Continuous Production Of Organic Acids From Palm Oil Mill Effluent And Kitchen Garbage

Waste materials such as palm oil mill effluent (POME) and kitchen garbage or refuse can be used as raw materials for organic acids production. In this study, POME and blended kitchen garbage were separately fed continuously into an anaerobic fermentation system in which they were converted to organic acids namely acetic, propionic, butyric and lactic acids, depending on the experimental conditions and type of microorganisms involved in the anaerobic treatment. The effect of two types of neutralizer, CaC03 and NaOH, on anaerobic treatment of POME was examined. The POME treatment was stabilized at pH5.0-5.5 when CaC03 was used to adjust the pH. Subsequently, anaerobic treatment of POME was performed at pH 5.0-5.5 with sludge recycle system. The major organic acids produced were acetic (5.0-5.6 g/L), propionic (2.0-2.6 g/L) and butyric acids (2.3- 3.3 g/L). Higher amount of butyric acid (average 2.8 g/L) was produced at pH 5.0. The sludge solids in the treated POME were separated by freezing-thawing technique and recycled into the reactor. More than 87% of the suspended solids in the treated POME were removed by this method.However, the clarified solution still contained more than 20,000 mg/L of total solids. Total microbial population stabilized at 108 cfu/mL in the reactor but reduced to 106 cfu/mL in the dewatered sludge upon freezing and thawing. The organic acids were fractionated to obtain more concentrated organic acids (22.4 g/L). In the case of kitchen garbage, Lactobacillus rhamnosus converted the carbohydrates to lactic acid with more than 87% selectivity. Glucoamylase with the activity of 60 U/mg was added during the fermentation at a dosage of 300 mg/L to enhance the hydrolysis of organic materials. Three sets of experimental conditions were studied, i.e. at pH 6.8 with RT 5 days, pH 5.5 with RT 5 days and pH 5.5 with RT 2.5 days which produced an average lactic acid concentration of 42 g/L, 53 g/L and 50 g/L respectively. The residual glucose and total sugars at steady state were less than 1 g/L and 20 g/L respectively. The optical purity of Llactic acid obtained was more than 90% under the optimum condition of pH 5.5 with RT 2.5 days

Treatment of wastewater from rubber industry in Malaysia

Presently, Malaysia is the third largest rubber producer in the world, whereby the rubber industry is an economically and socially significant industry. Rubber industry consumes large volumes of water, uses chemicals and other utilities and produces enormous amounts of wastes and effluent. Discharge of untreated rubber effluent to waterways resulted in water pollution that affected the human health. With a new global trend towards a sustainable development, the industry needs to focus on cleaner production technology, waste minimization, utilization of waste, resource recovery and recycling of water. The present work aims at highlighting various technologies that currently have been used for treatment of rubber effluent in Malaysia. The work introduces the basis of these processes including their benefits and also problems. It also adheres to the future trends of rubber effluent treatment in Malaysia by reviewing various treatment technologies for natural rubber industry implemented by Thailand, the world largest rubber producer. These new and effective effluent treatment methods would minimize environmental pollution of rubber industry and bring it to become sustainable and environmental friendly

Acetone–butanol–ethanol production by Clostridium acetobutylicum ATCC 824 using sago pith residues hydrolysate

Sago pith residues (58 % starch, 23 % cellulose, 9.2 % hemicellulose, and 4 % lignin) are one of the abundant lignocellulosic residues generated after starch extraction process in sago mill. In this study, fermentable sugars from enzymatic hydrolysis of sago pith residues were converted to acetone–butanol–ethanol (ABE) by Clostridium acetobutylicum ATCC 824. With an initial concentration of 30 g/L of concentrated sago pith residues hydrolysate containing 23 g/L of glucose and 4.58 g/L of cellobiose, 4.22 ± 0.17 g/L of ABE were produced after 72 h of fermentation with yield and productivity of 0.20 g/g glucose and 0.06 g/L/h, respectively. Results are in agreement when synthetic glucose was used as a carbon source. Increasing sago pith residue hydrolysate to 50 g/L (containing 40 g/L glucose) and supplementing with 0.5 g/L yeast extract, approximately 8.84 ± 0.20 g/L of ABE (5.41 ± 0.10 g/L of butanol) were produced with productivity and yield of 0.12 g/L/h and 0.30 g/g glucose respectively, providing a 52 % improvement

Treatments of chicken feather waste

Feather waste is a potential renewable source to recover valuable products because it is being a rich source of keratin proteins and amino acids. It can be used to make feather meal, fertilizer and yarn sizing agent. Various treatments have been used to recover the protein from chicken feathers as the keratinous feathers cannot be easily degraded due to its tough structure. This paper reviews the existing treatment methods used to hydrolyze chicken feathers. The treatment methods for feather hydrolysis such as physical, chemical, biological and combined treatments as well as their advantages and challenges are highlighted. The effects of these treatments on feather hydrolysis are complex and vary in regards to the performance of feather hydrolysis and product yielded. Hence, it is important to choose an appropriate treatment method since the type of treatment applied affects the product yielded qualitatively and quantitatively. In addition, the economic assessment and environmental impact of the choice of treatment should be considered also

Optimization of metallo-keratinase production by Pseudomonas sp. LM19 as a potential enzyme for feather waste conversion

Locally isolated bacterium Pseudomonas sp. LM19, a metallo-keratinase producer was used to hydrolyze the highly rigid keratin recalcitrant in this study. The production of crude keratinase by Pseudomonas sp. LM19 is influenced by both physical and nutritional parameters. The highest keratinase activity of 127 U/ml (2.15-fold) was observed in feather meal medium supplemented with fructose and peptone at a C/N ratio of 40. The optimum pH and temperature for keratinase production were found to be pH 8 and 30 °C, using 1% (w/v) feather as substrate. The degradation rate of the feathers was increased 2.4-fold at optimized physical and nutritional conditions. Feather degradation by Pseudomonas sp. LM19 led to the production of free amino acids such as arginine, glycine, leucine, and serine. The information on the production of keratinase by Pseudomonas sp. LM19 obtained from this study warrants further research for possible commercial application

Sustainable production of polyhydroxyalkanoates from renewable oil-palm biomass

With rapid industrialization and increasing per-capita consumption of conventional plastics, there is a growing need for the development of bio-based materials from renewable resources to reduce the environmental footprint of plastic production. Oil palm biomass, which is the largest biomass in Malaysia, has tremendous potential as a primary or secondary feedstock for polyhydroxyalkanoate (PHA) production. PHA production can be made more competitive and sustainable by using oil palm biomass effluent and residues that are available at the factories. The oil palm biomass as non-food biomass from the mill is a great strategy towards zero discharge in palm oil industry by combining wastewater treatment system for mixed organic acids production together with PHA production from the clarified organic acids. Hence, several oil palm biomass have been explored and considered as sustainable promising sources for PHA production in future. Solid waste such as oil palm frond and oil palm empty fruit bunch can be used as sugar based substrate. In addition, palm oil mill effluent can be effectively converted to mixed organic acids and glycerol as wastes from palm oil based biodiesel processing plant are suitable for PHA production. The successful bioconversion and utilization of oil palm biomass can reduce the production costs of PHAs and minimize greenhouse-gas emissions. This article provides an overview of various types of biomass generated by the palm oil industry and describes their bioconversion into PHAs by various PHA producers. Future perspectives and challenges for the commercialization of PHAs produced using oil palm biomass are also discussed

Adsorption of vanillin using macroporous resin H103

Six resins (Amberlite XAD-16, Amberlite XAD-2, Sepabeads SP207, DIAION HP-20, DM11 and H103) were tested for vanillin adsorption in aqueous solution. All of the resins gave more than 95% adsorption rate except for Amberlite XAD-2 and DM11. Resin H103 was selected for the subsequent work due to its high adsorption capacity and low cost. A kinetic analysis revealed that the adsorption process followed pseudo-second-order kinetic model and occurred rapidly. The equilibrium point was reached after 90 minutes of reaction. Adsorption isotherm was also determined at 25 °C and it was fitted to Langmuir and Freundlich equations using linear regression and non-linear regression (sum of squares) methods. The regression shows that the adsorption of vanillin onto resin H103 followed Langmuir model (R2 = 0.9984) with a maximum capacity of 73.015 mg/g

Effect of physical and chemical properties of oil palm empty fruit bunch, decanter cake and sago pith residue on cellulases production by Trichoderma asperellum UPM1 and Aspergillus fumigatus UPM2

The effect of cultivation condition of two locally isolated ascomycetes strains namely Trichoderma asperellum UPM1 and Aspergillus fumigatus UPM2 were compared in submerged and solid state fermentation. Physical evaluation on water absorption index, solubility index and chemical properties of lignin, hemicellulose and cellulose content as well as the cellulose structure on crystallinity and amorphous region of treated oil palm empty fruit bunch (OPEFB) (resulted in partial removal of lignin), sago pith residues (SPR) and oil palm decanter cake towards cellulases production were determined. Submerged fermentation shows significant cellulases production for both strains in all types of substrates. Crystallinity of cellulose and its chemical composition mainly holocellulose components was found to significantly affect the total cellulase synthesis in submerged fermentation as the higher crystallinity index, and holocellulose composition will increase cellulase production. Treated OPEFB apparently induced the total cellulases from T. asperellum UPM1 and A. fumigatus UPM2 with 0.66 U/mg FPase, 53.79 U/mg CMCase, 0.92 U/mg β-glucosidase and 0.67 U/mg FPase, 47.56 U/mg and 0.14 U/mg β-glucosidase, respectively. Physical properties of water absorption and solubility for OPEFB and SPR also had shown significant correlation on the cellulases production

Laccase enzyme production by Pycnoporus sanguineus using oil palm empty fruit bunch as substrate

Laccase is one of the ligninolytic enzymes along with manganese peroxidase and lignin peroxidase. The biotechnological use of laccase has been widely applied in various field ranging from discoloration of textile dye effluent, pulp and paper processing, removal of phenolics from wine and many more. The white rot basidiomycete fungus Pycnoporus sanguineus is reported to be one of the most prominent laccase producers. Over the last few decades, many efforts have been done to improve the laccase enzyme production. The addition of inducer is expected to increase the laccase production as it will induce high expression of laccase gene by the fungus. Different types of inducer which are veratryl alcohol, copper sulfate, 2,5-xylidine and ferulic acid were investigated in this study using oil palm empty fruit bunch (OPEFB) as substrate in a submerged fermentation condition. Each inducer was added at certain concentration into the enzyme production medium using one factor at a time approach. An increase in laccase enzyme activity was observed with the addition of inducer into the basal medium. Hence, laccase production by Pycnoporus sanguineus can be improved with the addition of inducer

Rapid screening method for isolation of glycerol-consuming bacteria for ethanol production

Large numbers of glycerol-consuming bacteria are present in nature; hence bioconversion of glycerol into biofuel which is bioethanol is one of the interests. The effective screening procedure is needed to screen and isolate broad ranges of bacteria from environment. The screening method was modified based on enzymatic oxidation of ethanol, which is correlated to reduction of 2,6-dichlorophenol-indophenol dye that resulted in the formation of yellow zone. Approximately 300 colonies were able to grow on minimal media using glycerol as sole carbon. Only about 70 isolates showed positive result when using the modified ethanol production assay after pre-screening stage. The formation of decolourized zone was apparent using modified assay containing 5 mL/L of 0.05M 2,6-dichlorophenol-indophenol, 10 mL of reaction mixture and 500 μl/L of enzyme, respectively. The ethanol production capability of the isolates was further proven by anaerobic fermentation as a quantitative method. This modified method is applicable in screening for ethanol producer from glycerol as carbon source allows rapid and more bacteria can be screened