Hamid Reza Eisvand

Allium jesdianum, an endangered medicinal plant endemic to Iran, exhibits notable pharmacological properties, including antioxidant and antibacterial effects. This study explored the influence of solvent polarity on the extraction efficiency of phytochemicals and their associated bioactivities in wild populations of A. jesdianum collected from six natural habitats (P1–P6). Aerial parts of the plant were extracted using methanol, followed by fractionation with ethyl acetate and n-hexane. Total phenolic and flavonoid contents were quantified via Folin–Ciocalteu and aluminum chloride methods. Antioxidant activity was assessed using DPPH and FRAP assays, while antibacterial potential was evaluated against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using MIC and MBC assays. Despite its acknowledged medicinal significance, the variation in phytochemical composition and bioactivities of A. jesdianum at the population level has been largely overlooked. To fill this gap in knowledge, the current study offers the inaugural systematic and comparative assessment of various wild populations from six different natural environments, incorporating the influences of population origin and solvent polarity on the bioactive potential of the plant. The results showed that both solvent type and population origin significantly influenced phytochemical content and biological activity. Ethyl acetate and n-hexane fractions from the P5 and P6 populations yielded the highest levels of phenolics (70.37 mg GAE g−1) and flavonoids (234.75 mg Rutin g−1), along with the strongest antioxidant and antibacterial effects (IC₅₀ = 0.034 mg mL−1; MIC = 2 mg mL−1 against S. aureus). HPLC analysis identified ferulic acid and rutin as predominant bioactive compounds, whose accumulation correlated strongly with soil macronutrients (N, P, K), rather than altitude. Heat map and PCA analyses revealed pronounced phytochemical diversity among the wild populations, with P6 showing superior metabolite profiles. The high bioactive properties of populations P5 and P6 suggest their suitability for targeted conservation, selective cultivation, and use in pharmaceutical or nutraceutical products, offering valuable advice for population-specific approaches to preserve and capitalise on the medicinal value of A. jesdianum.

Water scarcity is a global challenge with profound implications, particularly for agriculture, where it undermines crop production by diminishing yields and heightening vulnerability to environmental stresses. This study investigates the impact of Bacillin 20, a derivative of Bacillus thuringiensis , on soybean plant physiology under drought stress, focusing on growth dynamics, photosynthetic activity, and nutrient assimilation. The experimentation was carried out using a factorial structure within a completely randomized design and four replications. Factors included drought levels (control, −0.75 MPa and −1.5 MPa) and Bacillin 20 concentrations (0, 10 ⁻¹¹ M and 10 ⁻⁹ M). Results indicated that drought stress significantly reduced plant height, leaf area, shoot dry weight, photosynthetic rate, stomatal conductance, transpiration, substomatal CO ₂ concentration, nodulation, and root length and volume. Bacillin 20 application had mixed effects, with no significant impact on plant height but increasing leaf area, enhancing shoot dry weight under moderate drought, and improving photosynthetic rate. The interaction between drought and Bacillin 20 was significant, particularly in terms of shoot dry weight and photosynthetic rate. Additionally, Bacillin 20 at 10 ⁻¹¹ M increased root tips by 12.6% and shoot dry weight by 28%; it increased nodule number by 51% only under normal moisture conditions, and decreased it under drought stress. Drought increased leaf N, Mg, Zn, Fe, Mn, and B contents, while Bacillin raised leaf N at −0.75 MPa and decreased Zn and Mn under severe drought (−1.5 MPa). The increased plant N and decreased nodulation under drought suggest enhanced nodule efficiency. Bacillin 20 did not affect P, K, Ca, and S contents, which were influenced solely by drought.

Caffeic acid, one of the important phenolic compounds in plants, plays a significant role in enhancing the defense mechanisms and adaptation of plants to environmental stresses, including drought. This study aimed to investigate the effect of drought stress on the expression of genes involved in the biosynthesis of caffeic acid, photosynthetic mechanisms, and antioxidant enzyme activity in three cultivars of beans. The experiment was conducted in a split-plot design within a randomized complete block design, with three irrigation levels (50, 75, and 100% of water requirement) as the main factor and three bean cultivars (red, white, and pinto) as the sub-factor, with three replications. The results showed that drought stress increased the expression of caffeic acid biosynthesis genes and enhanced antioxidant enzyme activities (CAT, SOD, POD) in all bean cultivars. These responses were particularly stronger in pinto and red beans. For instance, caffeic acid content increased by more than 60% under severe drought in pinto bean tissues, contributing to improved antioxidant capacity. While drought stress reduced seed yield in all cultivars, the decline was less pronounced in pinto bean (about 14%), indicating its higher drought tolerance compared to the white bean, which showed a larger yield reduction. These results suggest that the increased expression of genes involved in caffeic acid biosynthesis and the enhancement of antioxidant activity are key mechanisms in plant adaptation to drought. Identifying and utilizing these mechanisms can provide effective strategies for genetic improvement and the production of drought-resistant cultivars. Moreover, the findings can contribute to optimizing irrigation management and improving production sustainability in arid and semi-arid regions.

Carbon monoxide (CO) is recognized as a signaling molecule in plants, inducing various physiological responses. This article briefly examines the physiological functions of CO in seed biology and seedlings’ responses to environmental stresses. The activity of heme oxygenase (HO), the main enzyme responsible for CO synthesis, is a key factor controlling CO levels in plant cells. CO can influence seed germination by regulating seed dormancy through interactions with genes and hormones. Additionally, CO positively affects seedling growth by enhancing the antioxidant system, thereby increasing resistance to oxidative damage caused by stress. CO has beneficial effects on root development, root length, stomatal closure, and regulation of the photosynthetic system. Its interaction with reactive oxygen species (ROS) mediates hormone- and light-dependent growth processes during the early stages of plant development under stress. Furthermore, CO interacts with other signaling molecules, such as nitric oxide (NO), molecular hydrogen (H₂), and hydrogen sulfide (H₂S). By gaining a better understanding of the molecular mechanisms underlying these processes, CO can be more effectively utilized to improve seed germination and seedling growth in agricultural practices.