Role of Ribes khorassanicum in the biosynthesis of AgNPs and their antibacterial properties

Plant Gel-Mediated Synthesis of Gold-Coated Nanoceria Using Ferula gummosa: Characterization and Estimation of Its Cellular Toxicity toward Breast Cancer Cell Lines

In this study, a novel method using Ferula gummosa gums as a capping agent was used to synthesize the nanoceria for the first time. The method was economical and performed at room temperature. Furthermore, it was coated with gold (Au/nanoceria) and fully characterized using X-ray powder diffraction (XRD), field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (FESEM-EDX), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and zeta potential (ζ potential). The crystallite size obtained from the results was 28.09 nm for Au/nanoceria. The energy-dispersive X-ray spectroscopy (EDX) analysis of Au/nanoceria revealed the compositional constituents of the product, which display the purity of the Au/nanoceria. The cell toxicity properties of the non-doped and Au-coated nanoceria were identified by a MTT analysis on a breast cancer cell line (MCF7). Additionally, human foreskin fibroblast cells (HFF) were used as a normal cell line. The cytotoxicity results indicated that the toxicological effect of Au/nanoceria on cancer cells was significant while having little toxic effect on normal cells. The toxicity effect of nanoceria clearly shows the dependence on dose and time, so, with increasing the dose of Au/nanoceria, the death of cancer cells also increases.

Extracellular biosynthesis, OVAT/statistical optimization, and characterization of silver nanoparticles (AgNPs) using Leclercia adecarboxylata THHM and its antimicrobial activity

BACKGROUND

The biosynthesis of silver nanoparticles (AgNPs) is an area of interest for researchers due to its eco-friendly approach. The use of biological approaches provides a clean and promising alternative process for the synthesis of AgNPs. We used for the first time the supernatant of Leclercia adecarboxylata THHM under optimal conditions to produce AgNPs with an acceptable antimicrobial activity against important clinical pathogens.

RESULTS

In this study, soil bacteria from different locations were isolated and screened for their potential to form AgNPs. The selected isolate, which was found to have the ability to biosynthesize AgNPs, was identified by molecular methods as Leclercia adecarboxylata THHM and its 16S rRNA gene was deposited in GenBank under the accession number OK605882. Different conditions were screened for the maximum production of AgNPs by the selected bacteria. Five independent variables were investigated through optimizations using one variable at a time (OVAT) and the Plackett-Burman experimental design (PBD). The overall optimal parameters for enhancing the biosynthesis of AgNPs using the supernatant of Leclercia adecarboxylata THHM as a novel organism were at an incubation time of 72.0 h, a concentration of 1.5 mM silver nitrate, a temperature of 40.0 °C, a pH of 7.0, and a supernatant concentration of 30% (v/v) under illumination conditions. The biosynthesized AgNPs have been characterized by UV-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR). The biosynthesized AgNPs showed an absorption peak at 423 nm, spherical shape, and an average particle size of 17.43 nm. FTIR shows the bands at 3321.50, 2160.15, and 1636.33 cm^-1 corresponding to the binding vibrations of amine, alkyne nitrile, and primary amine bands, respectively. The biosynthesized AgNPs showed antimicrobial activity against a variety of microbial pathogens of medical importance. Using resazurin-based microtiter dilution, the minimum inhibitory concentration (MIC) values for AgNPs were 500 µg/mL for all microbial pathogens except for Klebsiella pneumoniae ATCC13883, which has a higher MIC value of 1000 µg/mL.

CONCLUSIONS

The obtained data revealed the successful green production of AgNPs using the supernatant of Leclercia adecarboxylata THHM that can be effectively used as an antimicrobial agent against most human pathogenic microbes.

In vitro and in silico studies of silver nanoparticles (AgNPs) from Allium sativum against diabetes

In the present study, the silver nanoparticles (AgNPs) were synthesized from the bulbs of Allium sativum, characterized by UV-visible spectroscopy, FT-IR, SEM, HR-TEM, EDAX analysis and investigated its action on the inhibition of starch digestion. The results proved that the biosynthesized nanoparticles were uniformly dispersed, spherical shaped with the size ranging from 10 to 30 nm. The phytochemical and FT-IR analysis showed the presence of phenols, terpenoids, and amino acids in the synthesized AgNPs. The cytotoxicity analysis revealed that the synthesized AgNPs were non-toxic to the normal cells. The synthesized AgNPs exhibited significant free radical scavenging activity. The in vitro antidiabetic activity showed that the synthesized AgNPs increased glucose utilization, decreased hepatic glucose production, inhibited the activity of starch digestive enzymes such as α-amylase and α-glucosidase, and were not involved in the stimulation of pancreatic cells for the secretion of insulin. The in silico antidiabetic activity analysis (molecular docking) also revealed that the silver atoms of the AgNPs interacted with the amino acid residues of α-amylase, α-glucosidase, and insulin. The present study proved that the AgNPs synthesized from A. sativum have prominent antidiabetic activity in terms of reducing the hyperglycemia through the increased glucose utilization, decreased hepatic glucose production, and the inhibition of α-amylase and α-glucosidase enzymes. So it can be used as a promising nanomedicine for the treatment of diabetes.

Bioinspired Green Synthesis of Silver Nanoparticles Using Three Plant Extracts and Their Antibacterial Activity against Rice Bacterial Leaf Blight Pathogen Xanthomonas oryzae pv. oryzae

Rice bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae (Xoo) is responsible for a significant reduction in rice production. Due to the small impact on the environment, biogenic nanomaterials are regarded as a new type of antibacterial agent. In this research, three colloids of silver nanoparticles (AgNPs) were synthesized with different biological materials such as Arctium lappa fruit, Solanum melongena leaves, and Taraxacum mongolicum leaves, and called Al-AgNPs, Sm-AgNPs and Tm-AgNPs, respectively. The appearance of brown colloids and the UV-Visible spectroscopy analysis proved the successful synthesis of the three colloids of AgNPs. Moreover, FTIR and XRD analysis revealed the formation of AgNPs structure. The SEM and TEM analysis indicated that the average diameters of the three synthesized spherical AgNPs were 20.18 nm, 21.00 nm, and 40.08 nm, respectively. The three botanical AgNPs had the strongest bacteriostatic against Xoo strain C2 at 20 μg/mL with the inhibition zone of 16.5 mm, 14.5 mm, and 12.4 mm, while bacterial numbers in a liquid broth (measured by OD₆₀₀) decreased by 72.10%, 68.19%, and 65.60%, respectively. Results showed that the three AgNPs could inhibit biofilm formation and swarming motility of Xoo. The ultrastructural observation showed that Al-AgNPs adhered to the surface of bacteria and broke the bacteria. Overall, the three synthetic AgNPs could be used to inhibit the pathogen Xoo of rice bacterial leaf blight.

A Critical Review of the Antimicrobial and Antibiofilm Activities of Green-Synthesized Plant-Based Metallic Nanoparticles

Metallic nanoparticles (MNPs) produced by green synthesis using plant extracts have attracted huge interest in the scientific community due to their excellent antibacterial, antifungal and antibiofilm activities. To evaluate these pharmacological properties, several methods or protocols have been successfully developed and implemented. Although these protocols were mostly inspired by the guidelines from national and international regulatory bodies, they suffer from a glaring absence of standardization of the experimental conditions. This situation leads to a lack of reproducibility and comparability of data from different study settings. To minimize these problems, guidelines for the antimicrobial and antibiofilm evaluation of MNPs should be developed by specialists in the field. Being aware of the immensity of the workload and the efforts required to achieve this, we set out to undertake a meticulous literature review of different experimental protocols and laboratory conditions used for the antimicrobial and antibiofilm evaluation of MNPs that could be used as a basis for future guidelines. This review also brings together all the discrepancies resulting from the different experimental designs and emphasizes their impact on the biological activities as well as their interpretation. Finally, the paper proposes a general overview that requires extensive experimental investigations to set the stage for the future development of effective antimicrobial MNPs using green synthesis.

Green synthesis of silver nanoparticles and its antibacterial activity using fungus Talaromyces purpureogenus isolated from Taxus baccata Linn

The present study is focused on the synthesis of silver nanoparticles (AgNPs) utilizing endophytic fungus Talaromyces purpureogenus, isolated from Taxus baccata Linn. Extracellular extract of Talaromyces purpureogenus has shown occurrence of secondary metabolites viz. terpenoids and phenols. Gas chromatography-mass spectroscopy analysis showed the presence of 16 compounds. Techniques like Ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, dynamic light scattering, field emission gun scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction were employed to characterize the synthesized AgNPs. UV–Vis spectroscopy showed sharp peaks at 380–470 nm which indicates the presence of metallic silver. FTIR analysis showed the presence of various functional groups like phenols, hydroxyl groups, and primary amines. In DLS, Z-average size and PdI of synthesized AgNPs were 240.2 r.nm and 0.720 respectively, with zeta potential − 19.6 mV. In FEG-SEM and HRTEM the spherical AgNPs showed diameter in the range of 30–60 nm. In EDS analysis the weight percent of Ag is 67.26% and atomic percent is 43.13%. From XRD analysis the size of AgNPs was found to be 49.3 nm with face-centered cubic crystalline nature of fungal synthesized AgNPs. These nanoparticles have shown significant antibacterial activity against tested strains viz. Listeria monocytogenes (13 ± 0.29 mm), Escherichia coli (17 ± 0.14 mm), Shigella dysenteriae (18 ± 0.21 mm) and Salmonella typhi (14 ± 0.13 mm). These synthesized AgNPs have shown effective free radical scavenging activity against 2,2′-diphenyl-1-picrylhydrazyl. The present study showed that the endophytic fungus Talaromyces purpureogenus can be used as a prominent source to synthesize AgNPs by using biological, ecofriendly, and in a non-toxic way accompanied by antibacterial and antioxidant properties which further can reduce the harvesting pressure faced by Taxus baccata.

Graphical Abstract

Biosynthesis and characterisation of solid lipid nanoparticles and investigation of toxicity against breast cancer cell line

Solid lipid nanoparticles (SLNs) comprise non-toxic surface-active lipidic agents combined with appropriate ratios of drugs or essential oils. The goal of this research was to investigate the effects of the SLN synthesised using essential oils of Foeniculum vulgare on the MCF-7 breast cancer cell line. SLNs were prepared by homogenisation and ultrasound techniques and characterised by dynamic light scattering (DLS), zeta potential assessment, and transmission electron microscopy (TEM). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay (MTT assay), flow-cytometry, and Acridine-Orange assay were employed for assessing the biological activities of the SLNs. The average particle size was 55.43 nm and the net surface charge was -29.54 ± 11.67 mV. TEM showed that the mean particle size was 33.55 nm and the synthesised SLNs had a uniform round morphology. The MTT assay showed that the prepared SLNs had high toxicity against MCF-7 cells and low toxicity against normal HUVECs cells. Flow-cytometry revealed a noteworthy rise in the subG1 peak of the cell cycle in the cancer cells treated with SLNs compared to the controls, indicating apoptosis in cancer cells. The results also showed discolouration in SLNs-treated cells, which further confirmed the induction of apoptosis and the toxicity of the SLNs against MCF-7 cells.

Application of Response Surface Methodology for Optimizing the Therapeutic Activity of ZnO Nanoparticles Biosynthesized from Aspergillus niger

In this study, the biosynthesis of zinc oxide nanoparticles using Aspergillus niger (A/ZnO-NPs) is described. These particles have been characterized by UV-Vis spectrum analysis, X-ray powder diffraction, field emission scanning electron microscopy, and transmission electron microscopy. To use this biosynthesized nanoparticle as an antiproliferative and antimicrobial agent, the IC₅₀ value against the breast cancer cell line and inhibition zone against Escherichia coli were used to optimize the effect of two processing factors including dose of filtrate fungi cell and temperature. The biosynthesized A/ZnO-NPs had an absorbance band at 320 nm and spherical shapes. The mean particles size was 35 nm. RSM (response surface methodology) was utilized to investigate the outcome responses. The Model F-value of 12.21 and 7.29 implies that the model was significant for both responses. The contour plot against inhibition zone for temperature and dose showed that if the dose increases from 3.8 to 17.2 µg/mL, the inhibition zone increases up to 35 mm. As an alternative to chemical and/or physical methods, biosynthesizing zinc oxide NPs through fungi extracts can serve as a more facile and eco-friendly strategy. Additionally, for optimization of the processes, the outcome responses in the biomedical available test can be used in the synthesis of ZnO-NPs that are utilized for large-scale production in various medical applications.

Stem cell therapy in the heart: Biomaterials as a key route

Cardiovascular diseases are one of the main concerns, nowadays causing a high rate of mortality in the world. The majority of conventional treatment protects the heart from failure progression. As a novel therapeutic way, Regenerative medicine in the heart includes cellular and noncellular approaches. Despite the irrefutable privileges of noncellular aspects such as administration of exosomes, utilizing of miRNAs, and growth factors, they cannot reverse necrotic or ischemic myocardium, hence recruiting of stem cells to help regenerative therapy in the heart seems indispensable. Stem cell lineages are varied and divided into two main groups namely pluripotent and adult stem cells. Not only has each of which own regenerative capacity, benefits, and drawbacks, but their turnover also close correlates with the target organ and/or tissue as well as the stage and level of failure. In addition to inefficient tissue integration due to the defects in delivering methods and poor retention of transplanted cells, the complexity of the heart and its movement also make more rigorous the repair process. Hence, utilizing biomaterials can make a key route to tackle such obstacles. In this review, we evaluate some natural products which can help stem cells in regenerative medicine of the cardiovascular system.

Assessment of Antioxidant and Antimicrobial Activities of Silver Nanoparticles Biosynthesized by Haplophyllum Obtusifolium

Background: Plants comprise great antioxidant sources as a result of their redox and biochemical components, which are rich in secondary metabolites such as phenolic acids, flavonoids, and other constituents. Haplophyllum obtusifolium from polygonaceae is widely used for preventing and managing diabetes. This study investigated the antibacterial and antioxidant activities of silver nanoparticles (AgNPs) biosynthesized by H. obtusifolium. Methods: The aerial parts of H. obtusifolium were gathered from the north of Khorasan Razavi province, Iran and desiccated at the chamber temperature. The shoots were powdered by grinding, 5 g of the powder was mixed with 250 mL of deionized water, and the resultant blend was then filtered. Bactericidal properties and antioxidant activity of the nanoparticles were assessed using disk diffusion and DPPH (2, 2-diphenyl-1-picrylhydrazyl) tests, respectively. Results: The results of this study showed that the biosynthesized nanoparticles exhibited antibacterial activity against a gram-negative (Klebsiella pneumoniae) bacterium, but they had no effects on gram-positive Staphylococcus epidermidis. Antioxidant test results showed that these nanoparticles were capable of eliminating DPPH radicals in a concentration-dependent manner so that a more potent antioxidant activity was seen in higher concentrations of the nanoparticles. Conclusion: Our results suggested that H. obtusifolium can be used as a key source of antioxidants/ antimicrobial agents in food and pharmaceutical industries.

Characterization of silver nanoparticles biosynthesized using Amaranthus cruentus

The use of plant extracts is a low-cost and green way to synthesize nanoparticles. In this research, the authors investigated the antibacterial, cytotoxic and antiangiogenic properties of silver nanoparticles (AgNPs) synthesized using Amaranthus cruentus extract. The fabricated nanoparticles were characterized by transmission electron microscopy (TEM), field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, dynamic light scattering and X-ray diffraction. The TEM results showed that the typical size of the AgNPs recorded was 15 nm. Biological tests indicated that the biosynthesized AgNPs had caused a decrease in cancerous cells (MCF-7) and had a high antibacterial activity against Escherichia coli, Staphylococcus epidermidis and Staphylococcus aureus. According to data analysis, the number and length of the blood vessels in different concentrations of AgNPs reduced significantly (depending on the dose). The chorioallantoic membrane assay revealed a large decrease in the number and length of angiogenic blood vessels in the presence of AgNPs. Real-time polymerase chain reaction and flow cytometry studies showed a dramatic increase in the gene expression of caspase-3 and caspase-8.

Modulatory effects of Cornus sanguinea L. mediated green synthesized silver nanoparticles on oxidative stress, COX-2/NOS2 and NFkB/pNFkB expressions in experimental inflammation in Wistar rats

The present study presents a green, cost efficient and easy synthesis method of silver nanoparticles (AgNPs) using an aqueous extract of Cornus sanguinea L. fruits (CS). The phytosynthesized silver nanoparticles were characterized using various analytical techniques such as UV-Vis absorption spectroscopy, which confirmed the formation of AgNPs and FTIR spectroscopy, in order to certify the role of the biomolecules present in the fruit extract as reducing and capping agents of the AgNPs. The UV-Vis absorption spectrum showed a broad band at 407 nm characteristic for colloidal silver. Transmission electron microscopy was conducted to investigate the shape and size of the silver nanoparticles, revealing a spherical shape with an average particle size of 18 nm. The antioxidant and anti-inflammatory activities of the fruit extract and green synthesized silver nanoparticles were assessed in vivo on experimental inflammation. The obtained results showed that CS and AgNPs reduced oxidative stress in parallel with increasing of antioxidant defense and diminished the COX-2 expressions. CS extract had a dual effect on NFkB activation depending on the time of testing while AgNPs increased NFkB phosphorylation at 48 h. These results suggested that both AgNPs and CS extract exhibited antioxidant and anti-inflammatory activities but with a different dynamics of action.

Cardiovascular effects of standardized hydroalcoholic extract of Ribes khorasanicum fruit in acute hypertensive rats

OBJECTIVE

Ribes khorasanicum (R. khorasanicum) traditionally has been used for the treatment of higher blood pressure. In this study, the effect of hydroalcoholic extract of R. khorasanicum fruit in normotensive and hypertensive rats was evaluated.

MATERIALS AND METHODS

Animals were assigned into the following groups: 1) Control, 2) AngII (50 ng/kg), 3) AngII + losartan (Los, 10 mg/kg) and 4-6) Doses 4, 12 and 24 mg/kg of extract +AngII groups. AngII and Los were injected intravenously and the extract was injected intraperitoneal. In R. khorasanicum groups, AngII injected 30 after injection of the extract. The femoral artery was cannulated and mean arterial pressure (MAP), systolic blood pressure (SBP), and heart rate (HR) were recorded by Power Lab software. Maximal changes (∆) of cardiovascular responses were determined and compared with those of control and AngII groups. Finally, oxidative stress parameters in the heart and aorta were also determined.

RESULTS

In normotensive rats, 12 mg/kg of the extract showed significant hypotensive effects while 24 mg/kg produced significant tachycardia. Increased ∆SBP and ∆MAP in AngII group were significantly blunted by Los. Doses 4 and 12 mg/kg of the plant also significantly attenuate the effect of AngII on ∆SBP and ∆MAP. Tachycardia induced by 24 mg/kg of the extract didn't affect by AngII. Extract also significantly improved the effect of AngII on MDA, total thiol content, CAT and SOD in both heart and aorta tissues.

CONCLUSION

R. khorasanicum at lower doses showed hypotensive effects and attenuated cardiovascular parameters in hypertensive rats via its antioxidant effects.

The Anti-oxidant and Anti-inflammatory Properties of Cerium Oxide Nanoparticles Synthesized Using Origanum majorana L. Leaf Extract

Introduction: Free radicals have singlet electron in their outer layer rendering them high reactivity against biomolecules (i.e., DNA, carbohydrates, proteins, and lipids). Oxidative stress is created when the production of free radicals exceeds their removal by antioxidant systems and is involved in the pathogenesis of several diseases such as diabetes, arthritis, inflammatory conditions, and various cancers. Regarding the therapeutic potential of nanoparticles (NPs) in human diseases, the purpose of this study was to synthesize cerium oxide NPs using Origanum majorana leaf extract. Methods: Cerium oxide nanoparticles (CeO2 -NPs) were synthesized using aqueous leaf extract of O. majorana. The sizes of NPs were characterized by a particle size analyzer. The antioxidant properties of the CeO2 -NPs were determined by Ferric-reducing antioxidant power (FRAP) assay. The anti-inflammatory effects of the NPs were also determined by measuring gene expressions of IL-1β and IL-10 using real-time polymerase chain reaction (PCR). Results: The CeO2 -NPs were successfully synthesized using O. majorana leaf extract. The results of FRAP assay showed that the anti-oxidant activities of CeO2 -NPs at concentrations of 50, 100, and 400 μg/mL were 75%, 77.1%, and 94.5%, respectively. Moreover, interleukin 10 (IL-10) gene expressions increased by 4.6 folds while the expression of IL-1β gene decreased by 0.75-fold in HUVECs. Conclusion: The CeO2 -NPs synthesized using the aqueous extract of O. majorana demonstrated antioxidant and anti-inflammatory properties. Therefore, these NPs can be used as potential therapeutic agents in medicine.

The Expression of Antioxidant Genes and Cytotoxicity of Biosynthesized Cerium Oxide Nanoparticles Against Hepatic Carcinoma Cell Line

Background: Drug resistance due to genetic variations renders many therapeutic methods such as surgery, radiotherapy, chemotherapy, and hormone therapy unsuccessful in eradicating cancerous cells. Nowadays, application of nanoparticles (NPs) has been promising in destroying cancerous cells without side effects on normal cells. Objectives: This study aimed to investigate the antioxidant and anticancer effects of biosynthesized cerium oxide nanoparticles (CeO2 -NPs) on a hepatic carcinoma cell line. Methods: MTT assay was used to determine the cytotoxicity of CeO2 -NPs in concentrations of 0, 15.6, 31.2, 62.5, 125, and 250 μg/mL after 24, 48, and 72 hours of incubation. Moreover, the expression levels of catalase (CAT) and superoxide dismutase (SOD) (the antioxidant genes) were investigated at different concentrations of CeO2 -NPs using real-time polymerase chain reaction (PCR). Results: Our results showed a significant toxicity of the synthesized NPs against the cancerous liver cells. The IC50 calculated for CeO2 -NPs was 500 μg/mL at 24 hours of incubation. In addition, the expression levels of CAT and SOD significantly (P<0.05) increased upon the treatment of cells with CeO2 -NPs (500 µg /mL) compared to the untreated cells. Conclusion: Considering the minimal effects of the biosynthesized CeO2 -NPs on normal cells and on the other hand their considerable toxicity against hepatic cancer cells, these NPs could be utilized in medicine and in the development of new drugs for cancer cells.