Asymmetric dumbbell-shaped silver nanoparticles and spherical gold nanoparticles green-synthesized by mangosteen (Garcinia mangostana) pericarp waste extracts

Crucial physicochemical factors mediating mitochondrial toxicity of nanoparticles at noncytotoxic concentration

Nanomaterials have been extensively applied in multiple industries, among which silver nanoparticles (AgNPs), silicon dioxide nanoparticles (SiNPs), and gold nanoparticles (AuNPs) have become representative of widely consumed NPs. Limited knowledge is available regarding the subcellular responses of NPs with different physicochemical properties, i.e. material type and size, under the noncytotoxic concentrations. Macrophages are important sensitive cells exposed to NPs, and mitochondria are sensitive organelles that respond at the subcellular level. Herein, we found that sublethal concentrations of AgNPs and SiNPs, not AuNPs, decreased the mitochondrial membrane potential (MMP) and tubular mitochondria, and further resulted in an increase of ROS level and a decrease of ATP generation. AgNPs and SiNPs can also disturb mitochondrial dynamics manifested as increasing Mfn2 expression and decreasing Drp1 expression. Further assessments for mitochondrial function showed that AgNPs and SiNPs exposure led to a decrease in the gene expressions related to complex I (Ndufa8 and Ndufs2), complex III (Uqcrc2 and Uqcrfs1), complex IV (Cox6b1), and activity of complex I, suggesting their potential roles in impairing cellular respiration. In terms of the effects of NPs with different sizes, stronger toxicity was observed in smaller-sized nanoparticles. Among the above mitochondrial changes, we identified that ROS, ATP, MMP, tubular mitochondria, and expression of Drp1 were relatively sensitive indicators in subcellular response to NPs. With the above sensitive indicators, the comparison of heterogeneity between material type and size of the NPs showed that material type occupied a main influence on subcellular mitochondrial effects. Our finding provided important data on the potential subcellular risks of NPs, and indicated the vital role of material type for a better understanding of the nanomaterial biological safety.

Potential usage of biosynthesized zinc oxide nanoparticles from mangosteen peel ethanol extract to inhibit Xanthomonas oryzae and promote rice growth

In recent decades, the biosynthesis of nanoparticles using biological agents, such as plant extracts, has grown in popularity due to their environmental and economic benefits. Therefore, this study investigated into utilizing ethanol crude extract sourced from mangosteen peel for the synthesis of zinc oxide nanoparticles (ZnO NPs) and assessing their efficacy against the rice blight pathogen (Xanthomonas oryzae pv. oryzae) through antibacterial evaluations. Additionally, the effects of the synthesized ZnO NPs on rice plant growth was investigated. The X-ray diffraction analysis revealed the production of wurtzite ZnO NPs under specific synthesis conditions, exhibiting a crystallite size of 38.71 nm (or 387.122 Å) without any contamination. Analysis of the ultraviolet-visible optical absorption spectrum indicated a characteristic absorption peak at 363 nm, suggesting a calculated band gap energy of 2.88 eV for the ZnO NPs. Furthermore, Fourier transform infrared spectroscopy analysis confirmed the presence of active compounds functional groups from mangosteen peel in the synthesized ZnO NPs. These biosynthesized ZnO NPs demonstrated significant inhibition of X. oryzae pv. oryzae growth, exhibiting an in vitro 50 % inhibitory concentration (IC50) value of 1.895 mg/mL and a minimum inhibitory concentration (MIC) value of 4 mg/mL. The ZnO NPs treatments at two-fold IC50 values significantly enhanced root length, dry biomass, and chlorophyll a content in rice plants. Consequently, the results demonstrated the potential application of biosynthesized ZnO NPs from mangosteen peel extract in green agriculture, as an alternative to excessive antibiotic use, for combating bacterial plant diseases, and for enhancing plant growth.

Facile green synthesis of wasted hop-based zinc oxide nanozymes as peroxidase-like catalysts for colorimetric analysis

Hops are a common ingredient in beer production, and a considerable quantity of hops is usually discarded as a waste material once the brewing process is completed. Transforming this waste material into valuable nanomaterials offers a sustainable approach that has the potential to significantly mitigate environmental impact. Herein, a facile and green protocol for the production of zinc oxide nanozymes (ZnO NZs) using wasted hop extract (WHE) as a natural precursor was demonstrated. The process involved a hydrothermal synthesis method followed by a calcination step to form the final ZnO NZs. The results revealed that lupulon, the main β-acid in hops, particularly the phenolic hydroxy group, is primarily responsible for the biosynthesis of ZnO NZs. The WHE-ZnO NZs exhibited exceptional peroxidase-like (POD-like) activity and served as effective catalysts for the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H2O2). Analysis of the catalytic mechanism revealed that the POD-like activity of these WHE-ZnO NZs originated from their ability to expedite the transfer of electrons between TMB and H2O2, resulting in the enzymatic kinetics following the standard Michaelis-Menten mechanism. Furthermore, we developed a straightforward and user-friendly colorimetric technique for detecting both H2O2 and glucose. By utilizing the WHE-ZnO NZs as POD-like catalysts, we achieved a linear detection range of 1-1000 μM and a limit of detection of 0.24 μM (S/N = 3) for H2O2 detection and a linear range of 0-100 mM and a detection limit of 16.73 μM (S/N = 3) for glucose detection. These results highlighted the potential applications of our waste-to-resource approach for nanozyme synthesis in the field of analytical chemistry.

Synthesis of Au-Ag bimetallic nanoparticles using Korean red ginseng (Panax ginseng Meyer) root extract for chemo-photothermal anticancer therapy

Green synthesis strategies have been widely applied for the preparation of versatile nanomaterials. Gold nanospheres with an average size of 6.95 ± 2.25 nm were green synthesized by using a 70% ethanol extract of Korean red ginseng (Panax ginseng Meyer) root as a reducing agent. A seed-mediated synthesis was conducted to prepare Au-Ag bimetallic nanoparticles using gold nanospheres as seeds. Remarkably, Au-Ag bimetallic nanoparticles with an average size of 80.4 ± 11.9 nm were synthesized. Scanning transmission electron microscopy, energy dispersive X-ray spectroscopy and elemental mappings revealed bimetallic nanoparticles with Au-Ag alloy core and Au-rich shells. A face-centered cubic structure of Au-Ag bimetallic nanoparticles was confirmed by X-ray diffraction analysis. For Au-Ag bimetallic nanoparticles, the ratio of Ag/Au was 0.20 which was detected and analyzed by inductively coupled plasma-mass spectrometry. Gold nanospheres and Au-Ag bimetallic nanoparticles were functionalized by PEGylation, folic acid conjugation and grafting onto graphene oxide. Finally, docetaxel was loaded for evaluating the in vitro cell viability on cancer cells. Successful functionalization was confirmed by Fourier-transform infrared spectra. The anticancer activity of the docetaxel-loaded nanoparticles was higher than that of their non-docetaxel-loaded counterparts. The highest anticancer activity on human gastric adenocarcinoma cells (AGS) was observed in the docetaxel-loaded gold nanospheres that were functionalized by PEGylation, folic acid conjugation and grafting onto graphene oxide. Additionally, grafting onto graphene oxide and docetaxel loading induced high intracellular reactive oxygen species generation. For chemo-photothermal (PTT) anticancer therapy, cell viability was investigated using near-infrared laser irradiation at 808 nm. The highest chemo-PTT anticancer activity on AGS cells was observed in the docetaxel-loaded Au-Ag bimetallic nanoparticles. Therefore, the newly prepared docetaxel-loaded Au-Ag bimetallic nanoparticles in the current report have potential applications in chemo-PTT anticancer therapy.

Biosynthesis of Gold and Silver Nanoparticles Using Phytochemical Compounds

Gold and silver nanoparticles are nanoparticles that have been widely used in various fields and have shown good benefits. The method of nanoparticle biosynthesis utilizing plant extracts, also known as green synthesis, has become a promising method considering the advantages it has compared to other synthesis methods. This review aims to give an overview of the phytochemical compounds in plants used in the synthesis of gold and silver nanoparticles, the nanoparticle properties produced using plant extracts based on the concentration and structure of phytochemical compounds, and their applications. Phytochemical compounds play an important role as reducing agents and stabilizers in the stages of the synthesis of nanoparticles. Polyphenol compounds, reducing sugars, and proteins are the main phytochemical compounds that are responsible for the synthesis of gold and silver nanoparticles. The concentration of phytochemical compounds affects the physical properties, stability, and activity of nanoparticles. This is important to know to be able to overcome limitations in controlling the physical properties of the nanoparticles produced. Based on structure, the phytochemical compounds that have ortho-substituted hydroxyl result in a smaller size and well-defined shape, which can lead to greater activity and stability. Furthermore, the optimal condition of the biosynthesis process is required to gain a successful reaction that includes setting the metal ion concentration, temperature, reaction time, and pH.

Ultra-Small Silver Nanoparticles: A Sustainable Green Synthesis Approach for Antibacterial Activity

The present study centers on the synthesis of ultra-small silver nanoparticles (AgNPs) with antibacterial properties using citrus peel residues (orange, lemon, and grapefruit) as reducing and stabilizing agents, and on assessing their antibacterial activity against multidrug-resistant clinical Staphylococcus aureus. The synthesized AgNPs were analyzed by various techniques, including UV-Vis spectroscopy, SAED, TEM, XRD, FTIR, and Raman. The results demonstrate the formation of ultra-small, monodisperse, quasi-spherical AgNPs with an average particle size of 2.42 nm for AgNPs produced with mixed extracts. XRD analysis indicated that the AgNPs have a crystal size of 9.71 to 16.23 nm. The AgNPs exhibited potent inhibitory activity against resistant S. aureus, with a minimum inhibitory concentration (MIC) of 15.625 to 62.50 ppm. The findings suggest that the ultra-small nanometer size of the AgNPs could be attributed to the synthesis method that employs ambient conditions and the presence of polyphenolic compounds from citrus peel. Consequently, AgNPs obtained through sustainable green synthesis hold significant potential in combating clinical multi-resistant bacterial strains that are challenging to treat and eradicate. This approach also contributes to the revaluation of citrus residues in the region, which is an ongoing environmental issue today.

Metallic and non-metallic nanoparticles from plant, animal, and fisheries wastes: potential and valorization for application in agriculture

Global agriculture is facing tremendous challenges due to climate change. The most predominant amongst these challenges are abiotic and biotic stresses caused by increased incidences of temperature extremes, drought, unseasonal flooding, and pathogens. These threats, mostly due to anthropogenic activities, resulted in severe challenges to crop and livestock production leading to substantial economic losses. It is essential to develop environmentally viable and cost-effective green processes to alleviate these stresses in the crops, livestock, and fisheries. The application of nanomaterials in farming practice to minimize nutrient losses, pest management, and enhance stress resistance capacity is of supreme importance. This paper explores innovative methods for synthesizing metallic and non-metallic nanoparticles using plants, animals, and fisheries wastes and their valorization to mitigate abiotic and biotic stresses and input use efficiency in climate-smart and stress-resilient agriculture including crop plants, livestock, and fisheries.

Facile Green Synthesis of Titanium Dioxide Nanoparticles by Upcycling Mangosteen (Garcinia mangostana) Pericarp Extract

In the present report, green synthesis of titanium dioxide nanoparticles (TiO₂ NPs) was performed by upcycling mangosteen (Garcinia mangostana) pericarp extract (methanol and ethyl acetate extracts). Field emission scanning electron microscopy images revealed an aggregated structure with a highly porous network of TiO₂ NPs. TiO₂ NPs synthesized with ethyl acetate extract (EtOAc-TiO₂ NPs) exhibited more monodispersity and possessed smoother surfaces than the control TiO₂ NPs (Con-TiO₂ NPs) and TiO₂ NPs synthesized with methanol extract (MeOH-TiO₂ NPs). High-resolution X-ray diffraction patterns clearly confirmed that TiO₂ NPs had a crystalline nature. A mixture of anatase and rutile was observed in Con-TiO₂ NPs and MeOH-TiO₂ NPs, while EtOAc-TiO₂ NPs had only anatase with the smallest size (12.50 ± 1.81 nm). Ethyl acetate extract contained the highest amount of α-mangostin; thus, the surface of TiO₂ NPs was functionalized with ethyl acetate extract. The functionalized TiO₂ NPs synthesized with ethyl acetate extract (EtOAc-TiO₂-αm) showed the highest 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl (DPPH) radical scavenging activity. In vitro cell viability on mouse fibroblast cells (NIH3T3) indicated that the newly synthesized TiO₂ NPs did not show any significant cytotoxicity. Therefore, the TiO₂ NPs in the present report have the potential to be used in cosmetic applications such as sunscreens.

Gold Nanoparticle Drug Delivery System: Principle and Application

In recent years, gold nanoparticles (GNPs) have gradually become a major choice of drug delivery cargoes due to unique properties. Compared to traditional bulk solid gold, GNPs have basic physical and chemical advantages, such as a larger surface area-to-volume ratio and easier surface modification. Furthermore, these have excellent biocompatibility, can induce the directional adsorption and enrichment of biological macromolecules, help retain biological macromolecule activity, and cause low harm to the human body. All these make GNPs good drug delivery cargoes. The present study introduces the properties of GNPs, including factors that affect the properties and synthesis. Then, focus was given on the application in drug delivery, not only on the molecular mechanism, but also on the clinical application. Furthermore, the properties and applications of peptide GNPs were also introduced. Finally, the challenges and prospects of GNPs for drug delivery were summarized.

Green Metallic Nanoparticles for Cancer Therapy: Evaluation Models and Cancer Applications

Metal-based nanoparticles are widely used to deliver bioactive molecules and drugs to improve cancer therapy. Several research works have highlighted the synthesis of gold and silver nanoparticles by green chemistry, using biological entities to minimize the use of solvents and control their physicochemical and biological properties. Recent advances in evaluating the anticancer effect of green biogenic Au and Ag nanoparticles are mainly focused on the use of conventional 2D cell culture and in vivo murine models that allow determination of the half-maximal inhibitory concentration, a critical parameter to move forward clinical trials. However, the interaction between nanoparticles and the tumor microenvironment is not yet fully understood. Therefore, it is necessary to develop more human-like evaluation models or to improve the existing ones for a better understanding of the molecular bases of cancer. This review provides recent advances in biosynthesized Au and Ag nanoparticles for seven of the most common and relevant cancers and their biological assessment. In addition, it provides a general idea of the in silico, in vitro, ex vivo, and in vivo models used for the anticancer evaluation of green biogenic metal-based nanoparticles.

Hg(II) sensing, catalytic, antioxidant, antimicrobial, and anticancer potential of Garcinia mangostana and α-mangostin mediated silver nanoparticles

This study reports synthesis of Garcinia mangostana fruit pericarp (unwanted waste material) and α-mangostin mediated silver nanoparticles (AgNPs). These AgNPs were efficiently produced using 1:10 (extract and salt) ratio under stirring and heating, which was confirmed by surface plasmon resonance (SPR) band in UV-Visible spectroscopic analysis, and size of 73-91 nm determined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The synthesized AgNPs were used for Hg(II) detection in tap water, where the limits of detection and quantification were 2.6 μM and 8.9 μM, respectively. Furthermore, the subject AgNPs showed promising catalytic activity in the reduction of dyes and food colours including Congo red (CR), methylene blue (MB), malachite green (MG), methyl orange (MO), para-nitrophenol (PNP), rhodamine B (RdB), zarda yellow (ZY), deep green (DG), and bright red (BR). The synthesized AgNPs were also evaluated for their antioxidant, antimicrobial, and anticancer properties, where α-mangostin and its nanoparticles (Mang-AgNPs) exhibited promising IC₅₀ values of 14.1 and 13.5 μg/mL, respectively against DU-145 cell line validated by in silico molecular docking study. This study is the first report highlighting the application of AgNPs of G. mangostana fruit pericarp extracts, and α-mangostin in Hg(II) detection, dyes degradation, and anticancer potential against DU-145. Finding of this study suggested the suitability of AgNPs as promising solid biosensor in Hg(II) metal detection, dyes reduction, and target in anticancer drug development.

Diallyl disulphide-loaded spherical gold nanoparticles and acorn-like silver nanoparticles synthesised using onion extract: catalytic activity and cytotoxicity

Onion (Allium cepa) extract was used for the green synthesis of gold and silver nanoparticles. Each colloidal solution exhibited surface plasmon resonance, with a peak at 532 nm for gold nanoparticles and 391 nm for silver nanoparticles. Microscopic results confirmed the presence of spherical shapes. The X-ray diffraction pattern demonstrated a face-centered cubic structure. Both nanoparticles had negative zeta potentials and retained colloidal stability in cell culture medium. Catalytic applications were evaluated for 4-nitrophenol reduction and methyl orange degradation reactions by monitoring with UV-visible spectrophotometry. Furthermore, the nanoparticles demonstrated no significant cytotoxicity against human pancreas ductal adenocarcinoma cells (PANC-1) and human colorectal adenocarcinoma cells (HT-29). PEGylation and diallyl disulphide loading of the gold and silver nanoparticles meaningfully reduced the cell viability of both cell lines. Furthermore, diallyl disulphide loading resulted in more cytotoxicity against PANC-1 cells than against HT-29 cells. Additionally, the gold nanoparticles were more cytotoxic than the silver nanoparticles upon diallyl disulphide loading. Interestingly, after PEGylation and diallyl disulphide loading, the silver nanoparticles exhibited acorn-like shapes, while the gold nanoparticles retained spherical shapes. This result suggested that nanoparticles green-synthesised by onion extract have possibilities as nanocatalysts and drug delivery nanocarriers for catalytic and nanomedicine applications.

Recent progress in plant-gold nanoparticles fabrication methods and bio-applications

The preparation of gold nanoparticles via green routes applying plant extracts as the reducing agents and stabilizers has received broad interest in the last decades. Plant-gold nanoparticles have been well-developed and applied in biochemical and medical research, but there are still challenges that must be overcome. The main challenges include the construction of chemically-robust plant-gold nanoparticles, the precise design of biomimetic surfaces to fabricate nanozymes with high catalytic activities, and the development of approaches to construct biosensors with high selectivities and sensitivities. The cores and surfaces of plant-gold nanoparticles must be considered, as well as their catalytic activities and biosensing mechanisms. This review highlights the latest achievements in plant-gold nanoparticle preparation, heterogeneous nucleation, and surface functionalization, while also focusing on their optical properties and various biological and catalytic activities. Moreover, their antioxidant and cell apoptosis mechanisms, and biological activities are described. Plant-gold nanoparticles have shown great potential in high-performance analytical assays, high-activity catalysts, effective intracellular imaging, and clinical treatment.

Cytotoxic Effect of Silver Nanoparticles Synthesized by Green Methods in Cancer

Cancer is a major public health problem, but despite the several treatment approaches available, patients develop resistance in short time periods, making overcoming resistance or finding more efficient treatments an imperative challenge. Silver nanoparticles (AgNPs) have been described as an alternative option due to their physicochemical properties. The scope of this review was to systematize the available scientific information concerning these characteristics in AgNPs synthesized according to green chemistry's recommendations as well as their cytotoxicity in different cancer models. This is the first paper analyzing, correlating, and summarizing AgNPs' main parameters that modulate their cellular effect, including size, shape, capping, and surface plasmon resonance profile, dose range, and exposure time. It highlights the strong dependence of AgNPs' cytotoxic effects on their characteristics and tumor model, making evident the strong need of standardization and full characterization. AgNPs' application in oncology research is a new, open, and promising field and needs additional studies.

Green Synthesis of Gold Nanoparticles Mediated by Garcinia Fruits andTheir Biological Applications

Background: Green synthesis of gold nanoparticles (AuNPs) using medicinal plant extract is an emerging area of research due to their applicability in nanomedicines. Methods: In this study, aqueous extracts prepared from fruit-pericarps of two Garcinia species, G. indica (GI) and G. cambogia (GC) fruits which are important medicinally and commercially have been utilized for the synthesis of AuNPs. Various analytical techniques were utilized to characterize the synthesized AuNPs. The synthesized AuNPs were investigated for their biological properties such as antioxidant activity using the (2,2-diphenyl-1-picrylhydrazyl) DPPH model, cytotoxicity against MCF-7 (breast) cancer cell line, and antibacterial activity against two bacterial strains viz. B. subtilis and E. coli. Results: The absorption peak of the AuNPs is observed at 541 nm using UV–Visible spectroscopy. The high resolution – scanning electron microscopy images showed spherical with a triangular shape AuNPs and their average sizes were ranging from 2 – 10 nm and it was found to be in good agreement with the particle size of 8 – 11 nm determined using X-ray diffraction analysis. Fourier-transform infrared spectroscopy revealed that water-soluble biomolecules from the aqueous extracts of the Garcinia species played a crucial role in the formation of AuNPs. The synthesized AuNPs exhibited considerable cytotoxicity with IC50 values 34.55 µg/ml (GI) and 35.69 µg/ml (GC) against the MCF-7 cancer cell line. Furthermore, synthesized AuNPs also demonstrated significant antioxidant and antibacterial properties comparable to the standards used. Conclusion: AuNPs have been synthesized using a simple green approach. The synthesized AuNPs demonstrated promising cytotoxicity, antioxidant, and antibacterial properties.

Biogenic nanoparticles: a comprehensive perspective in synthesis, characterization, application and its challenges

BACKGROUND

Translating the conventional scientific concepts into a new robust invention is a much needed one at a present scenario to develop some novel materials with intriguing properties. Particles in nanoscale exhibit superior activity than their bulk counterpart. This unique feature is intensively utilized in physical, chemical, and biological sectors. Each metal is holding unique optical properties that can be utilized to synthesize metallic nanoparticles. At present, versatile nanoparticles were synthesized through chemical and biological methods. Metallic nanoparticles pose numerous scientific merits and have promising industrial applications. But concerning the pros and cons of metallic nanoparticle synthesis methods, researchers elevate to drive the synthesis process of nanoparticles through the utilization of plant resources as a substitute for use of chemicals and reagents under the theme of green chemistry. These synthesized nanoparticles exhibit superior antimicrobial, anticancer, larvicidal, leishmaniasis, wound healing, antioxidant, and as a sensor. Therefore, the utilization of such conceptualized nanoparticles in treating infectious and environmental applications is a warranted one.

CONCLUSION

Green chemistry is a keen prudence method, in which bioresources is used as a template for the synthesis of nanoparticles. Therefore, in this review, we exclusively update the context of plant-based metallic nanoparticle synthesis, characterization, and applications in detailed coverage. Hopefully, our review will be modernizing the recent trends going on in metallic nanoparticles synthesis for the blooming research fraternities.

Dietary flavonoids: Nano delivery and nanoparticles for cancer therapy

Application of nanotechnologies to cancer therapy might increase solubility and/or bioavailability of bioactive compounds of natural or synthetic origin and offers other potential benefits in cancer therapy, including selective targeting. In the present review we aim to evaluate in vivo studies on the anticancer activity of nanoparticles (NPs) obtained from food-derived flavonoids. From a systematic search a total of 60 studies were identified. Most of the studies involved the flavanol epigallocatechin-3-O-gallate and the flavonol quercetin, in both delivery and co-delivery (with anti-cancer drugs) systems. Moreover, some studies investigated the effects of other flavonoids, such as anthocyanins aglycones anthocyanidins, flavanones, flavones and isoflavonoids. NPs inhibited tumor growth in both xenograft and chemical-induced animal models of cancerogenesis. Encapsulation improved bioavailability and/or reduced toxicity of both flavonoids and/or co-delivered drugs, such as doxorubicin, docetaxel, paclitaxel, honokiol and vincristine. Moreover, flavonoids have been successfully applied in molecular targeted nanosystems. Selectivity for cancer cells involves pH- and/or reactive oxygen species-mediated mechanisms. Furthermore, flavonoids are good candidates as drug delivery for anticancer drugs in green synthesis systems. In conclusion, although human studies are needed, NPs obtained from food-derived flavonoids have promising anticancer effects in vivo.

Sesquiterpenoids from Tussilago farfara Flower Bud Extract for the Eco-Friendly Synthesis of Silver and Gold Nanoparticles Possessing Antibacterial and Anticancer Activities

Sesquiterpenoids from the flower bud extract of Tussilago farfara were effectively utilized as a reducing agent for eco-friendly synthesis of silver and gold nanoparticles. The silver and gold nanoparticles had a characteristic surface plasmon resonance at 416 nm and 538 nm, respectively. Microscopic images revealed that both nanoparticles were spherical, and their size was measured to be 13.57 ± 3.26 nm for the silver nanoparticles and 18.20 ± 4.11 nm for the gold nanoparticles. The crystal structure was determined to be face-centered cubic by X-ray diffraction. Colloidal stability of the nanoparticle solution was retained in a full medium, which was used in the cell culture experiment. The antibacterial activity result demonstrated that the silver nanoparticles showed better activity (two- to four-fold enhancement) than the extract alone on both Gram-positive and Gram-negative bacteria. Interestingly, the highest antibacterial activity was obtained against vancomycin-resistant Enterococci Van-A type Enterococcus faecium. Cytotoxicity on cancer cell lines confirmed that gold nanoparticles were more cytotoxic than silver nanoparticles. The highest cytotoxicity was observed on human pancreas ductal adenocarcinoma cells. Therefore, both nanoparticles synthesized with the sesquiterpenoids from T. farfara flower bud extract can be applicable as drug delivery vehicles of anticancer or antibacterial agents for future nanomedicine applications.

Valorization of mangosteen, "The Queen of Fruits," and new advances in postharvest and in food and engineering applications: A review

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This review highlights recent advances of mangosteen research in the postharvest, food and engineering fields.

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In postharvest fields, phytohormones, metabolites, and pest/disease management are described.

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Mangosteen has also been used in various food products and for animal feed supplementation.

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In engineering, mangosteen extract is useful in solar cells, carbon dots and advanced materials.

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Mangosteen-based products may benefit consumers and the engineering and biomedical industries.

One of the most prolific plants utilized in various applications is mangosteen (Garcinia mangostana L.). Rich in potent bioactive compounds, such as xanthones, mangosteen is known to possess pharmacologically important anti-inflammatory and anti-tumor properties. However, most previous reviews have only discussed the application of mangosteen in medicinal areas, yet more recent studies have diverged and valorized its usage in other scientific fields. In this review, the utilization of this exotic fruit in postharvest biology (phytohormone roles, metabolite profiling, bioactive compounds, isolation method optimization, chemical contaminant identification, and management of pests and fruit disorders), food science (food products, animal feed supplementation, and food shelf-life determination), and engineering fields (fabric and solar cell dyes, carbon dots, activated carbon, and biomedical advanced materials) is presented in detail. Research papers published from 2016 onward were selected and reviewed to show the recent research trends in these areas. In conclusion, mangosteen has been utilized for various purposes, ranging from usage in industrially important products to applications in advanced technologies and biomedical innovation.

Shape-dependent cytotoxicity and cellular uptake of gold nanoparticles synthesized using green tea extract

In the present report, three different shapes of chitosan-capped gold nanoparticles (nanospheres, nanostars, and nanorods) were synthesized to investigate the effects of shape on cytotoxicity and cellular uptake in cancer cells. Green tea extract was utilized as a reducing agent to reduce gold salts to gold nanospheres. Gold nanostars were prepared using an as-prepared nanosphere solution as a seed solution. Gold nanorods were synthesized using a conventional method. All three types of gold nanoparticles showed their characteristic surface plasmon resonance bands upon UV-visible spectrophotometry. In high-resolution transmission electron microscopy images, lattice structures were clearly observed in all three shapes, confirming the crystalline nature of the nanoparticles. All three colloidal solutions of gold nanoparticles retained colloidal stability in various solutions. To assess cytotoxicity, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed on four cancer cell lines. The cytotoxicity was the highest in nanorods, followed by nanostars and finally nanospheres. The cellular uptake of gold nanoparticles in human hepatocyte carcinoma cells (HepG2) was measured, and the results followed the order nanospheres > nanorods > nanostars. The outcomes of the current study may assist in the shape design of gold nanoparticles for therapeutic applications as drug delivery vehicles in the field of nanomedicine.

Assessing the antioxidant, cytotoxic, apoptotic and wound healing properties of silver nanoparticles green-synthesized by plant extracts

We synthesized silver nanoparticles using thirty Chinese plant extracts via a green synthetic strategy. UV-visible spectra showed that the silver nanoparticles have an absorbance at 450 nm. Among the thirty extracts, seven extracts (Cratoxylum formosum, Phoebe lanceolata, Scurrula parasitica, Ceratostigma minus, Mucuna birdwoodiana, Myrsine africana and Lindera strychnifolia) exhibited the successful synthesis of silver nanoparticles. These seven extracts showed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and reducing power than the other extracts. The silver nanoparticles synthesized using these seven extracts were mostly spherical with high colloidal stability. The cytotoxicity of these seven silver nanoparticle samples on human lung cancer cells (A549) was clearly higher than that of the extracts alone. Furthermore, the cytotoxicity was affected by the presence or absence of fetal bovine serum. Moreover, the cytotoxicity of the silver nanoparticles synthesized with Cratoxylum formosum and Mucuna birdwoodiana extracts resulted in apoptotic cell death in A549 cells. The wound healing activity observed by the cell scratch method on mouse fibroblast cells (NIH3T3) suggested that the Lindera strychnifolia extract produced silver nanoparticles with decent activity. These results provide ample and systematic information for researchers on the green synthesis of silver nanoparticles using plant extracts.

Biological Effect of Organically Coated Grias neuberthii and Persea americana Silver Nanoparticles on HeLa and MCF-7 Cancer Cell Lines

The aim of this study was to assess the biological effect of organically coated Grias neuberthii (piton) fruit and Persea americana (avocado) leaves nanoparticles (NPs) on cervical cancer (HeLa) and breast adenocarcinoma (MCF-7) cells with an emphasis on gene expression (p53 transcription factor and glutathione-S-transferase GST) and cell viability. UV-Vis spectroscopy analysis showed that synthesized AgNPs remained partially stable under cell culture conditions. HeLa cells remained viable when exposed to piton and avocado AgNPs. A statistically significant, dose-dependent cytotoxic response to both AgNPs was found on the breast cancer (MCF-7) cell line at concentrations above 50 µM. While expression levels of transcription factor p53 showed downregulation in treated MCF-7 and HeLa cells, GST expression was not affected in both cell lines treated. Cell viability assays along with gene expression levels in treated MCF-7 cells support a cancer cell population undergoing cell cycle arrest. The selective toxicity of biosynthesized piton/avocado AgNPs on MCF-7 cells might be of value for novel therapeutics.

Highly stable gold nanoparticles green-synthesized by upcycling cartilage waste extract from yellow-nose skate (Dipturus chilensis) and evaluation of its cytotoxicity, haemocompatibility and antioxidant activity

Skate (Dipturus chilensis) cartilage extract was utilized as a green reducing agent for the synthesis of spherical gold nanoparticles with an average size of 16.7 ± 0.2 nm. The gold nanoparticle solution showed a surface plasmon resonance at 543 nm with a wine-red colour. A strong X-ray diffraction pattern and clear lattice structure in high-resolution transmission electron microscopy indicated a face-centred cubic structure of the gold nanoparticles. The gold nanoparticles retained excellent colloidal stability. Gold nanoparticles showed strong antioxidant activity in terms of 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity. In vitro cytotoxicity was observed for seven cancer cells assessed by the water-soluble tetrazolium assay. Among the seven cancer cells, the highest cytotoxicity was observed for MDA-MB-231 (human breast adenocarcinoma cell) followed by HeLa (human epithelial cervix adenocarcinoma cell) and lastly by HT-29 (human colorectal adenocarcinoma cell). Furthermore, gold nanoparticles showed excellent haemocompatibility, indicating the possibility of their use as a future nanomedicine. These results strongly suggest that gold nanoparticles green-synthesized by upcycling skate cartilage waste extract will be valuable carriers or vehicles for the delivery of drugs or bioactive molecules, such as anti-cancer agents, for the treatment of cancers.

Recent developments in solid lipid nanoparticle and surface-modified solid lipid nanoparticle delivery systems for oral delivery of phyto-bioactive compounds in various chronic diseases

Solid lipid nanoparticle (SLN) delivery systems have a wide applicability in the delivery of phyto-bioactive compounds to treat various chronic diseases, including diabetes, cancer, obesity and neurodegenerative diseases. The multiple benefits of SLN delivery include improved stability, smaller particle size, leaching prevention and enhanced lymphatic uptake of the bioactive compounds through oral delivery. However, the burst release makes the SLN delivery systems inadequate for the oral delivery of various phyto-bioactive compounds that can treat such chronic diseases. Recently, the surface-modified SLN (SMSLN) was observed to overcome this limitation for oral delivery of phyto-bioactive compounds, and there is growing evidence of an enhanced uptake of curcumin delivered orally via SMSLNs in the brain. This review focuses on different SLN and SMSLN systems that are useful for oral delivery of phyto-bioactive compounds to treat various chronic diseases.