Influence of different drying methods on antioxidant activity, total phenol, and phenolic compounds of myrtle (Myrtus communis L.) fruits

The antioxidant activity increased from 25.43% to 83.55% when dried at room temperature. Methanolic extracts of the all dried berries showed strong antioxidant activity against DPPH radicals in comparison to fresh samples. The highest total phenolics (135.07 mg/100 g) were detected in microwave-dried fruit, and followed by (115.63 mg/100 g) in samples dried at room temperature. 1,2-Dihydroxybenzene (118.57 mg/100 g), catechin (52.71 mg/100 g), and 3,4-dihydroxybenzoic acid (29.01 mg/100 g) in fresh berries were increased to 251.43, 158.98, and 110.99 mg/100 g in microwave dried ones, respectively. However, only gallic acid contents decreased from 131.54 mg/100 g in fresh samples to 23.74 mg/100 g in microwave treated one. It can be inferred that dried myrtle fruit is good source of antioxidant and phenolic compounds. Myrtle fruit can be effectively used for the recovery of bioactive compounds which have useful functional properties and can be employed in the development of functional foods and nutraceuticals. Practical applications Drying processes are also applied to extract bioactive compounds from plant matrix (seed, fruit, leaf, etc.). Different drying methods can cause changes in the contents and availability of biologically important compounds from these matrices. Microwave energy and oven drying have been widely used in various processes. The results of current study are hence useful for the optimal processing of plant materials for the recovery of different phytochemicals and their use.

Automated summary

The study demonstrated that drying processes significantly enhance the antioxidant activity and total phenolic content of myrtle fruit, especially microwave drying has a significant impact on the alteration of its chemical composition.