Comparison on decolorization of palm oil mill effluent by biological, chemical and physical methods

Decolorization of palm oil mill effluent pretreated by enzyme from Aspergillus niger ATCC 6275 was investigated. The culture filtrate after separation of suspended solids was used for decolorization by biological, chemical and physical methods. Results indicated that the chemical method (using coagulant) was more effective than the biological method (using commercial peroxidase, two strains of white-rot fungi Phanerochaete chrysosporium and Coriolus versicolor) and physical method (using activated carbon, pararubber seed and sand filter). Studies on the effect of coagulant concentrations on decolorization revealed that using the combination of 10 ml/l polyferric sulphate and 10 g/l calcium oxide gave the highest color removal of 84.5% and organic matter (in term of chemical oxygen demand, COD) removal of 86.5%

The application of fluorescence in situ hybridization (FISH) technique for studying the microbial communities in intestinal tissues of white shrimp (Penaeus vannamei)

Fluorescence in situ hybridization technique is very useful for the evaluation of microbial communities in various environments. It is possible to apply this technique to study the intestinal microflora in white shrimp (Penaeus vannamei). Different fixatives and storage temperature were tested in this technique. It was found that fixation with 10% buffered formalin for 12 hours and changed to 70% ethanol shown positive results when compared to the fixation with Davidson's fixative or RF fixative. The best signaling was obtainedfrom the samples which were stored in -20ºC. By using the DNA probe targeted to the Eubacteria domain (EUB338 probe, 5′-GCT GCC TCC CGT AGG AGT-3′) labeled with fluorescein as a hybridizing probe, it was found that most intestinal microflora were aggregated with the intestinal contents, or dispersed in the lumen. There was not evidence of the attachment of the microflora with the intestinal epithelium in this study

Thermodynamic analysis of methanation of palm empty fruit bunch (PEFB) pyrolysis oil with and without in situ CO2 sorption

Thermodynamic equilibrium analysis for conversion of palm empty fruit bunch (PEFB) bio-oil to methane using low-temperature steam reforming (LTSR) process was conducted by assuming either isothermal or adiabatic condition, with and without sorption enhancement (SE-LTSR), with CaO(S) or Ca(OH)2(S) as CO2 sorbent. Temperatures of 300-800 K, molar steam to carbon (S/C) ratios of 0.3-7.0, pressures of 1-30 atm and molar calcium to carbon ratios (Ca:C) of 0.3-1.0 were simulated. For reasons of process simplicity, the best conditions for CH4 production were observed for the adiabatic LTSR process without sorption at S/C between 2.5 and 3 (compared to the stoichiometric S/C of 0.375), inlet temperature above 450 K, resulting in reformer temperature of 582 K, where close to the theoretical maximum CH4 yield of 38 wt % of the simulated dry PEFB oil was obtained, resulting in a reformate consisting of 44.5 vol % CH4, 42.7 vol % CO2 and 12.7 vol % H2 and requiring only moderate heating mainly to partially preheat the reactants. Temperatures and S/C below these resulted in high risk of carbon by-product

Bio-composting oil palm waste for improvement of soil fertility

Sources of bio-compost as agro-industrial wastes includes wide range of oil palm wastes viz. waste, biomass, palm kernels, empty fruit bunch, mill effluent, trunk and frond compost. Various composting processes are summarized in brief with distinct reference of oil–palm composting covering aerated static pile, and co-composting with earthworms (vermicomposting). However, in-vessel composting and windrow composting has meritorious advantages in composting. This review article refers to various significant roles played by microorganisms associated. Noteworthy study of bio-compost applications and procedures are correspondingly glosses framework of ecological, economical and agro-ecosystemic benefits

Nutrient optimization for cellulase biosynthesis by a newly isolated Cellulomonas sp.

A cellulolytic bacterium has been isolated from soil and identified as a Cellulomonas sp. Optimization of media components and environmental factors led to a 17-fold increase in cellulase activity within 40 h. The trace elements Zn2+, Co2+ and Cu2+ caused severe inhibition, which could be reduced by the addition of EDTA. The enzymes endoglucanase, exoglucanase and xylanase were always present irrespective of the carbon source used

Screening and characterization of bioflocculant produced by isolated Klebsiella sp

Sixteen strains of polymer-producing bacteria were isolated from the activated sludge samples taken from two seafood processing plants in Southern Thailand. Their culture broths possessed the ability to flocculate kaolin suspension in the presence of 1% CaCl. Based on the flocculating activity, the strain S11 was selected and identified to be a Klebsiella sp. using the partial 16S rRNA sequencing method. The growth of the isolated Klebsiella sp. was maximal (1.026 g l dry cell mass) after 1 day cultivation while the highest polymer yield (0.973 g l) was achieved after 5 days cultivation. The flocculating activity of the culture broth, however, was highest after 2 days cultivation. The polymer was identified to be an acidic polysaccharide containing neutral sugar and uronic acid as its major and minor components, respectively. Results on the properties of the partially purified polysaccharide from Klebsiella sp. S11 revealed that it consisted of galactose, glucose and mannose in an approximate ratio of 5:2:1. It was soluble in acidic or basic solutions but not in organic solvents. Its molecular mass was greater than 2 x 10 Da. Infrared spectra showed the presence of hydroxyl, carboxyl and methoxyl groups in its molecules. Differential scanning calorimetry of the polysaccharide indicated the crystalline melting point (T(m)) at 314 °C. The optimum dosage of polysaccharide to give the highest flocculating activity was 15 mg l in the presence of 1% CaCl