Studies On Species Diversity Of Lachnum And Its Pigment

Species diversity of Lachnum from Huangshan Moutains Anhui China weresurveyed, Nine taxa were reported.Tissue isolation was performed on 97 discomycetes specimens fromHuangshan Mountains, 33 filament products were obtained. Culture conditions of L.brasiliense84-2, L. sclerotii88-2, L. singerianum95-1 were studied. The resultsshowed that the optimum conditions for the growth were potato 250 g/L, glucose 20g/L, VB₁ 0.01 g/L, 25℃, pH 5.5. The optimum conditions for producingmelanin of L. brasiliense84-2 were as follows: potato 250 g/L, glucose 5 g/L,KNO₃ 5 g/L, L-tyrosin 1 g/L, 25℃, pH 7.0.Preliminary studies on the property of melanin produced by L. brasiliense84-2were carried out, the results showed that the melanin is soluble in NaOH solutionand dimethylsulfoxide, slight soluble in water, but failed in methanol, ethyl acetate,HCl solution, anhydrous ethanol, chloroform, acetone, acetonitrile; The melanin isstable to temperature, not sensitive to ultraviolet light, sunlight, Sodium benzoate,Citric Acid and sucrose, has no effect when treated with K⁺, Na⁺, Ca(²+), Al³⁺,Cu²⁺ and reducing agents. However, the melanin is not stable to Mg²⁺, Fe³⁺, Mn²⁺and oxidant.The structure of melanin was studied. The result showed that the melanin is akind of sheet crystalloid whose surface is anomalistic, and it has functional groupsof aryl, -OH, -NH, -COOH, thiazinyl etc. It was concluded that melanin has thestructure model of both Eumelanin and Pheomelanin.