Makara Journal of Science
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Xylooligosaccharide Production from Tobacco Stalk Xylan using Xylanase Streptomyces sp. BO 3.2
No full textTobacco stalk (TS), which is one type of lignocellulosic material, has a xylan content of up to 21.9%. Lignocellulose can be used to produce xylooligosaccharides (XOs). XOs are dietary fibers that have prebiotic activity. This study aimed to produce XOs from tobacco stalk xylan using xylanase from Streptomyces sp. BO 3.2. After the TS was delignified, the xylan was extracted using the alkali method. The delignification process, which used 1% natrium hypoclorite (NaOCl), decreased the lignins from 32.93% to 18.15%. Xylan extraction was conducted using 10% natrium hydoroxide (NaOH); this extraction produced xylan of 15.53% (w/w). The xylanase produced by Streptomyces sp. BO 3.2 on a 0.5% TS medium had 5.92 U/mL of activity, with the optimum condition occurring at pH 5.5 and a temperature of 60 °C. The xylanase was stable, at temperature 4 °C and 30 °C for 120 hours. The xylanase Streptomyces sp. BO 3.2 was capable of hydrolyzing 2% TS xylan and 2% beechwood xylan during the first, third, sixth, and twelfth hours of incubation time; it also produced XOs with degrees of polymerization (DP) of 2.18 and 2.15, respectively. A Thin layer chomatography (TLC) analysis indicated that the hydrolysis products were XOs with the absence of xylose, glucose, and arabinose
Enzymatic Hydrolysis of Mannan from Konjac (Amorphophallus sp.) Using Mannanase from Streptomyces lipmanii to Produce Manno-oligosaccharides
No full textMannan is an abundant polysaccharide that can be found in konjac (Amorphophallus sp.). Mannan can be enzymatically hydrolyzed using mannanase to produce manno-oligosaccharides which can be used as a prebiotic. The aims of this research are to determine the production time of mannanase from Streptomyces lipmanii, perform enzyme characterization, optimize the hydrolysis time, and characterize the hydrolysis product. A qualitative assay using the indicator Congo red showed that S. lipmanii generated a clear zone, indicating that S. lipmanii produced mannanase in konjac medium and possessed mannanolytic activity. Enzyme activity was determined through reducing sugar measurement using the dinitrosalycylic acid method, and optimum enzyme production was achieved at the second day of culture. Characterization of the enzyme showed that hydrolysis was optimum at pH 7 and at a temperature of 50 oC. The reducing sugar content was increased by an increasing the hydrolysis time, and reached an optimum time at 2 h. The degree of polymerization value of three was achieved after 2 h hydrolysis of mannan from konjac, indicating the formation of oligosaccharides. Analysis by thin layer chromatography using butanol, acetic acid, and water in a ratio of 2:1:1 as eluent showed the presence of compounds with a retention time between those of mannose and mannotetrose. Confirmation was also performed by HPLC, based on the retention time
Co-digestion of Sorghum Stalk and Sludge for Biogas Production
No full textThe recycling of residual agricultural biomass using anaerobic digestion allows for the recovery of biomass carbon and nutrients as sources of energy and fertilizer. The obstacles that are encountered in this process include the lignocellulosic structure of biomass tissue and its high carbon-to-nitrogen (C:N) ratio. This study evaluates the co-digestion system of pretreated sorghum stalks and wastewater sludge. The stalks were pretreated by partial bio-oxidation to improve their bacterial accessibility. The digesters were fed a mixture of stalk and sludge at ratios of 100:0, 80:20, 60:40, and 40:60 (total solids [TS] basis). The digesters were run in batches at 35-36 °C, with an initial TS of 15%. The digesters’ performance was evaluated in terms of biogas production rate and yield. The digesters that were run with feed ratios of 80:20 and 60:40 showed shorter lag phase, higher biogas generation rates, and higher biogas yields compared to those run with feed ratios of 100:0 and 40:60. The highest specific biogas production (of 122 L/kg TS) was achieved by the digesters run at ratios of 80:20 and 60:40. The digesters run only with stalks (ratio 100:0) resulted in specific gas production of 67 L/kg TS, whereas those fed on a feed ratio of 40:60 generated only 13 L/kg TS. We conclude that the co-digestion of sorghum stalks and wastewater sludge at a proper ratio improves biogas production
Effect of Mg2+ and Fe2+ Concentrations in Culture Medium on CGF Formation from Microalgae Chlorella Pyrenoidosa Ink and Analysis of Amino Acids by Liquid Chromatography-Mass Spectrometry
No full textChlorella pyrenoidosa (C. pyrenoidosa) contains Chlorella Growth Factor (CGF), which consists of proteins and polysaccharides. CGF is located inside the nucleus of cells and is beneficial to humans as a food supplement, an immunity booster, and an antioxidant. CGF formation of C. pyrenoidosa is influenced by medium composition. C. pyrenoidosa INK was cultured in a modified basal medium (MBM) with various concentrations of Mg2+ (0.5, 1.0, and 1.5 g/L) and Fe2+ (3.5×10-4 and 5.0×10-4 g/L). The experiments were performed and analyzed under a completely randomized design using a 2-L bottle with three replications. The results showed that MBM with 1.0 g/L of Mg2+ and 3.5×10-4 g/L of Fe2+ yielded the optimal growth curve for C. pyrenoidosa. Analysis of protein content was carried out using the Lowry method with a spectrophotometer at λ=750 nm, and the obtained results were 0.0974 mg/mL (extract) and 6.4097 mg/ml (supernatant). Furthermore, analysis of glucose content was carried out using the phenol sulfate method (λ = 490 nm), and the obtained results were 49.331 ppm (extract) and 1566.911 ppm (supernatant). Analysis of amino acids in CGF using liquid chromatography-mass spectrometry (LC-MS) indicated the presence of tyrosine, proline, glutamate, alanine, valine, tryptopan, phenylalanine, methionine, and leucine-isoleucine
Identification and Bioactivity Studies of Flavonoid Compounds from Macaranga hispida (Blume) Mull.Arg
No full textTwo flavonoid compounds, 5,7,3’,4’-tetrahydroxy-6-geranylflavonol (1) and kaempferol 7-O-β-glucose (2) have been isolated from the leaves of Macaranga hispida (Blume), Mull.Arg. Isolation and purification were conducted by chromatography methods and chemical structure characterization was carried out by spectroscopic methods. The 5,7,3’,4’-tetrahydrxyi-6-geranyl flavonol (1) and kaempferol 7-O-glucose (2) had moderate cytotoxic activity against murine leukemia P-388 cell lines with IC50 value of 0.22 and 101.5 μg/mL, respectively. The IC50 for antioxidant activities of (1) and (2) were 2.83 and 13.95 μg/mL, respectively. The LC50 of (1) and (2) from BSLT were 350 and >1000 μg/mL, respectively. 
Optimization of Trypsin-like Protease Production by Lactobacillus plantarum FNCC 0270 using Response Surface Methodology
No full textThe purpose of this study was to get optimum medium composition and agitation to trypsin-like protease production by Lactobacillus plantarum FNCC 0270. The medium composition and agitation for enzyme production was optimized using Central Composite Design and Response Surface Method with Design Expert software version 7.1.5 Fermentation was carried out in erlenmeyer flasks at initial pH 8, 37 °C, using an incubator shaker at 87.5 rpm. The best results showed an enzyme activity of 1.0 mU/mL, a protein level of 0.557 mg/mL, and desirability value of 0.740. Numerical optimization was performed to approach the ideal state of the fermentation or the desirability value of 1. The medium composition containing of 3.64% baker's yeast, 1.21% glucose, and 0.13% skim milk was used for the fermentation. The enzyme activity of 1.51 mU/mL and protein level of 0.205 mg/mL can be achieved. After numerical optimization, the fermentation process was verified in erlenmeyer flasks with incubator shaking at 77 rpm, initial pH 8, 37 °C, and 15 h fermentation. The verification results showed that the enzyme activity of 1.273 ± 0.227 mU/mL and protein level of 0.248 ± 0.012 mg/mL.  
Adsorption of Phosphate Ion in Water with Lithium-Intercalated Gibbsite
No full textIn order to enhance adsorption capacity of gibbsite (Al(OH)3 as an adsorbent for the adsorption of phosphate in water, gibbsite was modified through lithium-intercalation. The purification method of Tributh and Lagaly was applied prior to intercalation. The Li-Intercalation was prepared by the dispersion of gibbsite into LiCl solution for 24 hours. This intercalation formed an cationic clay with the structure of [LiAl2(OH)6]+ and exchangeable Cl- anions in the gibbsite interlayer. A phosphate adsorption test using Lithium-intercalated gibbsite (LIG) resulted in optimum adsorption occurring at pH 4.5 with an adsorption capacity of 11.198 mg phosphate/g LIG which is equivalent with 1.04 wt% LIG. The adsorption capacity decreased with decreasing amounts of H2PO4-/HPO4- species in the solution. This study showed that LIG has potential as an adsorbent for phosphate in an aqueous solution with pH 4.5–9.5
In Vitro Formation of 8-hydroxy-2-deoxyguanosine (8-OHdG) in Calf Thymus DNA upon Treatment of 2-deoxyguanosine with Propyl Gallate and 2,6-di-tert-butyl-p-benzoquinone
No full textOxidative DNA damage caused by propyl gallate (PG) and 2,6-di-tert-butyl-p-benzoquinone (BHT-quinone, a metabolite of butylated hydroxytoluene (BHT)) was analyzed from the 8-hydroxy-2¢-deoxyguanosine (8-OHdG) formation in calf thymus DNA and DNA base, 2¢-deoxyguanosine (dG). PG in the presence of CuCl2 increased the 8-OHdG formation in calf thymus DNA by around 9.17 times as compared to the control (untreated DNA). In the presence of CuCl2 at 1.28×10-5 M, the 8-OHdG per dG ratio resulting from the reaction of dG with PG at various concentrations (20–150 ppm) ranged from 75.50 to 312.06 8-OHdG per 105 dG. The 8-OHdG formation increased when the PG concentration was increased from 20 ppm to 80 ppm, and then, it began to plateau around 80 ppm. On the other hand, BHT-quinone increased the formation of 8-OHdG in the presence of CuCl2 by 0.05 times as compared to the control (untreated DNA). LC-MS/MS analysis was used to identify the molecular structure of 8-OHdG, which had a base peak (M+. + 1) at m/z = 284 and two main fragments at m/z = 167.9 and m/z = 139.9
Feeding Behavior of Tonkean Macaques (Macaca tonkeana) in Schmutzer Primates Center and Ragunan Zoo, Jakarta
No full textTonkean macaques are one of seven endemic macaque species on Sulawesi Island. Feeding management in captivity should pay attention to the quality, palatability, and feeding behavior patterns of animals. The goal of this study was to compare the feeding behavior of two social groups of Tonkean macaques at Schmutzer Primates Center (SPC) and Ragunan Zoo (RZ) with different captive management, which was expected to affect feeding behavior. Ad libitum sampling was used to observe daily behavior and hierarchy, while focal animal sampling was used to observe feeding behavior and feed preference. Data were collected from September 2013 until March 2014 with a total of 495 hours of observations. There were significant differences between the daily behavior of two groups of Tonkean macaques. Resting behavior was dominant in RZ group with non-enrichment feed cage, while feeding behavior was more common in the SPC group with an enrichment feed cage. The SPC group spent most of their feeding time in searching for feed, while choosing, carrying and refusing were greater in the RZ group. Both Tonkean macaque groups showed individual dominance in their feeding behavior. Provisioned feed in both locations had different diversity and preference values. The selection of feed required was based on preference values with attention to Tonkean macaques’ feed in nature. Cage construction, such as the SPC cage, was able to reduce abnormal behavior exhibited by individuals
Microwave-Assisted Synthesis of Alginate-Stabilized Gold Nanoparticles
No full textAn efficient and rapid method for preparation of Au nanoparticles (Au-NP) has been developed by direct microwave irradiation of metal precursor and alginate mixed solution in a single step. Here, alginate molecules act as both the reducing and stabilizing agents of Au-NP. The obtained nanoparticles were characterized by ultraviolet-visible (UV-Vis) spectroscopy, particle size analyzer, fourier transform infrared spectroscopy, and transmission electron microscopy. The nanoparticles have a spherical form and perfectly capped with alginate when using alginate and chloro auric acid (HAuCl4) precursor in the concentration range of 0.50 to 0.75% (w/v) and 0.40 mM, respectively. The use of a lower concentration of alginate and/or higher concentration of HAuCl4 caused agglomeration to occur, thereby resulting in a bigger size of Au-NP and red shifting of surface plasmon resonance (SPR) peak to a higher wavelength