Investigation of morpho-anatomical, molecular, GC/Q-ToF, and LC/Q-ToF characterization of Salvia mellifera (black sage), Saliva apiana (white sage) and their varieties

Abstract

Salvia mellifera (black sage) and Salvia apiana (white sage) are known for complex introgressive hybridization. Morphological variations between these two Salvia species and their varieties present overlapping characters that may cause confusion in identifying the genuine species in nature. Since these plants may be candidates for investigation of botanical-based drugs, this study aimed to differentiate the two Salvia species from each other and to group the closely resembling varieties. With many Salvia species offering health benefits, the morphological analysis and chemical fingerprinting of these two species will benefit their potential consideration for further evaluation of their health benefits.Detailed histology, histochemistry, molecular, and chemical characterizations were used to identify distinguishing characteristics of genuine S. mellifera and S. apiana along with two varieties resembling S. mellifera or S. apiana. Macroscopic and microscopic characterization of leaf lamina and types of trichomes can differentiate the morphology of S. mellifera from S. apiana. The histochemical analysis of glandular trichomes revealed the presence of flavonoids, terpenes, and other common secondary metabolites. Micropatterns of calcium oxalate crystals were identified as being characteristic and aiding in differentiation.Even though the external morphological characters of the two varieties resemble an intermediate between S. mellifera and S. apiana, chemical qualitative analyses via LC/Q-ToF and GC/Q-ToF indicate a chemical fingerprint more similar to that of S. apiana. This is a detailed analysis using various approaches including morpho-anatomy, trichome micromorphology, molecular analysis, and chemical similarities to identify and differentiate between S. mellifera, S. apiana, and their close varieties.