A metabolic mechanism for oxalic acid biosynthesis in the woodrotting basidiomycete Fomitopsis palustris has been proposed on the basis of biochemical analyses of glucose metabolism. There was a strong correlation between glucose consumption and oxalate production. Oxalic acid was found to accumulate in the culture fluid in about 80% of the theoretical yield or about 5-fold, on the basis of the fungal biomass harvested. The results clearly indicate that glucose was not completely oxidized to CO2 by the tricarboxylic acid (TCA) cycle but converted mainly to oxalate. The determination of the 12 enzymes concerned has revealed the occurrence of the unprecedented metabolic coupling of the TCA and glyoxylate cycles that support oxalate biosynthesis. In this metabolic system, isocitrate lyase (EC 4.1.3.1), together with oxaloacetase (EC 3.7.1.1), was found to play a pivotal role in yielding oxalate from oxaloacetate via the acetate-recycling routes. Moreover, malate dehydrogenase (EC 1.1.1.37), with an extraordinarily high activity among the enzymes tested, was shown to play an important role in generating NADH by oxidation of malate to oxaloacetate. Thus, it is proposed that the wood-rotting basidiomycete acquires biochemical energy by oxidizing glucose to oxalate.

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A study on the isolation and characterization of chitinolytic bacteria and their potential to inhibit plant pathogenic fungi has been done. The bacteria were isolated from the soil of Karo, Langkat, and Bangka, Sumatra. Ganoderma boninense, Fusarium oxysporum, and Penicillium citrinum of the stock cultures in Laboratory of Microbiology Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara were used for growth inhibition assay by the isolated bacteria. KR05 and LK08 shared similar morphological and physiological characters; like wise, KR07 shared property similarities with BK08. All bacterial isolates inhibited the growth of G. boninense F. oxysporum , and P. citrinum at a different extent. LK08 showed the highest inhibition rate followed by BK07 and BK09. However, P. citrinum was inhibited more by BK07 and BK09. The crude enzyme preparation of the latter isolate exhibited the highest chitinase activity. The result suggested that their swarming activity seemed to contributed to inhibition of fungal growth