영지(Ganoderma lucidum) 균사체의 액체배양에 의한 세포외 생물고분자의 생산조건과 특성 = Production Conditions and Characterization of the Exo-biopolymer Produced by Submerged Cultivation of Ganoderma lucidum Mycelium

국문 초록 (Abstract)

새로운 생물산업소재의 탐색 및 개발연구의 일환으로 Ganoderma lucidum(영지1호) 균사체의 액체배양에 의하여 세포외 생물고분자의 생산을 위한 최적 생산조건을 검토하였고, 생성 생물고분자를 분획 정제하여 이의 성분특성을 조사하였다.
세포의 생물고분자 생산을 위한 최적 배양조건은 glucose 5%, yeast extract 0.5%, (NH_4)_2HPO_4 0.1% 및 KH_2PO_4 0.05%(w/v)를 함유한 배지에서 pH 5.0, 온도 30℃ 및 교반속도 100 rpm일 때 얻어졌다. 이들 조건하에서 7일간 플라스크 배양하였을 때, 최대의 균체 및 세포외 생물고분자 농도는 각각 15.2 및 18.8 g/l이었으며, 비생육속도, 비기질소비속도 및 비생산속도는 각각 0.039 hr^-1, 0.043 gg ^-1hr^-1이었다. 세포의 생물고분자는 실온의 물추출에 의하여 수용성 및 물불용성 다당류로 분획되었으며, 두 시료 모두 97% 이상의 당을 함유하였다. 수용성 생물고분자 분획(BWS)과 물불용성 분획(BWI)은 모두 glucose, galactose, mannose, xylose 및 fucose를 함유하였으며, 구성당의 몰비는 각각 3.6 : 1.5 : 2.1 : 0.5: trace 및 2.9 : 3.1 : 2.0 : 1.6 : 0.3이었다.

다국어 초록 (Multilingual Abstract)

For the screening and the development of the new bio-material, cultural conditions for the exo-biopolymer (EBP) production through the submerged cultivation of Ganoderma lucidum mycelium were investigated. Also, the fractionations and the purifications of the exo-biopolymer were carried out and the chemical compositions of the exo-biopolymer were examined. The optimal culture conditions for the exo-biopolymer production were pH 5.0, 30℃ and 100 rpm of agitation speed in the medium containing of 5% (w/v) glucose, 0.5% (w/v) yeast extract, 0.1% (w/v) (NH_4_)_2HPO_4, and 0.05% (w/v) KH_2PO_4. In the flask cultivation for 7 days under these conditions, the concentration of the maximum exo-biopolymer and the cell mass were 15.4 g/l and 18.8 g/l, respectively. The specific growth rate was 0.039 hr^-1. In addition, the substrate consumption rate, and the exo-biopolymer production rate were 0.043 gg ^-1hr^-1 and 0.025 gg ^-1hr^-1, respectively. The exo-biopolymer was fractionated into BWS (water soluble exo-biopolymer) and BWI (war insoluble exo-biopolymer) by the water insoluble exo-biopolymer) by the water extraction, and the sugar contents fo two fractions were higher than 97% (based on dry basis). The components sugar of BWS and BWI fractions were glucose, galactose, mannose, xylose, and fucose. Their molar ratios were 3.6:1.5:2.1:0.5: trace and 2.9:3.1:2.0:1.6:0.3, respectively.