Extraction of polyphenol and flavonoid compounds from Grammosciadium Platycarpum Boiss and their microencapsulation in an alginate hydrogel.

The aim of this study was to extract and encapsulate the phenolic and flavonoid compounds of wild dill (Grammosciadium Platycarpum Boiss) in sodium alginate hydrogel. In this study, phenol and flavonoid compounds were extracted from Grammosciadium Platycarpum Boiss and then used for encapsulation at three concentrations of 1, 2 and 3%) in sodium alginate with three concentrations of 1.5, 2 and 3%. In the next step, antioxidant activity (total antioxidant, DPPH free radical scavenging capacity, OH radical scavenging, reducing power), loading capacity of phenolic compounds of Grammosciadium Platycarpum Boiss extract in alginate hydrogel, encapsulation efficiency and process efficiency, were evaluated. Also, structural properties of encapsulated material including chemical structure using infrared spectroscopy were measured. The ability to preserve phenolic compounds and antioxidant properties of the product during 30 days of storage in different environmental conditions (light and dark, and temperature 25 ° C and 4-7 °C) were also evaluated. The results showed the maximum loading capacity of 1.178 mg as gallic acid per gram of extract was obtained for alginate hydrogel containing 3% extract. In addition, it was found that by using this method, a high coating efficiency of about 75% was obtained. The results also revealed a significant difference (P<0.05) in the ability to maintain antioxidant activity against environmental conditions, for hydrogels containing different amounts of extract during 30 days of storage. Similar results obtained with respect to the ability of phenolic compounds retention during storage in hydrogels containing the extract, the maximum retention of total antioxidant properties, free radical scavenging of DPPH, free radical scavenging of OH and reducing power under different storage conditions, were observed for hydrogels containing 2% extract. The greatest reduction in antioxidant properties was observed for hydrogels containing 1% extract under artificial light conditions. The ability to maintain the antioxidant property of the was observed in the artificial light condition about 55/18% and in the dark conditions about 74/15%.the rate of free radical DPPH in artificial lighting conditions accounted for about 36/42 %, and about 84/15 % in the dark conditions. The rate of free radical OH in artificial lighting conditions accounted about 44/11% and about 68/34% in the dark conditions. The rate of power regenerative in artificial lighting conditions was 63/53 % and was estimated at 75/83% in the dark conditions. In this study it was found that 2% alginate containing 2% extract has the best encapsulation and has the highest retention of phenolic compounds and antioxidant properties during storage.