Green synthesis of silver nanoparticles using Rhodiola imbricata and Withania somnifera root extract and their potential catalytic, antioxidant, cytotoxic and growth-promoting activities

Biological potential of Argyrolobium roseum (Camb.) Jaub & Spach mediated silver nanoparticles and their effect on the growth of wheat seeds

The green synthesis of silver nanoparticles (AgNPs) using plant-based derivatives is getting attention for biological applications because of their small dimensions and shape. In this study, AgNPs were prepared using leaf extract of Argyrolobium roseum (A. roseum) (Camb.) Jaub. & Spach. and then characterized via Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet-visible absorption (UV-Vis) spectroscopy. The UV-visible spectrum displayed a absorption peak at 450 nm and x-ray diffraction depicted a crystalline nature of biogenic NPs. FTIR analysis showed various functional groups involved in the reduction and capping of AgNPs while SEM revealed the spherical form of synthesized AgNPs. The antibacterial assay was conducted using disc diffusion assay and highest inhibition zones were recorded against Bacillus subtilis (B. subtilis) (9.6 ± 0.5 mm) and Staphylococcus aureus (S. aureus) (8.6 ± 0.5 mm). The antioxidant potential was assessed via DPPH scavenging assay and highest percentage inhibition (89%) was observed at 100 μg/mL. Subsequently, different concentrations of A. roseum AgNPs were applied on the wheat seedlings to investigate its effects on different growth parameters. After applying AgNPs, significant increase in the fresh weight (FW), dry weight (DW), root length (RL), shoot length (SL), leaf number (LN) and chlorophyll content (CC) in wheat (Akbar-2019 variety) seedlings was observed in comparison to the control seedlings. Overall, A. roseum mediated synthesis of AgNPs was cost-effective and safe and can be used in agriculture, biomedical and other fields. RESEARCH HIGHLIGHTS: Synthesis and characterization of A. roseum AgNPs was done. Biogenic AgNPs revealed potent antibacterial and antioxidant potential. A. roseum mediated AgNPs also increases the growth and germination of wheat seedlings.

Rhodiola rosea: a review in the context of PPPM approach

A natural "medicine and food" plant, Rhodiola rosea (RR) is primarily made up of organic acids, phenolic compounds, sterols, glycosides, vitamins, lipids, proteins, amino acids, trace elements, and other physiologically active substances. In vitro, non-clinical and clinical studies confirmed that it exerts anti-inflammatory, antioxidant, and immune regulatory effects, balances the gut microbiota, and alleviates vascular circulatory disorders. RR can prolong life and has great application potential in preventing and treating suboptimal health, non-communicable diseases, and COVID-19. This narrative review discusses the effects of RR in preventing organ damage (such as the liver, lung, heart, brain, kidneys, intestines, and blood vessels) in non-communicable diseases from the perspective of predictive, preventive, and personalised medicine (PPPM/3PM). In conclusion, as an adaptogen, RR can provide personalised health strategies to improve the quality of life and overall health status.

Electrospun polyvinyl alcohol/Withania somnifera extract nanofibers incorporating tadalafil-loaded nanoparticles for diabetic ulcers

Background: Impaired inflammation and vascularization are common reasons for delayed diabetic wound healing. Nanoparticles (NPs)-in-nanofibers composites can manage diabetic wounds. A multifunctional scaffold was developed based on tadalafil (TDF)-loaded NPs incorporated into polyvinyl alcohol/Withania somnifera extract nanofibers. Materials & methods: TDF-loaded NPs were prepared and fully characterized in terms of their physicochemical properties. Extract of ashwagandha was prepared and a blend composed of TDF-loaded NPs, herbal extract and polyvinyl alcohol was used to prepare the whole composite. Results: The whole composite exhibited improved wound closure in a diabetic rat model in terms of reduced inflammation and enhanced angiogenesis. Conclusion: Results suggest that this multifunctional composite could serve as a promising diabetic wound dressing.

Stable biogenic silver nanoparticles from Syzygium nervosum bud extract for enhanced catalytic, antibacterial and antifungal properties

In the present study, the biosynthesis of stable silver nanoparticles (BioAgNPs) was accomplished successfully for the first time by using an aqueous extract derived from the buds of Syzygium nervosum (SN) as both a reducing and a stabilizing agent. Transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HR-TEM) investigations revealed that the biosynthesized BioAgNPs were predominantly spherical with an average size of 10-30 nm. It was found that the outstanding stability of the BioAgNPs colloidal solution was assigned to the additive effect of the surrounding protective organic layer and the highly negatively charged surface of the nanoparticles. Consequently, good antibacterial activity was demonstrated by the colloidal BioAgNPs solution against four distinct bacterial strains, including Gram-positive S. aureus and B. subtilis as well as Gram-negative E. coli and S. typhi. Interestingly, the biosynthesized BioAgNPs displayed greater antibacterial activity even when tested at low doses against Gram-negative S. typhi. In addition, the biogenic AgNPs demonstrated a significant level of catalytic activity in the process of converting 2-NP, 3-NP, and 4-NP into aminophenols within 15 min, with reaction rate constants of 9.0 × 10-4, 10 × 10-4, and 9.0 × 10-4 s-1, respectively. BioAgNPs formulations were assessed against anthracnose disease in tea plants and were found to be as effective as the positive control at a dose of 20-fold dilution, but less effective at a dose of 30-fold dilution. Both doses of BioAgNPs formulations significantly suppressed Colletotrichum camelliae (anthracnose disease) without affecting the growth of the tea plants.

Antifungal Activity of Juglans-regia-Mediated Silver Nanoparticles (AgNPs) against Aspergillus-ochraceus-Induced Toxicity in In Vitro and In Vivo Settings

Aflatoxins produced by some species of Aspergillus are considered secondary toxic fungal by-products in feeds and food. Over the past few decades, many experts have focused on preventing the production of aflatoxins by Aspergillus ochraceus and also reducing its toxicity. Applications of various nanomaterials in preventing the production of these toxic aflatoxins have received a lot of attention recently. The purpose of this study was to ascertain the protective impact of Juglans-regia-mediated silver nanoparticles (AgNPs) against Aspergillus-ochraceus-induced toxicity by exhibiting strong antifungal activity in in vitro (wheat seeds) and in vivo (Albino rats) settings. For the synthesis of AgNPs, the leaf extract of J. regia enriched with high phenolic (72.68 ± 2.13 mg GAE/g DW) and flavonoid (18.89 ± 0.31 mg QE/g DW) contents was used. Synthesized AgNPs were characterized by various techniques, including TEM, EDX, FT-IR, and XRD, which revealed that the particles were spherical in shape with no agglomeration and fine particle size in the range of 16-20 nm. In vitro antifungal activity of AgNPs was tested on wheat grains by inhibiting the production of toxic aflatoxins by A. ochraceus. According to the results obtained from High-Performance Liquid Chromatography (HPLC) and Thin-Layer Chromatography (TLC) analyses, there was a correlation between the concentration of AgNPs and a decrease in the production of aflatoxin G1, B1, and G2. For in vivo antifungal activity, Albino rats were administrated with different doses of AgNPs in five groups. The results indicated that the feed concentration of 50 µg/kg feed of AgNPs was more effective in improving the disturbed levels of different functional parameters of the liver (alanine transaminase (ALT): 54.0 ± 3.79 U/L and aspartate transaminase (AST): 206 ± 8.69 U/L) and kidney (creatinine 0.49 ± 0.020 U/L and BUN 35.7 ± 1.45 U/L), as well as the lipid profile (LDL 22.3 ± 1.45 U/L and HDL 26.3 ± 2.33 U/L). Furthermore, the histopathological analysis of various organs also revealed that the production of aflatoxins was successfully inhibited by AgNPs. It was concluded that the harmful effects of aflatoxins produced by A. ochraceus can be successfully neutralized by using J. regia-mediated AgNPs.

Sedeveria pink ruby Extract-Mediated Synthesis of Gold and Silver Nanoparticles and Their Bioactivity against Livestock Pathogens and in Different Cell Lines

Biological synthesis of metal nanoparticles has a significant impact in developing sustainable technologies for human, animal, and environmental safety. In this study, we synthesized gold and silver nanoparticles (NPs) using Sedeveria pink ruby (SP) extract and characterized them using UV–visible spectrophotometry, FESEM-EDX, HR-TEM, XRD, and FT-IR spectroscopy. Furthermore, antimicrobial and antioxidant activities and cytotoxicity of the synthesized NPs were evaluated. UV–visible absorption spectra showed λmax at 531 and 410 nm, corresponding to the presence of SP gold NPs (SP-AuNPs) and SP silver NPs (SP-AgNPs). Most NPs were spherical and a few were triangular rods, measuring 5–30 and 10–40 nm, respectively. EDX elemental composition analysis revealed that SP-AuNPs and SP-AgNPs accounted for >60% and 30% of NPs, respectively. Additionally, some organic moieties were present, likely derived from various metabolites in the natural plant extract, which acted as stabilizing and reducing agents. Next, the antimicrobial activity of the NPs against pathogenic microbes was tested. SP-AgNPs showed potent antibacterial activity against Escherichia coli and Yersinia pseudotuberculosis. Moreover, at moderate and low concentrations, both NPs exhibited weak cytotoxicity in chicken fibroblasts (DF-1) and macrophages (HD11) as well as human intestinal cancer cells (HT-29). Meanwhile, at high concentrations, the NPs exhibited strong cytotoxicity in both chicken and human cell lines. Therefore, the synthesized SP-AuNPs and SP-AgNPs may act as promising materials to treat poultry diseases.

Implication of Nanoparticles to Combat Chronic Liver and Kidney Diseases: Progress and Perspectives

Liver and kidney diseases are the most frequently encountered problems around the globe. Damage to the liver and kidney may occur as a result of exposure to various drugs, chemicals, toxins, and pathogens, leading to severe disease conditions such as cirrhosis, fibrosis, hepatitis, acute kidney injury, and liver and renal failure. In this regard, the use of nanoparticles (NPs) such as silver nanoparticles (AgNPs), gold nanoparticles (AuNPs), and zinc oxide nanoparticles (ZnONPs) has emerged as a rapidly developing field of study in terms of safe delivery of various medications to target organs with minimal side effects. Due to their physical characteristics, NPs have inherent pharmacological effects, and an accidental buildup can have a significant impact on the structure and function of the liver and kidney. By suppressing the expression of the proinflammatory cytokines iNOS and COX-2, NPs are known to possess anti-inflammatory effects. Additionally, NPs have demonstrated their ability to operate as an antioxidant, squelching the generation of ROS caused by substances that cause oxidative stress. Finally, because of their pro-oxidant properties, they are also known to increase the level of ROS, which causes malignant liver and kidney cells to undergo apoptosis. As a result, NPs can be regarded as a double-edged sword whose inherent therapeutic benefits can be refined as we work to comprehend them in terms of their toxicity.

Withania somnifera: Progress towards a Pharmaceutical Agent for Immunomodulation and Cancer Therapeutics

Chemotherapy is one of the prime treatment options for cancer. However, the key issues with traditional chemotherapy are recurrence of cancer, development of resistance to chemotherapeutic agents, affordability, late-stage detection, serious health consequences, and inaccessibility. Hence, there is an urgent need to find innovative and cost-effective therapies that can target multiple gene products with minimal adverse reactions. Natural phytochemicals originating from plants constitute a significant proportion of the possible therapeutic agents. In this article, we reviewed the advances and the potential of Withania somnifera (WS) as an anticancer and immunomodulatory molecule. Several preclinical studies have shown the potential of WS to prevent or slow the progression of cancer originating from various organs such as the liver, cervix, breast, brain, colon, skin, lung, and prostate. WS extracts act via various pathways and provide optimum effectiveness against drug resistance in cancer. However, stability, bioavailability, and target specificity are major obstacles in combination therapy and have limited their application. The novel nanotechnology approaches enable solubility, stability, absorption, protection from premature degradation in the body, and increased circulation time and invariably results in a high differential uptake efficiency in the phytochemical’s target cells. The present review primarily emphasizes the insights of WS source, chemistry, and the molecular pathways involved in tumor regression, as well as developments achieved in the delivery of WS for cancer therapy using nanotechnology. This review substantiates WS as a potential immunomodulatory, anticancer, and chemopreventive agent and highlights its potential use in cancer treatment.