Gametophytes of Laminaria japonica were cryopreserved in liquid nitrogen using encapsulation-dehydration with two-step cooling method. Gametophytes cultured at 10℃ and under continuous irradiance of 30 μmol m-2 s-1 ...Gametophytes of Laminaria japonica were cryopreserved in liquid nitrogen using encapsulation-dehydration with two-step cooling method. Gametophytes cultured at 10℃ and under continuous irradiance of 30 μmol m-2 s-1 for 3 weeks were en- capsulated in calcium alginate beads. The beads were dehydrated in 0.4 molL-1 sucrose prepared with seawater for 6 h, desiccated in an incubator set at 10℃ and 70% relative humidity for 4 h, pre-frozen at either ?40℃ or ?60℃ for 30 min, and stored in liquid nitrogen for >24 h. As high as 43% of survival rate was observed when gametophytes were thawed by placing the beads in 40℃ seawater and re-hydrated in 0.05 molL-1 citrate sodium prepared using 30‰ NaCl 7 d later. More cells of male gametophytes sur- vived the whole procedure in comparison with female gametophytes. The cells of gametophytes surviving the preservation were able to grow asexually and produce morphologically normal sporophytes.展开更多
The dehydration of 2-（4＇-ethylbenzoyl） benzoic acid （BE acid） to 2-ethylanthraquinone （2-EAQ） was investigated over solid acid catalysts. The results showed that H-beta zeolite catalyst modified by dilute HNO3 ...The dehydration of 2-（4＇-ethylbenzoyl） benzoic acid （BE acid） to 2-ethylanthraquinone （2-EAQ） was investigated over solid acid catalysts. The results showed that H-beta zeolite catalyst modified by dilute HNO3 solution exhibited an excellent performance. In our study, the conversion of BE acid can reach 96.7%, and the selectivity to 2-EAQ is up to 99.6%.展开更多
Four groups of antibiotic activity compounds were separated and purified from the ethyl acetate fraction of a broth culture of Streptomyces herbaricolor HNS2-2.Trace analyses were performed and anti-microbial activiti...Four groups of antibiotic activity compounds were separated and purified from the ethyl acetate fraction of a broth culture of Streptomyces herbaricolor HNS2-2.Trace analyses were performed and anti-microbial activities were determined. The antibiotic activity compounds were identified as quercetin dehydrate ①, p-hydroxyphenyl ②, 4’-hydroxyflavanone ③, and 3-hydroxyflavone ④ based on spectroscopic data. Compounds 1-4 showed significant antimicrobial activities against Staphylococcus aureus and the tobacco mosaic virus in vitro, suggesting their potential agricultural and medical applications.展开更多
文摘Gametophytes of Laminaria japonica were cryopreserved in liquid nitrogen using encapsulation-dehydration with two-step cooling method. Gametophytes cultured at 10℃ and under continuous irradiance of 30 μmol m-2 s-1 for 3 weeks were en- capsulated in calcium alginate beads. The beads were dehydrated in 0.4 molL-1 sucrose prepared with seawater for 6 h, desiccated in an incubator set at 10℃ and 70% relative humidity for 4 h, pre-frozen at either ?40℃ or ?60℃ for 30 min, and stored in liquid nitrogen for >24 h. As high as 43% of survival rate was observed when gametophytes were thawed by placing the beads in 40℃ seawater and re-hydrated in 0.05 molL-1 citrate sodium prepared using 30‰ NaCl 7 d later. More cells of male gametophytes sur- vived the whole procedure in comparison with female gametophytes. The cells of gametophytes surviving the preservation were able to grow asexually and produce morphologically normal sporophytes.
文摘The dehydration of 2-（4＇-ethylbenzoyl） benzoic acid （BE acid） to 2-ethylanthraquinone （2-EAQ） was investigated over solid acid catalysts. The results showed that H-beta zeolite catalyst modified by dilute HNO3 solution exhibited an excellent performance. In our study, the conversion of BE acid can reach 96.7%, and the selectivity to 2-EAQ is up to 99.6%.
文摘Four groups of antibiotic activity compounds were separated and purified from the ethyl acetate fraction of a broth culture of Streptomyces herbaricolor HNS2-2.Trace analyses were performed and anti-microbial activities were determined. The antibiotic activity compounds were identified as quercetin dehydrate ①, p-hydroxyphenyl ②, 4’-hydroxyflavanone ③, and 3-hydroxyflavone ④ based on spectroscopic data. Compounds 1-4 showed significant antimicrobial activities against Staphylococcus aureus and the tobacco mosaic virus in vitro, suggesting their potential agricultural and medical applications.
