Eco-Green Conversion of Watermelon Peels to Single Cell Oils Using a Unique Oleaginous Fungus: Lichtheimia corymbifera AH13

Watermelon peel waste (WPW) is being used for first time in single cell oils (SCOs) production via a promising oleaginous fungus Lichtheimia corymbifera which was isolated from Egyptian ecosystem. Pretreatments of WPW were carried out by mechanical, physical and chemical methods; the most potent pretreatment was selected according to total reducing sugar and total lipid production. Accordingly, the mechanical ptetreatment of WPW was distinctly the best pretreatment method for SCOs production from L. corymbifera . Taguchi design clarified that the most optimal culture conditions were 35 °C and pH 7.0 for 4 days by which the highest potential of SCOs and lipid content was yielded (2.93 gl −1 and 39.56% respectively). Mechanical treatment revealed that the dominant fatty acid was palmitic and oleic acids with 41.98 and 34.65% respectively with appearance of γ linolenic acid (GLA) at low concentration 1.43%. Finally, this study showed that WPW was used as a natural, effective, economic, ecofriendly and integrated substrate without adding any outsource nutrients to produce sustainable SCOs with low cost production. Graphic Abstract