Zinc and phosphorus fertilization in Galanthus elwesii Hook: Changes in the total alkaloid, flavonoid, and phenolic content, and evaluation of anti-cancer, anti-microbial, and antioxidant activities

Abstract

Galanthus elwesii Hook belongs to the Amaryllidaceae family and is an ornamental plant that naturally spreads in the region between Turkey and Europe. It also contains bioactive compounds in the nutraceutical and pharmaceutical field. The objective of this study was to evaluate the effects of zinc (Zn) and phosphorus (P) in the synthesis of alkaloid compounds and bioactive properties in G. elwesii. The plants were subjected to three different concentrations of zinc (2.5, 5, and 10 mg kg−1), and phosphorus (3, 6, and 12 mg kg−1), and compared with the control. Two harvests were evaluated, between 2020 and 2021. The total phenolic content (TPC), total flavonoid content (TFC), and total alkaloid content (TAC) were identified by Folin-Ciocalteu, aluminum chloride, and bromocresol green-complex assays, respectively. TPC (85.09 ± 0.4 mg QE/g), TFC (267.7 ± 1.6 mg GAE/g), and TAC (320.58 ± 2.4 mg CoE/g) were the highest in the treatments of Zn 10, Zn 10 and Zn 2.5 + P 3 mg kg−1, respectively. RP-HPLC analysis revealed that, compared with the control group, galanthamine, and lycorine synthesis were increased by 755% (Zn 5 + P 3 mg kg−1) and 815% (Zn 2.5 mg kg−1) respectively. The highest antioxidant activities of were found to be 80.21% (10 mg kg−1 Zn) and 78.05% (2.5 mg kg−1Zn + 3mg kg−1 P), respectively. The extracts exhibit strong anti-microbial activity, particularly against Bacillus subtilis, Candida albicans, Pseudomonas aeruginosa, Saccharomyces cerevisiae, and Staphylococcus aureus. The MCF-7 cell line was used to investigate its anti-cancer activity properties. The MTT assay result was obtained from extracts treated with Zn 10 mg kg−1 for the best cytotoxic activity against the MCF-7 cell line (IC50 value: 31.57 ± 0.70 μg/mL).