Study On The Carotenoids From A Red Yeast Isolated From The Ovary Of A Wield Puffer Fish

Carotenoids are important natural pigments that are widespread in animals, pl ants and microorganism. Carotenoids have a broad rang functions such as anti-oxidation, anti-ageing, skin protection, reduce rates of cancer and coronary hear t disease, which have been considered as the most potential functional pigment s. The widespread of carotenoids in marine algae, photosynthetic bacteria and y east have been reported, the rich water resource in china supplied rich bio-reso urces for the study of natural products. A red-yeast isolated from a wield puffe r fish was studied in this paper, and the separation and identification of the pi gments from the yeast were carried out. The main works of the paper are liste d as follows:1. First, a strain isolated from a wield puffer fish was identified, which can pr oduce carotenoids. The colony of the strain were big, tangerine, smooth and w et, gram positive, cells were oval, ascospores were observed in staining. DNA of the strain was extracted, and the IST sequences were amplified by PCR. Th e phylogenetic analysis based on the26S rDNA showed that the strain was clo se to Rhodotorula sp. with99%sequence identity. On the base of morphologic al and biochemical characteristics,26S rDNA phylogenetic analysis, the strain was identified as Rhodotorula sp.2. The optimization of culture medium and fermentation conditions were studie d, the result showed that the composition of culture medium have little influen ce both on pigments yield and biomass, but the fermentation conditions (light, temperature, PH) were important for the production of pigments. The optimal c onditions was:sucrose2%, peptone0.6%, yeast extract0.3%, NaCl1%, P H7.2,20℃,160rpm, cultured for84hours without light, the biomass was12.2g/1, and the production of pigments was2.62mg/l。3. The extraction, separation and identification of the pigments from the yeast were researched. The result showed that the treatment of acid and heating were effective for disrupting cells. Open column, specific chemical reactions, thin la yer, UV spectrophotometry, infrared spectrometry, high performance liquid chro matography and NMR analysis were used to separate, identify the pigments. T here were four major fractions separated from the yeast, and two fractions wer e identified as P-carotene and lycopene, respectively.4. The extraction conditions and the stability of the pigments were studied. Det ailed studied showed concentration of the acid, bath time, boil time and resolv ent were major factors, the optimal extract conditions was:the cells were bath ed for1hours in3M HC1, boiling for6min, then extracting with petroleum ether/acetone(2:3) for30min at35℃. The pigments sensitive to light, temperat ure and oxygen, which should be preserved in petroleum ether.