Characterization and Metabolite Profiling of Bioactive Compounds of Pink and White Aggregatum Onion Genotypes

Aggregatum onion (Allium cepa L. var. aggregatum Don.) is a noticeable commercial crop widely grown and consumed in southern India. This study focuses on the phytochemical composition of two high yielding onion genotypes through initial phytochemical screening and gas chromatography-mass spectrometry (GC-MS) analysis. The experiment was conducted at Tamil Nadu Agricultural University, Coimbatore from 2022 to 2024, and it included ten aggregatum onion genotypes. The findings reveal that between various genotypes of pink and white aggregatum onion, CO (On) 5 of the pink genotype and ACA 2 of the white genotype outer performed compared to other genotypes in several parameters. The bulb weight, equatorial diameter, plant height, polar diameter, no of leaves, leaf length(cm), leaf girth, foliage weight, bulb length (cm), bulb width (cm) and bulb circumference of CO (On) 5 and ACA 2’s showed a significant and positive correlation with yield. A wide range of metabolites, including aldehydes, alcohol, ketone boron compounds and amines with variations observed among the onion genotypes. The CO (On) 5 has the highest area percentage of 95.81 with higher concentrations of ketone 15.70%, aldehyde 13.10%, lactone 7.89%, alcohol and diol both 7.8% and amine 5.2%. ACA 2 shows the second highest area of 91.26% with higher concentrations of amine (5.26%), lactone (7.89%), alcohol and diol (7.8%), ketone (15.70%), and aldehyde (13.10%). These findings enhance selective breeding efforts aimed at important new information about the phytochemical and nutritional content of onions. They also highlight the potential of these onions for use as high-quality functional foods.