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SELECTION AND IMMOBILIZATION OF ISOLATED ACETIC ACID BACTERIA ON THE EFFICIENCY OF PRODUCING ACID IN INDONESIA Kuswanto, Kapti Rahayu; Djokorijanto, Sri Luwihana; Lino, Hisakazu -
Joglo Vol 26, No 1 (2013): Joglo
Publisher : Joglo

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Abstract

Screening of AAB(Acetic acid bacteria) isolates from cane sugar juice in Indonesia for acid and alcohol tolerance was performed. Among the isolates tested, strain INT-7 was observed to grow to as high as 9% acetic acid and 15% alcohol. Based on the screening study, INT-7 is belong to Acetobacter pasteurianus were chosen for vinegar fermentation. The pure culture of strain INT-7 on unpasteurized coconut sap was found to have high acidity (5.42%) compared to pasteurized sap (3.42%). Strain INT-7 exhibited higher acid production of 62.7g/L in 5% ethanol under static condition compared to reference strains JCM 7640 Acetobacter aceti and JCM 7641 A. pasteurianus with 52.3g/L and 30.8g/L acid, respectively. On other study, results revealed the efficiency (2X) of using fermentor for acid formation compared to samples fermented with shaking. In addition, the crude metabolites of INT-7 suggest inhibitory effect against the growth of E.coli and Salmonella sp. but not against S. aureus, while strain of INT-17 metabolites inhibited the growth of all pathogenic bacteria tested. The immobilization of A.pasteurianus strain INT-7 for improving the ethanol resistance was done in the alginate gel. The result showed that optimum condition of A. pasteurianus INT-7 cell entrapped (107CFU/mL) on 3% alginate and the ratio of cell number and alginate solution was 1:3 v/v. The optimum condition of acetic acid fermentation by immobilized cells were initial pH 6.0, ethanol concentration 7.5% (v/v), temperature at 30o C for 7 days produced acetic acid (35.81 g/L) is higher than free cells (16.29 g/L). The efficiency of fermentation by immobilized cells and free cells were 36.73% and 16.71%, respectively.   Keywords: Acetic acid bacteria, selection, immobilization, producing higher acid.
Fermentasi Asam Asetat dengan Sel Amobil Acetobacter pasteurianus INT-7 dengan Variasi Ph Awal dan Kadar Etanol Luwihana, Sri; Kuswanto, Kapti Rahayu; Rahayu, Endang Sutriswati; Sudarmadji, Slamet
Agritech Vol 30, No 2 (2010)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1073.07 KB) | DOI: 10.22146/agritech.9683

Abstract

The objective of this study was the optimation condition of acetic acid fermentation by Acetobacter pasteurianus INT-7 immobilized cells. In this study cells immobilized with initiate cell numbers 107 CFU/mL and in 3 % alginate solution, ratio of cells number and  alginate was 1:3 (v/v) and  immobilized cells were conditioned  in PGY growth medium supplemented with 2 % ethanol on shaker incubator 150 rpm 30 oC for 1 day and then washed twice with sterile aquad- est. Fermentation was done in YEPM (Yeast extract pepton malt) on  variation of initial pH (5,5; 6,0 and 6,5) and ethanol concentration (5,0; 7,5 and 10 % w/v)  on shaker incubator 150 rpm, 30 oC for 10 days long. The acetic acid production and the cell numbers were monitoring for 1, 3, 5, 7, 8, 9 and 10 days fermentation. The result showed that the optimum condition for acetic acid production by immobilized cells of A. pasteurianus  INT-7 were initial pH 6,0; ethanol concentration 7,5 % w/v for 7 days fermentation. The immobilization cells could be increase  the resistency of ethanol and  prolong to achieve of the  optimal fermentation time. The acetic acid production of the fermentation by immobilized cell was 35,81 g/L and 16,29 g/L by free cell, the theoritical efficiency of immobilized  cell and free cell were (36,73 %) and (16,17 %) respectively.ABSTRAKTujuan penelitian ini adalah mendapatkan kondisi optimum fermentasi dengan sel amobil dan hasilnya dibandingkan dengan sel bebas. Penelitian ini diawali dengan pembuatan sel amobil dengan jumlah sel awal 107  CFU/mL, larutan alginat 3 %, ratio jumlah sel dan alginat 1:3 (v/v) dan pengkondisian sel amobil pada media pertumbuhan PGY-2 % etanol (pepton glucose yeast extract) pada inkubator goyang 150 rpm, 30 oC selama 1 hari. Sel amobil yang sudah dikondisikan dicuci 2 kali dengan akuades steril dan siap digunakan untuk  fermentasi menggunakan media YEPM (yeast extract pepton malt) dengan variasi pH awal (5,5;6,0 dan 6,5), kadar etanol (5,0; 7,5 dan 10 % b/v) dan waktu fermentasi pada inkubator goyang 150 rpm, 30 oC selama 10 hari. Pengukuran produksi asam asetat dan jumlah sel dilakukan pada hari 1, 3, 5, 7, 8, 9 dan 10 hari. Hasil  penelitian  menunjukkan bahwa  kondisi  optimum fermentasi dengan  sel amobil adalah pH awal media 6,0; kadar etanol 7,5 % suhu 30 oC selama 7 hari. Penggunaan sel amobil dalam fermentasi asam asetat dapat meningkatkan resistensi  etanol  dan  waktu  optimum fermentasi dicapai lebih lama. Fermentasi dengan sel amobil Acetobacter pasteurianus INT-7 pada kondisi optimum menghasilkan asam asetat sebesar 35,81 g/L dan 16,29 g/L pada fermentasi dengan sel bebas. Efisiensi fermentasi dengan sel amobil (36,73 %) lebih besar daripada sel bebas (16,17 %).
Phenolic content and antibacterial properties of various extracts of gambir (Uncaria gambir Roxb) Pambayun, Rindit; Gardjito, Murdijati; Sudarmadji, Slamet; Kuswanto, Kapti Rahayu
INDONESIAN JOURNAL OF PHARMACY Vol 18 No 3, 2007
Publisher : Faculty of Pharmacy Universitas Gadjah Mada, Yogyakarta, Skip Utara, 55281, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (185.053 KB) | DOI: 10.14499/indonesianjpharm0iss0pp141-146

Abstract

Extraction of gambir product with various solvents gave vary in amount of yields, phenolic contents, and its antibacterial properties. Extraction was performed by maseration and Soxhlet methods with some solvents; chloroform, ethyl acetate, ethanol, water, and their combination. The results showed that the highest yield of extract obtained from the solvent combination of ethanol and water (1:1 v/v) both at the maseration and Soxhlet metods, i.e. 84.77 and 87.69 %, respectivelly. Soxhlet method gave the yield of extract higher than that of maseration method. The highest phenolic content was found at the extracts using ethyl acetate both in maseration and soxlet methods, i.e. 88,30 and 90,85 %, respectivelly. Antobacterial properties on the Gram-positive bacteria such as Streptococcus mutans, Staphylococcus aureus, and Bacillus subtilis, indicated that the extracts extracted by using ethyl acetate gave highest inhibitory properties. On the other hand, the extracts did not inhibit Gram-negative bacteria. Extraction was continued by using solvent combination of ethanol and water at the various proportion and at the three levels of temperature, 4, 30, and 60 °C. The results showed that solvent combination of ethanol and water (1:2), gave the highest yield of extracts but lower in phenolic contents and aantibacterial properties.Key words: antibacterial, phenolic content, extract of Uncaria gambir Roxb
Isolation and Purification of Oxalate Oxidase From Barley Seedling Kuswanto, Kapti Rahayu
Agritech Vol 11, No 3 (1991)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1930.169 KB) | DOI: 10.22146/agritech.19223

Abstract

A procedure of isolation of oxalate oxidase from barley seedling and a new method for purification is described. A purification step was accomplished by the second partition using polyethylene glycol (PEG-6000) and Devi-Iran-500 (4.5%1 4), and affinity chromatography using oxalate immobilized on activated CNBR-Sepharose 6MB as a ligand. After partition some protein were separated, and the specific activity were increased by 5-30 fold. The affinity chromatography using Oxalate-Sepharose effectively separated the oxalate oxidase. The specific activity of pure enzyme was 154.3 U/mg protein and the purity was 41 fold.
Pengaruh Konsentrasi Xilosa dan Kosubstrat Terhadap Produksi Xilitol oleh Candida shehatae Way 08 Yulianto, Wisnu Adi; Kuswanto, Kapti Rahayu; Tranggono, Tranggono; Indrati, Retno
Agritech Vol 25, No 3 (2005)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1305.504 KB) | DOI: 10.22146/agritech.13352

Abstract

The objectives of the research were to determine the optimum cultivation condition of initial xylose concentration, type of cosubstrate and ratio of cosubstrate to substrate (xylose) for xylitol production by Candida shehatae WAY 08. The initial xylose concentrations were varied within the range of 2-14 %. The cosubstrates were arabinose, galactose, glucose, and mannose. Ratios of cosubstrate to xylose were the range of 1:6 - 3:6 %. The fermentation was performed at 30`C in a 500 ml Erlenmeyer flask placed in a shaker incubator at 200 rpm for 72 h. Biomass concentration was determined by drying method. Xylose, cosubstrate and xylitol concentrations were determined using HPLC. The result indicated that with the medium containing 6 % xylose produced the highest product yield ( 0,75 g/g) and xylitol volumetric productivity was 0,73 g/Lh. The addition of cosubstrate of arabinose increased xylitol production, while the addition of glucose, galactose, and mannose decreased its productions.
Aspergillus Proteolitik Indigenous dari Koji dan Kemampuannya Mendegradasi Aflatoksin B1 Sardjono, Sardjono; Rahayu, Endang Sri; Raharjo, Sri; Kuswanto, Kapti Rahayu
Agritech Vol 24, No 3 (2004)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1733.858 KB) | DOI: 10.22146/agritech.13461

Abstract

Legume and cereals are always exposed to the danger of fungal contamination. Among such fungi, some species of the genus Aspergillus are potential of aflatoxins producer. Aflatoxin BI (AFB1) which is the most carcinogenic mycotoxins , known very stable under cooking condition and other processing factors. The removal of AFB1 by degradation or detoxification is critical to reduce risk to human health. Microbiological degradation is a promising method for AFB1 degradation compared to others. The aim of this research was to isolate the proteolytic Aspergillus strain from "koji" and to determine its ability to degrade AFB). Out of 18 strains of Aspergillus, 16 strains were found proteolytic and only 5 strains had no afiatoxigenic properties, but all of them were able to degrade AFB1. There were no spesific pattern of the rate of AFBI degradation. Strain of KKB4 was identified as Aspergillus oryzae, that possess the highest ability to degrade AFB1. Two kind of substances were formed after degradation which were more polar than AFB1. The rate of AFB) uptake by Aspergillus oryzae KKB4 was similar with that of mycelia! growth. Aflatoxin BI inhibits mycelium growth, vesicle and conidial head formation.
Some Characteristics of Oil Palm and Sago Starch Acetates Haryadi, Haryadi; Kuswanto, Kapti Rahayu
Agritech Vol 17, No 2 (1997)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (988.736 KB) | DOI: 10.22146/agritech.19328

Abstract

Pati kelapa sawit dan pati sagu diasetilasi dengan anhidrid asetat pada suhu 25°C dalam larutan alkali. Tingkat pemberian anhidrit asetat adalah 2,5 - 15,0 %, berdasar berat kering pati. Pati asetat yang diperoleh dicirikan mengenai tingkat substitusi (DS), perilaku pembentukan pasta, kemampuan penggelembungan, dan kedapat cernaannya menggunakan amilase pankreas babi. Hasilnya menunjukkan bahwa makin banyak tingkat pemberian anhidrid asetat menghasilkan pati dengan DS makin besar. Prosedur modifikasi yang dilakukan menghasilkan turunan pati dengan DS 0,007 - 0,095 untuk pati kelapa sawit, dan DS 0,041 - 0,056 untuk pati sagu. Asetilasi berakibat menurunkan suhu pembentukan pasta, meningkatkan kemampuan penggelembungan, dan menurunkan kedapatcernaannya secara in vitro. Pati kelapa sawit dan turunannya memiliki suhu pembentukan pasta yang lebih rendah dari pada pati sagu dan turunannya. Sifat-sifat pati kelapa sawit mirip dengan sifat-sifat pati sagu dalam beberapa hal.
Peranan HACCP dalam Industri Pangan Kuswanto, Kapti Rahayu
Agritech Vol 15, No 4 (1995)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1604.741 KB) | DOI: 10.22146/agritech.19296

Abstract

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Some Characteristics of Cross-Linked Hidroxypropyl Sago Starch Haryadi, Haryadi; Kuswanto, Kapti Rahayu
Agritech Vol 16, No 4 (1996)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1564.12 KB) | DOI: 10.22146/agritech.19316

Abstract

Sago starch was laboratory hydroxypropylated using 1% propylene oxide in alkaline condition, then cross-linked using 9.000 - 0.025 % phosphorus oxychloride. The dual modified starches with level of cross-linking ranging from 0.0000 to 0.0186 were characterized for amylographic properties, swelling power, paste turbidity, and in vitro digestibility using porcine pancreatic a-amylase. The cross-linking procedure applied to dual modification nearly unchanged the pasting temperature, i. e. at 62.5°C. Cross-linked, hydroxypropyl starches with DS more than 0.0150 had similar amylographic properties which showed high heat and shear stability of the paste. Cross-linking resulted in decrease in the swelling power and the in vitro digestibility of the starch. Hydroxypropylationprior to subsequent modification facilitate the cross-linking with a consequence of lower pasting temperature, higher maximum viscosity, higher swelling power, and lower digestibility.
The Role of Extracellular Enzymes Produced by Aspergillus oryzae KKB4 in Biodegradation of Aflatoxin B1 Sardjono, Sardjono; Raharjo, Sri; Rahayu, Endang S; Kuswanto, Kapti Rahayu
Indonesian Food and Nutrition Progress Vol 11, No 2 (2004)
Publisher : Indonesian Association of Food Technologists

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jifnp.40

Abstract

Previous research showed that Aspergillus oryzae KKB4 able to degrade aflatoxin B1 (AFB1) during its growth. According to detoxification test, it was known that extracellular enzymes produced by this mold was able to detoxify AFB1. In this study, the role of these enzymes in biodegradation of AFB1 were further studied. Biodegradation products of AFBI were analyzed using HPLC and the destruction of functional groups were analyzed using IR spectrophotometer. Molecular weight and enzymes activity were also determined. The result showed that extra cellular enzymes of Aspergillus oryzae KKB4 consist of five fractions with molecular weight of 14.2, 20, 23, 29 and 36 kDalton. All enzyme fractions were able to degrade AFB1 with the highest specific activity 3.79 ìg AFBl/mg enzyme protein/20 hrs. The HPLC analysis indicated that biodegradation product of AFB1 was different from untreated AFB1. The infrared spectrum suggest that enzymes degraded lactone ring, cyclo-pentanone reduction and openined difuran ring.