Petroleum, as the major energy source, is indispensable from our lives. Presence of compounds resistant to degradation can pose risks for human health and environment. Basidiomycetes have been considered as powerful candidates in biodegradation of petroleum compounds via secreting ligninolytic enzymes. In this study a wood-decaying fungus was isolated by significant degradation ability that was identified as Daedaleopsis sp. by morphological and molecular identification methods. According to GC/MS studies, incubation of heavy crude oil with Daedaleopsis sp. resulted in increased amounts of C24 compounds. Degradation of asphaltene, anthracene, and dibenzofuran by the identified fungal strain was determined to evaluate its potential in biodegradation. After 14 days of incubation, Daedaleopsis sp. could degrade 93.7% and 91.2% of anthracene and dibenzofuran, respectively, in pH 5 and 40 °C in optimized medium, as revealed by GC/FID. Notably, analysis of saturates, aromatics, resins, and asphaltenes showed a reduction of 88.7% and 38% in asphaletene and aromatic fractions. Laccase, lignin peroxidase, and manganese peroxidase activities were enhanced from 51.3, 145.2, 214.5 U ml in the absence to 121.5, 231.4, and 352.5 U ml in the presence of heavy crude oil, respectively. This is the first report that Daedaleopsis sp. can degrade asphaltene and dibenzofuran. Moreover, compared to the reported results of asphaltene biodegradation, this strain was the most successful. Thus, Daedaleopsis sp. could be a promising candidate for biotransformation of heavy crude oil and biodegradation of recalcitrant toxic compounds.

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The genes encoding Cys2/His2-type zinc finger proteins constitute a large family in higher plants consisting of a family of plant transcription factors. GpZF encodes a Cys2/His2-type zinc finger protein. The purposes of this study are to elucidate further the functions of a novel zinc finger transcription factor in the grass pea (GpZF) gene involved in the drought stress response in the grass pea (Lathyrus sativus) and to investigate its biochemical and physiological parameters under stress conditions. GpZF was expressed in grass pea. Relative gene expression analysis showed the GpZF gene in independent transgenic lines was more under drought mild and severe treatments (50% and 25% field capacity-FC). Furthermore, overexpression of this gene in grass pea results in more relative water content, free proline, and soluble sugars than the wild-type (WT) plants under 50% and 25% FC stresses. Moreover, in 25% FC, the independent transgenic lines revealed an increase in survival rates and dry weight than the WT plants. GpZF thus implies the positive role in drought stress tolerance in Lathyrus sativus. In conclusion, the transgenic grass pea plants generated in this study could be used to farm arid areas.HighlightGpZF is a positive regulator in drought stress tolerance in grass pea.