Potential of Plant-Based Extracts to Alleviate Sorbitol-Induced Osmotic Stress in Cabbage Seedlings.

In light of expected climate change, it is important to seek nature-based solutions that can contribute to the protection of our planet as well as to help overcome the emerging adverse changes. In an agricultural context, increasing plant resistance to abiotic stress seems to be crucial. Therefore, the scope of the presented research was focused on the application of botanical extracts that exerted positive effects on model plants growing under controlled laboratory conditions, as well as plants subjected to sorbitol-induced osmotic stress. Foliar spraying increased the length and fresh mass of the shoots (e.g., extracts from Taraxacum officinale, Trifolium pratense, and Pisum sativum) and the roots (e.g., Solidago gigantea, Hypericum perforatum, and Pisum sativum) of cabbage seedlings grown under stressful conditions, as well as their content of photosynthetic pigments (Pisum sativum, Lens culinaris, and Hypericum perforatum) along with total phenolic compounds (Hypericum perforatum, Taraxacum officinale, and Urtica dioica). The antioxidant activity of the shoots measured with the use of DDPH (Pisum sativum, Taraxacum officinale, Urtica dioica, and Hypericum perforatum), ABTS (Trifolium pratense, Symphytum officinale, Valeriana officinalis, Pisum sativum, and Lens culinaris), and FRAP (Symphytum officinale, Valeriana officinalis, Urtica dioica, Hypericum perforatum, and Taraxacum officinale) assays was also enhanced in plants exposed to osmotic stress. Based on these findings, the most promising formulation based on Symphytum officinale was selected and subjected to transcriptomic analysis. The modification of the expression of the following genes was noted: Bol029651 (glutathione S-transferase), Bol027348 (chlorophyll A-B binding protein), Bol015841 (S-adenosylmethionine-dependent methyltransferases), Bol009860 (chlorophyll A-B binding protein), Bol022819 (GDSL lipase/esterase), Bol036512 (heat shock protein 70 family), Bol005916 (DnaJ Chaperone), Bol028754 (pre-mRNA splicing Prp18-interacting factor), Bol009568 (heat shock protein Hsp90 family), Bol039362 (gibberellin regulated protein), Bol007693 (B-box-type zinc finger), Bol034610 (RmlC-like cupin domain superfamily), Bol019811 (myb_SHAQKYF: myb-like DNA-binding domain, SHAQKYF class), Bol028965 (DA1-like Protein). Gene Ontology functional analysis indicated that the application of the extract led to a decrease in the expression of many genes related to the response to stress and photosynthetic systems, which may confirm a reduction in the level of oxidative stress in plants treated with biostimulants. The conducted studies showed that the use of innovative plant-based products exerted positive effects on crops and can be used to supplement current cultivation practices.

Bioactive Compounds from Plant Origin as Natural Antimicrobial Agents for the Treatment of Wound Infections.

The rising prevalence of drug-resistant bacteria underscores the need to search for innovative and nature-based solutions. One of the approaches may be the use of plants that constitute a rich source of miscellaneous compounds with a wide range of biological properties. This review explores the antimicrobial activity of seven bioactives and their possible molecular mechanisms of action. Special attention was focused on the antibacterial properties of berberine, catechin, chelerythrine, cinnamaldehyde, ellagic acid, proanthocyanidin, and sanguinarine against Staphylococcus aureus, Enterococcus spp., Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, Serratia marcescens and Pseudomonas aeruginosa. The growing interest in novel therapeutic strategies based on new plant-derived formulations was confirmed by the growing number of articles. Natural products are one of the most promising and intensively examined agents to combat the consequences of the overuse and misuse of classical antibiotics.

Silicone Oil-Based Nanoadjuvants as Candidates for a New Formulation of Intranasal Vaccines.

Many conventional vaccines are administered via a needle injection, while most pathogens primarily invade the host via mucosal surfaces. Moreover, protective IgA antibodies are insufficiently induced by parenteral vaccines. Mucosal immunity induces both local and systemic response to pathogens and typically lasts for long periods of time. Therefore, vaccination via mucosal routes has been increasingly explored. However, mucosal vaccines require potent adjuvants to become efficacious. Despite many efforts to develop safe and robust adjuvants for mucosal vaccines, only a few have been approved for use in human formulations. The aim of our study was to design, develop and characterize new silicone oil-based nanoadjuvant candidates for intranasal vaccines with potential to become mucosal adjuvants. We have developed an array of nanoadjuvant candidates (NACs), based on well-defined ingredients. NAC1, 2 and 3 are based on silicone oil, but differ in the used detergents and organic solvents, which results in variations in their droplet size and zeta potential. NACs' cytotoxicity, Tumor Necrosis Factor α (TNF-α) induction and their effect on antigen engulfment by immune cells were tested in vitro. Adjuvant properties of NACs were verified by intranasal vaccination of mice together with ovalbumin (OVA). NACs show remarkable stability and do not require any special storage conditions. They exhibit bio-adhesiveness and influence the degree of model protein engulfment by epithelial cells. Moreover, they induce high specific anti-OVA IgG antibody titers after two intranasal administrations. Nanoadjuvant candidates composed of silicone oil and cationic detergents are stable, exhibit remarkable adjuvant properties and can be used as adjuvants for intranasal immunization.