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Agricultural Waste (agricultural + waste)
Selected AbstractsPenicillium strains as dominant degraders in soil for coffee residue, a biological waste unsuitable for fertilizationJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2007Katsuhiko Fujii Abstract Aims:, Coffee residue is an agricultural waste which inhibits the growth of several crops. Therefore coffee residue-degrading microbes in soil were screened, isolated and characterized. Methods and Results:, Forty isolates were obtained after enrichment culture of soil samples. Seven strains (fast degraders) showed strong degrading activity, while 18 strains (slow degraders) showed weak degrading activity. DNA analysis suggested that the fast degraders are Penicillium, and the slow degraders are Penicillium, Trichoderma/Hypocrea, Fusarium/Gibberella, Phaeoacremonium/Togninia or Acidocella. The all fast degraders are cellulolytic, mannolytic and pectinolytic. Conclusions:, Although it is generally thought that fungi such as Trichoderma contribute largely to aerobic degradation of cellulosic biomass, our data suggested that Penicillium overwhelms them in coffee residue degradation. It was implied that polysaccharides in coffee residue are not degraded independently by different microbes, but degraded simultaneously by strains with cellulolytic, mannolytic and pectinolytic activity. Since there is no report of an ascomycete possessing all the three enzyme activities, the fast degraders are ecologically important and have the potential to be used as producers of the costly enzymes from agricultural wastes. Significance and Impact of Study:, The present results advance our understanding of microbial degradation of a phytotoxic agricultural waste, and offer a new tool for recycling it. [source] Removal of heavy metals and cyanide from gold mine wastewaterJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2010Mike A. Acheampong Abstract This paper reviews the technology and biotechnology to remove heavy metals (such as copper, arsenic, lead and zinc) and cyanide from contaminated wastewater. The paper places special emphasis on gold mine wastewater and the use of low cost materials as sorbent. Various biological as well as physicochemical treatment processes are discussed and compared on the basis of costs, energy requirement, removal efficiency, limitations and advantages. Sorption using natural plant materials, industrial and agricultural waste has been demonstrated to have the potential to replace conventional methods for the removal of heavy metals because of its cost effectiveness, efficiency and the local availability of these materials as biosorbent. The parameters affecting sorption, such as initial ion concentration, pH, sorbent dosage, particle size and temperature, are discussed. The overall treatment cost of metal and cyanide contaminated wastewater depends on the process employed and the local conditions. In general, technical applicability, cost-effectiveness and plant simplicity are the key factors in selecting the most suitable treatment method. Copyright © 2010 Society of Chemical Industry [source] Preparation of bioadsorbents for effective adsorption of a reactive dye in aqueous solutionASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2010Shariff Ibrahim Abstract The surface of barley straw, an agricultural waste, was modified chemically using a cationic surfactant hexadecylpyridinium chloride monohydrate (CPC) and used as an adsorbent for removal of Reactive Blue 4 (RB4) from aqueous solution. The raw and surfactant-modified barley straws (SMBS) were characterized by Fourier transform infrared and elemental analysis. The stability of CPC adsorbed on straw surface was evaluated by exposing to water and organic solvents. The adsorption was performed on removing RB4 from wastewater in a batch adsorption system. The effects of contact time, initial concentration of dye and pH of solution on RB4 uptake were investigated and discussed. It was found that the removal percentage of RB4 increased with the increase in contact time. Adsorption was favorable at acidic condition and the maximum removal of 100% was obtained at pH 3. Dye-loaded SMBS was stable and percentage of desorption was less than 7% in water. The kinetic studies revealed that the kinetic data fitted well to the pseudo-second-order model. The isotherm study also indicated that RB4 adsorption on SMBS matched well with the Langmuir model other than the Freundlich model. The maximum adsorption capacity determined from the Langmuir isotherm was 29.2 mg g,1 at 25 °C. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Rice straw management: the big wasteBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 2 2010Laura Domínguez-Escribá Abstract Rice is one of the major foods, with consumption per capita of 65 kg per year, accounting for 20% of global ingested calories. Rice production is expected to increase significantly in the near future in order to feed the rising human population. Today, paddy rice culture produces 660 million tons of rice, along with 800 million dry tons of agricultural residues, mainly straw. This biomass is managed predominantly through rice straw burning (RSB) and soil incorporation strategies. RSB leads to significant air pollution and has been banned in some regions, whereas stubble and straw incorporation into wet soil during land preparation is associated with enhanced methane emissions. Therefore, both strategies have important deleterious environmental effects and fail to take advantage of the huge energy potential of rice straw. Using rice straw as lignocellulosic biomass to produce bioethanol would appear to be a promising and ambitious goal to both manage this agricultural waste and to produce environmentally friendly biofuel. Technical difficulties, however, associated with the conversion of lignocellulose into simple, fermentable sugars, have hampered the massive development of rice-straw-derived bioethanol. Recent technical advances in straw pre-treatment, hydrolysis and fermentation may, however, overcome these limitations and facilitate a dramatic turnover in biofuels production in the near future. Copyright © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] Penicillium strains as dominant degraders in soil for coffee residue, a biological waste unsuitable for fertilizationJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2007Katsuhiko Fujii Abstract Aims:, Coffee residue is an agricultural waste which inhibits the growth of several crops. Therefore coffee residue-degrading microbes in soil were screened, isolated and characterized. Methods and Results:, Forty isolates were obtained after enrichment culture of soil samples. Seven strains (fast degraders) showed strong degrading activity, while 18 strains (slow degraders) showed weak degrading activity. DNA analysis suggested that the fast degraders are Penicillium, and the slow degraders are Penicillium, Trichoderma/Hypocrea, Fusarium/Gibberella, Phaeoacremonium/Togninia or Acidocella. The all fast degraders are cellulolytic, mannolytic and pectinolytic. Conclusions:, Although it is generally thought that fungi such as Trichoderma contribute largely to aerobic degradation of cellulosic biomass, our data suggested that Penicillium overwhelms them in coffee residue degradation. It was implied that polysaccharides in coffee residue are not degraded independently by different microbes, but degraded simultaneously by strains with cellulolytic, mannolytic and pectinolytic activity. Since there is no report of an ascomycete possessing all the three enzyme activities, the fast degraders are ecologically important and have the potential to be used as producers of the costly enzymes from agricultural wastes. Significance and Impact of Study:, The present results advance our understanding of microbial degradation of a phytotoxic agricultural waste, and offer a new tool for recycling it. [source] Bioleaching of copper and other metals from low-grade oxidized mining ores by Aspergillus nigerJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2003Catherine N Mulligan Abstract A study was initiated to determine the feasibility of using the fungus Aspergillus niger for bioleaching metals from oxide low-grade ore. Large quantities of the metals are embodied in the low-grade ores and mining residues that can be recovered. Presently available techniques (pyrometallurgical and hydrometallurgical) are expensive or may have a negative impact on the environment. An oxidized mining ore containing mainly copper (7245 mg kg,1 residue) was studied. In this study, the fungus A niger produced a variety of organic acids. Addition of small quantities of sulfuric acid enhanced the organic acids, efficiency. Various agricultural wastes were evaluated as substrates and a maximum solubilization of 68% for copper for a medium containing potato peels was achieved. In conclusion, leaching of copper from a mining ore is technically feasible using A niger. Further research must be performed to increase the rate of copper removal. Copyright © 2003 Society of Chemical Industry [source] | ||||||||||