Hossein Abbaspour

This study investigates the relationships between genetic diversity, environmental factors, and essential oil composition in Myrtus communis L., an evergreen medicinal shrub. Three populations in Lorestan Province, Iran (Cham Mord, Kaka Reza, Sepid Dasht) were analyzed using molecular and chemical techniques. Genetic diversity was assessed using Inter-Simple Sequence Repeat (ISSR) and Start Codon Targeted (SCoT) markers. ISSR (eight primers, 81 loci) showed highest diversity in Cham Mord (Shannon I = 0.26), while SCoT (eight primers, 71 loci) indicated Kaka Reza had highest diversity (I = 0.27). PCoA and cluster analysis under both markers showed Cham Mord was genetically distinct, with lowest genetic distance between Kaka Reza and Sepid Dasht (0.259) and highest between Cham Mord and Sepid Dasht (0.332). Gas Chromatography-Mass Spectrometry identified 37 essential oil compounds with significant variation. Cham Mord had higher α-pinene (72.05%) than Kaka Reza (22.45%) and Sepid Dasht (6.56%). Sepid Dasht showed highest oil yield, linked to lower altitude, higher phosphorus (13.8%) and organic carbon (1.24%), and lower salinity (EC = 0.24 ds m^-1). Kaka Reza, with higher salinity (EC = 0.41 ds m^-1) and sodium (19 mg l^-1), had the lowest yield. Essential oil-based clustering grouped Cham Mord and Kaka Reza, separating Sepid Dasht, matching SCoT patterns. Results reveal strong correlation between genetic diversity, oil profiles, and environmental factors including altitude, salinity, sodium, phosphorus, and organic carbon. Altitude inversely related to oil yield. Findings highlight local adaptation and phenotypic plasticity in M. communis chemodiversity, offering insights for conservation, sustainable use, and selection for medicinal and agricultural uses. Further studies on gene expression mechanisms of oil biosynthesis under varying environments are recommended.

With the extensive utilization of nanotechnology, silver nanoparticles (AgNPs) are prevalent nanomaterials that may entail ecological risks by their potential translocation into plant systems. The present study investigated the physiological and molecular responses of basil seedlings (Ocimum basilicum) subjected to AgNPs or silver nitrate (AgNO3) for 7 days. The seedlings were treated with 0, 4, 10, or 40 mg/L of AgNO3 or AgNPs in Hoagland’s solution. Both treatments resulted in significant accumulation of Ag in the roots and shoots, with higher levels in the roots of AgNO3-treated seedlings. AgNPs increased plant biomass at 4 mg/L, while AgNO3 decreased it at all concentrations. Both treatments reduced the total chlorophyll, carotenoids, and carbohydrates, with more pronounced effects in AgNO3-treated seedlings. Both treatments also induced oxidative stress, as indicated by increased levels of H2O2, MD, and proline, and enhanced activity of antioxidant enzymes SOD, CAT, and APX. However, these responses were more evident in AgNO3-treated seedlings, especially at higher concentrations. Quantitative real-time PCR analysis revealed that both treatments induced the upregulation of genes encoding oxidative stress tolerance-related enzymes, such as FSD1, MSD1, CSD1, CATa, CATb, APXa and APXb, in the basil seedling shoots. These results suggest that AgNPs are less toxic to basil plants than AgNO3 and that basil plants can activate physiological and molecular mechanisms to cope with Ag-induced oxidative stress.

Background: The manipulation of mineral nutrition may affect secondary metabolite production and thus determine the nutritional value of food/medicinal plants. Objectives: The present study investigated the impact of nitrogen supply on the production of secondary metabolites and physiological parameters of Hypericum androsaemum plants grown in sand culture. Methods: Four-week plants were irrigated by full-strength Hoagland solution (control), nitrate was reduced to 1/3, and no nitrate was provided for 14 days. Results: The growth of shoots was inhibited by nitrate limitation, but root growth was stimulated. Soluble proteins and water content were significantly affected by nitrate deficiency. Antioxidative enzyme activities (ascorbate peroxidase (APX) and superoxide dismutase (SOD)) were increased due to nitrate deficiency. Treatment of plants with NO3- deficiency caused an increase in total soluble phenols and phenylalanine ammonia-lyase (PAL) activity, while flavonoid content was mainly elevated by NO3- deficiency. At the level of specific metabolites, NO3- deficiency positively affected hypericin and pseudohypericin content but decreased hyperforin content. The expression of the putative gene for hypericin biosynthesis (hyp-1) was up-regulated in response to nitrate deficiency. Conclusions: The results demonstrated that the nitrogen deficiency in the H. androsaemum plant positively affected the antioxidant system, valuable phenols, and secondary metabolites.

Background: Hypericin is a polyphenolic compound derived from Hypericum perforatum that exhibits anticancer activity in various cancer cell types. The molecular mechanisms of hypericin action on breast cancer cells are unclear. We investigated the effects of hypericin on MCF7 human breast cancer cells and the potential role of miR21 and miR34a in mediating these effects. Methods and Results: We evaluated the cell viability of MCF7 cells exposed to different concentrations of hypericin for 24 and 48 hours by XTT assay. e treated MCF7 cells with 5 µg/mL concentration of hypericin for 24 hours. We then measured the expression levels of miR21, miR34a, and their target genes PTEN, BCL2, TP53, and CDK4 at both mRNA and protein levels by qRT-PCR and western blotting. Hypericin decreased the cell viability and increased the apoptosis rate of MCF7 cells in a dose- and time-dependent manner. Hypericin also modulated the expression levels of miR21 and miR34a in MCF7 cells. Hypericin upregulated the expression levels of PTEN and TP53 and downregulated the expression levels of BCL2 and CDK4 in MCF7 cells. The changes in gene expression were consistent with the changes in protein expression. Conclusion: Hypericin induces anticancer effects on MCF7 human breast cancer cells by reducing cell viability, inducing apoptosis, modulating miR21 and miR34a expression, and regulating PTEN, BCL2, TP53, and CDK4 expression. Our findings reveal novel molecular targets and pathways for hypericin action on breast cancer cells and suggest that hypericin may be a promising therapeutic agent for breast cancer treatment.

As a multifunctional signaling molecule, melatonin (ML) is widely considered to induce the defense mechanism and increase the accumulation of secondary metabolites under abiotic stresses. Here, the effects of different concentrations of ML (100 and 200 µM) on the biochemical and molecular responses of Withania coagulans L. in hydroponic conditions under 200 mM NaCl treatment were evaluated. The results showed that NaCl treatment impaired photosynthetic function and reduced plant growth by decreasing photosynthetic pigments and gas exchange parameters. NaCl stress also induced oxidative stress and membrane lipid damage, disrupting Na⁺/K⁺ homeostasis and increasing hydrogen peroxide levels. NaCl toxicity decreased nitrogen (N) assimilation activity in leaves by reducing the activity of enzymes associated with N metabolism. However, adding ML to NaCl-stressed plants improved gas exchange parameters and increased photosynthesis efficiency, resulting in improved plant growth. By enhancing the activity of antioxidant enzymes and reducing hydrogen peroxide levels, ML ameliorated NaCl-induced oxidative stress. By improving N metabolism and restoring Na⁺/K⁺ homeostasis in NaCl-stressed plants, ML improved N uptake and plant adaptation to salinity. ML increased the expression of genes responsible for the biosynthesis of withanolides (FPPS, SQS, HMGR, DXS, DXR, and CYP51G1) and, as a result, increased the accumulation of withanolides A and withaferin A in leaves under NaCl stress. Overall, our results indicate the potential of ML to improve plant adaptation under NaCl stress through fundamental changes in plant metabolism.

There is an increasing interest in the use of nano-fertilizer as an alternative to traditional fertilizers, in order to increase the secondary metabolites in medicinal plants. The present study was conducted to observe the changes in morphological and biochemical properties of three populations of Colchicum speciosum L., from Iran (Filband, Sangdarka, and Kelerd), upon conventional (1.1 and 2.2 mg L-1) and nano-N (1.5 and 3 mg L-1) fertilizers based on completely randomized design (CRD). The anthocyanin and phenolic contents of leaves and corms were determined with a spectrophotometer and corm colchicine was extracted by high-performance liquid chromatography (HPLC). The results represented different responses of morphological and biochemical attributes to populations due to their different origins. Filband with higher altitude showed increased leaf area, plant length, corn weight and diameter when treated with N fertilizers. Increased total phenolic component (TPC) in leaves and corm and also leaf total flavonoids component (TFC) were reported in Filband upon N fertilizers. All fertilizers led to decreased leaf anthocyanin when N fertilizers were applied. A noticeable increase in colchicine was obtained in Kelerd and Sangdarka when plants were treated with 1.5 mg L-1 nano-N fertilizer. Heat map analysis of corm anthocyanin, leaf anthocyanin, leaf TPC, leaf TPC, and colchicine amount showed higher variability under the treatments. According to principal component analysis (PCA), corm TPC, leaf TFC, corm TFC, leaf area, and corm weight were specific traits of Kelerd. In conclusion, different responses of morphological and biochemical traits were reported between populations, and N fertilizers exerted diverse effects on these traits. The population from higher altitudes showed higher phenolic content and lower anthocyanin accumulation under conventional and nano-N fertilizers.