海南海域海洋红酵母的分离鉴定和应用性能评价

从海南海域的海滩、红树林、渔港码头、产盐滩涂、入海河沟分离海洋红酵母,旨在从中筛选与养殖对象共生的优良菌株。从海南海域分离和纯化海洋红酵母,对海洋红酵母进行形态和生理学及分子生物学的鉴定,大量发酵海洋红酵母,提取分离类胡萝卜素并测定其含量,并将海洋红酵母与鱼虾等养殖对象共培养试验。结果表明,共分离了40多株酵母菌,经形态和生理鉴定以及产类胡萝卜素试验,筛选得到一个高产类胡萝卜素的红酵母属（Rhodotorula）菌株。该菌株在葡萄糖2%、蛋白胨2%、酵母提取物0.3%、核黄素2×10^-6 mol/L、pH 4.5的培养基中,于28℃振荡（180 r/min）培养72 h,其细胞生物产量可达87.55 g/L,类胡萝卜素含量可达520 mg/L;可以在13%高盐和pH 1.0强酸中培养生长;经过与鱼共培养试验,结果显示在合适的菌体浓度条件下,该菌株对鱼无毒害,并与鱼共生。该菌株与鱼共生,显示良好的应用前景,将其应用于盐诱导基因启动子的克隆和盐诱导表达外源基因蛋白（如抗菌肽）的海洋红酵母工程菌的构建,可以更好地应用于水产养殖业。

Isolation and Identification of Rhodotorula in Hainan sea area and Evaluation of Its Application Performance

From the beaches of Hainan sea area, mangroves and fishing wharf, production of salt beaches, rivers into the sea, Rhodotorula were isolated and identified to screen out excellent strains that were symbiotic with aquaculture object. Rhodotorula benthica were isolated and purified from Hainan sea area; the identifications of morphological, physiological and molecular biology were conducted; Rhodotorula benthica were fermented largely, then carotenoids were isolated and its production was mensurated; Co-culture experiments were tested between Rhodotorula benthica and fish. The result showed that more than 40 isolated strains of yeast were obtained using the medium for isolation of Rhodotorula. A high-yield carotenoid which was Rhodotorula strains was screened out through identification of morphological and physiological tests as well as the production of carotenoids. After the strain was cultured for 72 hours in 2% glucose, 2% peptone, 0.3% yeast extract, riboflavin 2×10^-6 mol/L, pH 4.5 medium at 28℃ oscillation （180 r/min）, the cell biological production of the strain is up to 87.55 g/L, carotenoid production is up to 520 mg/L. It can grow at 13% in high-salt and superacid pH 1.0 medium. With the fish co-culture experiments, the results showed that in the right cell concentration conditions, the strain is non-toxic and symbiotic with fish. The strain is symbiotic with fish, indicating a good prospect. It is currently applied to salt-induced gene promoter cloning and salt-induced gene expression of exogenous proteins （such as antimicrobial peptides） of the marine Rhodotorula construction.