Muhammad Ovais

Green synthesis of silver nanoparticles using Alysicarpus monilifer leaf extract and its antibacterial activity against MRSA and CoNS isolates in HIV patients

The emergence of multi‐drug‐resistant microorganisms in hospital environments is a global public health problem and threat to everyone, especially HIV‐infected patients. Methicillin‐resistant Staphylococcus aureus (MRSA) and coagulase‐negative Staphylococci (CoNS) are the major causative agents associated with morbidity and mortality in HIV patients. Therefore, control of MRSA and CoNS‐related infections in HIV patients is a worldwide concern. To investigate novel, potent, and cost‐effective therapeutic approaches, the current study reports a simple and rapid synthesis of silver nanoparticles (AgNPs) using aqueous leaf extract of Alysicarpus monilifer and its antibacterial efficacy against multi‐drug‐resistant MRSA and CoNS isolates from HIV patients. The green‐synthesized AgNPs were characterized using ultraviolet‐visible spectroscopy, transmission electron microscopy, energy dispersive X‐ray analysis, selected area electron diffraction pattern, X‐ray diffraction patterns, and Fourier transform infrared spectroscopy. Stable, well‐defined AgNPs, mostly spherical in shape with mean size of 15 ± 2 nm, were obtained within an hour. Moreover, green synthesized AgNPs revealed significant dose‐dependent antibacterial action against MRSA and CoNS isolates. This study concludes that biogenic AgNPs have demonstrated to be potent antibacterial agents in comparison with conventional antibiotics.

Biomimetic synthesis of silver nanoparticles from Streptomyces atrovirens and their potential anticancer activity against human breast cancer cells

Silver nanoparticles (AgNPs) have been undeniable for its antimicrobial activity while its antitumour potential is still limited. Therefore, the present study focused on determining cytotoxic effects of AgNPs on Michigan cancer foundation-7 (MCF-7) breast cancer cells and its corresponding mechanism of cell death. Herein, the authors developed a bio-reduction method for AgNPs synthesis using actinomycetes isolated from marine soil sample. The isolated strain was identified by 16s ribotyping method and it was found to be Streptomyces atrovirens. Furthermore, the synthesised AgNPs were characterised by various bio-analytical techniques such as ultraviolet-visible spectrophotometer, atomic force microscopy, transmission electron microscopy, Fourier transform infra-red spectroscopy, and X-ray diffraction. Moreover, the results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay reveals 44.51 µg of AgNPs to have profound inhibition of cancer cell growth; furthermore, the inhibition of MCF-7 breast cancer cell line was found to be dose dependent on treatment with AgNPs. Acridine orange and ethidium bromide double staining methods were performed for cell morphological analysis. The present results showed that biosynthesised AgNPs might be emerging alternative biomaterials for human breast cancer therapy.

Anti-cancer green bionanomaterials: present status and future prospects

ABSTRACT Cancer is one of the most common health problems responsible for outnumbered deaths worldwide. Nanomedicine plays an important role in developing alternative and more effective treatment strategies for cancer theranostics. However, the toxicity, high cost and nanoparticles (NPs) production complexity are some of the major issues that obstruct the use of existing nanomedicine. Recently, the green synthesis of biogenic NPs from plants and microbial sources has become an emerging field due to their safer, eco-friendly, simple, fast, energy efficient, low-cost and less toxic nature. Interestingly, NPs play a key role in diagnosis of tumor at the initial stage by allowing cellular visualization. Furthermore, prospective applications of green NPs include magnetically responsive drug delivery, anti-cancer activity, photo-thermal therapy and bio-imaging. The present review provides perspective on the use of anti-cancer green bionanomaterials with a focus on their present status and future prospects in the theranostics of cancer. GRAPHICAL ABSTRACT

Sageretia thea (Osbeck.) mediated synthesis of zinc oxide nanoparticles and its biological applications

AIM To investigate the physical and biological properties of bioinspired zinc oxide (ZnO) nanoparticles via aqueous leaf extracts of Sageretia thea. EXPERIMENTAL Nanoparticles of size approximately 12.4 nm were extensively characterized. In vitro antimicrobial, cytotoxic, biocompatible and enzyme inhibition assays were performed. RESULTS Significant antimicrobial activities with and without UV illumination are reported. Bioinspired ZnO nanoparticles were found effective against fungal strains. MTT assay was performed to check the leishmanicidal activity against promastigotes (IC50: 6.2 μg/ml) and amastigotes (IC50: 10.87 μg/ml) of Leishmania tropica. Brine shrimp lethality was also indicated by bioinspired ZnO nanoparticles (IC50: 21.29 μg/ml). CONCLUSION Hemocompatible nature of bioinspired nanoparticles was revealed. Furthermore, the antioxidant activities were performed. In addition, significant protein kinase while insignificant alpha amylase inhibition were recorded.

Biosynthesis of iron oxide (Fe2O3) nanoparticles via aqueous extracts of Sageretia thea (Osbeck.) and their pharmacognostic properties

ABSTRACT Sageretia thea (Osbeck.) was used as an effective chelating agent for the biosynthesis of iron oxide nanoparticles (IONPs) and extensively characterized through XRD, FTIR, Raman spectroscopy, Energy Dispersive Spectroscopy, HR-SEM/TEM and SAED. Antibacterial assays against five human pathogenic bacterial strains were carried out and minimum inhibitory concentrations were calculated. Pseudomonas aeruginosa (MIC: 7.4 µg/mL) was the most susceptible strain to biosynthesized IONPs. All of the fungal strains showed susceptibility to the IONPs. MTT cytotoxic assay was carried out against the promastigote and amastigote cultures of Leishmania tropica and their IC50 values were calculated as 17.2 and 16.75 µg/mL. The cytotoxic potential was further assessed using brine shrimps, and the IC50 was calculated as 16.46 µg/mL. Moderate antioxidant activities were reported. Human RBCs and macrophages were found to be biocompatible with biogenic IONPs (IC50 > 200 µg/mL). GRAPHICAL ABSTRACT

Anti-Alzheimer’s Studies on β-Sitosterol Isolated from Polygonum hydropiper L.

The family Polygonaceae is known for its traditional use in the management of various neurological disorders including Alzheimer’s disease (AD). In search of new anti-AD drugs, β-sitosterol isolated from Polygonum hydropiper was subjected to in vitro, in vivo, behavioral and molecular docking studies to confirm its possibility as a potential anti-Alzheimer’s agent. The in vitro AChE, BChE inhibitory potentials of β-sitosterol were investigated following Ellman’s assay. The antioxidant activity was tested using DPPH, ABTS and H2O2 assays. Behavioral studies were performed on a sub-strain of transgenic mice using shallow water maze (SWM), Y-maze and balance beam tests. β-sitosterol was tested for in vivo inhibitory potentials against cholinesterase’s and free radicals in the frontal cortex (FC) and hippocampus (HC). The molecular docking study was performed to predict the binding mode of β-sitosterol in the active sites of AChE and BChE as inhibitor. Considerable in vitro and in vivo cholinesterase inhibitory effects were observed in the β-sitosterol treated groups. β-sitosterol exhibited an IC50 value of 55 and 50 μg/ml against AChE and BChE respectively. Whereas, the activity of these enzymes were significantly low in FC and HC homogenates of transgenic animals. Molecular docking studies also support the binding of β-sitosterol with the target enzyme and further support the in vitro and in vivo results. In the antioxidant assays, the IC50 values were observed as 140, 120, and 280 μg/ml in the DPPH, ABTS and H2O2 assays respectively. The free radicals load in the brain tissues was significantly declined in the β-sitosterol treated animals as compared to the transgenic-saline treated groups. In the memory assessment and coordination tasks including SWM, Y-maze and balance beam tests, β-sitosterol treated transgenic animals showed gradual improvement in working memory, spontaneous alternation behavior and motor coordination. These results conclude that β-sitosterol is a potential compound for the management of memory deficit disorders like AD.

Sageretia thea (Osbeck.) modulated biosynthesis of NiO nanoparticles and their in vitro pharmacognostic, antioxidant and cytotoxic potential

Abstract NiO nanoparticles are biosynthesized using Sageretia thea (Osbeck.) aqueous leave extracts and their biological activities are reported. Nanoparticles (∼18 nm) were characterized through XRD, ATR-FTIR, EDS, SAED, HR-SEM/TEM and Raman spectroscopy. Antibacterial activity was investigated against six pathogenic bacterial strains (gram positive and gram negative) and their corresponding minimum inhibitory concentrations (MICs) were calculated. UV-exposed nanoparticles were investigated to have reduced MICs relative to the NiO nanoparticles have not been exposed to UV. Moderate linear fungal growth inhibition was observed while Mucor racemosus (percentage inhibition 64% ± 2.30) was found to be most susceptible. Cytotoxicity was confirmed using brine shrimps lethality assay (IC50 42.60 μg/ml). MTT cytotoxicity was performed against Leishmania tropica-KWH23 promastigotes and amastigotes revealed significant percentage inhibition across the applied concentrations. IC50 values were calculated as 24.13 μg/ml and 26.74 μg/ml for the promastigote and amastigote cultures of Leishmania tropica. NiO nanoparticles were found. Moderate, antioxidant potential was concluded through assays like DPPH, TAP and TAC. Furthermore, protein kinase inhibition and alpha amylase inhibition is also reported. Graphical Abstract

Selected hepatoprotective herbal medicines: Evidence from ethnomedicinal applications, animal models, and possible mechanism of actions

Insight into the hepatoprotective effects of medicinally important plants is important, both for physicians and researchers. Main reasons for the use of herbal medicine include their lesser cost compared with conventional drugs, lesser undesirable drug reactions and thus high safety, and reduced side effects. The present review focuses on the composition, pharmacology, and results of experimental trials of selected medicinal plants: Silybum marianum (L.) Gaertn., Glycyrrhiza glabra, Phyllanthus amarus Schumach. & Thonn., Salvia miltiorrhiza Bunge., Astragalus membranaceus (Fisch.) Bunge, Capparis spinosa (L.), Cichorium intybus (L.), Solanum nigrum (L.), Sapindus mukorossi Gaertn., Ginkgo biloba (L.), Woodfordia fruticosa (L.) Kurz, Vitex trifolia (L.), Schisandra chinensis (Turcz.) Baill., Cuscuta chinensis (Lam.), Lycium barbarum, Angelica sinensis (Oliv.) Diels, and Litsea coreana (H. Lev.). The probable modes of action of these plants include immunomodulation, stimulation of hepatic DNA synthesis, simulation of superoxide dismutase and glutathione reductase to inhibit oxidation in hepatocytes, reduction of intracellular reactive oxygen species by enhancing levels of antioxidants, suppression of ethanol‐induced lipid accumulation, inhibition of nucleic acid polymerases to downregulate viral mRNA transcription and translation, free radical scavenging and reduction of hepatic fibrosis by decreasing the levels of transforming growth factor beta‐1, and collagen synthesis in hepatic cells. However, further research is needed to identify, characterize, and standardize the active ingredients, useful compounds, and their preparations for the treatment of liver diseases.

Advances in nano-delivery systems for doxorubicin: an updated insight

Abstract Doxorubicin (DOX) is the most effective chemotherapeutic drug developed against broad range of cancers such as solid tumours, transplantable leukemias and lymphomas. Conventional DOX-induced cardiotoxicity has limited its use. FDA approved drugs i.e. non-pegylated liposomal (Myocet®) and pegylated liposomal (Doxil®) formulations have no doubt shown comparatively reduced cardiotoxicity, but has raised new toxicity issues. The entrapment of DOX in biocompatible, biodegradable and safe nano delivery systems can prevent its degradation in circulation minimising its toxicity with increased half-life, enhanced pharmacokinetic profile leading to improved patient compliance. In addition, nano delivery systems can actively and passively target the tumour resulting increase in therapeutic index and decreased side effects of drug. Foreseeing the need of a comprehensive review on DOX nanoformulations, in this article we for the first time have given an updated insight on DOX nano delivery systems.

The efficacy of green nanoparticles against cancerous and normal cell lines: A systematic review and meta-analysis

This study aimed to perform a systematic review and meta-analysis of papers discussing the efficacy of microbial synthesised metallic nanoparticles (MNPs) against cancerous and normal cell lines by exploiting Bayesian generalised linear (BGL) model. Data was systematically collected from published papers via Cochrane library, Web of Science, PubMed, Science Direct, ProQuest, Scopus, and Embase. Impressively, most of the studies were carried out on HeLa and A549 cancer cell lines. Specifically, a hefty 65.67% of studies employed bacteria to biofabricate MNPs. Significantly, BGL meta-analysis represented highly valuable information. Hence, based on adjusted analysis, the MNPs with the size of 25-50 nm were found to be far less cytotoxic than the MNPs with the size of ≤25 nm (OR = 0.233, P ˂ 0.05) against either cancerous or normal cell lines. Interestingly, it was found that the odds of cytotoxicity in cancerous cell lines were practically nine times more than normal cell lines, representing the substantially more cytotoxicity of MNPs in cancerous cell lines (OR = 9.004, P ˂ 0.001). Green MNPs mentioned here may be developed as novel anti-cancer agents, which could lead to a revolution in the treatment of cancer.