出芽短梗霉F4的溶磷能力及机理

Phosphate solubilization of Aureobasidium pullulan F4 and its mechanism

从安徽省铜陵市铜官山尾矿库木贼根际分离筛选出的出芽短梗霉F4,以磷酸钙、磷酸铝、磷酸铁和磷矿粉4种不同磷源进行液体培养,测定培养液的pH、水溶性磷、菌体磷及有机酸含量.结果表明:菌株F4对不同磷源的溶磷能力为:磷酸铝>磷酸铁、磷酸钙>磷矿粉,溶磷量均高于200 mg·L-1;培养液pH在48 h内迅速下降,以磷酸铝、磷酸铁为磷源的培养液pH下降幅度明显大于磷酸钙与磷矿粉.出芽短梗霉F4产生的有机酸主要为草酸、柠檬酸和酒石酸,其中,以草酸为主.菌株的溶磷能力与有机酸无显著相关性,而与pH呈显著相关.接种出芽短梗霉F4时加入葡萄糖,尾矿中速效磷含量显著增加,说明出芽短梗霉F4在尾矿生态修复中具有潜在的应用价值.

The Aureobasidium pullulans F4 was isolated from the rhizosphere simum in Tongguanshan mine wasteland in Tongling City, Anhui Province of Hippochaete ramosis- Liquid culture was conducted with four kinds of phosphorus sources, calcium phosphate, aluminum phosphate, ferric phosphate and rock phosphate to determine the pH, dissolved phosphorus, phosphorus in the bacte- ria and organic acid in the solution. The results showed that the phosphate solubilization by A. pul- lulans F4 varied with phosphorus sources, which decreased in order of aluminum phosphate 〉 ferric phosphate, calcium phosphate 〉 rock phosphate. The amounts of dissolved phosphorus in the differ- ent treatments were all higher than 200 mg ~ L-1. The pH of the medium dropped immediately in 48 h, and the aluminum phosphate and ferric phosphate treatments showed a greater decrease in pH than the calcium phosphate and rock phosphate treatments. The organic acid synthesized by A. pul- lulans F4 included oxalic acid, citric acid and tartaric acid, and oxalic acid, among which oxalic acid was the dominated component. The phosphate dissolving capacity of A. puUulans F4 showed no significant correlation with organic acid, but significantly correlated with the pH. The available phosphorus was significantly improved with the combined application of A. pullulans F4 and glucose, suggesting A. pullulans F4 was a potent candidate for remediation of copper mine wastelands.