Isolation, identification and odour-producing abilities of geosmin/2-MIB in actinomycetes from sediments in Lake Lotus, China

Abstract

This study aimed to determine whether actinomycetes could contribute to the odours occurring in Lake Lotus, China. In total, 55 actinomycete strains were isolated from sediments in Lake Lotus and their odorous metabolites, geosmin and 2-methylisoborneol (2-MIB), were identified using HSPME-GC-MS. Results showed that 24, 23 and 34 strains produced geosmin and/or 2-MIB in Gause, TSB and M liquid media, respectively. Of odour-producing actinomycetes, most could produce geosmin and some produced both metabolites, while few of them produced only 2-MIB. Six isolates with high-level odour were selected for further investigation. Their biomass and odour-producing abilities were monitored in both the slants and liquid media. The results suggest that TSB was the most suitable medium for the growth of mycelium; Gause and M slant supported good production of spores, while M liquid medium was the most favourable for the production of both geosmin and 2-MIB. Those strains that produced geosmin only were less influenced than those that produced both geosmin and 2-MIB under shaking conditions.The results indicate that actinomycetes from sediments should be taken into consideration when off-flavours occur in water columns. According to the 16S rRNA sequences, six actinomycetes were classified in the Streptomyces.

Contribution of Streptomyces in sediment to earthy odor in the overlying water in Xionghe Reservoir, China

“…isolated from the sediments of Lake Lotus (Zuo et al, 2009). Furthermore, the amount of geosmin produced by S. massasporeus was only 0.18 ng mg À1 dw À1 , which was even lower than the 4.5 ng mg À1 dw À1 produced by Streptomyces malaysiensis (Tung et al, 2006).…”

Study of Geosmin and 2-Methylisoborneol (MIB) Producers in Phayao Lake, Thailand

“…could have significantly contributed to the prevalence of geosmin over MIB in both water and sediments of Phayao Lake. Zuo et al [18] observed Streptomyces was the main species responsible for the earthy-musty odour and produce geosmin more than MIB in Lake Lotus, China. Non-odor producer 5…”

Harmful Algal Blooms

“…Extra-and intracellular production varies among species, different growth phases, and (in some species) the formation of akinetes and heterocytes and in response to environmental factors such as light, temperature, and nutrients (Wu et al, 1991;Komatsu et al, 2008;Zuo et al, 2009). Extra-and intracellular production varies among species, different growth phases, and (in some species) the formation of akinetes and heterocytes and in response to environmental factors such as light, temperature, and nutrients (Wu et al, 1991;Komatsu et al, 2008;Zuo et al, 2009).…”