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Setiyo Gunawan Syahrizal MaulanaKhairiel Anwar Tri Widjaja 《Industrial Crops and Products》2011,33(3):624-628
Biodiesel is a biodegradable, renewable, non-toxic and environmentally friendly alternative fuel. The cost of raw materials comprises 60-88% of the production cost in commercial biodiesel (fatty acid methyl esters, FAMEs) production. Therefore, the use of low-cost raw material as a substrate and an in situ process for biodiesel production are being preferred. In this case, rice bran, which contains 13.5% oil, was an interesting substrate. In situ esterification of high-acidity rice bran with methanol and sulfuric acid catalyst was investigated. The individual and interaction effects of methanol to rice bran ratio, sulfuric acid catalyst concentration and reaction time on purity and recovery of biodiesel were discussed. Our results suggest that under the following operation conditions: methanol to rice bran ratio of 5 mL/g, sulfuric acid concentration in methanol of 1.5 vol.%, and reaction time of 60 min, an in situ esterification operated on rice bran could yield FAMEs with a high purity and recovery. By applying an in situ esterification with n-hexane/water extractions, Indonesia will be succesfull in obtaining biodiesel from rice bran up to 96,000 ton per year. 相似文献
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Method for analysis of fatty acid distribution and oil content on a single Lesquerella fendleri seed
Terry A. Isbell Melissa S. Mund Roque L. Evangelista David A. Dierig 《Industrial Crops and Products》2008,28(2):231-236
Lesquerella fendleri is a developing oilseed crop suitable for temperate growing regions in the US. The seed oil is rich in lesquerolic acid (57%) and could serve as a domestic source of hydroxy fatty acids. A method for the analysis of fatty acids and total oil content of a half or single lesquerella seed was developed. Lesquerella seeds are small with 1000 seed weights around 0.6 g (half seed mass of 200–500 μg). Conventional analytical balances provide mass accuracy to ±40 μg which fails to provide sufficient accuracy/precession (4–40% mass error) for the initial seed mass. A microbalance which measures to ±2 μg provided good reproducibility in initial seed weights but was not suitable for mass balance of the extracted oil. A normal phase HPLC coupled to an evaporative light scattering detector gave good response for oil in the mass range of 22 μg to 110 μg/mL. Therefore, micelle concentrations from single or half seed extractions could be determined with good reproducibility. This method was then evaluated on bulk seed that had been fractionated on a gravity table. Gravity table fractionation of L. fendleri seeds obtained from a large field plot provided seven fractions with increasing bulk density. These fractions were then analyzed in sets of 30 individual seeds and as an aggregate of 50 seeds. Oil content for individual seeds varied widely (15.6–44.2%) as did lesquerolic acid content (42.2–63.7%). The mean oil content increased (27–33%) with increasing bulk density (684–745 g/L). The mean lesquerolic acid content did not correlate with bulk density. 相似文献
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Formation of ridges during row cultivation creates microsites that could enhance spatial heterogeneity of soil properties, such as organic C, and thereby influence soil microbial communities. A study was conducted during 2003 near Shelton, NE, on a corn (Zea mays L.) field mapped using apparent electrical conductivity (ECa). New ridges were built each year with a row cultivator when corn reached the V3–V4 growth stage. Cultivation increased labile C fractions and soil microbial biomass in the row position for all ECa classes. Canonical discrimination analysis showed no clear differences in relative abundance of specific microbial groups among ECa classes or between row and furrow position, except for enhanced mycorrhizal biomass in the row. Microbial biomass responded strongly to changes in C redistribution, but was not accompanied by a significant change in the abundance of specific microbial groups. Labile C fractions (coarse and fine particulate organic matter) and crop residues in diverse stages of decomposition are associated with diverse microbial groups. Thus, row cultivation for weed control creates a biologically enhanced root zone that may improve early season performance of corn. 相似文献
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Arbuscular mycorrhizal (AM) fungi are recognized for their positive effects on plant growth, playing an important role in plant P nutrition. We used C16:1cis11 and C18:1cis11 fatty acid methyl ester (FAME) biomarkers to monitor the dynamics of AM fungi during the reproductive stages of maize (Zea mays L.) grown at high yield in Nebraska, USA. Two fields with four different levels of P availability were sampled throughout the reproductive stages. Chambers, made of PVC enclosed mesh fabric to allow passage of roots and hyphae (+R) or hyphae alone (-R) and amended with either KH2PO4(+P) or distilled water (-P), were installed in the field at tasselling and removed after three, six and nine weeks. Our objectives were (i) to provide evidence for C allocation to AM fungi during the reproductive stages of high productivity maize and (ii) to link AM fungal growth dynamics with changes in soil P availability. We observed that initial AM FAME concentration was lower at sites with a high availability of P. During the reproductive growth of maize, AM biomarkers increased inside the chambers and were consistent with the biomarker increase observed in adjacent field soil. This confirms that there is C allocation from the plant to the symbiont during the reproductive stages of maize. We also observed a reduction in available P in +R and -R chambers. This observation implies that hyphae were as efficient as roots and hyphae in reducing the P concentration in chambers. These results demonstrate that AM fungi are active during the reproductive growth stages of maize and may benefit high productivity maize crops by facilitating P uptake. 相似文献
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Nowadays, lots of efforts are made in Tunisia for the exploitation of wastewater in agriculture in order to face a very elevated mobilization of resources in water (90%). At Sfax, a Governorate placed in the South of Tunisia, the annual rainfall rarely exceeds 200 mm, so the climate is fairly arid. The significant water deficit can be reduced with the reuse of treated wastewater (TWW). The Sfax wastewater originated from the municipal wastewater treatment plant (WWTP) localized at 5 km in the south of Sfax, Tunisia. This WWTP is an aerated lagoon process receiving industrial wastewaters. Its treatment capacity is 24,000 m3/day. Part of TWW is sent to the olive crops of El Hajeb, as part of a proposed wastewater use in agriculture. Already the wastewater is used to irrigate olive trees and intercrops such as cotton, oats and sorghum silage (Charfi et al., 1999). The aim of the present work was to determine the impact of the irrigation utilizing wastewater on the quality of the oil. The oils analysed were extracted from olives hand-picked directly from the tree and from olives that have fallen under the trees. Moreover, a study on the olive storage has been made in order to evaluate in which way the collection of the fruit could influence the quality of the oil. 相似文献
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J. D. Janse † M. P. Rossi R. F. J. Gorkink J. H. J Derks J. Swings D. Janssens M. Scortichini 《Plant pathology》2001,50(6):653-665
A new bacterial disease of strawberry is described. This disease, called bacterial leaf blight of strawberry, is characterized by dry, brown necrotic leaf spots and large brown V-shaped lesions along the leaf margin, midrib and major veins. Symptoms are different from angular leaf spot of strawberry caused by the bacterium Xanthomonas fragariae . Strains of the bacterial leaf blight pathogen were characterized in a polyphasic approach by biochemical tests, fatty acid analysis, protein electrophoresis, serology, PCR, pigment analysis, ice-nucleation activity, AFLP analysis, DNA:DNA hybridization, pathogenicity and host range tests, and compared with a number of reference strains of X. fragariae and other Xanthomonas species. Bacterial leaf blight strains formed a homogeneous group in all tests, completely different from X. fragariae . They were the only strains causing leaf blight of strawberry upon artificial inoculation into strawberry. Fatty acid and protein electrophoretic analysis showed that the strains belong to the phenon X. campestris ( sensu latu , including pathovars now classified as belonging to X. arboricola ). AFLP analysis and DNA:DNA hybridization further clarified their taxonomic position as belonging to X. arboricola. The name X. arboricola pv. fragariae is proposed for the bacterium causing leaf blight of strawberry with strain PD2780 (LMG 19145) as pathovar type strain. Criteria for routine identification are given and the taxonomic status is discussed. 相似文献
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