Endang Astuti
Department Of Chemistry, Faculty Of Mathematics And Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281

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ENCAPSULATION OF HORSERADISH PEROXIDASE-GLUCOSE OXIDASE (HRP-GOx) IN SILICA AQUAGEL SYNTHESIZED FROM RICE HULL ASH FOR ENZYMATIC REACTION OF GLUCOSE Nuryono Nuryono; Narsito Narsito; Endang Astuti
Indonesian Journal of Chemistry Vol 8, No 2 (2008)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (261.556 KB) | DOI: 10.22146/ijc.21619

Abstract

In recent years, the sol-gel technique has attracted increasing interest as a unique approach to immobilize biomolecules for bioanalytical applications as well as biochemical and biophysical studies. In this research, encapsulation of Horseradish peroxidase-Glucose oxidase (HRP-GOx) enzymes in silica aquagel from rice hull ash by sol-gel process has been carried out. In addition, the effect of several parameters (weight ratio of HRP to GOx, pH, temperature, sodium ion concentration) on enzyme activity was studied, as well. Rice hull ash, which was produced by ashing at 700 °C, was extracted it's silika by NaOH solution 1 M at 100 °C for two hours to produce sodium silikate (Na2SiO3) solution. The Na2SiO3 solution with pH of 13 was added with a strong cation exchanger resin, to produce sol solution with the pH of 4. Encapsulation was emphasized by mixing sol solution and phosphate buffer pH 7 containing HRP-GOx solution at volume ratio of buffer to sol solution 1:5. The mixture was transferred into 96-microwell plate and was aged for 24 hours. Enzymatic reaction was carried out by adding chromogenic solution of phenol and 4-aminoantipyrine (4-AAP) and b-D-glucose solution (as substrate) into the microwell. Enzymatic activity was examined by measuring absorbance of product solution at 490 nm with ELISA reader. Result of enzymatic activity for encapsulated enzymes (SGE) was compared to that for free enzymes (EB). Results showed that at the investigated condition, HRP-GOx enzymes gave high activity at weight ratio of HRP to GOx 10:1 and pH 7 for both SGE and EB. Encapsulation caused the enzymes activity decrease to 53.0±0.2 %. However, SGE was observed to be more stable on pH and temperature changes than EB. Study on the effect of sodium concentration showed that the increase of sodium concentration from 0.10 to 0.37 M decreased the enzymatic activity to 56±0.2%. Reusability test showed that the synthesized SGE was reusable with activity decrease of 60% within 23 days.
CYTOTOXICITY OF Phaleria macrocarpa (Scheff.) Boerl. FRUIT MEAT AND SEED ETHANOL EXTRACT TO MONONUCLEAR PERIFER NORMAL CELL OF HUMAN BODY Endang Astuti; Deni Pranowo; Santi Dwi Puspitasari
Indonesian Journal of Chemistry Vol 6, No 2 (2006)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (367.076 KB) | DOI: 10.22146/ijc.21763

Abstract

There were many research on Phaleria macrocarpa (Scheff.) Boerl. fruit for its activity as possible anticancer. However, there wasn't investigation that P. macrocarpa seed and fruit meat ethanol extract effect to normal cell. The research was conducted to identify the ethanol extract of P. macrocarpa for cytotoxic activity against mononuclear perifer normal cell of human blood. The research comprised several sections including P. macrocarpa seed and fruit meat maceration with ethanol, and the cytotoxic activity test against mononuclear normal cell. The results showed that the ethanol extract of P. macrocarpa fruit meat and seed was slightly toxic against mononuclear normal cell with the LC50 of 3817.54 μg/mL and 1349.29 μg/mL respectively. Tamoxifen and 5-fluorourasil, anticancer drugs were extremely toxic against mononuclear normal cell giving LC50 of 3.52 μg/mL and 4.05 μg/mL. The ANOVA f-test (P<0,05) showed that seed of ethanol has higher cytotoxic activity than fruit meat extract. Extract no cytotoxic activity difference between tamoxifen and 5-fluorourasil.
CYTOTOXIC EFFECTS OF PROTEIN FRACTION ISOLATED FROM Curcuma mangga VAL RHIZOMES AND CONTAINING RIBOSOME-INACTIVATING PROTEINS ON CANCER CELL-LINES AND NORMAL CELL Sismindari Sismindari; Retno S. Sudibyo; Endang Astuti
Indonesian Journal of Chemistry Vol 4, No 3 (2004)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (291.497 KB) | DOI: 10.22146/ijc.21855

Abstract

C. mangga Val. has been used as an alternative remedy for cancer in Yogyakarta. The protein fraction of C. mangga was identified to contain Ribosome-inactivating Protein which cleave supercoiled double stranded DNA in vitro. In this experiment, the protein fraction isolated from fresh, 400C dried and freeze dried C. mangga Val. rhizome was screened against HeLa, Raji cell-lines and normal mononuklear cells for cytotoxic effects. This would enable us to describe the sensitivity of the protein extract on different cell types. The level of cytotoxicity was determined on the level of LC50 which was based on the percentage of the cell death following the 24 hours incubation with the extract.The protein isolated from C. mangga Val. was able to cleave supercoiled double stranded DNA to nick circular form. This result suggested that protein contained RIPs. The highest activity was identified in the protein isolated from fresh C. mangga Val, and this was followed respectively by freeze drying and 400C drying C. mangga Val. The comparison of the cytotoxic effect showed that protein of fresh C. mangga Val produced the largest number of death cells and the most toxic was on the HeLa cell line. Moreover, the LC50 indicated that the highest cytotoxic effect was shown by protein isolated from fresh C. mangga Val. followed respectively by freeze drying and 400C drying C. mangga Val. Based on LC50, the highest cytotoxic effect of C. mangga Val was found on HeLa cell line, while similar cytotoxic effect was appear on Raji cell line and normal mononuclear cells
CYTOTOXICITY IDENTIFICATION OF THE SUPERNATANT OF Manihot esculenta Crantz RHIZOME AS RIBOSOME-INACTIVATING PROTEIN TO NORMAL CELL Endang Astuti; Sabirin Matsjeh; Winarto Haryadi; Deni Pranowo; Nuning Sri Mulatsih
Indonesian Journal of Chemistry Vol 4, No 2 (2004)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (186.72 KB) | DOI: 10.22146/ijc.21857

Abstract

The supernatant of Manihot esculenta Crantz rhizome has been used as an alternative remedy of infectious and cancer in Jogjakarta. Cytotoxicity assay showed that  Manihot esculenta Crantz supernatant had cytotoxic effect to cancer cell line, namely Myeloma (LC50 = 180,24 μg/mL) and HeLa (LC50 = 415,55 μg/mL), but have a little cytotoxic effect to SiHa. This research was aimed to identify cytotoxic activity of Manihot esculenta Crantz's supernatant to normal cell, particularly to human mononuclear cell and Vero cell line, and to compare to the cancer cell lines. The result showed that supernatant of M. esculenta had cytotoxic effect to normal mononuclear cell (LC50 = 564,00 μg/mL) and Vero cell line (LC50 = 686,00 μg/mL). The supernatant of M. esculenta had the highest cytotoxic activity to myeloma and relatively toxic to cervix cancer HeLa and normal cell, but less to SiHa.
EXTRACTION OF PALM OIL’S FREE FATTY ACIDS BY TRIETHYLAMMINE (TEA) IN POLAR-NONPOLAR MIX-SOLVENT Endang Astuti; Winarto Haryadi; Sabirin Matsjeh
Indonesian Journal of Chemistry Vol 2, No 1 (2002)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (66.586 KB) | DOI: 10.22146/ijc.21932

Abstract

Palm oil contains unsaturated fatty acids that can be oxidated and can make rancidity of the palm oil. One of the trigliserida degradation products is free fatty acid. The usage of triethylammine (TEA) in the polar-nonpolar mix solvents could enhance the free fatty acids extraction efficiency. Free fatty acids extraction from palm oil was carried out for a minute with solvents ratio: TEA 0,00-0,20M in the following solvent: 0-99% diethyl ether + 99-0% ethanol + 1% water, % volume. The extraction was also performed in the following solvent: TEA 0,00-0,20M in 0-95% heptane + 95-0% isopropanol + 5% water, % volume. Reextraction was conducted for a minute by adding Na2SO4 1M. The alcohol layer which was rich with free fatty acid was taken out and the acid value was determined. As comparison, palm oil's free fatty acids was taken out with standard method by refluxing the sample in 95% alcohol for ten minutes. Identification of the free fatty acids was done by Gas Chromatography-Mass Spectrometer. The best solvent ratio for acid value determination was TEA 0,10-0,20M in the mix-solvent: 19% diethyl ether + 80% ethanol + 1% water, % volume and the extraction product contained 8 kind of free fatty acids. In addition, TEA 0,01M in the solvent: 95% isopropanol + 5% water, % volume could be obtained 8 kind of free fatty acids too. In contrary, the free fatty acid extraction by standard method contained 7 kind of fatty acids. Linoleic acid was the free fatty acid which could not be taken out by standard method. The usage of TEA in the proper polar-non polar mix-solvent was the complete method to determine free fatty acid contained in the palm oil.
Three Dimensional Structural Modelling of Lipase Encoding Gene from Soil Bacterium Alcaligenes sp. JG3 Using Automated Protein Homology Analysis Dilin Rahayu Nataningtyas; Tri Joko Raharjo; Endang Astuti
Indonesian Journal of Chemistry Vol 19, No 3 (2019)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (14.741 KB) | DOI: 10.22146/ijc.34152

Abstract

Bacterial lipases have significant potential to be used as the biocatalyst for many chemical reactions. In this study, a novel gene encoding lipase was isolated from an Alcaligenes sp. JG3. A pair of designed primer has successfully isolated 1 kb (LipJG3) that shares 98% identity towards lipase from Alcaligenes faecalis during sequence analysis. By using in silico tools, LipJG3 was related to the transporter protein sequences. Three highly conserved regions consisting of EASGSKT, VILLD, and LSGGQQQRVAIA were found. These regions were known as ATP-binding signature at Walker-A and Walker-B motifs and the S signature of ABC transporter family respectively. In addition, the 3-D structure of LipJG3 has been suggested but the role of the catalytic triad residues have been not fully understood.
Synthesis, Molecular Docking, and Evaluation of Some New Curcumin Analogs as Antimalarial Agents Endang Astuti; Tri Joko Raharjo; Putra Boang Manalu; Ilham Satria Putra; Stephanus Satria Waskitha; Junita Solin
Indonesian Journal of Chemistry Vol 21, No 2 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.57646

Abstract

This research involves the synthesis, antimalarial evaluation, and molecular docking of several curcumin analogs. A total of six curcumin analog compounds were synthesized using aldol condensation using hydrochloric acid and sodium hydroxide catalysts. The synthesized compounds were elucidated using FTIR, 1H-NMR, 13C-NMR, and LC-MS/MS. Subsequently, all curcumin analogs were tested as an antimalarial agent against Plasmodium falciparum 3D7 strain, and their mechanism of action was evaluated through a molecular docking study. Six curcumin analogs, i.e. 2,6-bis(2-hydroxybenzylidene)cyclohexanone; 2,6-bis(2-hydroxybenzylidene)cyclopentanone; 1.5-bis(2-hydroxyphenyl)penta-1,4-diene-3-one; 2,6-bis(3-hydroxybenzylidene)cyclo-hexanone; 2,6-bis(3-hydroxybenzylidene)cyclopentanone; and 1,5-bis(3-hydroxy-phenyl)penta-1,4-diene-3-one have been successfully synthesized. In addition, 2,6-bis(2-hydroxybenzylidene) cyclopentanone demonstrated the lowest IC50 value and binding affinity of 0.04 µM and -7.6 kcal/mol, respectively. Based on molecular docking studies, this compound also showed the most potent antimalarial activity targeted at PfATP6.
Phytotoxic and Cytotoxic Polyketides Produced by Fungal Endophytes Isolated from Psidium guajava Tendy Oktriawan; Nanang Ariefta; Tri Joko Raharjo; Endang Astuti; Takuya Koseki; Yoshihito Shiono
HAYATI Journal of Biosciences Vol. 30 No. 3 (2023): May 2023
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.4308/hjb.30.3.473-479

Abstract

Endophytic fungi reside within their host plants with no obvious symptoms. They have been proven as abundant sources of new bioactive compounds with diverse structures. In our continuous search of the new compound from endophytic fungi, a new compound, 5,7-dihydroxy-3(R)-methylphthalide (1), was isolated from Xylaria brevipes PGR1, and three known compounds, (–)-altenuene (2), alternariol (3), and altertoxin I (4), were isolated from Alternaria alternata D-8. Both endophytic fungi were isolated from the branch of an Indonesian medicinal plant, Psidium guajava. Their structures were elucidated using extensive spectroscopy analyses, including 1D/2D NMR, HRESITOFMS, and data comparisons with the literature. Compounds 1–3 exhibited phytotoxicity at IC50 (µg/ml) values of 4.6, 23.07, and 77.28, respectively. Additionally, 1–4 showed significant cytotoxicity in the brine shrimp lethality test (BSLT), with mortality rates at 75%, 50%, 90%, and 80% at the concentration of 0.19 μg/ml, respectively.