Antimicrobial, antioxidant and anticancer activities of gold nanoparticles green synthesized using Mangifera indica seed aqueous extract

Comprehensive Review on Fruit Seeds: Nutritional, Phytochemical, Nanotechnology, Toxicity, Food Biochemistry, and Biotechnology Perspective

Fruit seeds are leftovers from a variety of culinary sectors. They are generally unutilized and contribute greatly to global disposals. These seeds not only possess various nutritional attributes but also have many heath-beneficial properties. One way to make use of these seeds is to extract their bioactive components and create fortified food items. Nowadays, researchers are highly interested in creating innovative functional meals and food components from these unconventional resources. The main objective of this manuscript was to determine the usefulness of seed powder from 70 highly consumed fruits, including Apple, Apricot, Avocado, Banana, Blackberry, Blackcurrant, Blueberry, Cherry, Common plum, Cranberry, Gooseberry, Jackfruit, Jamun, Kiwi, Lemon, Mahua, Mango, Melon, Olive, Orange, and many more have been presented. The nutritional attributes, phytochemical composition, health advantages, nanotechnology applications, and toxicity of these fruit seeds have been fully depicted. This study also goes into in-depth detailing on creating useful food items out of these seeds, such as bakery goods, milk products, cereal-based goods, and meat products. It also identifies enzymes purified from these seeds along with their biochemical applications and any research openings in this area.

Induction of autophagy-dependent and caspase- and microtubule-acetylation-independent cell death by phytochemical-stabilized gold nanopolygons in colorectal adenocarcinoma cells

Collective functionalization of the phytochemicals of medicinal herbs on nanoparticles is emerging as a potential cancer therapeutic strategy. This study presents the facile synthesis of surface-functionalized gold nanoparticles using Bacopa monnieri (Brahmi; Bm) phytochemicals and their therapeutically relevant mechanism of action in the colorectal cancer cell line, HT29. The nanoparticles were characterized using UV-visible spectroscopy, TEM-EDAX, zeta potential analysis, TGA, FTIR and 1H NMR spectroscopy, and HR-LC-MS. The particles (Bm-GNPs) were of polygonal shape and were stable against aggregation. They entered the target cells and inhibited the viability and clonogenicity of the cells with eight times more antiproliferative efficacy (25 ± 1.5 μg mL-1) than Bm extract (Bm-EX). In vitro studies revealed that Bm-GNPs bind tubulin (a protein crucial in cell division and a target of anticancer drugs) and disrupt its helical structure without grossly altering its tertiary conformation. Like other antitubulin agents, Bm-GNPs induced G2/M arrest and ultimately killed the cells, as confirmed using flow cytometry analyses. ZVAD-FMK-mediated global pan-caspase inhibition and the apparent absence of cleaved caspase-3 in treated cells indicated that the death did not involve the classic apoptosis pathway. Cellular ultrastructure analyses, western immunoblots, and in situ immunofluorescence visualization of cellular microtubules revealed microtubule-acetylation-independent induction of autophagy as the facilitator of cell death. Together, the data indicate strong antiproliferative efficacy and a possible mechanism of action for these designer nanoparticles. Bm-GNPs, therefore, merit further investigations, including preclinical evaluations, for their therapeutic potential as inducers of non-apoptotic cell death.

Valorization of non-edible fruit seeds into valuable products: A sustainable approach towards circular bioeconomy

Global imperatives have recently shown a paradigm shift in the prevailing resource utilization model from a linear approach to a circular bioeconomy. The primary goal of the circular bioeconomy model is to minimize waste by effective re-usage of organic waste and efficient nutrient recycling. In essence, circular bioeconomy integrates the fundamental concept of circular economy, which strives to offer sustainable goods and services by leveraging biological resources and processes. Notably, the circular bioeconomy differs from conventional waste recycling by prioritizing the safeguarding and restoration of production ecosystems, focusing on harnessing renewable biological resources and their associated waste streams to produce value-added products like food, animal feed, and bioenergy. Amidst these sustainability efforts, fruit seeds are getting considerable attention, which were previously overlooked and commonly discarded but were known to comprise diverse chemicals with significant industrial applications, not limited to cosmetics and pharmaceutical industries. While, polyphenols in these seeds offer extensive health benefits, the inadequate conversion of fruit waste into valuable products poses substantial environmental challenges and resource wastage. This review aims to comprehend the known information about the application of non-edible fruit seeds for synthesising metallic nanoparticles, carbon dots, biochar, biosorbent, and biodiesel. Further, this review sheds light on the potential use of these seeds as functional foods and feed ingredients; it also comprehends the safety aspects associated with their utilization. Overall, this review aims to provide a roadmap for harnessing the potential of non-edible fruit seeds by adhering to the principles of a sustainable circular bioeconomy.

Synthesis of green zinc-oxide nanoparticles and its dose-dependent beneficial effect on spermatozoa during preservation: sperm functional integrity, fertility and antimicrobial activity

Introduction: The development of an effective extender is important for semen preservation and the artificial insemination (AI) industry. This study demonstrates the beneficial effect of zinc oxide nanoparticles (ZnO-NPs) as an additive to semen extenders to improve semen quality, fertility, and antibacterial activity during liquid preservation in a boar model. Methods: Initially, to find out the safe concentration of ZnO-NPs in sperm cells, a wide range of ZnO-NP concentrations (0, 5, 10, 50, 100, 500, and 1,000 μM) were co-incubated with sperm at 37°C for a cytotoxic study. These NP concentrations were compared to their salt control zinc acetate (ZA) at the same concentrations and to a control group. The effect of the different concentrations of ZnO-NPs on sperm motility, membrane integrity, mitochondrial membrane potential (MMP), and apoptosis was assessed. Accordingly, the non-toxic dose was selected and supplemented in MODENA extender to determine its beneficial effect on the boar semen parameters mentioned and the lipid peroxidation (LPO) levels during liquid preservation at 16°C for 6 days. The non-cytotoxic dosage was subsequently chosen for AI, fertility investigations, and the evaluation of the antibacterial efficacy of ZnO-NPs during preservation hours. An antibacterial study of ZnO-NPs and its salt control at doses of 10 μM and 50 μM was carried out by the colony forming unit (CFU) method. Results and discussion: The cytotoxic study revealed that 5, 10, and 50 μM of ZnO-NPs are safe. Consequently, semen preserved in the MODENA extender, incorporating the non-toxic dose, exhibited 10 and 50 μM ZnO-NPs as the optimal concentrations for beneficial outcomes during liquid preservation at 16°C. ZnO-NPs of 10 μM concentration resulted in a significantly (p < 0.05) improved conception rate of 86.95% compared to the control of 73.13%. ZnO-NPs of 10 and 50 μM concentrations exhibit potent antimicrobial action by reducing the number of colonies formed with days of preservation in comparison to the negative control. The investigation concluded that the incorporation of 10 μM ZnO-NPs led to enhancements in sperm motility, membrane integrity, and MMP, attributed to a reduction in the malondialdehyde (MDA) levels. This improvement was accompanied by a concurrent increase in fertility rates, including farrowing rate and litter size, during the liquid preservation process. Furthermore, ZnO-NPs exhibited an antimicrobial effect, resulting in decreased bacterial growth while preserving boar semen at 16°C for 6 days. These findings suggest that ZnO-NPs could serve as a viable alternative to antibiotics, potentially mitigating antibiotic resistance concerns within the food chain.

Biosynthesis, Characterization, and Biomedical Applications of Gold Nanoparticles with Cucurbita moschata Duchesne Ex Poiret Peel Aqueous Extracts

In this study, AuNPs were biosynthesized from Cucurbita moschata fruit peel extracts. Biosynthesized AuNPs exhibited maximum absorbance at a 555 nm wavelength, and XRD analysis indicated that the CM-AuNPs had a particle size of less than 100 nm and a cubic crystal structure. TEM scans revealed that the gold particles exhibited a spherical morphology, with an average size of 18.10 nm. FTIR analysis revealed strong peaks indicating the presence of functional groups involved in the reduction reactions. The surface charge of the biosynthesized AuNPs was determined to be -19.7 mV. The antibacterial and antifungal activities of AuNPs against pathogen strains were assessed by the minimum inhibitory concentration (MIC) method. The cytotoxic effects of CM-AuNPs on cancer cell lines (Sk-Ov-3, CaCo2, and A549) and healthy cell lines (HUVEC) were investigated using the MTT method. The findings indicated that AuNPs biosynthesized by the green synthesis method using C. moschata peel aqueous extract had high inhibition on the growth of pathogenic microorganisms and effective cytotoxic activity against cancerous cell lines at low doses. As a result, it can be concluded that CM-AuNPs will be eminently effective in the production of antibacterial and/or anticancer drugs in the pharmaceutical, food, and cosmetic industries.

Carbon Nanomaterials for Biomedical Applications: Progress and Outlook

Recent developments in nanoscale materials have found extensive use in various fields, especially in the biomedical industry. Several substantial obstacles must be overcome, particularly those related to nanostructured materials in biomedicine, before they can be used in therapeutic applications. Significant concerns in biomedicine include biological processes, adaptability, toxic effects, and nano-biointerfacial properties. Biomedical researchers have difficulty choosing suitable materials for drug carriers, cancer treatment, and antiviral uses. Carbon nanomaterials are among the various nanoparticle forms that are continually receiving interest for biomedical applications. They are suitable materials owing to their distinctive physical and chemical properties, such as electrical, high-temperature, mechanical, and optical diversification. An individualized, controlled, dependable, low-carcinogenic, target-specific drug delivery system can diagnose and treat infections in biomedical applications. The variety of carbon materials at the nanoscale is remarkable. Allotropes and other forms of the same element, carbon, are represented in nanoscale dimensions. These show promise for a wide range of applications. Carbon nanostructured materials with exceptional mechanical, electrical, and thermal properties include graphene and carbon nanotubes. They can potentially revolutionize industries, including electronics, energy, and medicine. Ongoing investigation and expansion efforts continue to unlock possibilities for these materials, making them a key player in shaping the future of advanced technology. Carbon nanostructured materials explore the potential positive effects of reducing the greenhouse effect. The current state of nanostructured materials in the biomedical sector is covered in this review, along with their synthesis techniques and potential uses.

Monstera deliciosa mediated single step biosynthesis of gold nanoparticles by bottom-up approach and its non-antimicrobial properties

In this study, we have stated the green biosynthesis of gold nanoparticles (AuNPs) by utilizing the extract of Monstera deliciosa leaves (MDL) as a reducing agent. Biosynthesized flat, thin, and single-crystalline gold nanotriangles obtained through centrifugation are then analyzed by different characterization techniques. The UV - visible absorption spectra of AuNPs exhibited maxima bands in the range of 500-590 nm, indicating a characteristic of AuNPs. XRD analysis revealed the formation of the (111)-oriented face-centered cubic (FCC) phase of AuNPs. ATR-IR spectra showed signatures of stretching vibrations of O-H, C-H, C=C, C=O, C-O, and C-N, accompanied by CH3 rocking vibrations present in functional groups of biomolecules. FESEM images confirmed spherical nanoparticles with an average diameter in the range of 53-66 nm and predominantly triangular morphology of synthesized AuNPs within the size range of 420-800 nm. NMR, GC-MS, and HR-MS studies showed the presence of different biomolecules, including phenols, flavonoids, and antioxidants in MDL extracts, which play a crucial role of both, reducing as well as stabilizing and capping agents to form stable AuNPs by a bottom-up approach. They were then investigated for their antibacterial assay against Gram-positive (S. aureus, B. subtilis) and Gram-negative (E. coli, P. aeruginosa) microorganisms, along with testing of antifungal potential against various fungi (Penicillium sp., Aspergillus flavus, Fusarium oxysporum, Rhizoctonia solani) using the well diffusion method. Here, biosynthesized AuNPs showed non-antimicrobial properties against all four used bacteria and fungi, showing their suitability as a contender for biomedical applications in drug delivery ascribed to their inert and biocompatible nature.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03898-0.

Electrochemical investigations and antimicrobial activity of Au nanoparticles photodeposited on titania nanoparticles

Titanium oxide nanopowder (TiO2 NPs) was synthesized via anodization in 0.7 M perchloric acid then annealed in nitrogen at 450 °C for 3 h to prepared the Titanium Oxide Nitrogen annealed nanoparticles (TiO2 NPs-N2) powder as catalytic support. Using a photodeposition process, gold was added with isopropanol as a sacrificial donor and H[AuCl4] acid, producing gold nanoparticles on nitrogen-annealed titanium oxide nanoparticles (Au-NPs on TiO2-NPs-N2). The mass loading of Au NPs was 2.86 × 10-4 (g/cm2). TEM images of Au NPs on TiO2-NPs-N2 suggest circular particles with a tendency to agglomerate. Cyclic voltammetry (CV) was used to investigate the electrocatalytic performance of the Au NPs/TiO2-NPs-N2 catalysts in ferrocyanide, KOH, and H2SO4, and the results were compared to those of a polycrystalline Au electrode that is readily accessible in the market. In KOH, H2SO4, and (2 M KOH + 0.1 M glycerol) solutions, the Au NPs/TiO2-NPs-N2 electrode displayed a startlingly high electrocatalytic performance. Using CV, the electrocatalytic oxygen reduction reaction (ORR) of Au NPs/TiO2-NPs-N2 and Au-NPs against glycerol oxidation in basic media was studied. The results indicated that Au NPs/TiO2-NPs-N2 is a promising support material for improving the electrocatalytic activity for acidic and basic oxidation. The electrode made of Au NPs/TiO2-NTs-N2 has steady electrocatalytic activity and may be reused repeatedly. TiO2 NPs and Au NPs/TiO2NPs-N2 showed satisfactory antibacterial activity against some human pathogenic bacteria using the disc diffusion method.

From nature to nanotechnology: The interplay of traditional medicine, green chemistry, and biogenic metallic phytonanoparticles in modern healthcare innovation and sustainability

As we navigate the modern era, the intersection of time-honoured natural remedies and contemporary scientific approaches forms a burgeoning frontier in global healthcare. For generations, natural products have been foundational to health solutions, serving as the primary healthcare choice for 80% to 85% of the world's population. These herbal-based, nature-derived substances, significant across diverse geographies, necessitate a renewed emphasis on enhancing their quality, efficacy, and safety. In the current century, the advent of biogenic phytonanoparticles has emerged as an innovative therapeutic conduit, perfectly aligning with principles of environmental safety and scientific ingenuity. Utilizing green chemistry techniques, a spectrum of metallic nanoparticles including elements such as copper, silver, iron, zinc, and titanium oxide can be produced with attributes of non-toxicity, sustainability, and economic efficiency. Sophisticated herb-mediated processes yield an array of plant-originated nanomaterials, each demonstrating unique physical, chemical, and biological characteristics. These attributes herald new therapeutic potentials, encompassing antioxidants, anti-aging applications, and more. Modern technology further accelerates the synthesis of natural products within laboratory settings, providing an efficient alternative to conventional isolation methods. The collaboration between traditional wisdom and advanced methodologies now signals a new epoch in healthcare. Here, the augmentation of traditional medicine is realized through rigorous scientific examination. By intertwining ethical considerations, cutting-edge technology, and natural philosophy, the realms of biogenic phytonanoparticles and traditional medicine forge promising pathways for research, development, and healing. The narrative of this seamless integration marks an exciting evolution in healthcare, where the fusion of sustainability and innovation crafts a future filled with endless possibilities for human well-being. The research in the development of metallic nanoparticles is crucial for unlocking their potential in revolutionizing fields such as medicine, catalysis, and electronics, promising groundbreaking applications with enhanced efficiency and tailored functionalities in future technologies. This exploration is essential for harnessing the unique properties of metallic nanoparticles to address pressing challenges and advance innovations across diverse scientific and industrial domains.

Effect of Mangifera Indica (Mango) on Dental Caries: A Systematic Review

The present study aimed to evaluate the effect of Mangifera indica (mango) on dental caries. The entire plant, including the leaves, fruit, roots, and flowers, has various therapeutic characteristics used for centuries to cure various illnesses. This systematic review aimed to identify an inexpensive, simple, and effective method of preventing and controlling dental caries. The search was performed among the studies written in English, the database of abstracts concentrating on the effects of Mangifera indica (Mango) on dental caries detected in Pubmed, Scopus, Google Scholar, and Central. In total, we find 37 articles. The relevant English language articles published up to August 2022 were collected, screened, and reviewed. Search words contained "Mangifera indica" and "dental caries" or "Streptococcus mutans" or "tooth demineralization." For our systematic review analysis, we included 3 randomized controlled trial studies studying a total of 130 people, of whom 110 were children aged 8 to 14 and 20 were adults aged 20 to 25. These experiments all employed mouthwash containing an extract from Mangifera indica. In conclusion, it has been proven in 2 separate studies that saliva's PH will increase significantly. In addition, a reduction of S. mutants has been observed in another research. Overall, it was concluded that mango extract mouthwash is highly effective in decreasing the bacteria that can cause dental caries. however, we firmly believe that conduction of more detailed in vivo studies regarding Mangifera indica implications in dental caries treatment is essentially needed for further confirmation.

Novel Perspectives on Food-Based Natural Antimicrobials: A Review of Recent Findings Published since 2020

Various fruit and vegetable wastes, particularly peels, seeds, pulp, and unprocessed residues from the food industry, are abundant sources of antioxidants and essential antimicrobial agents. These valuable bioactive compounds recovered from the food industry have a great application in food, agriculture, medicine, and pharmacology. Food-derived natural antimicrobials offer advantages such as diminishing microbial loads and prolonging the shelf life of food products particularly prone to microbial spoilage. They not only enrich the foods with antioxidants but also help prevent microbial contamination, thereby prolonging their shelf life. Similarly, incorporating these natural antimicrobials into food packaging products extends the shelf life of meat products. Moreover, in agricultural practices, these natural antimicrobials act as eco-friendly pesticides, eliminating phytopathogenic microbes responsible for causing plant diseases. In medicine and pharmacology, they are being explored as potential therapeutic agents. This review article is based on current studies conducted in the last four years, evaluating the effectiveness of food-based natural antimicrobials in food, agriculture, medicine, and pharmacology.

Synergy of Plant Essential Oils in Antibiotic Therapy to Combat Klebsiella pneumoniae Infections

Increased antibiotic resistance presents a health problem worldwide. The World Health Organization published a list of pathogens considered a priority for designing new treatments. Klebsiella pneumoniae (Kp) is a top-priority microorganism, highlighting the strains that produce carbapenemases. Developing new efficient therapies or complementing existing treatments is a priority, and essential oils (EOs) provide an alternative. EOs could act as antibiotic adjuvants and enhance antibiotic activity. Employing standard methodologies, the antibacterial activity of the EOs and their synergic effect with antibiotics were detected. A string test was used to identify the impact of the EOs over the hypermucoviscosity phenotype presented by Kp strains, and Gas Chromatography-Mass Spectrometry analysis identified EOs and the composition of EOs. The potential of EOs for designing synergistic therapies with antibiotics to combat the infection of KPC diseases was demonstrated. In addition, the alteration of the hypermucoviscosity phenotype was shown as the principal mechanism of a synergic action between EOs and antibiotics. The differential composition of the EOs lets us identify some molecules that will be analyzed. Synergic activity of EOs and antibiotics can provide a solid platform for combating multiresistant pathogens that represent a severe health sector problem, such as Kp infections.

Surface Functionalization of Bioactive Hybrid Adsorbents for Enhanced Adsorption of Organic Dyes

In this study, a valuable adsorbent was functionalized using commercial ZnO and a mango seed extract (MS-Ext) as a green approach for synthesis. Fourier-transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, and energy-dispersive X-ray analysis spectraconfirmed the presence of bioactive phenolic compounds and Cu2+ ions on the surface of ZnO. Functionalized Cu-doped ZnO/MS-Ext exhibits high efficacy in acidic, neutral, and alkaline medium, as indicated by 98.3% and 93.7% removal of methylene blue (MB) and crystal violet (CV) dyes, respectively. Cu-doped ZnO/MS-Ext has a zeta potential significantly lower than pristine zinc oxide (p-ZnO), which results in enhanced adsorption of cationic MB and CV dyes. In binary systems, both MB and CV were significantly removed in acidic and alkaline media, with 92% and 87% being removed for CV in acidic and alkaline media, respectively. In contrast, the removal efficiency of methyl orange dye (MO) was 16.4%, 6.6% and 11.2% for p-ZnO, ZnO/Ext and Cu-doped ZnO/Ext, respectively. In general, the adsorption kinetics of MB on Cu-doped ZnO/MS-Ext follow this order: linear pseudo-second-order (PSO) > nonlinear pseudo-second-order (PSO) > nonlinear Elovich model > linear Elovich model. The Langmuir isotherm represents the adsorption process and indicates that MB, CV, and MO are chemisorbed onto the surface of the adsorbent at localized active centers of the MS-extract functional groups. In a binary system consisting of MB and CV, the maximum adsorption capacity (q_m) was 72.49 mg/g and 46.61 mg/g, respectively. The adsorption mechanism is governed by electrostatic attraction and repulsion, coordination bonds, and π-π interactions between cationic and anionic dyes upon Cu-doped ZnO/Ext surfaces.

Biogenic Preparation and Characterization of Silver Nanoparticles from Seed Kernel of Mangifera indica and Their Antibacterial Potential against Shigella spp

Shigellosis is a serious foodborne diarrheal disease caused by the Shigella species. It is a critical global health issue. In developing countries, shigellosis causes most of the mortality in children below 5 years of age. Globally, around 165 million cases of diarrhea caused by Shigella are reported, which accounts for almost 1 million deaths, in which the majority are recorded in Third World nations. In this study, silver nanoparticles were synthesized using Mangifera indica kernel (MK-AgNPs) seed extracts. The biosynthesized M. indica silver nanoparticles (MK-AgNPs) were characterized using an array of spectroscopic and microscopic tools, such as UV–Vis, scanning electron microscopy, particle size analyzer, Fourier transform infrared spectroscopy, and X-ray diffractometer. The nanoparticles were spherical in shape and the average size was found to be 42.7 nm. The MK-AgNPs exhibited remarkable antibacterial activity against antibiotic-resistant clinical Shigella sp. The minimum inhibitory concentration (MIC) value of the MK-AgNPs was found to be 20 μg/mL against the multi-drug-resistant strain Shigella flexneri. The results clearly demonstrate that MK-AgNPs prepared using M. indica kernel seed extract exhibited significant bactericidal action against pathogenic Shigella species. The biosynthesized nanoparticles from mango kernel could possibly prove therapeutically useful and effective in combating the threat of shigellosis after careful investigation of its toxicity and in vivo efficacy.

The Investigation of the Chemical Composition and Applicability of Gold Nanoparticles Synthesized with Amygdalus communis (Almond) Leaf Aqueous Extract as Antimicrobial and Anticancer Agents

The current work’s main objective was to determine the chemical composition of Amygdalus communis (AC) leaf extract and examine the antibacterial and cytotoxic properties of biosynthesized gold nanoparticles (AuNPs). The chemical composition of AC leaf extract was determined using LC-ESI/MS/MS to detect compounds that may be responsible for the reducing, stabilizing, and capping steps in the synthesis of nanoparticles and their biological activities. The AC-AuNPs were spherical, with a particle size lower than 100 nm and a face-centered cubic structure. The EDX spectrum confirmed the formation of AuNPs and a negative zeta potential value (−27.7 mV) suggested their physicochemical stability. The in vitro cytotoxic efficacy of the AC-AuNPs against colorectal adenocarcinoma (Caco-2), glioma (U118), and ovarian (Skov-3) cancer cell lines and human dermal fibroblasts (HDFs) was evaluated by MTT assay. CaCo-2 cell proliferation was effectively inhibited by the AC-AuNPs at concentrations between 25 and 100 g mL−1. The AC-AuNPs exerted preeminent antimicrobial activity against Bacillus subtilis with an MIC of 0.02 μg/mL, whilst good activity was shown against Staphylococcus aureus bacteria and Candida albicans yeast with an MIC of 0.12 μg/mL. Ultimately, the results support the high antibacterial and anticancer potential of biosynthesized AuNPs from AC leaf extract.

Burdock-Derived Composites Based on Biogenic Gold, Silver Chloride and Zinc Oxide Particles as Green Multifunctional Platforms for Biomedical Applications and Environmental Protection

Green nanotechnology is a rapidly growing field linked to using the principles of green chemistry to design novel nanomaterials with great potential in environmental and health protection. In this work, metal and semiconducting particles (AuNPs, AgClNPs, ZnO, AuZnO, AgClZnO, and AuAgClZnO) were phytosynthesized through a "green" bottom-up approach, using burdock (Arctium lappa L.) aqueous extract. The morphological (SEM/TEM), structural (XRD, SAED), compositional (EDS), optical (UV-Vis absorption and FTIR spectroscopy), photocatalytic, and bio-properties of the prepared composites were analyzed. The particle size was determined by SEM/TEM and by DLS measurements. The phytoparticles presented high and moderate physical stability, evaluated by zeta potential measurements. The investigation of photocatalytic activity of these composites, using Rhodamine B solutions' degradation under solar light irradiation in the presence of prepared powders, showed different degradation efficiencies. Bioevaluation of the obtained composites revealed the antioxidant and antibacterial properties. The tricomponent system AuAgClZnO showed the best antioxidant activity for capturing ROS and ABTS•⁺ radicals, and the best biocidal action against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The "green" developed composites can be considered potential adjuvants in biomedical (antioxidant or biocidal agents) or environmental (as antimicrobial agents and catalysts for degradation of water pollutants) applications.

Recent Advances in Health Benefits of Bioactive Compounds from Food Wastes and By-Products: Biochemical Aspects

Bioactive compounds, including terpenoids, polyphenols, alkaloids and other nitrogen-containing constituents, exert various beneficial effects arising from their antioxidant and anti-inflammatory properties. These compounds can be found in vegetables, fruits, grains, spices and their derived foods and beverages such as tea, olive oil, fruit juices, wine, chocolate and beer. Agricultural production and the food supply chain are major sources of food wastes, which can become resources, as they are rich in bioactive compounds. The aim of this review is to highlight recent articles demonstrating the numerous potential uses of products and by-products of the agro-food supply chain, which can have various applications.

In vitro somatic embryo productions from Curculigo orchioides derived gold nanoparticles: Synthesis, characterization, its biomedical applications, and their eco-friendly approaches to degradation of methylene blue under solar light irradiations

Curculigo orchioides rhizome explants were employed to develop a rapid and effective strategy for increased plant regeneration using somatic embryogenesis. Direct somatic embryo development was shown on rhizome explants cultivated on Murashige and Skoog (MS) making with 2, 4-D (1.0-3.0 mg/L). Rhizome explants cultivated on MS media supplemented with 2.0 mg/L 2, 4-D yielded the highest frequency of embryogenesis (87.5%) and the maximum number of somatic embryos (1596.7/explant). Somatic embryo germination was accomplished using MS media with 2.0 mg/L 6-benzylaminopurine (BAP). With an 80% survival rate, the germination plantlets were acclimated in the greenhouse. The current study is the first evidence of the efficacy of in vitro-produced plants and C. orchioides somatic embryo callus cultures of stable gold nanoparticles. The UV-Vis spectrophotometric absorbance, at 510 nm, revealed the absorption spectra of the AuNPs. The FT-IR revealed functional groups and reaction processes in green AuNP formation. High-resolution transmission electron microscopy (HR-TEM) was used to assess the surface morphology and structure of the AuNPs after their elemental composition was determined using a dispersive energy X-ray (EDAX) spectrum. The average size of AuNPs was around 35 nm in diameter. The crystalline nature of the AuNPs was investigated by X-ray diffraction (XRD). The highest growth inhibition was found for C. orcthioides against Klebsiella pneumoniae (17.5 mm) and Serratia marcescens (16.5 mm). The AuNPs exhibited antioxidant activity against free radicals such as DPPH and ABTS. Furthermore, the cytotoxicity of AuNPs was assessed, and inhibitory concentration (IC₅₀) was 20 μg/mL and 80 μg/mL for breast carcinoma (MDA-MB-231) and Vero cell lines. The degradation of methylene blue measures the photocatalytic activity of the manufactured AuNPs when subjected to visible sunlight (MB). Thus, the result showed a maximum degradation efficiency of MB (84%).

Natural resources for sustainable synthesis of nanomaterials with anticancer applications: A move toward green nanomedicine

Today, researchers have focused on the application of environmentally-benign and sustainable micro- and nanosystems for drug delivery and cancer therapy. Compared to conventional chemotherapeutics, advanced micro- and nanosystems designed by applying abundant, natural, and renewable feedstocks have shown biodegradability, biocompatibility, and low toxicity advantages. However, important aspects of toxicological assessments, clinical translational studies, and suitable functionalization/modification still need to be addressed. Herein, the benefits and challenges of green nanomedicine in cancer nanotherapy and targeted drug delivery are cogitated using nanomaterials designed by exploiting natural and renewable resources. The application of nanomaterials accessed from renewable natural resources, comprising metallic nanomaterials, carbon-based nanomaterials, metal-organic frameworks, natural-derived nanomaterials, etc. for targeted anticancer drug delivery and cancer nanotherapy are deliberated, with emphasis on important limitations/challenges and future perspectives.

Mechanisms of Metallic Nanomaterials to Induce an Antibacterial Effect

Pathogenic microorganisms, including bacteria, are becoming resistant to most existing drugs, which increases the failure of pharmacologic treatment. Therefore, new nanomaterials were studied to spearhead improvement against the same resistant pathogenic bacteria. This has increased the mortality in the world population, principally in under-developed countries. Moreover, recently there has been research to find new drug formulations to kill the most dangerous microorganisms, such as bacteria cells which should avoid the spread of disease. Therefore, lately, investigations have been focusing on nanomaterials because they can exhibit the capacity to show an antibacterial effect. These studies have been trying oriented in their ability to produce an improvement to get antibacterial damage against the same pathogenic bacteria resistance. However, there are many problems with the use of nanoparticles. One of them is understanding how they act against bacteria, "their mechanism(s) action" to induce reduction or even kill the bacterial strains. Therefore, it is essential to understand the specific mechanism(s) of each nanomaterial used to observe the interaction between bacteria cells and nanoparticles. In addition, since nanoparticles can be functionalized with different antibacterial drugs, it is necessary to consider and distinguish the antibacterial activity of the nanoparticles from the antibacterial activity of the drugs to avoid confusion about how the nanoparticles work. Knowledge of these differences can help better understand the applications of the primary nanoparticles (i.e., Ag, Au, CuO, ZnO, and TiO², among others) described in detail in this review which are toxic against various bacterial strains.

Gold Nanoparticles Synthesized with Common Mullein (Verbascum thapsus) and Castor Bean (Ricinus communis) Ethanolic Extracts Displayed Antiproliferative Effects and induced Caspase 3 Activity in Human HT29 and SW480 Cancer Cells

Gold nanoparticles (AuNPs) are promising nanomaterials exhibiting anti-cancer effects. Green AuNPs synthesis using plant extracts can be used to achieve stable and beneficial nanoparticles due to their content of bioactive compounds. This research aimed to synthesize and evaluate the antiproliferative and caspase-3 activity induction of green AuNPs synthesized with common mullein (V. thapsus) flowers (AuNPsME) and castor bean (R. communis) leaves (AuNPsCE) ethanolic extracts in human HT29 and SW480 colorectal cancer cells. Their effect was compared with chemically synthesized AuNPs (AuNPsCS). The extracts mainly contained p-coumaric acid (71.88–79.93 µg/g), ferulic acid (19.07–310.71 µg/g), and rutin (8.14–13.31 µg/g). The obtained nanoparticles presented typical FT-IR bands confirming the inclusion of polyphenols from V. thapsus and R. communis and spherical/quasi-spherical morphologies with diameters in the 20.06–37.14 nm range. The nanoparticles (20–200 µg/mL) showed antiproliferative effects in both cell lines, with AuNPsCE being the most potent (IC50 HT29: 110.10 and IC50SW480: 64.57 µg/mL). The AuNPsCS showed the lowest intracellular reactive oxygen species (ROS) generation in SW480 cells. All treatments induced caspase 3/7 activity to a similar or greater extent than 30 mM H2O2-treated cells. Results indicated the suitability of V. thapsus and R. communis extracts to synthesize AuNPs, displaying a stronger antiproliferative effect than AuNPsCS.

Metallic Structures: Effective Agents to Fight Pathogenic Microorganisms

The current worldwide pandemic caused by coronavirus disease 2019 (COVID-19) had alerted the population to the risk that small microorganisms can create for humankind's wellbeing and survival. All of us have been affected, directly or indirectly, by this situation, and scientists all over the world have been trying to find solutions to fight this virus by killing it or by stop/decrease its spread rate. Numerous kinds of microorganisms have been occasionally created panic in world history, and several solutions have been proposed to stop their spread. Among the most studied antimicrobial solutions, are metals (of different kinds and applied in different formats). In this regard, this review aims to present a recent and comprehensive demonstration of the state-of-the-art in the use of metals, as well as their mechanisms, to fight different pathogens, such as viruses, bacteria, and fungi.

Facile green synthesis of silver nanoparticles using Mangifera indica seed aqueous extract and its antimicrobial, antioxidant and cytotoxic potential (3-in-1 system)

A novel approach for the utilisation of fruit waste is attempted in the present investigation. Mangifera indica seed aqueous extract was utilised for green synthesis of silver nanoparticles (AgNPs). The phytoconstituents in the seed acted as reducing and stabilising agent for AgNP formation. UV-Vis, Zeta potential, FT-IR, XRD, TEM, SAED, EDX analysis were used to characterise the green synthesised AgNPs. UV-vis spectra showed characteristic spectra at 450 nm; XRD and SAED confirmed the crystalline nature while TEM revealed the shape to be round and average size was 26.85 nm. FT-IR revealed functional groups like alcohol or phenols, carboxylic acids, ketones, amines, aromatic amines, aliphatic amines, alkyl halides and alkynes which were responsible for AgNP formation. The nanoparticles showed more antibacterial activity than antifungal activity and antibacterial activity towards Gram-negative bacteria was more than Gram-positive bacteria. Dose dependent antioxidant activity (DPPH, SO and ABTS) and dose dependent cytotoxic effect against HeLa, MCF-7 and normal fibroblast cell lines was envisaged. The green synthesised AgNPs exhibited three different bioactivities (3-in-1 system) i.e. dose dependent antimicrobial, antioxidant and cytotoxic activity. Fruit waste can be successfully utilised for silver nanoparticles formation which can be therapeutically useful and effective.[Figure: see text]HighlightsSilver nanoparticles were synthesised from M. indica fruit waste i.e. seedCharacterisation by spectroscopic techniques: UV-Vis, Zeta, FTIR, XRD, SAED, EDX and TEM analysis.Silver nanoparticles were 26.85 nm in size and round in shapeAntimicrobial activity against 14 microorganismsAntioxidant activity in terms of DPPH, SO and ABTSCytotoxic activity against HeLa, MCF-7 and Fibroblast normal cell lines.