Chemoheterotrophic Sulfur Oxidising Microorganisms of a Terai Soil I. Oxidation of Inorganic and Organic Sulfur by Microorganisms, Isolated in Sucrose-Sodiumthiosulfate Agar

Among twenty one chemoheterotrophic sulfur-oxidising microorganisms, isolated in sucrose-sodium-thiosulfate agar plates from a representative Indian Terai Soil — a Himalayan foot hill soil of the Order Mollisol (Typic Haplaquept). Thirteen isolates were bacteria, twelve belong to the genus Bacillus, and one to Micrococcus, three actinomycetes to the genus Streptomyces. Five isolates were fungi — two of the genus Penicillium, and three of the genus Aspergillus. Of these, the efficient sulfur oxidisers were Bacillus spp — TSB₅ and TSB₆, Streptomyces sp. — TSA₁, and Aspergillus spp. — TSF₃ and TSF₅. In general, the oxidation by the isolates was essentially higher from the inorganic sulfur source, sodiumthiosulfate than from the organic sulfur source, L-cystine. The overall efficiency of the genera decreases in following order Aspergillus, Penicillium, Streptomyces, Bacillus and Micrococcus.

Aus repräsentativen indischen Terai-Böden (am Fuß des Himalaja-Gebirges), die Inceptisol-Haplaquept-Bodentypen entsprechen, wurden auf Saccharose-Natriumthiosulfat-Agarplatten 21 chemoheterotrophe Schwefel-oxidierende Mikroorganismen isoliert. 16 Mikrobenisolate waren Bakterien, 12 davon gehörten zur Gattung Bacillus, einer zur Gattung Micrococcus, 3 zur Gattung Streptomyces. 5 Isolate waren Pilze, 2 Penicillium- und 3 Aspergillus-Anten. Von diesen waren die effizientesten Schwefeloxidanten 2 Bacillusspezies: TSB₅ und TSB₆, ein Streptomycesholat TSA₁ sowie die beiden Aspergillusisolate TSF₃ und TSF₅. Allgemein war die Schwefeloxidation auf den anorganischen S-Quellen (Na-thiosulfat) wesentlich höher als auf der organischen S-Quelle 1-Cystin. Die Schwefeloxidation nahm ab in der Reihenfolge: Aspergillus, Penicillium, Streptomyces, Bacillus, Mucrococcus.