Innovative utilization of harvested mushroom substrate for green synthesis of silver nanoparticles: A multi-response optimization approach

In this work, harvested mushroom substrate (HMS) has been explored for the first time through a comprehensive optimization study for the green synthesis of silver nanoparticles (AgNPs). A multiple response central composite design with three parameters: pH of the reaction mixture, temperature, and incubation period at three distinct levels was employed in the optimization study. The particle size of AgNPs, UV absorbance, and the percentage of Ag/Cl elemental ratio were considered as the response parameters. For each response variable examined the model used was found to be significant (P < 0.05). The ideal conditions were: pH 8.9, a temperature of 59.4 °C, and an incubation period of 48.5 h. The UV-visible spectra of AgNPs indicated that the absorption maxima for AgNP-3 were 414 nm, 420 for AgNPs-2, and 457 for AgNPs-1. The XRD analysis of AgNPs-3 and AgNPs-2 show a large diffraction peak at ∼38.2°, ∼44.2°, ∼64.4°, and ∼77.4°, respectively, which relate to the planes of polycrystalline face-centered cubic (fcc) silver. Additionally, the XRD result of AgNPs-1, reveals diffraction characteristics of AgCl planes (111, 200, 220, 311, 222, and 400). The TEM investigations indicated that the smallest particles were synthesized at pH 9 with average diameters of 35 ± 6 nm (AgNPs-3). The zeta potentials of the AgNPs are -36 (AgNPs-3), -28 (AgNPs-2), and -19 (AgNPs-1) mV, respectively. The distinct IR peak at 3400, 1634, and 1383 cm-1 indicated the typical vibration of phenols, proteins, and alkaloids, respectively. The AgNPs were further evaluated against gram (+) strain Bacillus subtilis (MTCC 736) and gram (-) strain Escherichia coli (MTCC 68). All of the NPs tested positive for antibacterial activity against both bacterial strains. The study makes a sustainable alternative to disposing of HMS to achieve the Sustainable Development Goals (SDGs).

Anticancer activity and other biomedical properties of β-sitosterol: Bridging phytochemistry and current pharmacological evidence for future translational approaches

Sterols, including β-sitosterol, are essential components of cellular membranes in both plant and animal cells. Despite being a major phytosterol in various plant materials, comprehensive scientific knowledge regarding the properties of β-sitosterol and its potential applications is essential for scholarly pursuits and utilization purposes. β-sitosterol shares similar chemical characteristics with cholesterol and exhibits several pharmacological activities without major toxicity. This study aims to bridge the gap between phytochemistry and current pharmacological evidence of β-sitosterol, focusing on its anticancer activity and other biomedical properties. The goal is to provide a comprehensive understanding of β-sitosterol's potential for future translational approaches. A thorough examination of the literature was conducted to gather relevant information on the biological properties of β-sitosterol, particularly its anticancer therapeutic potential. Various databases were searched, including PubMed/MedLine, Scopus, Google Scholar, and Web of Science using appropriate keywords. Studies investigating the effects of β-sitosterol on different types of cancer were analyzed, focusing on mechanisms of action, pharmacological screening, and chemosensitizing properties. Modern pharmacological screening studies have revealed the potential anticancer therapeutic properties of β-sitosterol against various types of cancer, including leukemia, lung, stomach, breast, colon, ovarian, and prostate cancer. β-sitosterol has demonstrated chemosensitizing effects on cancer cells, interfering with multiple cell signaling pathways involved in proliferation, cell cycle arrest, apoptosis, survival, metastasis invasion, angiogenesis, and inflammation. Structural derivatives of β-sitosterol have also shown anti-cancer effects. However, research in the field of drug delivery and the detailed mode of action of β-sitosterol-mediated anticancer activities remains limited. β-sitosterol, as a non-toxic compound with significant pharmacological potential, exhibits promising anticancer effects against various cancer types. Despite being relatively less potent than conventional cancer chemotherapeutics, β-sitosterol holds potential as a safe and effective nutraceutical against cancer. Further comprehensive studies are recommended to explore the biological properties of β-sitosterol, including its mode of action, and develop novel formulations for its potential use in cancer treatment. This review provides a foundation for future investigations and highlights the need for further research on β-sitosterol as a potent superfood in combating cancer.

Antioxidative and Antibacterial Hydro-Ethanolic Fraction from an Asian Edible Mushroom Lentinus sajor-caju (Agaricomycetes) Suppresses Inflammatory Responses by Downregulating COX-2 and iNOS Expression

Mushrooms are prevalently important sources of pharmaceutically active metabolites. Various mushroom species belonging to the Lentinus genus are recognized for their nutritional and therapeutic properties. One such species is L. sajor-caju, which is renowned in Southeast Asian nations for its culinary value. The primary goal of this study is to investigate the potential medicinal properties of L. sajor-caju, specifically its antioxidant, antibacterial, and anti-inflammatory effects. A hydroethanolic extract was formulated using dried basidiocarps, which exhibited a high phenolic content of approximately 14% and a flavonoid content of approximately 2.7%. The extract demonstrated significant antioxidant potential in in vitro reactions. The extract is sufficiently capable of scavenging free radicals (DPPH and ABTS) and chelate Fe2+ with EC50 values spanning from 186 to 390 μg/mL. In addition, considerable antimicrobial activity against tested pathogenic microorganisms was observed, as indicated by low MIC50 values (256-358 μg/mL). Moreover, the fraction was found to prevent heat-induced protein denaturation which signifies its anti-inflammatory potential. When tested on the RAW 264.7 cell line, reduction in the nitrite production, and downregulation of COX-2 and iNOS mRNA expression was observed which are the key regulator of inflammatory signalling systems. The study, therefore, recommends the use of L. sajor-caju in the medical and pharmaceutical industries for the benefit of humanity.