Molecular Characterization and Metabolite Profiling of Philippine Allium sativum Linn.: Ilocos Pink

Abstract

Ilocos Pink garlic (IPG) is a local garlic variety found in Ilocos Norte, Philippines. Recently known for its moderate beta-adrenergic receptor inhibitory activity in vivo, there is still a limited number of studies describing its genetic and metabolite profile to distinguish it from other garlic varieties. In this study, genetic markers of IPG were identified using sequence-related amplified polymorphism (SRAP) analysis. Ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry followed by principal component analysis (PCA) was used to discriminate IPG’s metabolites from Ilocos Native garlic. Based on the degree of brown-stripe pigmentation on their outer skin, IPG samples can be classified into three – light, moderate, and heavy pigmentation. These subgroups were found to share seven SRAP marker pairs – namely,ME1-EM1 (at 300bp), ME1-EM4 (at 400bp), ME2-EM3 (500bp), ME3-EM1 (300bp), ME3-EM2(at 400bp), ME3-EM4 (at 200bp), and ME5-EM2 (at 300bp). Unique SRAP marker pairs were also observed between subgroups. PCA revealed Ilocos Native garlic to be discriminated from the IPG groups, but the marker matrix tool showed mere differences in concentrations except m/z247.129 at RT 1.40. Concentration-wise, nine markers may be proposed to discriminate IPG light from IPG moderate and heavy, seven of which are putatively identified as saponins. These findings suggest that SRAP markers can effectively discriminate IPG into subgroups, whereas metabolite profiling may provide little insight into the differences between IPG and Ilocos Native garlic.