Chia (Salvia hispanica L.) Seeds Contain a Highly Stable Trypsin Inhibitor with Potential for Bacterial Management Alone or in Drug Combination Therapy with Oxacillin

Antifungal activity of a trypsin inhibitor from Salvia hispanica L. (chia) seeds against fluconazole-resistant strains of Candida spp. and evaluation of its toxicity in vitro

The incidence of Candida species resistant to traditional antifungal drugs is increasing globally. This issue significantly impacts patients' lives and increases healthcare expenses, confirming the need to develop novel therapeutic strategies. Recently, a thermostable trypsin inhibitor named ShTI (11.558 kDa), which has antibacterial effects on Staphylococcus aureus, was isolated from Salvia hispanica L. (chia) seeds. This study aimed to assess the antifungal effect of ShTI against Candida species and its synergism with fluconazole and to evaluate its mode of action. Preliminary toxicological studies on mouse fibroblasts were also performed. ShTI exhibited antifungal effects against C. parapsilosis (ATCC® 22,019), C. krusei (ATCC® 6258), and six clinical fluconazole-resistant strains of C. albicans (2), C. parapsilosis (2), and C. tropicalis (2). The minimum inhibitory concentration (MIC) values were 4.1 µM (inhibiting 50% of the isolates) and 8.2 µM (inhibiting 100% of the isolates). Additionally, when combined with fluconazole, ShTI had a synergistic effect on C. albicans, altering the morphological structure of the yeast. The mode of action of ShTI against C. krusei (ATCC® 6258) and C. albicans involves cell membrane permeabilization, the overproduction of reactive oxygen species, the formation of pseudohyphae, pore formation, and consequently, cell death. In addition, ShTI (8.65 and 17.3 µM) had noncytotoxic and nongenotoxic effects on L929 mouse fibroblasts. These findings suggest that ShTI could be a promising antimicrobial candidate, but further research is necessary to advance its application as a novel antifungal agent.

Plant Protease Inhibitors as Emerging Antimicrobial Peptide Agents: A Comprehensive Review

Antimicrobial peptides (AMPs) are important mediator molecules of the innate defense mechanisms in a wide range of living organisms, including bacteria, mammals, and plants. Among them, peptide protease inhibitors (PPIs) from plants play a central role in their defense mechanisms by directly attacking pathogens or by modulating the plant's defense response. The growing prevalence of microbial resistance to currently available antibiotics has intensified the interest concerning these molecules as novel antimicrobial agents. In this scenario, PPIs isolated from a variety of plants have shown potential in inhibiting the growth of pathogenic bacteria, protozoans, and fungal strains, either by interfering with essential biochemical or physiological processes or by altering the permeability of biological membranes of invading organisms. Moreover, these molecules are active inhibitors of a range of proteases, including aspartic, serine, and cysteine types, with some showing particular efficacy as trypsin and chymotrypsin inhibitors. In this review, we provide a comprehensive analysis of the potential of plant-derived PPIs as novel antimicrobial molecules, highlighting their broad-spectrum antimicrobial efficacy, specificity, and minimal toxicity. These natural compounds exhibit diverse mechanisms of action and often multifunctionality, positioning them as promising molecular scaffolds for developing new therapeutic antibacterial agents.

Nutritional and Functional New Perspectives and Potential Health Benefits of Quinoa and Chia Seeds

Quinoa (Chenopodium quinoa Willd) and chia (Salvia hispanica) are essential traditional crops with excellent nutritional properties. Quinoa is known for its high and good quality protein content and nine essential amino acids vital for an individual's development and growth, whereas chia seeds contain high dietary fiber content, calories, lipids, minerals (calcium, magnesium, iron, phosphorus, and zinc), and vitamins (A and B complex). Chia seeds are also known for their presence of a high amount of omega-3 fatty acids. Both quinoa and chia seeds are gluten-free and provide medicinal properties due to bioactive compounds, which help combat various chronic diseases such as diabetes, obesity, cardiovascular diseases, and metabolic diseases such as cancer. Quinoa seeds possess phenolic compounds, particularly kaempferol, which can help prevent cancer. Many food products can be developed by fortifying quinoa and chia seeds in different concentrations to enhance their nutritional profile, such as extruded snacks, meat products, etc. Furthermore, it highlights the value-added products that can be developed by including quinoa and chia seeds, alone and in combination. This review focused on the recent development in quinoa and chia seeds nutritional, bioactive properties, and processing for potential human health and therapeutic applications.