In this research, a HPLC analysis, along with transcriptomics tools, was applied to evaluate chitosan and water stress for the prediction of phenolic flavonoids patterns and terpenoid components accumulation in Salvia abrotanoides Karel and S. yangii. The results indicated that the tanshinone contents under drought stress conditions increased 4.2-fold with increasing drought stress intensity in both species. The rosmarinic acid content in the leaves varied from 0.038 to 11.43 mg/g DW. In addition, the flavonoid content was increased (1.8 and 1.4-fold) under mild water deficit conditions with a moderate concentration of chitosan (100 mg L⁻¹). The application of foliar chitosan at 100 and 200 mg L⁻¹ under well-watered and mild stress conditions led to increases in hydroxyl cryptotanshinone (OH-CT) and cryptotanshinone (CT) contents as the major terpenoid components in both species. The expressions of the studied genes (DXS2, HMGR, KSL, 4CL, and TAT) were also noticeably induced by water deficit and variably modulated by the treatment with chitosan. According to our findings, both the drought stress and the application of foliar chitosan altered the expression levels of certain genes. Specifically, we observed changes in the expression levels of DXS and HMGR, which are upstream genes in the MEP and MVA pathways, respectively. Additionally, the expression level of KSL, a downstream gene involved in diterpenoid synthesis, was also affected. Finally, the present investigation confirmed that chitosan treatments and water stress were affected in both the methylerythritol phosphate pathway (MEP) and mevalonate (MVA) pathways, but their commitment to the production of other isoprenoids has to be considered and discussed.

Among traditional Iranian herbs, Perovskia species (a subgenus of Salvia), while being valued ornamentals, are also studied for numerous potential pharmacological and therapeutic aspects. The current study was conducted to assess the effectiveness of two species of arbuscular mycorrhizal fungi (AMF), Funneliformis mosseae and Rhizophagus intraradices, separately and in combination, in terms of the essential oil content and compositions along with the enzymatic and non-enzymatic antioxidants in Salvia abrotanoides and S. yangii in response to three levels of irrigation, including 100% FC as well-watered, 75% FC (moderate irrigation deficit), and 50% FC (severe irrigation deficit). In both species, essential oil content, enzyme antioxidant activities, total phenolics, and flavonoids were increased significantly with the severity of stress; this increase was more pronounced in mycorrhizal inoculated herbs. Furthermore, leaf phosphorus concentration, relative water content, chlorophylls a and b, and total carotenoids decreased in parallel with reducing soil moisture; albeit, AMF inoculation improved the stress symptoms under increasing severity of water restriction compared with their control conditions. In addition, the percentage of root colonization was positively correlated with the relative water content (RWC) and leaf phosphorus concentration. Taking into account the essential oil groups, AMF colonization elevated some essential oil components, such as oxygenated monoterpenes, 1,8-cineol, camphor, and borneol, whereas the main sesquiterpenes, including E-β-caryophyllene and α-humulene, remarkably decreased. Taken together, these findings highlighted the role of symbiosis with AMFs in increasing the tolerance of water deficit stress in S. abrotanoides and S. yangii and improving their essential oil composition.

Background Type 2 diabetes (T2D) is a complex metabolic disorder characterized by impaired glucose regulation and insulin resistance and frequently accompanied by obesity and dyslipidemia. The search for novel therapeutic agents to manage these metabolic parameters remains ongoing. Pepper fruit (cv. Meein) extract, a non-pungent Capsicum variant, has been proposed as a potential intervention for metabolic dysfunctions associated with T2D. Methods This study investigated the impact of pepper fruit extract on metabolic parameters using a db/db diabetic mouse model. Fifty mice were randomly assigned to five groups (n = 10 per group): a normal control group, a diabetic control group (db/db), a positive control group treated with acarbose (50 mg/kg), and two treatment groups receiving either 150 mg/kg or 300 mg/kg of "Meein" extract. The intervention lasted for 10 weeks. Key metabolic indicators, including body weight, blood glucose levels, oral glucose tolerance (OGTT), lipid profile (triglycerides and cholesterol), and insulin concentrations, are measured to assess the extract's therapeutic potential. Results Treatment with "Meein" extract resulted in significant reductions in body weight, with the 300 mg/kg group exhibiting a 10.6% decrease compared to the diabetic control. Both treatment groups demonstrated reductions in blood glucose, with the 150 mg/kg group showing statistically significant improvements. OGTT results did not indicate significant enhancement in glucose tolerance, and lipid profiles, including triglyceride and cholesterol levels, did not show significant changes following extract administration. Notably, the extract exerted a marked effect on insulin levels: while the diabetic control group showed hyperinsulinemia, insulin concentrations in the extract-treated groups were significantly reduced, with the 300 mg/kg group achieving a 38% decrease, indicative of improved insulin sensitivity. Conclusion These findings suggest that ‘Meein’ extract may have potential for managing obesity and improving insulin sensitivity in T2D. Importantly, no significant effects on OGTT or lipid profiles were observed in this study. Further research is necessary to clarify the extract’s effects on glucose metabolism and lipid regulation.