In this paper, studies were carried out to extract astaxanthin from discharged wastewater during the production of chitin and to reveal the scavenging effect of the obtained pigment on 1, 1-diphenyl-2-picrylhydrazyl (...In this paper, studies were carried out to extract astaxanthin from discharged wastewater during the production of chitin and to reveal the scavenging effect of the obtained pigment on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. Different ratios of dichloromethane/methanol (V/V) were used to extract astaxanthin. When the ratio of dichloromethane/methanol was 2:8 and the ratio between the mixed organic solvent (dichloromethane/methanol, 2:8, V/V) and wastewater was 1:1, the highest yield of pigment was obtained (8.4 mg/ 50 mL). The concentration of free astaxanthin in the obtained pigment analyzed by HPLC was 30.02%. The obtained pigment possessed strong scavenging ability on DPPH radical and IC50 was 0.84mg/ml.展开更多
In general,productions of natural pigment in submerged microorganism culture were much less than that in solid-state fermentation,because the solid-state culture can provide a support carrier for the mycelium. To impr...In general,productions of natural pigment in submerged microorganism culture were much less than that in solid-state fermentation,because the solid-state culture can provide a support carrier for the mycelium. To improve natural pigment production,the cultivation of Monascus purpureus in submerged encapsulated cell was investigated. Monascus purpureus immobilized in polyelectrolyte complex(PEC) microcapsules,which were pre-pared by sodium cellulose sulphate(NaCS) and poly-dimethyl-diallyl-ammonium chloride(PDMDAAC),was a good substitute for submerged cell culture because it mimicked the solid-state environment. The repeated-batch process with encapsulated cells was studied in flasks and a bubble column. The results indicated that the bubble column was more suitable for the encapsulation culture than the shaking flasks because of its good mass transfer performance and minor shear stress on cells. Owing to the protection of the microcapsule's membrane,Monascus purpureus in microcapsules increased approximately three times over that in free cell culture with negligible cell leakage to the medium. The pigment production in the bubble column finally reached 3.82(OD500) ,which was two times higher than in free cell culture. In addition,the duration of each batch was shortened to 15% of that in free cell culture.展开更多
Because conditions for the grain production are not favorable and the input in the production factors ofmodern agriculture is not sufficient, the grain supply has been less than the demand for a long time. By means of...Because conditions for the grain production are not favorable and the input in the production factors ofmodern agriculture is not sufficient, the grain supply has been less than the demand for a long time. By means of greycorrelation analysis, this paper deals with the correlation situation among such input factors as the grain sown area, thetotal power of agricultural machinery, the fertilizer utilization volume, the actual irrigation area, the damage area, thenumber of farming labor force, in order to understand the major restricting and driving forces that have affected thegrain output in the recent 23 years. The analysis shows that the grain sown area and fertilizer utilization volume are thetwo most important leading factors that affect grain production in Guizhou Province, while the damage area and the totalpower of the farming-used machines are the following factors. Fertilizer utilization volume and the actual agriculturalmachinery and irrigation area are the two increasingly influential factors that affect grain production. The influence of thefarming labor force upon grain production became less strong. The main measures to increase grain production outputin Guizhou Province are to stabilize the arable land, increase the actual irrigation area, expedite the transfer of thefarming labor force and increase the input of modern agriculture.展开更多
Mierocystis aeruginosa FACHB 905 was used as a model organism to study the ellects oI small water clusters （SWCs） on the growth and microcystin （MC） production of toxic cyanobacteria. The results showed that SWCs ...Mierocystis aeruginosa FACHB 905 was used as a model organism to study the ellects oI small water clusters （SWCs） on the growth and microcystin （MC） production of toxic cyanobacteria. The results showed that SWCs were able to stimulate the growth of Microcystis aeruginosa, which resulted in increased cell numbers and higher specific growth rates after a 30-d treatment. The cell morphology indicated that Microcystis aeruginosa was in a better state of growth, and it was more prone to divide in SWCs than in normal water clusters. The SWCs treatment up-regulated MC synthesis and exudation in 10 d in Microcystis aeruginosa, and the intra-cellular MC content de- creased after the 20th day subsequently. Moreover, the cellular photosynthetic pigment contents were temporarily stimulated by SWCs. A possible reason is that SWCs stimulated the growth by promoting photosynthesis, whereas the increased MC production was relevant to pigment contents.展开更多
基金financially supported by the Science and Technology Administration of Shandong Province, China (20042504)
文摘In this paper, studies were carried out to extract astaxanthin from discharged wastewater during the production of chitin and to reveal the scavenging effect of the obtained pigment on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. Different ratios of dichloromethane/methanol (V/V) were used to extract astaxanthin. When the ratio of dichloromethane/methanol was 2:8 and the ratio between the mixed organic solvent (dichloromethane/methanol, 2:8, V/V) and wastewater was 1:1, the highest yield of pigment was obtained (8.4 mg/ 50 mL). The concentration of free astaxanthin in the obtained pigment analyzed by HPLC was 30.02%. The obtained pigment possessed strong scavenging ability on DPPH radical and IC50 was 0.84mg/ml.
基金Supported by the National Basic Research Program of China（2007CB707805） the National Natural Science Foundation of China（20876139）
文摘In general,productions of natural pigment in submerged microorganism culture were much less than that in solid-state fermentation,because the solid-state culture can provide a support carrier for the mycelium. To improve natural pigment production,the cultivation of Monascus purpureus in submerged encapsulated cell was investigated. Monascus purpureus immobilized in polyelectrolyte complex(PEC) microcapsules,which were pre-pared by sodium cellulose sulphate(NaCS) and poly-dimethyl-diallyl-ammonium chloride(PDMDAAC),was a good substitute for submerged cell culture because it mimicked the solid-state environment. The repeated-batch process with encapsulated cells was studied in flasks and a bubble column. The results indicated that the bubble column was more suitable for the encapsulation culture than the shaking flasks because of its good mass transfer performance and minor shear stress on cells. Owing to the protection of the microcapsule's membrane,Monascus purpureus in microcapsules increased approximately three times over that in free cell culture with negligible cell leakage to the medium. The pigment production in the bubble column finally reached 3.82(OD500) ,which was two times higher than in free cell culture. In addition,the duration of each batch was shortened to 15% of that in free cell culture.
文摘Because conditions for the grain production are not favorable and the input in the production factors ofmodern agriculture is not sufficient, the grain supply has been less than the demand for a long time. By means of greycorrelation analysis, this paper deals with the correlation situation among such input factors as the grain sown area, thetotal power of agricultural machinery, the fertilizer utilization volume, the actual irrigation area, the damage area, thenumber of farming labor force, in order to understand the major restricting and driving forces that have affected thegrain output in the recent 23 years. The analysis shows that the grain sown area and fertilizer utilization volume are thetwo most important leading factors that affect grain production in Guizhou Province, while the damage area and the totalpower of the farming-used machines are the following factors. Fertilizer utilization volume and the actual agriculturalmachinery and irrigation area are the two increasingly influential factors that affect grain production. The influence of thefarming labor force upon grain production became less strong. The main measures to increase grain production outputin Guizhou Province are to stabilize the arable land, increase the actual irrigation area, expedite the transfer of thefarming labor force and increase the input of modern agriculture.
基金Supported by National High Technology Research and Development Program of China ("863" Program,No.2012AA063504)National Natural Science Foundation of China(No.20676094)Scientific Project of Ocean Development of Tianjin Oceanic Administration(No.KJXH2011-10)
文摘Mierocystis aeruginosa FACHB 905 was used as a model organism to study the ellects oI small water clusters （SWCs） on the growth and microcystin （MC） production of toxic cyanobacteria. The results showed that SWCs were able to stimulate the growth of Microcystis aeruginosa, which resulted in increased cell numbers and higher specific growth rates after a 30-d treatment. The cell morphology indicated that Microcystis aeruginosa was in a better state of growth, and it was more prone to divide in SWCs than in normal water clusters. The SWCs treatment up-regulated MC synthesis and exudation in 10 d in Microcystis aeruginosa, and the intra-cellular MC content de- creased after the 20th day subsequently. Moreover, the cellular photosynthetic pigment contents were temporarily stimulated by SWCs. A possible reason is that SWCs stimulated the growth by promoting photosynthesis, whereas the increased MC production was relevant to pigment contents.
