Investigation of the effect of polarity of different solvents and Times to extract the effective compounds of sour lemon peel extract by ultrasound

The ultrasound process is a non-thermal method of extraction, and due to its effective effects on food storage and processing its use is increasing. Therefore, the aim of current study was to investigate the effect of ultrasound waves on phenolic and flavonoid compounds extraction of lemon peel extract. In this method in order to evaluate the phenol and flavonoids extraction and to assess the inhibitory power of DPPH free radicals, three different water solvents, 70% ethanol and 80% methanol were used. Then, the best solvent for the extraction of these compounds at of 30, 60and 90 moments were compared. The software used for analysis of variance and comparison of means was SPSS. According to the results, the strongest and weakest solvent for the extraction of bioactive compounds were 70% ethanol and water, which was 8.202 and 6.95 mg, equal to Gallic acid per grams of dry extract of phenolic compounds, 4.61 and 3.74 mg equal to quercetin grams of compound flavonoids dry matter and 87.468 and 70.213 percent of the inhibitory power of DPPH-free radicals. In 70% ethanol solvent, a significant difference was observed between 30, 60 and 90 moments for extraction of effective compounds, and 90 and 30 minutes, respectively, had the highest and lowest extraction rates of the compounds, respectively. In each extraction method, the amount of extraction of bioactive compounds was different depending on the solvent and 70% ethanol solvent was the best extraction method.