Abstract
A lipid producing yeast was screened from leaves of Albabiscus and was identified as a Rhodotorula graminis SW 214. During the shakining incubation of 8 days at $25^{\circ}C$, the yeast produced extracellular lipids of 7.3g/l of the media. The relative concentration of carbon and nitrogen sources in the media influenced the extracellular lipid production greatly. When with nitrogen sources in the media were almost exhausted for growth of the yeast the sufficient carbon sources, the lipid production proceeded vigorously. Eight days of batch cultivation with 8% glucose, 2.5g/l of yeast extract, $KH_{2}PO_{4}(1g/l)\;MgSO_{4}\;(0.2g/l)$ and pH 6 gave maximum biomass and extracellular lipid production of 8.05g/l and 8.89g/l, respectively. The acid value, saponificatio value, the iodine value, ad the unsaponifiable matter of the extracellular lipids of Rhodotorula graminis SW 214 were 2.6, 534, 5.1 and 2.4, respectively. Lipid was constituted 75.2% triglyceride, 5.9% free fatty acid, 10.8% phospholipid, 4.9% esterified sterol and 3.3% free sterol. Major fatty acids found were 3-hydroxypentadecanoate, 3-hydroxyhexadecanate, trans-9-octadecanate, cis-9-hexadecanate (hydroxy palmitic), 15-methylhexadecanate (oleic), 18-methylno-nadecanate, octadecanate (stearic) and 3-hydroxytridecante.
알바비스커스 잎으로부터 세포외 지질을 대량 생산하는 효모를 분리하고 동정한 결과 Rhodotorula graminis SW 214로 확인하였으며, $25^{\circ}C$에서 8일간 진탕배양시 Rhodotorula graminis SW 214 세포의 지질 생산량은 7.31g/l였다. 배지내의 질소원과 탄소원의 농도는 세포의 지질 생산에 큰 영향을 주었는데 배지내의 질소원이 효모 성장에 거의 이용되고 탄소원이 아직 남아 있을때 지질 생산이 활발히 이루어졌다. 배지내에 질소원 농도가 높은 동안에는 지질 생산이 더디게 이루어졌다. Rhodotorula graminis SW 214 세포의 지질 생산량의 최적조건으로는 gluaminis SW 214 세포의 지질 생산량의 최적조건으로는 glucose 8%, yeast extract 2.5g/l, $KH_{2}PO_{4}\;1g/l,\;MgSO_{4}{\cdot}7H_{2}O\;0.2g/l$, pH6에서 8일간 배양할 때임을 알 수 있었고 효모건조 균체량은 8.05g/l, 지방 생산량은 8.89g/l였다. Rhodotorula graminis SW 214 세포의 지질의 TLC에 의한 분별 정량 결과는 triglyceride 75.16%, phospholipid 10.77%, free fatty acid 5.88, esterified sterol 4.94%, free sterol 3.25%였다. Rhodotorula graminis SW 214 세포의 지방의 주된 지방산 조성은 3-hydroxypentadecanate 37.90%, 3-hydroxypentadecanate 20.80%, trans-9-octadecanate 11.53%, cis-9-headecanate 10.93%, 15-methylhexadecanate 9.82%, 18-methylnonadecanate 4.63%, octadecanate 2.64%, 3-hydroxytridecanate 1.75%였다.