Do vermicompost applications improve pharmaceutically important alkaloids, growth performance, phenolic content, and defense enzyme activities in summer snowflake ( Leucojum aestivum L.)?

Abstract Leucojum aestivum L. includes galanthamine and lycorine, which are two pharmaceutically valuable alkaloids. Vermicompost (VC), an organic waste product created by earthworms enhances soil quality and can improve the medicinal quality of the plant that is crucial to the pharmaceutical industry. Purpose The aim of this study was to determine the effects of four different VC concentrations (5%, 10%, 25%, and 50%) on L. aestivum growth parameters, alkaloid levels (galanthamine and lycorine), total phenol-flavonoid content, free radical scavenging potential, and defense enzyme activities (SOD and CAT) compared to control (no VC). Methods A 2,2-diphenyl-1-picrylhydrazil (DPPH) radical assay was performed for antioxidant activity. Folin-Ciocaltaeu and aluminum chloride colorimetric methods were applied for the determination of total phenol and flavonoid content, respectively. Alkaloid amounts (galanthamine and lycorine) were analyzed by the HPLC-DAD system. Results The width, length, and fresh weight of the leaves were improved by 10% VC treatment. The highest total phenolic content was found in bulbs and leaves treated with 50% VC. HPLC-DAD analysis of alkaloids showed that 10% and 50% VC treatments contained the most galanthamine in the bulb and leaf extracts, respectively. The application of 25% VC was the most efficient in terms of lycorine content in both extracts. CAT activity was elevated at 10%, 25%, and 50% VC. Conclusions Based on the growth performance and galanthamine content of the bulbs and leaves, it can be concluded that a 10% VC application was the most effective in the cultivation of L. aestivum.