Effect of Novel Aspergillus and Neurospora Species-Based Additive on Ensiling Parameters and Biomethane Potential of Sugar Beet Leaves

Abstract

Research on additives that improve the quality of silages for an enhanced and sustainable biogas production are limited in the literature. Frequently used additives such as lactic acid bacteria enhance the quality of silages but have no significant effect on biogas yield. This study investigated the effect of a new enzymatic additive on the quality of ensiling and BMP of sugar beet leaves. Sugar beet leaves were ensiled with and without the additive (Aspergillus- and Neurospora-based additive) in ratios of 50:1 (A50:1), 150:1 (B150:1), and 500:1 (C500:1) (gsubstrate/gadditive) for 370 days at ambient temperature. Results showed that silages with additive had lower yeast activity and increased biodegradability compared to silages without additive (control). The additive increased the BMP by 45.35%, 24.23%, and 21.69% in silages A50:1, B150:1, and C500:1 respectively, compared to silages without additive (control). Although the novel enzyme is in its early stage, the results indicate that it has a potential for practical application at an additive to substrate ratio (g/g) of 1:50. The use of sugar beet leaves and the novel enzyme for biogas production forms part of the circular economy since it involves the use of wastes for clean energy production.