Preliminary Study On Bacterial Diversity In Yunnan Non-ferrous Metals Mining

With the depletion of mineral resources, the exploitation of low-grade ore and tailings is very important in mineral industry. Microorganisms have a good prospect of application in metallurgy, for they can be used to process low-grade ore and tailings and play a role in environmental protection. Yunnan province is famous as a kingdom of non-ferrous metals in china. However, so far, systematical study on the bacterial diversity has not been reported yet. It is necessary to start such similar studies, in order to make the best use of microbes in mineral industry in Yunan.Solid broth medium, egg yolk medium and PYGV medium were used to isolate and identify cultivable bacterial species from the samples collected from three typical mines in Yunnan province.1930 bacterial strains were isolated from the samples of Beiya gold deposit, which were then classified into about 55 species by their colony morphology.16 strains with distinct morphology were further characterized. Results revealed that they belonged to 9 genera:Bacillus, Staphylococcu, Streptomyces, Janibacte, Arthrobacte, Kocuria, Plantibacte, Nocardia and Microbacterium, respectively. Moreover,3/4 of the total isolates were assigned to Actinomycetes, while the others were strains of genus Bacillus and Staphylococc, and strains of genus Plantibacte and Microbacterium were dominant.Similarly,541 strains belonged to 46 species were isolated from the samples of Lanping lead-zinc Deposit.15 strains with distinct morphology were also further characterized. Results showed that they belonged to 9 genera:Bacillus Paenibacillu, Sporosarcina, Arthrobacter, Skermanella, Kocuria, Micrococcus, Pseudomonas and Brevundimonas. More than half of the isolates were Actinomycetes, and the strains of genus Micrococcu and Arthrobact were dominant.520 strains belonged to 46 species were isolated from the samples of Funing magnetite deposit, and 13 isolates distinct morphology morphology were also further characterized. The results revealed that these 13 strains belonged to 4 genera Bacillus, Staphylococc, Arthrobacter and Pseudomonas of Actinobacteria, Firmicutes and Proteobacteria. Bacillus srains were dominant and accounted for% of the total isolates in this area. The other two less dominant genera were Arthrobact and Pseudomonas that accounted for about 5% and 8%, respectively.Besides, isolation and identification of microbial diversity in the ore samples of Beiya gold deposit were carried out. The results showed that 6 species belonged to 4 genera Bacillus, Kocuria, Arthrobacterand and Paenibacillus were obtained. Species belonged to genus Bacillus, Kocuria and Arthrobacterand were also isolated from the samples of external environment of Beiya gold deposit, while Paenibacillus was specifically detected in the ore samples. Meanwhile, the results also indicated that Bacillus cereus, as an indicative species in gold deposits, was not detected in the samples from Beiya gold deposit, which was verified by using culture dependent and culture independent methods and FISH technique.In conclusion, species mainly belonged to Actinobacteria, Firmicutes and Proteobacteria were isolated in the samples from three typical mines in Yunan province, and the diversities and compositions of bacterial populations in these three mines were different with each other. Bacterial compositions in the ore samples were different from that in the samples from external environment of the Beiya gold deposit. Moreover, Bacillus cereus was not detected in samples from Beiya gold deposit, indicating that application of this strain as an indicative species of gold deposit need to be verified.