Investigation of antioxidant, antihelminthic activities and toxicities of Onopordum bracteatum extracts

Plants stand out in terms of eliminating the negative effects of ROS with different antioxidant substances (secondary metabolites) that they produce compared to other living things. Vegetable antioxidants are a very important tool that appeared in nature to combat the active by-products of aerobic metabolism. Saltwater shrimp lethality test is a simple, reliable and convenient method used to determine the toxicity of plant extracts. Helminths (worms) are animals specialized to make cells, tissues and organs, and they live as parasites in the body of living things, causing diseases. Anthelminthic drugs are usually used to control parasites found in the digestive tract. In this study, the antioxidant activities of methanol, acetone and water extracts of Onopordum bracteatum distributed in the flora of Turkey were investigated and the total phenolic, total flavonoid and total tannin amounts in the relevant extracts were determined. In addition, anthelmintic activities of methanol and water extracts as well as toxicities of water extracts were determined. The antioxidant activity of the extracts was determined by DPPH free radical scavenging, ABTS free radical scavenging, β-carotene/linoleic acid, copper (CUPRAC) and iron reduction (FRAP) methods. When the antioxidant activities of the extracts were compared, it was seen that the general antioxidant activity of the leaf methanol extract was higher than the other extracts. In addition, by using Folin-Ciocalteu, aluminum chloride and vanillin reagent, the total phenolic, flavonoid and tannin contents were determined, respectively. Extracts with the highest total phenolic, flavonoid and tannin content (5.78±0.24 mg GAE/g), leaf acetone (32.17±0.82 mg QE/g) and floral acetone (16.41±1 ,30 mg CE/g). The brine shrimp (Artemia salina L.) lethality test was used to examine the possible toxic effects of the extracts. Flower water extract showed the highest toxic effect with a lethality value of 97.2±2.29%. The anthelmintic activity test was performed by recording the lethality of plant extracts at different concentrations on Tubifex tubifex. Leaf methanol extract showed the highest anthelmintic activity. It is believed that the data obtained from this study will contribute to the development of research on the use of products obtained from plants in many fields such as medicine and alternative medicine. Key Words: Onopordum bracteatum, Antioxidant, Anthelminthic, Artemia salina