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The purpose of this study is to improve the environmental pollution problem, the strains which can produce glycolipid biosurfactant and degrade petroleum hydrocarbons efficiently were screened out in this study. Six strains of glycolipid-producing fungi were isolated from the surface of apple skin by the methods of blood plate and oil plate. After comparing the oil drainage ability of each strain and using PCR to amplify the key genes for the synthesis of glycolipid surfactants, we screened a fungus K6 with emtl sequence. The strain was identified by morphological, physiological and biochemical tests and molecular phylogenetic analysis (5.8S, ITS1, ITS2). Its metabolites were analyzed by TLC and HPLC. The strain was identified as Pseudozyma churashimaensis, which could produce mannose and erythritol. The experiment of petroleum hydrocarbon degradation shows that strain K6 has strong emulsifying ability and the ability of degrading petroleum hydrocarbon. Strain K6, with the strong ability in producing biosurfactants and degrading petroleum, will have broad application prospects for bioremediation of petroleum contaminated environment.

The presence of cancer stem cells (CSCs) is a major cause of therapeutic failure in a variety of cancer types, including colorectal cancer (CRC). However, the underlying mechanisms that regulate the self‑renewal of colorectal cancer stem cells (CRCSCs) remain unclear. Our previous study utilized CRCSCs and their parent cells; through gene microarray screening and bioinformatics analysis, we hypothesized that microRNA (miR)‑8063 may bind to, and regulate the expression of, heterogeneous nuclear ribonucleoprotein AB (hnRNPAB) to facilitate the regulation of CRCSC self‑renewal. The aim of the present study was to confirm this conjecture through relevant experiments. The results indicated that compared with that in parent cells, miR‑8063 expression was significantly downregulated in CRCSCs, while hnRNPAB expression was increased. Furthermore, hnRNPAB was identified as a direct target of miR‑8063 using a dual‑Luciferase assay. Overexpression of hnRNPAB promoted the acquisition of CSC characteristics in CRC cells (increased colony formation ability, enhanced tumorigenicity, and upregulated expression of CSC markers), as well as the upregulation of key proteins (Wnt3a, Wnt5a and β‑catenin) in the Wnt/β‑catenin signaling pathway. Similarly, after silencing miR‑8063 in CRC cells, the characteristics of CSC were altered, and the expression of hnRNPAB protein was promoted. However, post overexpression of miR‑8063 in CRCSCs, the self‑renewal ability of CSCs was weakened with the downregulation of hnRNPAB protein, Wnt3a, Wnt5a and β‑catenin. These results suggest that as a tumor suppressor, miR‑8063 is involved in regulating the self‑renewal of CRCSCs, where loss of miR‑8063 expression weakens its inhibition on hnRNPAB, which leads to the activation of Wnt/β‑catenin signaling to promote the self‑renewal of CRCSCs.