Biovalorization of hemp seed oil cake after biological treatment with Trametes versicolor and Humicola grisea

Kao nusproizvod u procesu proizvodnje ulja hladnim prešanjem nastaje pogača u kojoj zaostaju određene količine ulja, a koja sadrži proteine, vlakna, mineralne tvari i druge sastojke. U ovome radu provedena je biološka obrada konopljine pogače s dva mikroorganizma, Trametes versicolor i Humicola grisea, u uvjetima fermentacije na čvrstim nosačima. Analiziran je kemijski sastav konopljine pogače (udio vlakana, proteina, masti, mineralnih tvari, ukupnog organskog ugljika) prije obrade i nakon deset dana obrade. Svakodnevno su analizirane i koncentracije jednostavnih šećera u vodenim ekstraktima pogača, te su mjerene volumne aktivnosti enzima lipaze. Na temelju dobivenih rezultata zaključeno je da nakon obrade s oba mikroroganizma dolazi do porasta udjela mineralnih tvari, proteina, ukupnog organskog ugljika i vlakana u konopljinoj pogači. No, unatoč tome što je detektirano smanjenje udjela masti, nisu zabilježene vrijednosti volumnih aktivnosti lipaza značajnije za njenu daljnju primjenu. Rezultati analize šećera ukazuju da oba mikroorganizma hidroliziraju saharozu do glukoze i fruktoze, te troše glukozu za svoj rast, te je dokazano da, za razliku od H. grisea, T. versicolor ne metabolizira fruktozu.In the production of cold-pressed oil, a cake is made as a by-product in which certain amount of oil is left behind, but also contains proteins, fibers, minerals and other ingredients. In this work, biological treatment of hemp oil cake has been carried out with two microorganisms, Trametes versicolor and Humicola grisea, using fungal-based solid-state technology. Before and after biological treatment of hemp oil cake, the content of fibers, total proteins, ether extracts, ash and total organic carbon were analyzed. During the treatment, concentration of simple sugars in aqueous extracts of cake as well as volume activity of enzyme lipase were measured. Based on the obtained results, after biological treatment with both microorganisms, it can be concluded that the content of ash, total proteins, total organic carbon and fibers increased. Despite the fact that the content of ether extracts decreased, amounts of lipase significant for its further applications, weren't recorded. The results of sugar analysis suggest that the both microorganisms hydrolyze sucrose to glucose and fructose, and utilize glucose for its growth, whereas it is shown that, unlike H. grisea, T. versicolor doesn't methabolise fructose