Rice yield is still low in Nigeria despite the ecological advantages. Several challenges has been traced it production. The study intend to investigate if other rice producing nations are faced with similar challenges...Rice yield is still low in Nigeria despite the ecological advantages. Several challenges has been traced it production. The study intend to investigate if other rice producing nations are faced with similar challenges and at what magnitude and more importantly, what can be learn to improve the rice yield in Nigeria. Based on 2013/2014 survey, a total sample of 400 famers were randomly interviewed;164 from Niger State of Nigeria and 236 from Hainan province of China. The study collate the perception of farmers to rice production constraints categorized into biotic, abiotic and socioeconomics. Biplot analysis was employed to examine multivariate pattern of their perceptions towards production constraints. The multivariate technique simultaneously displaying different yield levels and factor constraints in data matrix providing the inter-unit distances, variance and correlations of variables. According to the study, Niger state farmers identified socioeconomic constraint as the major factors to production and attributed it to lack of or insufficient investment while the Hainan farmers majorly identified abiotic constraints. The study also indicated that great potential remain to further improve rice yield in both regions especially in Nigeria given the appropriate investment on essential inputs. This study is of great use to extension officers more so, given the investment in Africa, policy makers take advantage of the bilateral and multilateral relationship to invest ease transfer of agricultural information and technologies between or among partners.展开更多
Background： Rapeseed cake is a good source of protein for animal feed but its utilization is limited due to the presence of anti-nutritional substances, such as glucosinolates （GIs）, phytic acid, tannins etc. In th...Background： Rapeseed cake is a good source of protein for animal feed but its utilization is limited due to the presence of anti-nutritional substances, such as glucosinolates （GIs）, phytic acid, tannins etc. In the present study, a solid state fermentation （SSF） using Aspergillus niger was carried out with the purpose of degrading glucosinolates and improving the nutritional quality of rapeseed cake （RSC）. The effects of medium composition and incubation conditions on the GIs content in fermented rapeseed cake （FRSC） were investigated, and chemical composition and amino acid in vitro digestibility of RSC substrate fermented under optimal conditions were determined. Results： After 72 h of incubation at 34℃, a 76.89% decrease in GIs of RSC was obtained in solid medium containing 70% RSC, 30% wheat bran at optimal moisture content 60% （w/w）. Compared to unfermented RSC, trichloroacetic acid soluble protein （TCA-SP）, crude protein and ether extract contents of the FRSC were increased （P〈 0.05） 103.71, 23.02 and 23.54%, respectively. As expected, the contents of NDF and phytic acid declined （P〈 0.05） by 9.12 and 44.60%, respectively. Total amino acids （TAA） and essential amino acids （EAA） contents as well as AA in vitro digestibility of FRSC were improved significantly （P 〈 0.05）. Moreover, the enzyme activity of endoglucanase, xylanase, acid protease and phytase were increased （P 〈 0.05） during SSF. Conclusions： Our results indicate that the solid state fermentation offers an effective approach to improving the quality of proteins sources such as rapeseed cake.展开更多
The production of citric acid using Chrysophyllum albidum an indigenous under-utilized fruit waste peel and genetically characterized strains of Aspergillus niger was carried out. The Chrysophyllum albidum peel was dr...The production of citric acid using Chrysophyllum albidum an indigenous under-utilized fruit waste peel and genetically characterized strains of Aspergillus niger was carried out. The Chrysophyllum albidum peel was dried, sieved to remove dirt, dry milled and the powder used as substrate for citric acid production. Thirteen fungal isolates were obtained from soil samples and decayed agricultural waste by spread plate technique and screened for citric acid producing capabilities on Czapek dox agar. Citric acid producing capability of the isolates revealed a wide yellow zone around the inoculated colonies. Two (F1 and F3) out of the thirteen isolates exhibited positive reactions and were identified based on their cultural, morphological and molecular characteristics. The fungal species were identified using PCR as Aspergillus niger DTO: 133-E8 and Aspergillus niger DTO: 131-H5. Their cultural/growth optimal conditions were determined through Solid State Fermentation of the substrate using two species of the test organism. The effects of fermentation period examined revealed, Aspergillus niger DTO: 133-E8 which produced the highest amount of citric acid 15.7 ± 0.08 g/l, lower reducing sugar and final pH of 2.1 and 121.5 ± 0.31 g/l respectively after 192 h of growth at 30°C. Aspergillus niger DTO: 131-H5 showed highest amount of citric acid 10.2 ± 0.22 g/l, lower reducing sugar and final pH of 2.4 and 128.5 ± 0.15 g/l respectively after 192 h of growth at 30°C. Maximum concentration of citric acid ranging between 16.3 ± 0.30 g/l and 12.6 ± 0.11 g/l with reducing sugar 125.4 ± 0.11 g/l and 127.2 ± 0.03 g/l was achieved at an initial pH of 5.5. Methanol was used to stimulate citric acid production (0% - 3% (v/v)) and was found to be effective at 2% (v/v) level with 21.2 ± 0.20 g/l of citric acid produced with residual sucrose concentration of 129.5 ± 0.44 g/l. The effect of trace element on citric acid production showed that Cu2+ and Fe2+ stimulated citric acid production;while other ions reduced citric acid production. There was a statistically significant difference (P > 0.05) between the citric acid produced with the various parameters investigated in this research. From the study, it has been found that Chrysophlum albidum is suitable for the cultivation of Aspergillus niger and has great potential for citric acid production and could be exploited to promote certain industrial applications of underutilized fruits in Nigeria. This can be an application of waste to wealth as well as a way of minimizing agro-based environmental pollution for a cleaner environment.展开更多
The influence of the physical structure of polyurethane matrix as a support in a solid state culture in tannase production and gallic acid accumulation by Aspergillus niger Aa-20 was evaluated. Three different polyure...The influence of the physical structure of polyurethane matrix as a support in a solid state culture in tannase production and gallic acid accumulation by Aspergillus niger Aa-20 was evaluated. Three different polyurethane matrices were used as the support: continuous, semi-discontinuous and discontinuous. The highest tannase production at 2479.59 U/L during the first 12 h of culture was obtained using the discontinuous matrix. The gallic acid was accumulated at 7.64 g/L at the discontinuous matrix. The results show that the discontinuous matrix of polyurethane is better for tannase production and gallic acid accumulation in a solid state culture bioprocess than the continuous and semi-discontinuous matrices.展开更多
文摘Rice yield is still low in Nigeria despite the ecological advantages. Several challenges has been traced it production. The study intend to investigate if other rice producing nations are faced with similar challenges and at what magnitude and more importantly, what can be learn to improve the rice yield in Nigeria. Based on 2013/2014 survey, a total sample of 400 famers were randomly interviewed;164 from Niger State of Nigeria and 236 from Hainan province of China. The study collate the perception of farmers to rice production constraints categorized into biotic, abiotic and socioeconomics. Biplot analysis was employed to examine multivariate pattern of their perceptions towards production constraints. The multivariate technique simultaneously displaying different yield levels and factor constraints in data matrix providing the inter-unit distances, variance and correlations of variables. According to the study, Niger state farmers identified socioeconomic constraint as the major factors to production and attributed it to lack of or insufficient investment while the Hainan farmers majorly identified abiotic constraints. The study also indicated that great potential remain to further improve rice yield in both regions especially in Nigeria given the appropriate investment on essential inputs. This study is of great use to extension officers more so, given the investment in Africa, policy makers take advantage of the bilateral and multilateral relationship to invest ease transfer of agricultural information and technologies between or among partners.
基金granted by the Earmarked Fund for Modern Agro-industry Technology Research System of China(CARS-36)Feed Biotechnology Project of Sichuan Province of China with grant number 2010GZ0193
文摘Background： Rapeseed cake is a good source of protein for animal feed but its utilization is limited due to the presence of anti-nutritional substances, such as glucosinolates （GIs）, phytic acid, tannins etc. In the present study, a solid state fermentation （SSF） using Aspergillus niger was carried out with the purpose of degrading glucosinolates and improving the nutritional quality of rapeseed cake （RSC）. The effects of medium composition and incubation conditions on the GIs content in fermented rapeseed cake （FRSC） were investigated, and chemical composition and amino acid in vitro digestibility of RSC substrate fermented under optimal conditions were determined. Results： After 72 h of incubation at 34℃, a 76.89% decrease in GIs of RSC was obtained in solid medium containing 70% RSC, 30% wheat bran at optimal moisture content 60% （w/w）. Compared to unfermented RSC, trichloroacetic acid soluble protein （TCA-SP）, crude protein and ether extract contents of the FRSC were increased （P〈 0.05） 103.71, 23.02 and 23.54%, respectively. As expected, the contents of NDF and phytic acid declined （P〈 0.05） by 9.12 and 44.60%, respectively. Total amino acids （TAA） and essential amino acids （EAA） contents as well as AA in vitro digestibility of FRSC were improved significantly （P 〈 0.05）. Moreover, the enzyme activity of endoglucanase, xylanase, acid protease and phytase were increased （P 〈 0.05） during SSF. Conclusions： Our results indicate that the solid state fermentation offers an effective approach to improving the quality of proteins sources such as rapeseed cake.
文摘The production of citric acid using Chrysophyllum albidum an indigenous under-utilized fruit waste peel and genetically characterized strains of Aspergillus niger was carried out. The Chrysophyllum albidum peel was dried, sieved to remove dirt, dry milled and the powder used as substrate for citric acid production. Thirteen fungal isolates were obtained from soil samples and decayed agricultural waste by spread plate technique and screened for citric acid producing capabilities on Czapek dox agar. Citric acid producing capability of the isolates revealed a wide yellow zone around the inoculated colonies. Two (F1 and F3) out of the thirteen isolates exhibited positive reactions and were identified based on their cultural, morphological and molecular characteristics. The fungal species were identified using PCR as Aspergillus niger DTO: 133-E8 and Aspergillus niger DTO: 131-H5. Their cultural/growth optimal conditions were determined through Solid State Fermentation of the substrate using two species of the test organism. The effects of fermentation period examined revealed, Aspergillus niger DTO: 133-E8 which produced the highest amount of citric acid 15.7 ± 0.08 g/l, lower reducing sugar and final pH of 2.1 and 121.5 ± 0.31 g/l respectively after 192 h of growth at 30°C. Aspergillus niger DTO: 131-H5 showed highest amount of citric acid 10.2 ± 0.22 g/l, lower reducing sugar and final pH of 2.4 and 128.5 ± 0.15 g/l respectively after 192 h of growth at 30°C. Maximum concentration of citric acid ranging between 16.3 ± 0.30 g/l and 12.6 ± 0.11 g/l with reducing sugar 125.4 ± 0.11 g/l and 127.2 ± 0.03 g/l was achieved at an initial pH of 5.5. Methanol was used to stimulate citric acid production (0% - 3% (v/v)) and was found to be effective at 2% (v/v) level with 21.2 ± 0.20 g/l of citric acid produced with residual sucrose concentration of 129.5 ± 0.44 g/l. The effect of trace element on citric acid production showed that Cu2+ and Fe2+ stimulated citric acid production;while other ions reduced citric acid production. There was a statistically significant difference (P > 0.05) between the citric acid produced with the various parameters investigated in this research. From the study, it has been found that Chrysophlum albidum is suitable for the cultivation of Aspergillus niger and has great potential for citric acid production and could be exploited to promote certain industrial applications of underutilized fruits in Nigeria. This can be an application of waste to wealth as well as a way of minimizing agro-based environmental pollution for a cleaner environment.
基金the Agricultural, Livestock and Fishing De-partment (SAGARPA, No. 12385)the National Forest Commis-sion (CONAFOR, No. 2004-C01-13)the Council of Science and Technology, Mexico
文摘The influence of the physical structure of polyurethane matrix as a support in a solid state culture in tannase production and gallic acid accumulation by Aspergillus niger Aa-20 was evaluated. Three different polyurethane matrices were used as the support: continuous, semi-discontinuous and discontinuous. The highest tannase production at 2479.59 U/L during the first 12 h of culture was obtained using the discontinuous matrix. The gallic acid was accumulated at 7.64 g/L at the discontinuous matrix. The results show that the discontinuous matrix of polyurethane is better for tannase production and gallic acid accumulation in a solid state culture bioprocess than the continuous and semi-discontinuous matrices.
