows quickly and spread to other parts of the body, this condition became the leading cause of death. One of the detection methods that are currently used to detect tumors and metastatic tissues is conducted with radiopharmaceutical of (18F) fluoro 2 deoxy 2 D glucose (18F FDG). This method is quite accurate but is relatively expensive because it needs PET / CT camera that is still limited in Indonesia. With these limitations, in previous studies was developed 99mTc DTPA deoxy D glucose (99mTc DTPA DG) radiopharmaceutical that application using a gamma camera. As new radiopharmaceuticals, the physical and chemical characteristics of these compounds must be known. In this study, physicochemical characterization tests were determined are radiochemical purity, electric charge, lipophilicity (log P), and plasma protein binding. The study result determines that 99mTc DTPA DG radiopharmaceuticals have high radiochemical purity (95.28 0.87%), neutral electric charge, the lipophilic value (log P) minus 1.24 and the plasma protein binding was 72.09 1.65%. The 99mTc-DTPA-DG radiopharmaceuticals liquid kit that storage up to 60 days in minus 20 oC or additional volumes of technetium 99m up to 3 mL still gives radiochemical purity above 95%. From this study, the physicochemical characteristics data of the radiopharmaceutical 99mTc DTPA DG were obtained which can be used in further in vivo studies. From in vivo studies will obtain comprehensive information about the bioactivity of these compounds for cancer diagnostics.
Keywords: 99mTc DTPA DG, 2 deoxy D glucose, physicochemical, radiopharmaceutical, cancer
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| Corresponding Author (Teguh Hafiz Ambar Wibawa)
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161 |
Organic Synthesis and Medicinal Chemistry |
ABS-66 |
BROMINATION OF EUGENOL DERIVATIVES WITH MOLECULAR BROMINE Budi Arifin (1*), Yana Maolana Syah (1), and Didin Mujahidin (1)
1) Chemistry Study Program, Bandung Institute of Technology
Jalan Ganesha 10, Bandung 40132, Indonesia
*budiarifin2[at]gmail.com
Abstract
Eugenol (4-allyl-2-methoxyphenol) conducts aromatic bromination at C-6 with molecular bromine (Br2), whereas eugenyl benzoate and methyleugenol undergo aromatic bromination at C-5, both preceded by alkene bromination. There is no information yet on the exact composition of bromination products generated from eugenol derivatives employing various Br2 equivalents and phenol protecting groups. Therefore, we present the bromination of eugenol derivatives (eugenyl acetate, eugenyl benzoate, and benzyleugenol) with 1.2, 2.4, and 3.6 equivalents Br2 in chloroform. Bromination with 1.2 equivalents Br2 produces dibromide as an adduct of an alkene double bond in all three derivatives. This is followed by aromatic substitution at C-5 to produce 5-bromo dibromide derivatives with 2.4 equivalent Br2. The dibromide and 5-bromo dibromide derivatives of eugenyl acetate are hydrolyzed promptly during aromatic substitution and undergo additional substitution. As a result, the main products are 5-bromoeugenol dibromide and 6-bromoeugenol dibromide. The brominated acetate esters are no longer evident when 3.6 equivalents Br2 are applied. The benzyl ether begins to cleave as well, but the benzoyl ester is not, implying that this group is more acid resistant. These findings suggest that by utilizing the benzoyl protecting group, a strategy for indirectly substituting the eugenol ring at C-5 could be devised.
Keywords: Benzyleugenol- Dibromide- Eugenyl acetate- Eugenyl benzoate
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162 |
Organic Synthesis and Medicinal Chemistry |
ABS-73 |
Synthesis of Fused-Ring Systems and Diarylmethane Isoflavanones via Ortho-Quinone Methide Intermediates Vidia Afina Nuraini (a*), David StC Black (b), Naresh Kumar (b)
a) Study Program of Chemistry, Department of Chemistry Education, Universitas Pendidikan Indonesia, Jalan Dr. Setiabudhi 229, Bandung 40154, Indonesia
*v.nuraini[at]upi.edu
b) School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
Abstract
Flavonoids, the most commonly studied phytoestrogens, are natural compounds distributed in plants and have been part of the human diet. Among the various classes of flavonoids, isoflavanones have gained significant interest due to their promising biological activities, including anti-cancer and anti-inflammatory. However, flavonoids suffer from low bioavailability, limiting their overall utility for therapeutic applications. To overcome this limitation, we modified the structure of isoflavanone, dihydrodaidzein, via a highly reactive ortho-quinone methide (o-QM) intermediate generated in situ from a Mannich base. In this study, we investigated the behaviour of o-QM in an inverse electron-demand Diels Alder (iEDDA) reaction with electron-rich dienophiles, resulting in fused-ring systems. In addition, we explored the Michael-type addition to an o-QM with various nucleophiles, providing access to diarylmethane products. A total of 10 novel dihydrodaidzein analogues were successfully synthesized. The cycloaddition and Michael addition reactions proceeded in a highly regioselective way, depending on the charge distribution of the reacting partners. Overall, electron-rich dienophiles or nucleophiles gave products in higher yields, while electron-poor ones remained unreactive.
Keywords: Isoflavanone, Dihydrodaidzein, Ortho-quinone methide, Mannich base, Inverse electron-demand Diels Alder reaction, Michael addition
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| Corresponding Author (Vidia Afina Nuraini)
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163 |
Organic Synthesis and Medicinal Chemistry |
ABS-77 |
GREEN SURFACTANT: SURFACTANT SYNTHESIS USING STRECKER MODIFICATION TECHNIQUES AND SURFACTANT FORMULATION FOR CHEMICAL ENHANCED OIL RECOVERY (CEOR) APPLICATIONS Ilham Ardatul Putra (a), Yani F. Alli (a), Yohanes B.D. Wangge(a), Didin Mujahidin(b)
(a) Research and Development Center for Oil and Gas Technology ^LEMIGAS^
Jl. Ciledug Raya Kav.109, Cipulir, Kebayoran Lama, Jakarta Selatan 12230, Indonesia
(b) Organic Synthesis Laboratory, Bandung Institute of Technology
Jl. Ganesha No. 10, Lebak Siliwangi, Coblong, Bandung 40132, Indonesia
Email: ilham937[at]gmail.com
Abstract
Despite the continuing development of sustainable sources of energy, crude oil and natural gas resources remain crucial elements of the international economy. With global petroleum and liquid fuel demand continually increasing, improving the efficiency of extraction from existing natural reserves of petroleum is of utmost importance as the world gradually transitions away from fossil fuels toward more sustainable sources. Toward that end, enhanced oil recovery (EOR) techniques have been developed and are used to minimize the amount of crude oil and petroleum that is left behind in underground reservoirs from conventional drilling extraction methods. In this study, surfactants were synthesized using a fatty acid derived from palm oil as a hydrophobic group and sulfonat as a hydrophilic group.
The use of vegetable oil as the raw material is likely due to its abundance and environmentally friendly. Sulfonation of anionic surfactant was performed by utilizing the Strecker modification technique in which an alkali metal bisulfite (versus sulfite) is used to sulfonate the epoxide group. The preferred sulfonating reagent is a mixture of sodium BIsulphite and sodium sulfite (1:1,1- 1:2- 1:3) as well as various time reactions. Product surfactant was characterized by thin-layer chromatography (TLC) to determine the optimum condition and reaction conversion. The molecular structure of surfactant was confirmed by 1H NMR. Nonionic surfactant was then analyzed by measuring the interfacial tension (IFT) of oil and water, wettability, and imbibition test.
The results showed that the optimum conditions to obtain the hight convertion were achieved by reacting oleil glisidil ether and Natrium Sulfit-Bisulfit at an equivalent mole ratio of 1: 2 and 21 hours reaction time. Oleil Glisidil Eter Sulfonat surfactant was able to decrease the IFT of oil and water as 10-2 dyne/cm in brine salinity condition of 18000 ppm and oil 34,39 OAPI. This study also formulated surfactants OGES and OG
Keywords: Surfactant Anionic, SurfactanNonionic, Enhanced Oil Recovery
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| Corresponding Author (Ilham Ardatul Putra)
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164 |
Organic Synthesis and Medicinal Chemistry |
ABS-100 |
ANTIFUNGAL AND WOUND HEALING ACTIVITIES OF CHITOSAN NANOPARTICLES FROM GREEN MUSSEL SHELL AND JERNANG ETHANOL EXTRACT DRESSING PATCH Arkhi Roslia Yuvie(1), Novi Nuraeni(1*), Putu Reza Sandhya Pratama(1), Danisha Herianti(1), Valentina Adimurti Kusumaningtyas(1), Jasmansyah(1)
1. Department of Chemistry, Faculty of Science and Informatics, Universitas Jenderal Achmad Yani,
Jalan Terusan Jenderal Sudirman, Cimahi 40513, INDONESIA
*corresponding email: novinuraeni01[at]yahoo.com
Abstract
The development of chitosan nanoparticles and jernang (Daemonorops draco) as wound medicine materials have received a lot of attention from researchers. In this research the two materials will be combined. The antifungal of the materials determined based on inhibition test of Candida albicans and Malassezia furfur. The wound healing activities determined based on the in vivo wound healing test on Wistar rat (Rattus novergicus). The materials applicated on wound dressing patch. Chitosan was sinthesized from green mussels shell waste (Perna viridis L). The result showed that the yield of chitosan is 64.67% and degree of deacetylation (DD) was 69.53%. Meanwhile, chitosan nanoparticles can be prepared based on ball mill process. The result showed that average of the particles size is 437.6 nm (nanoparticles size is 1-1000 nm). Jernang was obtained by maseration process using ethanol organic solvents technical. The yield is 22.41% and showed positively of alkaloid, saponin, flavonoid and triterpenoid test. F3 has highest activies on antifungal and wound healing test results.
Keywords: wound healing, dressing patch, chitosan, green mussel shell (Perna viridis), jernang (Daemonorops draco)
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| Corresponding Author (Novi Nuraeni)
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165 |
Organic Synthesis and Medicinal Chemistry |
ABS-106 |
CHARACTERISTICS AND ANTIOXIDANT ACTIVITY OF NANOPARTICLES CHITOSAN ROSELLE (HIBISCUS SABDARIFFA) Retno Diyah Utari (1*) - Budi Saputra (1) - Randi Kristiana (1) - Tiani Yunita (1) - Jasmansyah (1) - Valentina Adimurti K (1)
1. Department of Chemistry, Faculty of Science and Informatics, Universitas Jenderal Achmad Yani
Jalan Jenderal Sudirman, Cimahi 40513, West Java, Indonesia
*Corresponding email : retnodiyahu[at]gmail.com
Abstract
Roselle (Hibiscus sabdariffa) contains flavonoids with antioxidant activity. The present study aimed to examine the characteristics and antioxidant activity index (AAI) of roselle extract (RE) after being modified into nanoparticles chitosan of roselle (NCR). Phytochemical screening indicated that roselle extract contains flavonoids, saponins, tannins and steroid/triterpenoids compounds. The NCR was prepared using a bottom-to-up method from a cross-link reaction between chitosan and tripolyphosphate. The ratio of RE:Chitosan:Tripolyphosphate was 2:1:0.1. NCR characterization showed 464.6 nm of a particle size, 0.849 of a polydispersion index and -6.0 mV of a zeta potential. Antioxidant activity was measured by utilizing the DPPH method (2,2-diphenyl-1-picrylhydrazyl), with a UV-Vis spectrophotometer at a wavelength of 515 nm. IC50 data were analyzed using the One Way Annova test with a confidence level of 95%. Results showed that NCR had an IC50 value of 22.577 ppm (AAI:2.217), which is classified as a very strong antioxidant. The IC50 value of the RE was 77.610 ppm (AAI:0.644), which is categorized as a moderate antioxidant. The results of this study reveal that the modification of roselle extract (RE) into nanoparticles chitosan of roselle (NCR) was proven to enhance the AAI (p<0.05).
Keywords: Rosella - antioxidant - nanoparticles
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| Corresponding Author (Retno Diyah Utari)
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166 |
Organic Synthesis and Medicinal Chemistry |
ABS-107 |
Fluorescence Enhancement of Bodipy by Pah via PET Annihiliation Dikhi Firmansyah1,*, Niken Roro Hapsari1,2, Monica Christania Damanik1,2, Muhammad Yudhistira Azis2,*
1 Organic Chemistry Division, Bandung Institute of Technology, Jalan Ganesha 10, Bandung, 40132, Indonesia.
2 Analytical Chemistry Research Group, Bandung Institute of Technology, Jalan Ganesha 10, Bandung, 40132, Indonesia.
*Corresponding author, 1email: dikhfi[at]itb.ac.id, 2email: yudhistira[at]itb.ac.id
Abstract
Boron-dipyrromethene (BODIPY) is an excellent candidate for sensor and colorimetric probes due to its stability, high molar absorption coefficient, excellent fluorescence quantum yield, easy functionalization, and better compatibility for a biological system. Weak interaction of PAHs hydrogen and strained meso-aryl BODIPY is reported. In this work, we focused our study on the interaction of unstrained meso-aryl BODIPY to selected PAHs (naphthalene, phenanthrene, and anthracene). Isosbestic absorption points were obtained on PAHs addition with BODIPYs. However, fluorescence enhancement of BODIPYs by anthracene was negligible unless the alkoxy group was present. The resulting weak interaction, presumably unable to alter the rotation of meso phenyl and para-toluene BODIPY, but able to reduce PET (photoinduced electron transfer) phenomena on alkoxy-perfluorophenyl BODIPY. To our benefit, the fluorescence intensity is linear to PAH concentration. These results indicate that alkoxy-meso-aryl BODYPY could be a potential candidate for the PAH sensor through the fluorescence enhancement process.
Keywords: BODIPY- PAH- PET- Sensor- Colorimetry
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| Corresponding Author (Dikhi Firmansyah)
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167 |
Organic Synthesis and Medicinal Chemistry |
ABS-160 |
Effect of Water on Fructone Synthesis from Ethyl Acetoacetate Asep Kadarohman1,*, Iim Ismaya1, Sopi Alawiah1, Ratnaningsih E. Sardjono1, Amelinda Pratiwi1, Vidia Afina1, and LL Khumaisah2
1 Department of Chemistry Education, Faculty of Mathematics and Science Education, Universitas Pendidikan Indonesia, Jalan Dr. Setiabudhi No. 229 Bandung 40154, Indonesia
2 Department of Chemistry, Faculty of Science and Technology, Universitas Muhammadiyah Sukabumi, Jalan R. Syamsudin, S.H. No. 50 Sukabumi 43113 Indonesia
* Email: kadar[at]upi.edu
Abstract
The reaction of the synthesis of fructone (Ethyl 2-methyl-1,3-dioxolan-2-acetate) from ethyl acetoacetate with an acid catalyst produces 2-methyl-2-(ethoxycarbonylmethyl)-1,3-dioxolane and triethylene glycol diacetate as side products. This research aims to study the effect of water on increasing the amount of fructone produced and reducing the amount of side products. Fructone synthesis reaction uses a reflux system with azeotrope technique equipped by Dean Stark to attract water with cyclohexane as a solvent. Fructone synthesis reaction was carried out at a mole ratio of ethyl acetoacetate and ethylene glycol 1:2 with sulfuric acid and para toluene sulfonic acid as catalysts at temperature of 78 oC, 80 oC, and 82 oC. To determine the effect of water, a fructone synthesis reaction was carried out without using the azeotrope technique and the azeotrope technique with variations in the amount of cyclohexane 20 mL, 30 mL, and 40 mL. The reaction products were analyzed by GC and GCMS. It was found that reducing the amount of water in the reaction system increased the amount of fructone produced. The addition of cyclohexane as an azeotrope reduces the number of side products. The amount of fructone produced in the use of sulfuric acid and para toluene sulfonic acid catalysts is almost the same. In the fructone synthesis reaction at 80 oC, 40 mL cyclohexane, 2 hours reaction time, and 0.006 moles H2SO4 catalyst, 95.66% fructone was produced, the remaining unreacted ethyl acetoacetate was 3.24% and the by-product was 1.1%.
Keywords: Synthesis, fructone, water
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| Corresponding Author (Asep Kadarohman)
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168 |
Organic Synthesis and Medicinal Chemistry |
ABS-184 |
Xanthorrhizol and its derivatives as the inhibitors of caspase-7 Yunita Purnamasari, Nizar Happyana, Yana Maolana Syah*
Department of Chemistry, Bandung Institute of Technology
Abstract
Xanthorrhizol (1) is a bisabolene sesquiterpene found as the main terpenoid constituent of the Curcuma xanthorrhiza rhizomes. The compound is reported to having a range of biological activities, including as anti-estrogenic, anti-estrogenic, anti-inflammatory, antioxidant, anti-hyperglycemic, nephroprotective, and hepatoprotective properties. Although the biological properties of 1 has a low selectivity, this fact showed that 1 has the potential as a bioactive molecule. To increase its selectivity, as well as to be more potent its biological properties, we had synthesize six derivatives of 1 using a number of chemical reactions, including nitration (followed by nitro reduction) and substitution reactions. The nitration reaction resulted two isomer ic nitroderivatives, namely 2-nitroxanthorrhizol (2) and 4-nitroxanthorrhizol (3). Reducing of 2 by acetic acid yielded 2-aminoxanthorrhizol (4). In the substitution reaction of the phenolic-OH group afforded 4-(3-(2-methyl-5-(6-methylhept-5-en-2-yl)phenoxy)propyl)morpholine (5), 6,7-dimethoxy-3-(3-(2-methyl-5-(6-methyilhept-5-en-2-yl)phenoxy)propyl)quinazoline-4(3H)-on (6), and N-benzyl-3-(2-methyl-5-(6-methylhept-5-en-2-yl)phenoxy)propane-1-amine (7). The structures of these derivatives were determined analyzing their NMR and mass spectral data. Compounds 1-6 were tested for their capacity to inhibit caspase-7, the enzyme that responsible for a diverse physiological and cell-damaging stressors and delaying the onset of apoptosis. The results showed that only 2 and 3 that can weakly inhibit the enzyme activity (~ 15% inhibition). In conclusion, six derivatives had been synthesized from xanthorrhizol (1), which only the derivatives 2 and 3 that showed inhibition to the caspase-7.
Keywords: Synthesis, Xanthorrhizol, Cancer, Caspase-7
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| Corresponding Author (Yunita Purnamasari)
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169 |
Physical & Theoretical Chemistry |
ABS-13 |
Potential of Nanocellulose Acetate as Surfactant for Water-Vegetable Oil Systems Ikhsan Ibrahim, Mia Ledyastuti
Bandung Institute of Technology
Bandung Institute of Technology
Abstract
Indonesia, as an agricultural country, has a variety of abundant plants. This makes the topic of research on the use of plant waste in the form of biomass more interesting. Resizing cellulose to nanocellulose and modification of nanocellulose to nanocellulose acetate can increase its potential as a surfactant. Resizing cellulose can be done using the strong acid hydrolysis method. Modification using acetic anhydride reagent was carried out to convert the surface hydroxy functional group into acetyl. The successful production of nanocellulose was confirmed using FTIR and PSA characterization. The results of the infrared absorption spectrum of cellulose and nanocellulose showed no difference in peaks. Particle size distribution results for CNC I and CNC II showed nanocellulose has sizes 142 nm and 319 nm, respectively. The interfacial tension of water-vegetable oil systems through experiment and simulation has a similar trend. The value of interfacial tension gets smaller with the addition of nanocellulose acetate compared to the addition of nanocellulose. With the agreement between the experimental and computational results, nanocellulose acetate can act as a surfactant.
Keywords: Nanocellulose, nanocelulose acetate, surfactant, computational
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| Corresponding Author (Ikhsan Ibrahim)
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170 |
Physical & Theoretical Chemistry |
ABS-40 |
The Effect of Geometry Bond in Orbital d (Co and Ni) Biosorption with Ligands Using Activated Seaweed Bioadsorbent Neny Rasnyanti M Aras(a*), Agus Salim (a), Hatifa (a)
Community College of Manufacture Industry Bantaeng
Abstract
One of the preliminary efforts to deal with the problem of waste containing heavy metals is to use biomass as an adsorbent. Bioadsorbents are widely used because of their ability to adsorb metals through the chemical bonds. The aim of this research is to make bioadsorbent from acid activated Euchemma Cottonii seaweed then it contacted with Co and Ni metals. The tests carried out included testing the levels of heavy metals Co and Ni using Inductively Coupled Plasma (ICP) and FTIR. From the results of this study, it was found that the contribution of the bond formed between the metal and the bioadsorbent affects the capacity and optimum time for metal absorbed by the bioadsorbent, which has been never revealed correlation both of them. Co has a larger metal adsorption capacity (161 mg/g) with optimum time of 150 minutes while Ni has an adsorption capacity of 91 mg/g with with optimum time of 90 minutes. The mechanism of metal absorption by bioadsorbents was confirmed by shifting functional groups through FTIR that occurred between bioadsorbents before and after contact with metals mainly in-OH, S=O, C=O, C-O-C, -NH the active groups.
Keywords: Bioadosorbent, activated seaweed, geometric bond, orbital d
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| Corresponding Author (Neny Rasnyanti M Aras)
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171 |
Physical & Theoretical Chemistry |
ABS-90 |
DESIGN NEW POTENT BETULIN DERIVATIVES AS ANTICANCER AGENT USING MULTIPLE LINEAR REGRESSION AND ARTIFICIAL NEURAL NETWORK METHODS Uripto Trisno Santoso1,*, Muhammad Khafi2, Samsul Hadi2, Bayu Bakti Angga Santoso3
1Department of Chemistry, Faculty of Mathematics and Natural Sciences, University of Lambung Mangkurat, Jl. A. Yani Km 36 Banjarbaru, South Kalimantan INDONESIA
2Department of Pharmacy, Faculty of Mathematics and Natural Sciences, University of Lambung Mangkurat, Jl. A. Yani Km 36 Banjarbaru, South Kalimantan INDONESIA
3Master Program in Pharmaceutical Sciences, Faculty of Pharmacy, Gadjah Mada University, Jl. Sekip Utara, Sleman, Yogyakarta 55281, INDONESIA
*Corresponding author, tel/HP: +6285868736288, email: utsantoso[at]ulm.ac.id
Abstract
Betulin, betulinic acid, and its natural and synthetic derivatives act specifically on cancer cells with low cytotoxicity towards normal cells. The purpose of this study is to establish a multiple linear regression (MLR) model for design new potent betulin derivatives indicating high activity against HT29 human colon cancer cells, and the artificial neural network (ANN) method was used for model refinement. Topological descriptors properties were calculated using Mordred Descriptor web. Microsoft Excel for Microsoft 365 (Version 2206) integrated with XLstat version 24.3.1 (Addinsoft) and equipped with XLSSTAT R() function was used to MLR and ANN modelling. The ANN models were developed using a RProp+ algorithm with the number of input layers were varied from 2 to 7 and hidden layers 2 to 10. The final MLR model yield a fit to the training set data (R2 = 0.910, R2adj = 0.877) and shown to perform well in internal and external validations.
Y = -5.043-0.257(SlogP)-3.62x10E11(SM1D)-0.039(ATSC1i)
+18.808(Xc6dv)+0.127(ATSC4p)+1.205(GATS7c)
Interestingly, model refinement using an ANN applying the same descriptors generated better models, but it has lowered the predictive power. Furthermore, the MLR and ANN models have a significantly different in prediction the structures of the new potent betulin derivatives.
Keywords: Multiple Linear Regression, Artificial Neural Network, Betulin, Cancer, Descriptor, Quantitative Structure-Activity Relationship (QSAR).
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| Corresponding Author (Uripto Trisno Santoso)
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172 |
Physical & Theoretical Chemistry |
ABS-187 |
Simulations of Water Adsorption and Dissociation on Cubic Yttria (110) Aulia Sukma Hutama, Lala Adetia Marlina, Widya Purnamasari, Karna Wijaya
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Bulaksumur, Yogyakarta 55281, Indonesia
Abstract
A study on the interaction of water on the surface of \(\alpha\)-Y\(_2\)O\(_3\) (110) has been carried out based on molecular dynamics simulations using the SCC-DFTB method. The purpose of this study is to determine the interactions that occur in the \(\alpha\)-Y\(_2\)O\(_3\) (110)-H\(_2\)O structure and the structure formed upon molecular dynamics simulation. In this study, structural modeling was conducted for \(\alpha\)-Y\(_2\)O\(_3\) and \(\alpha\)-Y\(_2\)O\(_3\) (110). The molecular dynamics simulation of \(\alpha\)-Y\(_2\)O\(_3\) (110)-H\(_2\)O was carried out for 120 ps at a temperature of 298.15 K. The algorithm used was the Velocity Verlet algorithm with the Nose-Hoover thermostat temperature control. The \(\alpha\)-Y\(_2\)O\(_3\) (110) surface was reactive to the presence of water molecules. Water molecules were adsorbed on the surface \(\alpha\)-Y\(_2\)O\(_3\) (110) through the Y-OH\(_2\) bonding. Some of the Y-OH\(_2\) dissociated to form Y-OH\(^-\), and >OH\(^+\). Molecular dynamics simulation with SCC-DFTB can be used to study the interactions between water molecules and the \(\alpha\)-Y\(_2\)O\(_3\) (110) surface.
Keywords: SCC-DFTB, MD
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| Corresponding Author (Aulia Sukma Hutama)
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173 |
Polymer Chemistry & Bio-based Materials |
ABS-21 |
Formulation and In-vitro Characterization of Bacterial cellulose-Nanoparticles Loaded with Mg(OH)2 and Ag Henry F. Aritonang*, Shintya Maryani, Gillby Laseduw, Audy D. Wuntu
Physical Chemistry Division, Faculty of Mathematics and Natural Sciences, Sam Ratulangi University
Abstract
Bacterial cellulose (BC) is a type of natural cellulose widely synthesized by Acetobacter xylinum. However, BC itself does not have antibacterial properties that are important for any particular purpose. Therefore, some researchers insert materials that are antibacterial in BC. The objectives of this study were to develop bacterial cellulose (BC)-nanoparticles (NPs) loaded with Mg(OH)2 and silver (Ag) and to determine the composition of magnesium nitrate hexahydrate (MN) and silver nitrate (SN) precursors showing the best antibacterial properties. SNs of different contents (1, 3, 5, 7, and 9% of the mass of MN) were inserted with MN (5 g) into BC. This synthesis used the co-precipitation method by immersing BC into the two precursor solutions in an alkaline environment. The deposition of Mg(OH)2 and Ag NPs in the BC fibers was confirmed by a change in the color of the BC membrane from white to brownish. The profiles of Mg(OH)2 and Ag NPs deposited on BC fibers were relatively different. Mg(OH)2 particles tended to agglomerate and cover the fiber, while Ag particles also agglomerate but not as much as Mg(OH)2 particles. The composition of 9% SN produced BC/Mg(OH)2/Ag-9% material that had higher Mg(OH)2 and Ag NPs content and smaller size. In addition, BC/Mg(OH)2/Ag-9% was better at inhibiting the growth of E.coli and S.aureus.
Keywords: Formulation- Bacterial cellulose, Nanoparticle- Mg(OH)2- Ag- Antimicrobial
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| Corresponding Author (Henry F. Aritonang)
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174 |
Polymer Chemistry & Bio-based Materials |
ABS-33 |
Utilization of Acetic Acid as Anti Bacterial Agent of Starch-Based Bioplastic Rossy Choerun Nissa (a*), Anti K. Fikriyyah (a), Rizka (b), Oceu D. Putri (a), Bonita Firdiana (a), Myrtha Karina (a), Akbar H. D. Abdullah (a)
a) Research Center for Biomass and Bioproducts, National Research and Innovation Agency, Cibinong 16911, Indonesia
b) Departement of Chemistry, Universitas Tanjungpura, Pontianak 78124, Indonesia
Abstract
The growth of microorganism on a natural polymer based material is inevitable. Acetic acid as one of food grade anti bacterial agents can be used to resist microorganism growth on bioplastics. This study aimed to investigate the anti bacterial activity of acetic acid on starch based bioplastics and its biodegradability. Starch based bioplastics were fabricated by mixing starch and glycerol (3:1, w/w) with acetic acid at concentration of 0.25- 0.5- 0.75- 1.00% (w/w). Bioplastics were prepared through a series of processes: (1) blending of starch and glycerol for 3 min, (2) extruding of the starch glycerol mixture by using single screw extruder at 80 until 130C, (3) compression molding of 150C and 50 kgf /cm2. Escherichia coli has been used for determining the resistance of bioplastics against the microorganism by disc diffusion method. Aspergillus niger was used to assess the biodegradability of bioplastics and were carried out for 7 days. Futhermore, biodegradability of bioplastics was slightly decreased which indicated that the addition of acetic acid did not significantly affect the biodegradation. Based on these results, the addition of acetic acid as an anti bacterial agent can be used to prevent bioplastics from microorganism which is potentially for food packaging application
Keywords: Bioplastics- Starch- Acetic acid- Anti bacterial- Biodegradability
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| Corresponding Author (Rossy Choerun Nissa)
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175 |
Polymer Chemistry & Bio-based Materials |
ABS-67 |
The Effect of Sulfur Ratio To MBTS Accelerator on Viscoelastic, Vibration Damping, and Thermal Stability Properties of Unfilled Natural Rubber Vulcanizates Adi Cifriadi(a,b), Purwantiningsih Sugita(a*), Tetty Kemala(a), Siti Nikmatin(c)
(a)Department of Chemistry, Faculty of Mathematics and Natural Sciences, IPB University, Bogor 16680, Indonesia
(b)Indonesian Rubber Research Institute, Palembang, Indonesia
(c)Department of Physic, Faculty of Mathematics and Natural Sciences, IPB University, Bogor 16680, Indonesia
Abstract
It is well-recognized that the sulfur ratio to accelerator has greatly influenced the properties of rubber vulcanizates. Viscoelasticity, vibration damping, and thermal stability are important properties of rubber vulcanizates as isolators for automotive applications. The isolator standard are indicated high values of damping factor, viscous modulus, thermal stability, and low values of elastic modulus. This research aims to study the effect of the ratio between sulfur to 2-2^-dithiobenzothiazole (MBTS) accelerator on viscoelastic, vibration damping, and thermal stability properties of unfilled natural rubber (NR) vulcanizates. This ratio was specified respectively at 0.11- 0.22- 1.11- 2.15 and correlates with the efficient, semi-efficient, or conventional types of sulfur vulcanization of rubber vulcanizate. Study of the viscoelastic and vibration damping properties were determined by rubber process analyser (RPA) at frequency variation from 0.08 - 50 Hz at a temperature of 90oC with a fixed strain of 0.5o, and the thermal stability was investigated by thermogravimetric analysis (TGA). The results showed that the semi-efficient type of sulfur vulcanization of unfilled NR vulcanizates containing sulfur ratio to MBTS accelerator at 1.11 had the best of viscoelastic (elastic and viscous modulus) and vibration damping properties (tangent delta) as a rubber isolator. However, in terms of thermal stability properties, the conventional sulfur vulcanization of unfilled NR vulcanizates containing sulfur ratio to MBTS accelerator at 2.15 was the excellent among others. Base on the isolator standard, the semi-efficient type of the sulfur vulcanization of unfilled NR vulcanizates containing sulfur ratio to MBTS accelerator at 1.11 was preferably, but its thermal stability properties need to be increased.
Keywords: rubber, sulfur, viscoelastic, vibration damping, thermal stability
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| Corresponding Author (Purwantiningsih Sugita)
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176 |
Polymer Chemistry & Bio-based Materials |
ABS-82 |
Determination of the Mathematical Equation of Intrinsic Viscosity as the Function of Melt Flow Rate on Polypropylene Block Copolymer Asep Fahrudin, Jasmansyah, Anceu Murniati, Hernandi Sujono, and Arie Hardian*
Department of Chemistry, Faculty of Sciences and Informatics, Universitas Jenderal Achmad Yani, Cimahi, West Java, Indonesia.
E-mail: arie.hardian[at]lecture.unjani.ac.id
Abstract
Melt Flow Rate (MFR) analysis is commonly performed to determine polymer quality, is a relatively simple test and does not require a solvent. MFR value is the main parameter to be reported which is inversely related to the molecular weight of the polymer. Intrinsic Viscosity (IV) analysis also needs to be carried out to characterize the molecular weight of polymer where the IV value is directly proportional to the molecular weight. IV analysis is a long-time analysis, requires solvents and is generally carried out automatically using complex instruments. The research purpose is to determine an equation that correlates MFR and IV values of polypropylene block copolymer so that IV value can be obtained and reported more quickly and efficiently through the calculation of the MFR value. The equation that correlates MFR and IV values was studied and obtained by performing MFR and IV measurements simultaneously on a population of polypropylene block copolymer powder samples with various specifications. A comparison of MFR and IV values shows that the relationship model is inversely proportional to the power equation as follows: IV = 2.5257 (MFR)^-0.209 with a coefficient of determination R2 = 0.964. IV value can be obtained through calculation from the result of MFR analysis.
Keywords: MFR, IV, Correlation, Polypropylene block copolymer, Molecular weight
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| Corresponding Author (Asep Fahrudin)
|
177 |
Polymer Chemistry & Bio-based Materials |
ABS-86 |
Analysis of Corrotion Rate and Hardness in Low Carbon Steel Coated With Electrodepositionally Shynthesized PAni-TiO2 Composite Material Eka Sulistyaningsih, Nidia Lestari, Muhammad Yusuf
Institut Sains & Teknologi AKPRIND
Abstract
In the industrial world, the use of carbon steel has been widely used. Corrosion of carbon steel is something that cannot be avoided, so many studies have been carried out to overcome corrosion. One of the efforts to overcome corrosion is by coating. In this study, low carbon steel coating was carried out by combining TiO2 and polyaniline (PAni) which was carried out by electrodeposition. Carbon steel plate that has been coated is corroded by immersing it in an acid and salt medium. After corrosion, the plate is tested for hardness. The plate without inhibitor has a hardness value of 131 kg/mm2, while the plate with the highest hardness value is a plate coated with PAni 10-1 M and TiO2 10-4 M at 336 kg/mm2. Based on visual observation, the corrosion that occurs is uniform corrosion.
Keywords: Carbon steel, corrsion rate, electrodeposition, hardness
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| Corresponding Author (Eka Sulistyaningsih)
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178 |
Polymer Chemistry & Bio-based Materials |
ABS-91 |
Synthesis, characterization and application of chitosan - metal oxides nanoparticles in water treatment: a review Qurratu Aini Alya Adzkia(a), Mita Nurhayati(a), Fitri Khoerunnisa(a)*
(a)Department of Chemistry, Indonesia University of Education, Setiabudi 229 Bandung, Indonesia, 40154
Abstract
Chitosan has attracted substantial attention in biomedicine and nanomaterials fields because of its excellent properties, such as biocompatibility, biodegradability, non-toxicity, and antimicrobial properties. Recently, the synthesis of chitosan nanoparticles has received great attention due to its nanometer size and large surface area that will exert substantial and new modification to its properties (high reactivity, improved mechanical properties, etc.) which are crucial for advanced applications. Modification of chitosan nanoparticle with metal oxides can extend its application in various fields. This review highlights the recent advances on synthesis methods and characteristic of chitosan-metal oxides nanoparticles systematically. In addition, the application of chitosan-metal oxides nanoparticle in water treatment as adsorbent, antibacterial agent, and photocatalyst are discussed comprehensively.
Keywords: Chitosan, metal oxides, nanoparticles, synthesis, anti-bacterial
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| Corresponding Author (Fitri Khoerunnisa)
|
179 |
Polymer Chemistry & Bio-based Materials |
ABS-99 |
Cellulose-based Phase Change Materials for fever compress Raudhatul Fadhilah(*a), Doddy Irawan(b)
(a) Departement of Chemistry, Universitas Muhammadiyah Pontianak
*raudhatul.fadhilah[at]unmuhpnk.ac.id
(b) Departement of Mechanical Engineering, Universitas Muhammadiyah Pontianak
Abstract
Cases of death due to fever that is not handled properly increases every year. Fever is an early indicator of the body being infected, so that early intervention for fever needs to be done so that the body does not convulse due to significant changes in heat. So far, people have used instant fever-reducing compresses for initial treatment. Instant compresses can absorb heat from the body up to 3 ˚-C. Instant compresses circulating in the market are imported goods made of hydrogel and have the disadvantage of being used only once. Therefore, it is necessary to develop a heat-reducing compress that can be used repeatedly with local material sources. The purpose of this study was to produce a medical device in the form of a fever compress. In this research, phase change material (PCM) will be synthesized by cellulose capsulation method. The cellulose used comes from banana peel waste. Banana peel is a waste generated from processing bananas with the amount of skin produced is 2.09 million tons per year. The high waste generated has great prospects for processing into cellulose. This research is an experimental study with a central composite design with variations in cellulose weight, cellulose shape, and paraffin weight. As a comparison, used instant compresses on the market.
Keywords: cellulose- compress- fever- phase change material
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| Corresponding Author (Raudhatul Fadhilah)
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180 |
Polymer Chemistry & Bio-based Materials |
ABS-105 |
Antiinflammation Drug Released Material Based on Chitosan/ Poly(Vinylpyrrolidone)/ Sodium Diclofenac Hydrogel Composites: Synthesis and Characterization Yustika Desti Yolanda(a), Mita Nurhayati(a,b), Eli Hendrik Sanjaya(c), Murni Handayani(d), Fitri Khoerunnisa(a)*
(a) Graduate Program of Chemistry, Indonesia University of Education Setiabudi 229 Bandung 40154 Indonesia
(b) Department of Advanced Science and Technology Convergence, Kyungpook National University, Sangju-si, Gyeongsangbuk-do, South Korea
(c) Chemistry Department, Universitas Negeri Malang, 65145, Indonesia
(d) Research Center for Advanced Materials - National Research and Innovation Agency (BRIN), Kawasan Puspiptek, Tangerang Selatan, Banten, 15314, Indonesia
Abstract
Development of drug-controlled release material for biomedical applications has been carried out. This study aims to synthesis and characterization of chitosan/ poly (vinyl pyrrolidone)/sodium diclofenac-based hydrogel composites for antiinflammation drug delivery materials. The hydrogel composites were synthesized via solution mixing of polymer precursor solution with an aid of glutaraldehyde as crosslinker at room temperature. The composition ratio of each precursor and crosslinker was optimized systematically. In particular, the sodium diclofenac composition in hydrogel composite matrix was varied in order to investigated the drug release behavior in hydrogel composite. The synthesized hydrogel composites were characterized using several methods, i.e. FTIR spectroscopy, SEM-EDX, X-ray diffraction, TG/DTA, porosity, contact angle, swelling mechanical strength, and antibacterial tests. The results show that FTIR spectra confirmed the interaction of polymer precursors, crosslinker and drug compound that predominantly occurred via hydrogen bonding as indicated by typical absorption peaks at 3435 cm-1, 1650 cm-1, 1290 cm-1, and 600-800 cm-1. The SEM images at cross-section demonstrated the pore formation in hydrogel matrix as a result of crosslinker addition that well mixed with the polymeric matrix, indicating the three-dimensional network of hydrogel composites. Moreover, the swelling ratio, water contact angle and porosity of hydrogel composites were 3500%, 72.36 degree, 98.44%, respectively, that was obtained at optimum composition of polymeric precursors and crosslinker. These results inferred that the synthesized hydrogel composite has a hydrophilic nature and porous structure, consequently, demonstrated the large water absorption capacity as represented by huge swelling ratio. It also indicated that this composite has great potential as superabsorbent for drug release application. The other characterization results are still in progress.
Keywords: Hydrogel composites, Chitosan/PVP/sodium diclofenac, Antiinflammation, Synthesis, Characterization
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| Corresponding Author (Fitri Khoerunnisa)
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