In order to solve the citrus peel resource waste problem protopectinase-overproducing strain CD-01 for pectin production and minimize the drawbacks of chemical extraction of pectin, a was isolated from a pit soil dump...In order to solve the citrus peel resource waste problem protopectinase-overproducing strain CD-01 for pectin production and minimize the drawbacks of chemical extraction of pectin, a was isolated from a pit soil dumped with perished orange in Changde City, Hunan Province of China. The strain CD-01 had the same morphology and 28S rRNA gene sequence （FJ184995） as that of Aspergillus niger （ATCC 64028）. It was thus identified and named as Aspergillus niger CD-01. The fermentation condition was optimized based on L9（34） orthogonal experimental design and the variances analyses. The results show that the optimal condition for producing pectin is as follows： time 36 h, temperature 35 ℃, pH 5, and urea as the nitrogen source. Under this condition, the pectin yield can reach up to 24.5%. This shows a great potential of Aspergillus niger CD-01 in pectin extraction from citrus.展开更多
Optimal glucose feed strategy for glycerol fed-batch fermentation was investigated by Pontryagin’s maximum principle to maximize the final glycerol yield. The problem was solved by a nonsingular control approach by s...Optimal glucose feed strategy for glycerol fed-batch fermentation was investigated by Pontryagin’s maximum principle to maximize the final glycerol yield. The problem was solved by a nonsingular control approach by selecting the culture volume as the control variable, then the general optimal feed profile was numerically determined.展开更多
为提高海洋来源成团泛菌(Pantoea agglomerans)Y-03产低温甾醇酯酶的酶活力,该研究首先通过单因素试验及Plackett-Burman(PB)试验确定成团泛菌Y-03产低温甾醇酯酶酶活的显著影响因素,然后运用Box-Behnken(BB)响应面试验对其发酵工艺进...为提高海洋来源成团泛菌(Pantoea agglomerans)Y-03产低温甾醇酯酶的酶活力,该研究首先通过单因素试验及Plackett-Burman(PB)试验确定成团泛菌Y-03产低温甾醇酯酶酶活的显著影响因素,然后运用Box-Behnken(BB)响应面试验对其发酵工艺进行优化。结果表明,成团泛菌Y-03产低温甾醇酯酶的最适发酵工艺为葡萄糖添加量3.7%、胰蛋白胨添加量1.3%、K_(2)HPO_(4)添加量0.4%、初始p H值8、转速180 r/min、接种量4%、装液量44 m L/250 m L、发酵温度27℃。在此优化条件下,甾醇酯酶活力为484.24 U/L,相比于优化前酶活力提高143.89%。该研究为提高成团泛菌的甾醇酯酶产量及酶活力和未来放大生产研究奠定了基础。展开更多
基金Projects(50621063, 50674101) supported by the National Natural Science Foundation of China
文摘In order to solve the citrus peel resource waste problem protopectinase-overproducing strain CD-01 for pectin production and minimize the drawbacks of chemical extraction of pectin, a was isolated from a pit soil dumped with perished orange in Changde City, Hunan Province of China. The strain CD-01 had the same morphology and 28S rRNA gene sequence （FJ184995） as that of Aspergillus niger （ATCC 64028）. It was thus identified and named as Aspergillus niger CD-01. The fermentation condition was optimized based on L9（34） orthogonal experimental design and the variances analyses. The results show that the optimal condition for producing pectin is as follows： time 36 h, temperature 35 ℃, pH 5, and urea as the nitrogen source. Under this condition, the pectin yield can reach up to 24.5%. This shows a great potential of Aspergillus niger CD-01 in pectin extraction from citrus.
基金From National Ninth Five Years Project (NO. 96-03-03-03A).
文摘Optimal glucose feed strategy for glycerol fed-batch fermentation was investigated by Pontryagin’s maximum principle to maximize the final glycerol yield. The problem was solved by a nonsingular control approach by selecting the culture volume as the control variable, then the general optimal feed profile was numerically determined.
文摘为提高海洋来源成团泛菌(Pantoea agglomerans)Y-03产低温甾醇酯酶的酶活力,该研究首先通过单因素试验及Plackett-Burman(PB)试验确定成团泛菌Y-03产低温甾醇酯酶酶活的显著影响因素,然后运用Box-Behnken(BB)响应面试验对其发酵工艺进行优化。结果表明,成团泛菌Y-03产低温甾醇酯酶的最适发酵工艺为葡萄糖添加量3.7%、胰蛋白胨添加量1.3%、K_(2)HPO_(4)添加量0.4%、初始p H值8、转速180 r/min、接种量4%、装液量44 m L/250 m L、发酵温度27℃。在此优化条件下,甾醇酯酶活力为484.24 U/L,相比于优化前酶活力提高143.89%。该研究为提高成团泛菌的甾醇酯酶产量及酶活力和未来放大生产研究奠定了基础。
