Separation and Identification of Antioxidants and Aldose Reductase Inhibitors in Lepechinia meyenii (Walp.) Epling

Abstract

We previously reported that Lepechinia meyenii (Walp.) Epling has antioxidant and aldose reductase (AR) inhibitory activities. In this study, L. meyenii was extracted in a 50% MeOH and CH2Cl2/MeOH system. The active extracts of MeOH and 50% MeOH were subjected to fractionation, followed by separation using high-speed counter-current chromatography (HSCCC) and preparative HPLC. Separation and identification revealed the presence of caffeic acid, hesperidin, rosmarinic acid, diosmin, methyl rosmarinate, diosmetin, and butyl rosmarinate. Of these, rosmarinic acid, methyl rosmarinate, and butyl rosmarinate possessed remarkable antioxidant and AR inhibitory activities. The other compounds were less active. In particular, rosmarinic acid is the key contributor to the antioxidant and AR inhibitory activities of L. meyenii; it is rich in the MeOH extract (333.84 mg/g) and 50% MeOH extract (135.41 mg/g) of L. meyenii and is especially abundant in the EtOAc and n-BuOH fractions (373.71–804.07 mg/g) of the MeOH and 50% MeOH extracts. The results clarified the basis of antioxidant and AR inhibitory activity of L. meyenii, adding scientific evidence supporting its traditional use as an anti-diabetic herbal medicine. The HSCCC separation method established in this study can be used for the preparative separation of rosmarinic acid from natural products.

Controlled Production of Carnosic Acid and Carnosol in Cell Suspensions of Lepechinia meyenii Treated with Different Elicitors and Biosynthetic Precursors

“…Despite the endogenous amounts of these diterpenes were higher in the intact leaves than in the in vitro cultures of L. meyenii , several factors should be considered for their extraction. One of these factors is regarded to continuous extraction from wild plants because of current regulation on plant diversity protection [13–14] . Other factor is referred to the complexity to acquire high purity compounds from green tissues including those obtained from in vitro cultures (regenerated shoots) because of the inherent protocols of extraction and separation.…”

“…However, it is known that the biosynthesis of this diterpene depends on the developmental stage and specific types of stress such as saline stress, high temperature, and hormonal treatment [1] . As is known, several plants from the Lepechinia genus produce a wide spectrum of bioactive diterpenes [13–15] . Lepechinia meyenii is a medicinal plant with ample distribution in South America including Argentina, Bolivia, and Peru [13] .…”

“…[1] As is known, several plants from the Lepechinia genus produce a wide spectrum of bioactive diterpenes. [13][14][15] Lepechinia meyenii is a medicinal plant with ample distribution in South America including Argentina, Bolivia, and Peru. [13] The leaf infusion of this plant is destined for the treatment of common disorders such as diabetes, and as an analgesic for the mitigation of stomachache and joints.…”

“…[13][14][15] Lepechinia meyenii is a medicinal plant with ample distribution in South America including Argentina, Bolivia, and Peru. [13] The leaf infusion of this plant is destined for the treatment of common disorders such as diabetes, and as an analgesic for the mitigation of stomachache and joints. [14] The plant is considered as a valuable source of CA and CS among other antioxidants with biological activity.…”

Screening and Evaluation of Active Compounds in Polyphenol Mixtures by a Novel AAPH Offline HPLC Method and Its Application

“…Epling ( L. meyenii ), a member of the Lamiaceae family, is indigenous to Argentina, Bolivia, and Peru, and its herbal infusion is commonly used in Peru as a traditional medicine to treat a range of conditions, including diabetes, cough, inflammation, diarrhea, spasms, stomach discomfort, and joint and stomach pain [ 13 ]. In our previous study, L. meyenii extract was found to have good antioxidant activity, and seven main components were isolated and identified from its extract; however, their anti-lipid peroxidation activity was unknown, which prompted us to use offline HPLC to further clarify the anti-lipid peroxidation activity and composition of L. meyenii [ 14 ].…”