Antifungal Activity and Cultural Characteristics of the Streptomyces sp. A252

Streptomyces sp. A252의 배양적 특성 및 항진균활성

The growth rate of the A252 strain was increased in tryptic soy broth (TSB) and malt extract-yeast extract medium (ISP-2), but the antifungal activity of culture filtrate was efficient in the media of TSB and nutrient broth. The mycelial growth and the antifungal activity of culture filtrate in TSB medium were optimized at $25^{\circ}C$ and pH 6.5. The growth in 2$\%$TSB concentration was more effective than 1$\%$, but there was no difference of the antifungal activity by the TSB concentrations. The mycelial growth of A252 strain reached to maximum at 72 hr after inoculation, whereas the antifungal activity of culture filtrate was shown to have the highest level at idiophase (60 hr) after inoculation and was decreased a little after 96 hr incubation. The antifungal activity was stable in the pH range of 4 to 11 and evenly at $121^{\circ}C$. The A252 strain was characterized as Streptomyces species by the physiological properties and examination of sporophore me morphology.

A252 균주의 항균성물질의 생성 및 균주의 배양적 특성을 조사한 결과 균체의 생장은 TSB와 malt extract-yeast extract (ISP-2) 배양기가 좋았으며, 배양여액의 항균활성은 TSB와 nutrient broth에서 효과적이였다. TSB 배지에서 균사생장 및 배양여액의 항균활성은 $25^{\circ}C$와 pH 6.5에서 최적화 되었으며, 2$\%$ TSB 농도에서는 1$\%$에 비해 생장은 좋았으나 배양여액의 항균활성에는 차이가 없었다. A252 균주의 균사 생장은 접종 72시간 후에 최대치에 달하였으며 반면 배양액의 항균력은 접종 60시간 후인 idiophase에 가장 높은 수준을 보였지만 96시간 후에는 약간 감소하는 경향을 나타냈다. 배양여액의 항균활성은 $121^{\circ}C$ 고온에서도 안정하였으며, pH에 대한 안정성은 4.0 - 9.0의 범위였다. A252 균주의 생리적 특성 및 분생자경의 형태 등을 관찰한 결과 Streptomyces sp.로 동정되었다.