Chemical composition and biological activity of two Lactarius species from Serbia.

Abstract

Mushrooms are highly appreciated for their nutritional value and therapeutic effects. They have found wide application in pharmacy, medicine and as nutraceuticals, mostly due to the synergistic activity of their bioactive compounds. This study aimed to investigate the chemical composition and antioxidant, antibacterial, antibiofilm, and cytotoxic potential of L. piperatus and L. vellereus wild growing mushrooms from Serbia. Mannitol and trehalose were the most abundant free sugars and malic and citric acid were the major organic acids detected. The four tocopherol isoforms were found in L. piperatus, and the β-tocopherol was the only tocopherol isoform found in the L. vellereus fruiting body. Regarding phenolic compounds, cinnamic and protocatechinic acids were identified in the prepared methanolic and ethanolic extracts, which displayed antioxidant activity through the inhibition of thiobarbituric acid reactive substances (TBARS) formation (IC50 0.30-1.39 mg/mL). Antibacterial activity of Lactarius ethanolic and methanolic extracts was investigated against bacteria isolated from tonsils from the patient with chronic tonsillitis. All tested extracts demonstrated promising results regarding antibacterial and antibiofim activity. In both extracts, the most promising activity was observed for Streptococcus spp. (0.40–6.25 mg/mL as the minimal inhibitory concentration). Ethanolic extracts of tested mushrooms showed a stronger potential to inhibit the formation of Staphylococcus aureus biofilm then methanolic. L. vellereus ethanolic extract showed highest inhibition activity (86%) against S. aureus biofilm formation. Citotoxic potential of L. piperatus and L. vellereus extracts were examined against four tumor cell lines (HeLa, MCF-7, HepG2, NCI-H460) and porcine liver primary culture - PLP2. The most promising cytotoxic effect was caused by the L. vellereus ethanolic extract on cervical carcinoma cell line (HeLa). However, extensive screening of biological activities is needed in future studies that will allow the exploitation of these mushrooms at an industrial level, taking advantage of its benefits for human health.