Annales Bogorienses

Number 1, 2010

1-9
Application of Microwave Heating in Biomass Hydrolysis and Pretreatment for Ethanol Production

Authors: Euis Hermiati, Djumali Mangunwidjaja, Ttiti C Sunarti, Ono Suparno, Bambang Prasetya

Abstract

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Number of views: 337

Recently, due to depletion of fossil derived energy stock in the world, there are growing interests in utilizing biomass sources of bioethanol. There are basically two types of biomass that are usually used or converted to ethanol, starchy and lignocellulosic biomass. The conversion of starchy and lignocellulosic materials are widely explored, however, there are still some drawbacks, such as high enzyme cost and intensive energy needed. Therefore, lower cost as well as energy and time efficient process technology in biomass conversion to ethanol is important in enhancing the use of biomass to substitute fossil fuel. Microwave heating offers some advantages to overcome these drawbacks, especially due to its quick heat transfer and its heating selectivity. In conventional heating the heat was transferred through conduction or convection process which took longer time. Thus, by using microwave, degradation of starchy and lignocellulosic biomass could be completed in shorter time than by using conventional heating method. The roles of microwave heating in the degradation of biomass, especially starchy and lignocellulosic biomass and its relation to the hydrolysis and pretreatment of that particular biomass for ethanol production are reviewed and discussed.

1-8
Conservation of Major L1 and Variability of Minor L2 Capsid Late Protein Genes in Human Papillomavirus of Indonesia Variants

Authors: Sukma Nuswantara, Titik K Prana, Dwi Wulandari, Henni Widyowati, Vera Anzela, Dea Levy, Petrus Cahyadi, Lukas D Tjandra

Abstract

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Number of views: 318

Human Papilloma Virus (HPV) has an out standing feature for its vast intraspecies variability. Of all known 100 types or more, 15 t ypes of them are classified as high risk because of their occurrence in more than 95% of cervical cancer cases. Among all genes in their genome, E6 and E7 genes are considered oncogenes and have close relevance with their pathogenicity, whilst L1 and L2 ge nes produce capsid proteins that directly interact with their host receptors. Considering the importance of L1 and L2 in host-receptor relationship, we tried to investigate their molecular variability thereby uncover their specificity as Indonesian variant s. Here we reported about the conservation of L1 minor capsid protein and variability of L2 capsid protein among high-risk types Human Papilloma Virus (HPV). The results indicated that L1 DNA was relatively more conserved than its L2 counterpart Also it was indicated that the middle part of either L1 or L2 CDS‟ showed more DNA variability than those at their upstream sequences. It is concluded that L2 middle sequences are important factors for intraspecific variations found in HPV of Indonesian variants.

11-17
Control of Biodegradability of Polyurethane Foam Based on Palm Oil by Ratio of Soft Segment on the Polymer Backbone

Authors: Agus Haryono, Evi Triwulandari, Dewi Sondari, Ahmad Randy, Asep Muhamad Ridwanuloh

Abstract

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Number of views: 373

Polyurethane is polymer synthetic which is formed by reaction between polyols and polyisocyanates.polyols are compounds which contain two or more hydroxyl groups. Polyurethane can be applied in various forms, such as foam, elastomeric, coating and adhesive. In this work, we developed pol yurethane foams by using polyols based on palm oil. Palm oil based polyols as soft segments in the polyurethane backbone accelerate biodegradable process of the polyurethane. Biodegradability is the ability of material to be utilized as a carbon source by microorganisms and converted safely into carbon dioxide, biomass and water. Commercially available polyurethane foams are usually produced from petrochemical based polyols that they are not biodegradable. The biodegradability study was conducted by using Aspergillus niger (fungi) and Pseudomonas aeruginosa(bacteria), with variation of method and media for biodegradation. Rigid polyurethane foam was synthesized by using one shoot process method, which is reaction between palm based polyol mixture and methylene diphenly diisocyanate (MDI) at room temperature. The effect of variation of ratio of polyisocyanates (NCO) as hard segment and polyols (OH) as soft segment to the properties of polyurethane foams were studied in detail. Study of the effect NCO/OH ratio was conducted with variation ratio of 0.8, 1.0 and 1.2. Increasing hard segment (NCO) ratio to the soft segment (OH) affected in the decreasing of hydrophilicity of foam. Thus,the penetration of water into bulk of polymer decreased. The biodegradability of foam was also affected by the soft segment ratio on the polymer backbone.

19-24
Screening for Natural Producers Capable of Producing 1,3-Propanediol from Glycerol

Authors: Dian Andriani, Wien Kusharyoto, Bambang Prasetya, Thomas Wilke, Klaus Dieter Vorlop

Abstract

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Number of views: 297

Glycerol is a renewable resource found as the main by-product in the transesterification of triglycerides and fat saponification. Due to the increased production of plant oils, especially palm oil in developing countries, and their larger use by the oleochemical industry, glycerol surpluses are on the world market and this may result in a desrease in glycerol price. As a consequence, biotechnological processes have been developed to convert this substrate into value-added products, such as 1,3-propanediol (1,3-PD). The microbial production of 1,3-PD could be competitive to chemical routes assuming that it is based on cheap raw material and an optimized process. In the screening for 1,3 PD–producing bacteria, raw glycerol as by-product from rapeseed oil processing unit was used as a carbon source compared with commercial glycerol. By using increasing concentration of both glycerols from 50 to 150 g/l, two potential bacteria were obtained from soil samples.BMP 1 was obtained from an enrichment culture using 50 g/l commercial glycerol, while BMR-1 was obtained from an enrichment culture using 100 g/l raw glycerol. The highest conversion yield obtained using the isolateBMP-1 was around 0.62 g 1,3-PD formed per mol glycerol consumed, and 0.73 mol 1,3-PD formed per molgycerol using the isolate BMR-1. No bacteria were obtained from cultures using 150 g/l commercial and rawgycerol, respectively, which indicated that higher concentration of glycerol has inhibition effect.

25-30
The Influence of Harvesting Period on Lipid Associated Antioxidant Activity of Semicontinuously Grown Chlorella vulgaris

Authors: Tjandara Chrismadha, Diani Sartika, Iriani Setyaningsih, Uju Uju

Abstract

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Number of views: 358

A green alga, Chlorella vulgaris was grown semi-continuosly at various harvesting periods, and the lipid content and its associated antioxidant activity was examined. The harvesting periods were 9, 18, and 27 days, while the algal culture was placed in 10 L glass bottles provided with aeration for gas exchange and mixing. Light was obtained from 440 watt cool fluorescent lamps placed at one side of the culture. Room temperature was 26-32C. Algal lipid extraction was done based on liquid phase separation of methanol :chloroform:water and the antioxidant activity was examined by means of oxidation inhibitory in ethanol emulsified limnoleic acid. In addition, a TLC analysis was performed to identify the antioxidant compouns soluble in the lipid. The results showed that harvesting per iod had a significant influence on the algal lipid content, which were 11.94, 12.96, and 16.51% of the dry weight in the culture with harvesting periods of 9, 18, and 27 days, respectively. No remarkable effect of the harvesting period on the antioxidant activity, which were observed to inhibit oxidation of linoleic acid up to 67-71%. There were five compounds found can be associated with the algal antioxidant activity, which were pheophorbide -a, chlorophyll-b, chlorophyll-a, phaeophytin-a, -carotene, and an unidentified one.

31-37
Screening and Optimization of Cellulase Production of Bacillus subtilis TD6 Isolated from Takifugu rubripes Fish

Authors: Dian Andriani, Don Hee Park

Abstract

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Number of views: 348

Cellulase enzymes have attracted considerable attention in recent years due to their great biotechnological and industrial potential. Cellulase enzymes provide a key opportunity for achieving tremendous benefits of biomass utilization through the bioconversion of the most abundant cellulosic material into the simplest carbohydrate monomer, glucose. Nowadays, the sources of cellulase-producing bacteria have been broadened into thepresence of symbiotic bacteria in herbivorous animal and also from marine. Takifugu rubripes or known as puffer fish is a unique poisonous vertebrate but nevertheless is considered a delicacy in Korea. The diet of the puffer fish includes mostly algae. This dietary habit considers Puffer fish as host of cellulase-producing bacteria, especialy on its gut. In the present study an attempt has been made to search for the cellulolytic bacteria in the gut of Takifugu rubripes. Fifty five microorganisms have been isolated using 1% (w/v) Carboxymethyl cellulose (CMC) as substante Congo red dye test and DNS method were then used for screening the extracellular celuase activity of the strains. Among them, TD6 strain has shown the highest performance in term of cellulose activity. In order to evaluate the optimum culture condition of the isolate TD6 for cellulase production, the strain was grown at various temperatures, pH, carbon sources, and nitrogen sources. Under optimum condition, the maximum specific activity of 2.13 U/mg protein was achieved after growth the strain with 1.5% CMC at 45ºC PH 6 for 3 days, respectively Based on 16S rRNA gene analysis it is proposed that the strain was identified as Bacillus subtilis.

39-46
Rapid Assessment of Diverse Trichodermal Isolates of Indonesian Origin for Cellulase Production

Authors: Fahrurrozi Fahrurrozi, Shanti Ratnakomala, Trisanti Anindyawati, Puspita Lisdayanti, Endang Sukara

Abstract

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Trichoderma is a well -known candidate to be promoted as cellulase producer for the hidrolysis of lignocelluloses that contain in woody biomass. The number of trichodermal isolates in our laboratory collected from diverse ecosystem types in Indonesia increases significantly during the last 5 years. It is our aim to assess the cultures for its ability in producing cellulase. Sixty-six trichodermal isolates used in this experiment are obtained from Biotechnology Culture Collection (BTCC), Research Center for Biotechnology, Indonesian Institute of Sciences(LIPI) The 31 isolates were isolated from District of Liwa (South Sumatra, Indonesia) and the 35 isolates from District of Maros (South Sulawesi, Indonesia). The isolates were screened qualitatively, 7 isolates from Liwa and 12 isolates from Maros showed cellulolytic activity. From the results of quantitative test, two strains (ID08-T004 and ID08-T63) showed the higher cellulolytic activity among the selected strains, 133.5 and 133.5 U/ml, respectively. These extracellular enzymes were characterized their temperature and pH optimum. The temperature optimum for both enzymes was the same, 50C, with activity 213.6 U/ml for enzyme extracted from ID08-T004 and 197.3 U/ml for enzyme from ID08-T0063. The pH optimum was pH 5 of ID08-T004 with activity137.7 U/ml and pH 6 for ID08-T063 with activity 75.0 U/ml. The enzymes from ID08-T004 and ID08-T063 were stable in their temperature and pH optimal condition even after 90 minutes incubation with activity 179.0 U/ml and 86.7 U/ml, respectively. The enzyme stability was approximately 150 minutes for both enzymes in the temperature and pH optimum.