Higher levels of acetaldehyde in beer are one of the major concerns in the current beer industry.Yeast produces acetaldehyde during alcoholic fermentation,and its modification significantly affects beer flavor and qua...Higher levels of acetaldehyde in beer are one of the major concerns in the current beer industry.Yeast produces acetaldehyde during alcoholic fermentation,and its modification significantly affects beer flavor and quality.A different mutant strain with lower acetaldehyde production and improved ethanol tolerance was constructed using the ARTP-ALE mutagenesis strategy with 4-methylpyrazole-disulfiram.As a result of the mutation,the alcohol dehydrogenase activity of the mutant strain decreased to about 71.22%of that of the wild-type strain.At the same time,the fermentation properties and genetic stability of the newly screened strain showed slight differences from the wild-type strain,and there were no safety concerns regarding industrial use of the mutant strain.展开更多
Selenium protects cells from oxidative damage and reduces lipopolysaccharide （LPS）-induced expression of inflammatory cytokines. Because inflammatory cytokines induce growth depression, we hypothesized that selenium...Selenium protects cells from oxidative damage and reduces lipopolysaccharide （LPS）-induced expression of inflammatory cytokines. Because inflammatory cytokines induce growth depression, we hypothesized that selenium-rich yeast （SeY） would inhibit growth depression caused by LPS. Twenty Meishan weanling pigs [28 （s.d. 2 d）, 7.6 （s.d. 0.3 kg） body weight （BW）] were used in a 2×2 factorial design （n=5）. The main factors were dietary Se sources [selenium-rich yeast （SeY） vs. sodium selenite （SSe）] with supplement level at 0.3 mg Se/kg, and immunological stress （LPS vs. saline）. The experiment lasted for 28 d. On d 14 and d 21, half of pigs in each dietary treatment were intramuscularly injected with either 50 μg/kg BW LPS or an equivalent amount of sterile saline. Blood samples were collected at 3 h post-injection. There were no interactions between dietary Se sources and immunological stress on growth performance. LPS depressed average daily gain （ADG） （d 14-21, P〈0.05; d 21-28, P〈 0.01）, and elevated feed to gain ratio （F/G） （d 21-28, P〈0.05）, while SeY elevated ADG （d 0-14, P〈0.05; d 21-28 and d 0-28, P〈0.01）, and decreased F/G （P〈0.01）. Interactions were observed on interleukin-1β（IL-1β） and interleukin-6 （IL-6） from serum samples of d 14 and d 21 （P〈0.01）, as well as superoxide dismutase （SOD） and insulin like growth factor （IGF-1） of d 21 （P〈0.05）. In conclusion, SeY relieved the growth depression of piglets immunologically stressed by LPS, which maybe resulted from the decreased externalization of inflammatory cytokines and improved antioxidant status.展开更多
基金Supported by Heilongjiang Natural Science Foundation Joint Guide Project(LH2019C022)。
文摘Higher levels of acetaldehyde in beer are one of the major concerns in the current beer industry.Yeast produces acetaldehyde during alcoholic fermentation,and its modification significantly affects beer flavor and quality.A different mutant strain with lower acetaldehyde production and improved ethanol tolerance was constructed using the ARTP-ALE mutagenesis strategy with 4-methylpyrazole-disulfiram.As a result of the mutation,the alcohol dehydrogenase activity of the mutant strain decreased to about 71.22%of that of the wild-type strain.At the same time,the fermentation properties and genetic stability of the newly screened strain showed slight differences from the wild-type strain,and there were no safety concerns regarding industrial use of the mutant strain.
文摘Selenium protects cells from oxidative damage and reduces lipopolysaccharide （LPS）-induced expression of inflammatory cytokines. Because inflammatory cytokines induce growth depression, we hypothesized that selenium-rich yeast （SeY） would inhibit growth depression caused by LPS. Twenty Meishan weanling pigs [28 （s.d. 2 d）, 7.6 （s.d. 0.3 kg） body weight （BW）] were used in a 2×2 factorial design （n=5）. The main factors were dietary Se sources [selenium-rich yeast （SeY） vs. sodium selenite （SSe）] with supplement level at 0.3 mg Se/kg, and immunological stress （LPS vs. saline）. The experiment lasted for 28 d. On d 14 and d 21, half of pigs in each dietary treatment were intramuscularly injected with either 50 μg/kg BW LPS or an equivalent amount of sterile saline. Blood samples were collected at 3 h post-injection. There were no interactions between dietary Se sources and immunological stress on growth performance. LPS depressed average daily gain （ADG） （d 14-21, P〈0.05; d 21-28, P〈 0.01）, and elevated feed to gain ratio （F/G） （d 21-28, P〈0.05）, while SeY elevated ADG （d 0-14, P〈0.05; d 21-28 and d 0-28, P〈0.01）, and decreased F/G （P〈0.01）. Interactions were observed on interleukin-1β（IL-1β） and interleukin-6 （IL-6） from serum samples of d 14 and d 21 （P〈0.01）, as well as superoxide dismutase （SOD） and insulin like growth factor （IGF-1） of d 21 （P〈0.05）. In conclusion, SeY relieved the growth depression of piglets immunologically stressed by LPS, which maybe resulted from the decreased externalization of inflammatory cytokines and improved antioxidant status.
