Total phenolic contents and antioxidant activity of some herbs traditionally used in Libya as food flavoring [electronic resource].

Includes references.

There is currently an upsurge of interest in phytochemicals as new sources of natural antioxidants to use them in foods and pharmaceutical preparations in order to replace synthetic antioxidants. which are being restricted due to their potential health risks and toxicity. Total equivalent antioxidant capacities (TEAC) and phenolic contents of four herbs extracts from tow botanical families (Lamiaceae and Caryophyllaceae) grown in Libya were investigated and compared to green tea. The total antioxidant capacity was estimated by the DPPH' (1. 1-diphenyl-2-picrylhydrazyl radical) and expressed as TEAC. Results revealed that the total phenolic content as measured using a Folin-Ciocalteu assay, ranged from 29.24to 79.34 mg of gallic acid equivalents (GAE)/ g (dw) while the green tea contained 116.33mg (GAE)/g (dw) as a control. The highest total phenolic content was observed in Mentha spicata L. followed by R. officinalis L., T. capitatus L., (79.34 , 51,67 and 49.70 mg (GAE)/ g (dw) respectively), while the lowest content was found in P. arabica L. (29.24 mg GAE/ g (dw). The highest TEAC value (μmol TE/g extract) was obtained from M. spicata L. (105 μmol trolox/g(dw)While the lowest value was observed from P. arabica L. (32.10). Data also revealed that the positive linear correlation between the antioxidant activity and total phenolic content in methanolic extract (R² = 0.9449) for all studied herbs. All extracts exhibited antioxidant activity descending in the following order C. sinesis L. > M. spicata L. > R. officinalis L > T. capitatus L. and P. arabica L. Based on these obtained results that two herbs, namely, M. spicata L. and R. officinalis L., were identified as sources of free radical scavenging compounds. As they contain good sources of phenolic compounds which used in different applications to preserve foods,

Summary in Arabic.

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