Phenolic Compounds, Antioxidant and Antibacterial Activities are Affected by Sulfur Deficiency in Foeniculum vulgare Seeds

Abstract

The reduction in atmospheric inputs of SO 4 2- as a result of stricter regulations of sulfur emission and the depletion in sulfur reserves following the intensification of agricultural production has caused a serious decrease in soil S-concentration. This would markedly affect growth and quality of numerous economically important plants. Foeniculum vulgare or fennel is one of the most cultivated aromatic and medicinal plants, mostly used for their powerful therapeutic effects. Being one of the cultivated species, Foeniculum vulgare could be affected by environmental disturbances like sulfur deficiency. In this work, the poor sulfur supply had a serious impact on the therapeutic quality of fennel seed extracts. At the application of sulfur deficiency, total phenolic compounds of fennel seeds extract decreased by 30% and their total antioxidant activity decreased by 21%. Sulfur starvation also reduced the antibacterial activity of fennel seeds against Staphylococcus aureus, Enterococcus faecalis, and Pseudomonas aeruginosa by increasing the MIC of seed extracts.