Researching on Optimization and Evaluation Some Biological Activities of Polyphenol Extract from Avocado Seeds...

Optimization of polyphenol extraction from avocado seeds and systematic evaluation of the bioactivity of fractions in two different solvents. This research aimed to optimize the extract parameters of polyphenol from avocado seed and evaluate antimicrobial and antioxidant activities of crude polyphenol extract and its fraction in dichloromethane and ethyl acetate. The study utilized ultrasound-assisted extraction (UAE) and response surface methodology (RSM) to optimize extraction parameters that were ethanol 61.082 % concentration, an extraction temperature of 59.986 °C, and an extraction time of 3.09 hours. The crude polyphenol extract contained 42.208 mg GAE/g DW and antioxidant activity of extracts were expressed as percentage of DPPH radicals inhibition with an IC₅₀ value of 117 μg/mL. Following the liquid-liquid fractionation of the crude extract with dichloromethane and ethyl acetate obtained ethyl acetate fraction was found to content 74.65 mg GAE/g DW and showed the highest antioxidant activity, with an IC₅₀ value of 62.04 μg/mL. The antimicrobial tests against some pathogenic bacteria showed that both the crude and ethyl acetate extracts were effective against Escherichia coli and Salmonella spp. Notably, the crude extract inhibited Aspergillus flavus at 100 mg/mL, while the ethyl acetate fraction did not exhibit inhibitory activity at the concentrations tested.