Optimization of Extraction Conditions for Biological Attributes of Newly Developed NARC-G1 Garlic Using Response Surface Methodology and Its GC-MS Characterization.

Abstract

The present paper is a comprehensive study on the optimization of ultrasonic assisted extraction and characterization of valued components from the newly developed garlic cultivar NARC-G1. The response surface methodology was employed to optimize the extraction time, solvent-to-solid ratio and extraction temperature, for optimal total phenolic contents (TPC), DPPH radical scavenging activity, α-amylase inhibition, and α-glucosidase inhibition. Under the optimized conditions (23 min extraction time, 60 °C temperature, and 39 : 1 solvent-to-solute ratio) the optimal TPC (13.76 mg GAE/g), DPPH radical scavenging activity (62.76 %), α-amylase inhibition (71.43 %), and α-glucosidase inhibition (79.43 %) were obtained. Significant correlations were observed between actual values and predicted values for the selected responses. Gas chromatography-mass spectrometry (GC-MS), revealed 26 high-value bioactives, with diallyl disulphide being the most abundant (16.22 %), followed by 2,3-dihydro-3,5-dihydroxy-6-methyl, 4H-pyran-4-one and 5-Hydroxymethylfurfural. Additionally, in silico investigation indicated that stigmasterol, arbutin, squalene, α-tocopherol and linoleic acid were responsible for antihyperglycemic potential. Moreover, antimicrobial activity revealed that S. mutans (19.25±1.98 mm) and L. monocytogenes (19.34±2.04 mm) were the most sensitive, while P. aeruginosa was the least sensitive bacterial strains against the optimized NARC-G1 garlic extract. This research effectively explains the optimal recovery of high-valued components from NARC-G1 and may contribute to nutra-pharmaceutical and functional food developments.