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All Journal Reaktor Bioma : Berkala Ilmiah Biologi Jurnal Natur Indonesia Biopropal Industri JURNAL BIOLOGI INDONESIA Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology ANNALES BOGORIENSES Jurnal Pascapanen dan Bioteknologi Kelautan dan Perikanan Teknologi Indonesia Annales Bogorienses Berita Biologi
Ahmad Thontowi
Research Center for Biotechnology-LIPI
Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Control & Systems Engineering Education Energy Environmental Science Immunology & microbiology Industrial & Manufacturing Engineering Materials Science & Nanotechnology Medicine & Pharmacology

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Optimization of Xylose Production from Sugarcane Trash by Microwave-Maleic Acid Hydrolysis Hermiati, Euis; Oktaviani, Maulida; Ermawar, Riksfardini Annisa; Laksana, Raden Permana Budi; Kholida, Lutfi Nia; Thontowi, Ahmad; Mardiana, Siti; Watanabe, Takashi
Reaktor Volume 20 No.2 June 2020
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (528.661 KB) | DOI: 10.14710/reaktor.20.2.81-88

Abstract

Sugarcane trash contains significant amount of xylan that could be hydrolysed to xylose. The xylose could be further fermented to produce xylitol, a sugar alcohol that has low calories and does not cause carries of teeth. In this study we optimized the production of xylose from sugarcane trash by microwave-assisted maleic acid hydrolysis using response surface methodology (RSM). The factors optimized were acid concentration, time, and temperature. The xylose yield based on the weight of initial biomass was determined and it served as a response variable. Results show that acid concentration and interaction between time and temperature had significant effect on xylose yield. The quadratic regression model generated from the optimization was fit and can be used to predict the xylose yield after hydrolysis with various combinations of acid concentration, time, and temperature. The optimum condition for xylose production from sugarcane trash was using maleic acid of 1.52%, and heating at 176 °C for 6.8 min. At this condition the yield of xylose was 24.3% per initial biomass or 0.243 g/ g biomass.Keywords: maleic acid; microwave heating; response surface methodology; sugarcane trash, xylose
Produksi Xilitol Menggunakan Hidrolisat Tongkol Jagung (Zea mays) Oleh Meyerozyma caribbica InaCC Y67 Faradila Ayu, Near Putri; Nurhayati, N; Thontowi, Ahmad; Kusdiyantini, Endang; Kanti, Atit; Hermiati, Euis
Bioma : Berkala Ilmiah Biologi Vol. 23, No 1, Tahun 2021
Publisher : Departemen Biologi, Fakultas Sains dan Matematika, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/bioma.23.1.71-77

Abstract

Xylitol (C5H12O5) is a non-carcinogenic polyalcoholic sugar. Xylitol is beneficial for diabetics because it can be metabolized without insulin. Corn cobs contain 30% xylose which can be fermented into xylitol by microorganisms. Xylitol can be produced by fermentation of xylose and few microorganisms. Meyerozyma caribbica is a yeast that has been proven to produce xylitol and inhibitor’s resistant. The aim of this research is to test the xylitol productivity by Meyerozyma caribbica InaCC Y67 using corn cobs hydrolyzate and the effect of the volume of fermentation media on xylitol productivity by Meyerozyma caribbica InaCC Y67. The method was carried out by culturing Meyerozyma caribbica InaCC Y67 as a starter on YPD media.  Fermentation using 100 mL Erlenmeyer with the variation of fermentation volume is 10 ml and 75 ml, agitation 175 rpm and 30 oC. Parameters were measured based on the dry weight of cells, xylose and xylitol. Data were analyzed using fermentation kinetics. The results of analysis showed that the higher xylitol production was found in the fermentation volume 75 ml with an efficiency value of 7,171%. The highest xylitol production was at the 48th hour with production value of 2.050 g/L. Results from research shows that Meyerozyma caribbica InaCC Y67 can produce xylitol with corn cobs hydrolyzate. The right volume of fermentation in the fermentation process can also increase the productivity of xylitol.
Medium Chain and Long Chain Alkanes Hydroxylase Producing Whole Cell Biocatalyst From Marine Bacteria Thontowi, Ahmad; Yetti, Elvi; Yopi, Yopi
Annales Bogorienses Vol. 22 No. 1 (2018): Annales Bogorienses
Publisher : BRIN

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Abstract

Alkanes are major component of crude oil that could be hydrolyzed by the enzyme of alkane hydroxylase. The are three types of alkane hydroxylase based on the chain length of alkane such as short-chain length/SCL (C2-C4), medium-chain length/MCL (C5-C17), and long-chain length/LCL (C>18). The aims of this study were to characterize and identify alkanes-degrading bacteria from these bacteria. The 30 strains from marine were grown on MCL (Pentane-C5H12, Decane-C10H22, and Pentadecane-C15H32) and LCL (n-Paraffin-C12H19C17 and branch of Pristane-C19H40). The study showed twenty-nine isolates have the ability to degrade alkanes compounds, whereas 14 isolates have grown ability on MCL and LCL medium, 11 isolates have the ability to grow on MCL and n-LCL, 3 isolates have the ability only to grow on MCL medium and 1 isolate has the ability only grow on n-LCL medium. The growth test result indicated that 29 isolates have medium-chain alkane monooxygenase and long-chain alkane hydroxylase. Based on 16S rDNA gene analysis, we obtained twenty nine of oil- degrading bacteria, namely a-proteobacteria (57 %), g-proteobacteria (30 %), Flavobacteria (7 %), Bacilli (3%) and Propionibacteriales (3 %). g-Proteobacteria and a-proteobacteria which seems to play an important role in the alkane biodegradation.
Optimization of Substrate and Starter Cell Concentrations for Dibenzothiopene Biodegradation by Indigeneous Marine Bacteria Mauricauda olearia LBF-1-0009, Alcanivorax xenomutants LBF-1-0018, and Stakelama pacifica LBF-1-0031 Yetti, Elvi; Thontowi, Ahmad; Yopi, Yopi
Annales Bogorienses Vol. 21 No. 2 (2017): Annales Bogorienses
Publisher : BRIN

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Abstract

Dibenzothiophene (DBT) and its derivatives have been widely used as model organic sulfur compounds in petroleum, included their biodegradation process. The abilities of microorganisms to degrade pollutants are significantly influenced by various factors such as microbial species, nutrients and environmental parameters. In this research, we carried out further study to determine optimal condition for DBT biodegradation regarding with substrate and strains cell concentration by several indigenous marine bacteria from Indonesia. These three isolates were belong to Mauricauda olearia, Alcanivorax xenomutants, and Stakelama pacifica, with homology result 99% each. Optimal dibenzothiophene as substrate reached by all isolates is 100 ppm, while cell concentration or microbial numbers that gave highest growth for all isolates is 20 based on conversion of OD600 nm measurement.
Alkane Degradation and Detection of Mono-xygenase Gene from Alcanivorax sp. from Jakarta Bay Thontowi, Ahmad; Yopi, Yopi
Annales Bogorienses Vol. 15 No. 2 (2011): Annales Bogorienses
Publisher : BRIN

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Abstract

Alkanes is a major component of crude oil that can be hydrolized by enzyme alkane monooxygenase from bacteria. Nine oil-degrading bacteria were analyzed their capability to degrade alkanes (pristane and paraffin). The result of growth test on paraffin and pristane were showed that 9 isolates could be divided into two groups. First group (BL09, BL31 and BL45) could degrade both paraffin and pristane, and second group (BL01, BL06, BL44, BL057, BL058 and BL071) preferred to degrade paraffin than pristane. Three isolates (BL09, BL31 and BL45) have activity to decrease paraffin and pristane until less 50% remain. Based on homology analysis of 16SrRNA gene sequences showed that isolates No. BL09, BL31 and BL45 were identified as Alcanivorax sp. and the partial sequences of the alkB gene from those three isolates are showing 66-68% of identity compare with some mono-oxygenase gen from database of genbank.
Polyaromatic Hydrocarbon Degradation and Dioxygenase Gene Detection from Alteromonas alvinellae Bt05 Thontowi, Ahmad; Rahmani, Nanik; Yopi, Yopi
Annales Bogorienses Vol. 17 No. 1 (2013): Annales Bogorienses
Publisher : BRIN

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Abstract

Bto5 is marine bacterium
A CONTROL OF OXYGEN SUPPLY IN BIOCONVERSION OF SUGARCANE TRASH INTO XYLITOL BY Meyerozyma guilliermondii InaCCY65 Thontowi, Ahmad; Kanti, Atit; Listiyowati, Sri; Meryandini, Anja
Berita Biologi Vol 23 No 3 (2024): Berita Biologi
Publisher : BRIN Publishing (Penerbit BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/berita_biologi.2024.7720

Abstract

Xylitol is a sugar alcohol used as a sugar substitute for several prevention of health cases such as dental diseases, diabetes, and other health problems. Bioconversion of xylose into xylitol needs an optimum oxygen supply for xylitol synthesis. This research aims to determine the effect of dissolved oxygen on hydrolysate fermentation from sugar cane leaf as a source of xylose to xylitol by Meyerozyma guilliermondii InaCCY65. Dissolved oxygen was varied in aeration and fermentation agitation using a 3L scale bioreactor. Analysis of cell growth for several kinetic parameters during fermentation, xylose reductase, and xylitol dehydrogenase activity. Bioconversion of sugarcane trash hydrolysate into xylitol by M. guilliermondii InaCCY65 is influenced by the oxygen transfer coefficient (kLa) and aeration conditions. The increase in kLa number showed increased cell growth, xylose consumption, xylitol production, and decreased InaCCY65 cells. The optimum conditions of kLa were obtained at 45/h with 39 g/L xylitol production under the aeration effect. Optimum aeration in the bioconversion of sugarcane trash (SCT) hydrolysate become xylitol by M. guilliermondii InaCCY65 is 1.0%; under these conditions, xylitol yield and xylitol productivity are 0.78 g/g and 1.20 g/Lh. The effect of oxygen in the bioconversion of xylose to xylitol also has an impact on xylose reductase (XR) and xylose dehydrogenase (XDH) activities of M. guiellermondii InaCCY65. The results showed that the dissolved oxygen concentration must be carefully controlled during xylitol bioconversion to obtain efficient xylitol.
Co-Authors - Yopi A.A. Ketut Agung Cahyawan W ADE ANDRIANI Anja Meryandini Atit Kanti BAMBANG SUNARKO Elvi Yetti, Elvi Endang Kusdiyantini Euis HERMIATI Faradila Ayu, Near Putri Hadi, Sofjan Hadi, Sofjan Hapzi Ali Kholida, Lutfi Nia Kusmiati Kusmiati Laksana, Raden Permana Budi Maemonah, Maemonah N Nurhayati NANIK RAHMANI Ni Nyoman Tri Puspaningsih Ni'mahtuzahroh, Ni'mahtuzahroh NUNIK SULISTINAH Nuzul Farini, Nuzul Oktaviani, Maulida Purkan Purkan, Purkan Purwoko, Agus Putra, Filemon Jalu Nusantara Riksfardini Annisa ERMAWAR Safitriani, Safitriani Safitriani, Safitriani Siti Mardiana Sri Listiyowati Sukma Nuswantara Suryani Suryani Susiana Purwantisari Takashi Watanabe Tanjung, Puspasari Noerwan Tanjung, Puspasari Noerwan Wijaya, Hans YOPI YOPI