Lovastatin production by Laetiporus sp. (Bull. ex Fr.) Bond. et Sing. in various solid substrates

I Nyoman Pugeg Aryantha (1,2) Mutiara L. Sidharta (1) and Siti Khodijah Chaerun (1,2)

1) School of Life Sciences and Technology - ITB
2) Center for Life Sciences - ITB
Jalan Ganesha 10 Bandung 40132, INDONESIA
Corresponding author : nyoman@sith.itb.ac.id

ABSTRACT

Several fungi, including Penicillium citrinum, Aspergillus terreus and Pleurotus ostreatus have been reported can produce lovastatin, an anti-cholesterol agent. So far, there is no data on the ability of Laetiporus sp. to produce lovastatin. Our previous finding, indicated that Laetiporus sp. was able to lower cholesterol level in mice blood. This current study was aimed to proof whether Laetiporus sp. can produce lovastatin and what was the effect of different substrates on lovastatin production by using solid state fermentation method. Four different kinds of substrate i.e wood sawdust, coconut fiber, corn cob and black tea waste both ordinary and enriched with cereals. Five day-old mycelial plate culture of Laetiporus sp. was inoculated into eight types of substrate [ordinary wood sawdust (KY-B), enriched wood sawdust (KY-K), ordinary coconut fiber (SK-B), enriched coconut fiber (SK-K), ordinary corn cob (J-B), enriched corn cob (J-K)], ordinary black tea waste (T-B) and enriched black tea waste (T-K) before being incubated over 25 days at room temperature. After incubation period, the culture was harvested and then extracted using methanol : water solution (1:1, pH 7.7). The extracts were then analyzed quantitatively using HPLC. The highest lovastatin concentration (10.41 μg/g) was achieved by ordinary sawdust (KY-B). Based on this result, the production of lovastatin by Laetiporus sp. in KY-B was monitored periodically at time intervals of 8, 16 and 24 days. LOM (Loss of Organic Matter) was also calculated to determine the increase of mycelia biomass during incubation time. The HPLC result showed that the highest lovastatin concentration (37.20 μg/g) was achieved at day 8 of incubation and then decreased significantly on day 16 and 24. The production of lovastatin was adversely related to the increase of mycelial biomass. It is suggested that the degradation of cellulose and hemicellulose from wood sawdust may correspond to lovastatin production by Laetiporus sp.

Keywords: Laetiporus sp., lovastatin, solid state fermentation, sawdust

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Asian Mycological Congress (AMC), Penang Malaysia, 2-6 December 2007