Valorization and Repurposing of Citrus limetta Fruit Waste for Fabrication of Multifunctional AgNPs and Their Diverse Nanomedicinal Applications.

Herein we propose an ecofriendly process for the biofabrication of AgNPs by applying fruit waste of Citrus limetta. The aqueous extracts from the peels of the fruit were used as green chelating and stabilizing agents. Structural, optical, vibrational, morphological, and magnetic properties were established using UV-Vis (ultraviolet visible spectroscopy), XRD (X-rays diffraction), FTIR (Fourier transformed infrared spectroscopy), EDS (energy dispersive spectroscopy), SEM (scanning electron microscopy), ESR (electron spin resonance), and PPMS (physical property management system), while the thermal properties were established using TGA/DTG (thermal gravimetric analysis/derivative thermogravimetry). XRD pattern revealed intense peaks with single-phase purity, while the Debye-Scherrer approximation revealed an average crystallite size of 33.18 nm. The W-H plot revealed the size of 55.2 nm and strain 2.68 × 10-4. FTIR spectra revealed the involvement of different functional groups and major IR vibrations were observed at 2329 cm-1, 2092 cm-1, 1794 cm-1, 1268 cm-1, and 754 cm-1. TGA/DTG revealed major weight loss events at 240 °C and 360 °C. SEM revealed spherical or quasi-spherical morphology, while EDS confirmed the presence of elemental silver. The M-H behavior for all measurement temperature shows diamagnetic behavior. Electron spin resonance (ESR) revealed a high proportion of free electrons. Furthermore, the pharmacognostic and nanomedicinal potential CL-AgNPs was established using multiple in vitro and in vivo bioassays. The in vivo wound healing assays in mice revealed excellent healing potential which were similar to positive control. The percent wound healing is reported to be 93% on the 14th day of incision after application of CL-AgNPs. Bioassays were performed to assess enzyme inhibition potential of the CL-AgNPs for Alzheimer disease and antidiabetic applications. The AChE and BChE potential of the CL-AgNPs was highest at 1000 µg mL-1, i.e., 92% and 56%, respectively. The α-glucosidase inhibition potential for the CL-AgNPs was higher as compared to the α-glucosidase, while the DPPH free radical scavenging was reported to be 70% to 11% at varying concentrations between 1000 and 62.5 µg mL-1. Overall, our results indicate that the waste fruit peels can be a sustainable and eco-friendly resource of synthesis of the multifunctional nanoparticles.

Green Nano-Biotechnology: A New Sustainable Paradigm to Control Dengue Infection.

Dengue is a growing mosquito-borne viral disease prevalent in 128 countries, while 3.9 billion people are at high risk of acquiring the infection. With no specific treatment available, the only way to mitigate the risk of dengue infection is through controlling of vector, i.e., Aedes aegypti. Nanotechnology-based prevention strategies like biopesticides with nanoformulation are now getting popular for preventing dengue fever. Metal nanoparticles (NPs) synthesized by an eco-friendly process, through extracts of medicinal plants have indicated potential anti-dengue applications. Green synthesis of metal NPs is simple, cost-effective, and devoid of hazardous wastes. The recent progress in the phyto-synthesized multifunctional metal NPs for anti-dengue applications has encouraged us to review the available literature and mechanistic aspects of the dengue control using green-synthesized NPs. Furthermore, the molecular bases of the viral inhibition through NPs and the nontarget impacts or hazards with reference to the environmental integrity are discussed in depth. Till date, major focus has been on green synthesis of silver and gold NPs, which need further extension to other innovative composite nanomaterials. Further detailed mechanistic studies are required to critically evaluate the mechanistic insights during the synthesis of the biogenic NPs. Likewise, detailed analysis of the toxicological aspects of NPs and their long-term impact in the environment should be critically assessed.

Extraction optimization, Total Phenolic-Flavonoids content, HPLC-DAD finger printing, antimicrobial, antioxidant and cytotoxic potentials of Chinese folklore Ephedra intermedia Schrenk & C. A. Mey

Abstract Plants from genus Ephedra are commonly used by the Chinese people as folk medicine for treatment of various diseases. The current study was designed to explore the ethno-pharmacological based pharmacological potentials of Ephedra intermedia Schrenk & C.A. Mey. (E. intermedia). Plant aerial parts were extracted using ten solvent systems with increasing order of polarity. Samples were analyzed for total phenolic and flavonoid contents, HPLC-DAD analysis, antibacterial, antifungal, HepG2 cell line cytotoxicity, hemolysis and antioxidant potentials following standard procedures. Highest percent extract recovery was observed in Eth+WT (25.55 % w/w) solvent system. Flavonoid and phenolic contents were higher in chloroform and Met+WT fractions respectively. Considerable antibacterial activity was shown by Eth+Met extract against B. subtilis and K. pneumonia (MIC of 11.1μg/mL for each). Eth extract exhibited high antifungal activity against A. fumigates (15±0.31 mm DIZ). Met+WT extract showed significant cytotoxicity against HepG2 cell lines with IC50 of 13.51+0.69 μg/mL. Substantial free radical scavenging activity (74.9%) was observed for Met+Eth extract. In the current study, several solvent systems were used for more effective extraction of fractions and can be useful in the isolation of phytochemicals. Various fractions exhibited considerable antimicrobial, antioxidant and cytotoxic potentials. Biological potentials of E. intermedia signify its potential uses in microbial, cancer and degenerative disorders and thus warrant further detailed studies.

Precursor effects on the physical, biological, and catalytic properties of Fagonia indica Burm.f. mediated zinc oxide nanoparticles.

We report a facile, green and precursor-based comparative study on the biosynthesis of zinc oxide (ZnO) nanoparticles (NPs) using anticancerous Fagonia indica as effective chelating agent. Biosynthesis was carried out using zinc sulfate and zinc acetate as precursor salts to make ZnOS and ZnOA NPs under similar experimental conditions which were characterized extensively for physical and biological properties. Scherrer equation deduced a mean crystallite size of ~23.4 nm for ZnOA NPs and ~41 nm for ZnOS NPs. The nature of the NPs was compared using UV, diffuse reflectance spectra, Fourier transform infrared spectroscopy, thermogravimetric analysis-DTA, selected area electron diffraction, EDS, zeta potential, high resolution (HR)-SEM, and HR-TEM. Detailed in vitro pharmacognostic activities revealed a significant therapeutic potential for ZnOA and ZnOS . Potential antimicrobial activities for the NPs and their nanocosmeceutical formulations are reported. ZnOA NPs were more cytotoxic to Leishmania tropica as compared to ZnOS . Significant antioxidant and protein kinase inhibition was obtained. The hemolytic assay indicated a hemocompatible nature of both ZnOA and ZnOS NPs. Catalytic degradation of crystal violet dye (CVD) by NPs was examined under different parameters (light, dark, UV). Furthermore, sonophotocatalytic degradation of CVD was also studied. Our results suggested that precursor can have a significant effect on the physical, biological, and catalytic properties of the NPs. In future, we recommend different other in vitro, in vivo biological activities, and mechanistic studies of these as-synthesized NPs.

Silver nanoparticles biosynthesized from secondary metabolite producing marine actinobacteria and evaluation of their biomedical potential.

Biosynthesis of silver nanoparticles (AgNPs) from marine actinobacteria offers a promising avenue for exploring bacterial extracts as reducing and stabilizing agents. We report extracellular extracts of Rhodococcus rhodochrous (MOSEL-ME29) and Streptomyces sp. (MOSEL-ME28), identified by 16S rRNA gene sequencing for synthesis of AgNPs. Ultrafine silver nanoparticles were biosynthesized using the extracts of R. rhodochrous and Streptomyces sp. and their possible therapeutic applications were studied. The physicochemical properties of nanoparticles were established by HR-SEM/TEM, SAED, UV-Vis, EDS, XRD, and FTIR. UV-Vis spectra displayed characteristic absorption at 430 nm and 412 nm for AgNPs from Streptomyces sp. (S-AgNPs) and Rhodococcus sp. (R-AgNPs), respectively. HR-SEM/TEM, XRD, EDS analysis confirmed the spherical shape, crystalline nature, and elemental formation of silver. Crystallite or grain size was deduced as 5.52 nm for R-AgNPs and 35 nm for S-AgNPs. Zeta-potential indicated electrostatic negative charge for AgNPs, while FTIR revealed the presence of diverse functional groups. Disc diffusion assay indicated the broad-spectrum antibacterial potential of S-AgNPs with the maximum inhibition of B. subtilis while R-AgNPs revealed potency against P. aeruginosa at 10 µg/mL concentration. Biogenic AgNPs revealed antileishmanial activity and the IC50 was calculated as 164 µg/mL and 184 µg/mL for R-AgNPs and S-AgNPs respectively. Similarly, the R-AgNPs and S-AgNPs revealed anti-cancer potential against HepG2 and the IC50 was calculated as 49 µg/mL and 69 µg/mL for R-AgNPs and S-AgNPs, respectively. Moreover, the antioxidant activity showed significant results. MTT assay on RD cells, L20B cells, and Hep-2C indicated intensification in viability by reducing the concentration of R-AgNPs and S-AgNPs. The R-AgNPs and S-AgNPs inhibited sabin-like poliovirus (1TCID50 infection in RD cells). Furthermore, hemocompatibility at low concentrations has been confirmed. Hence, it is concluded that biogenic-AgNPs has the potential to be used in diverse biological applications and that the marine actinobacteria are an excellent resource for fabrication of AgNPs.

Floral extracts-mediated green synthesis of NiO nanoparticles and their diverse pharmacological evaluations.

Biosynthesis has emerged as an exciting interface for assembling multifunctional metal oxide nanoparticles for diverse medicinal applications. Herein, biogenic nickel oxide (NiO-NPs) is synthesized by using floral extracts of Callistemon viminalis (C. viminalis) as a low cost, ecofriendly reducing and stabilizing agent. NiO-NPs were annealed at 300 °C, 400 °C and 500 °C while their physiochemical properties were established by HR-SEM/TEM, UV, XRD, FTIR, EDS, SAED and SQUID techniques. Particle size of NiO-NPs decreased with increase in annealing temperatures. Magnetization curves indicated superparamagnetic behavior of the biogenic NiO-NPs at 300 K. Highly crystalline NiO-NPs obtained after annealing at 500 °C were used for biomedical applications. The anti-leishmanial activity on Leishmania tropica promastigotes (KMH-23) and anticancer activity on HepG2 (RCB1648) revealed excellent inhibition potential with IC50 of 37.21 µg/mL and 47 µg/mL, respectively. Significant antibacterial effect was observed against Klebsiella pneumonia and Proteus vulgaris with MIC's of 12.5 µg/mL each. Acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and α-glucosidase inhibitory potential were comparable with positive control drugs. Moderate antioxidant activities were observed. NiO-NPs were observed to be hemolytic (30%) at higher dose (1000 µg/mL). Overall, NiO-NPs revealed a multifunctional nature that can be explored for diverse biomedical applications.Communicated by Ramaswamy H. Sarma.

Green-Synthesized Silver Nanoparticles Induced Apoptotic Cell Death in MCF-7 Breast Cancer Cells by Generating Reactive Oxygen Species and Activating Caspase 3 and 9 Enzyme Activities.

Silver nanoparticles are among the most significant diagnostic and therapeutic agents in the field of nanomedicines. In the current study, the green chemistry approach was made to optimize a cost-effective synthesis protocol for silver nanoparticles from the aqueous extract of the important anticancer plant Fagonia indica. We investigated the anticancer potential and possible involvement of AgNPs in apoptosis. The biosynthesized AgNPs are stable (zeta potential, -16.3 mV) and spherical with a crystal size range from 10 to 60 nm. The MTT cell viability assay shows concentration-dependent inhibition of the growth of Michigan Cancer Foundation-7 (MCF-7) cells (IC50, 12.35 µg/mL). In addition, the fluorescent microscopic analysis shows activation of caspases 3 and 9 by AgNPs that cause morphological changes (AO/EB assay) in the cell membrane and cause nuclear condensation (DAPI assay) that eventually lead to apoptotic cell death (Annexin V/PI assay). It was also observed that AgNPs generate reactive oxygen species (ROS) that modulate oxidative stress in MCF-7 cells. This is the first study that reports the synthesis of a silver nanoparticle mediated by Fagonia indica extract and evaluation of the cellular and molecular mechanism of apoptosis.

Phyto-fabricated Cr2O3 nanoparticle for multifunctional biomedical applications.

Aim: The biosynthesis of chromium oxide nanoparticles (Cr2O3 NPs), using Hyphaene thebaica as a bioreductant, for assessment of their potential nanomedicinal applications. Materials & methods: Biosynthesized Cr2O3 NPs were characterized by x-ray diffraction, Fourier-transform infrared spectroscopy, energy dispersive x-ray spectroscopy, scanning and transmission electron microscopy, selected area electron diffraction, UV-Vis spectroscopy and ζ-potential measurement. In vitro assays were used to assess the biological properties of Cr2O3 NPs. Results: Nanoparticles with size approximately 25-38 nm were obtained with a characteristic Cr-O vibration at 417 cm-1. A broad spectrum antimicrobial potential and antioxidant nature is reported. Slight inhibition of polio virus and biocompatibility at low doses was observed. Conclusion: We conclude a multifunctional nature of biogenic Cr2O3 NPs.

Bio-redox potential of Hyphaene thebaica in bio-fabrication of ultrafine maghemite phase iron oxide nanoparticles (Fe2O3 NPs) for therapeutic applications.

Maghemite (Fe2O3-NPs) nanoparticles were synthesized by a convenient, green and cost effective method using aqueous fruit extracts of Hyphaene thebaica. Different techniques like FTIR, XRD, UV-Vis, Raman, HR-TEM, EDS. SAED, Zeta potential were used to establish the nature of Fe2O3-NPs, while the therapeutic properties were studied using different biological assays including antiviral, antibacterial, antifungal, antioxidant and enzyme inhibition assays. XRD pattern revealed sharp peaks and a crystalline nature of Fe2O3-NPs. HR-TEM revealed quasi-spherical and cuboidal morphologies, while the particle size in ~10 nm. FTIR indicated a sharp peak centered at ~444 cm-1 which is the characteristic FeO band vibration. SAED pattern indicated the crystalline nature while EDS also confirmed the synthesis of Fe2O3 NPs. Zeta potential was obtained in different solvents and physiological buffers indicating highest value in water (-26.5 mV) and lowest in DMSO (-15.8 mV). Tested bacterial strains, Bacillus subtilis was found to be inhibited significantly. Aspergillus flavus appeared to be susceptible to all of the tested concentration of Fe2O3 NPs. Maximum 40.78% FRSA was obtained at 400 µg/mL. Cell culture based studies on RD cells and L20B cells indicated reduction in viability of cells with increase concentration of Fe2O3 NPs. Moderate inhibition of polio virus-1 and polio virus-2 was observed, after culturing the virus in the L20B cells. Excellent Protein Kinase (PK) inhibition was revealed. Hemolytic potential and cytotoxic potential was indicated to be dose dependent. In conclusion, the present report for the first time reports the synthesis of Fe2O3 NPs from H. thebaica fruits and reveals their biomedical potential including antiviral potential.

Persicaria hydropiper (L.) Delarbre: A review on traditional uses, bioactive chemical constituents and pharmacological and toxicological activities.

ETHNOPHARMACOLOGICAL RELEVANCE: Various plant parts of Persicaria hydropiper (L.) Delarbre (Syn.: Polygonum hydropiper L., Family: Polygonaceae) are used in traditional medicine systems as astringent, sedative, antiseptic and also for the treatment of respiratory disorders, edema and snake bites. It is also used as a spice in many Asian countries. AIM OF THE REVIEW: The main aim of this review is to critically analyze the reported traditional uses, bioactive chemical constituents and pharmacological activities of P. hydropiper. MATERIALS AND METHODS: Scientific database including PubMed, Scopus, SciFinder and secondary resources including books and proceedings were searched using relevant terminologies related to P. hydropiper and available scientific information was critically analyzed. RESULTS: Analysis of the scientific literature regarding the traditional uses revealed that P. hydropiper is used as a medicine and as spice in food preparations in various parts of the world. Various compounds including flavonoids, phenylpropanoid derivatives, and sesquiterpenoids among others were reported as active compounds. The extracts and compounds from P. hydropiper showed diverse biological activities including anti-inflammatory, antioxidant, cytotoxic, antimicrobial activities, etc. CONCLUSION: Although various research reports showed diverse biological activities for extracts and compounds obtained from P. hydropiper, very few studies were performed using animal models. Many of these studies also lacked proper experimental setting such as use of positive and negative controls and selection of dose as in most of these studies very high doses of extracts were administered. Further, as P. hydropiper is widely used in the treatment of snake bites and insect bites, such effects of extracts and/or compounds are not well explored. Future studies on P. hydropiper should be focused to establish the links between the traditional uses, active compounds and reported pharmacological activities.

Phytochemical Analysis, Ephedra Procera C. A. Mey. Mediated Green Synthesis of Silver Nanoparticles, Their Cytotoxic and Antimicrobial Potentials.

Background and Objectives: The current study focuses on an eco-friendly and cost-effective method of Ephedra procera C. A. Mey. mediated green synthesis of silver nanoparticles as potential cytotoxic, antimicrobial and anti-oxidant agents. Materials and Methods: Plant aqueous extracts were screened for Total Phenolic (TPC), Total Flavonoid contents (TFC), Total Antioxidant Capacity (TAC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging potentials. Total reducing power estimated by potassium ferricyanide colorimetric assay. The biosynthesized E. procera nanoparticles (EpNPs) were characterized by UV-spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction and Scanning electron microscopy. EpNPs were evaluated for their antimicrobial, bio-compatibility and cytotoxic potentials. Results: Initial phytocheimcal analysis of plant aqueous extract revealed TFC of 20.7 ± 0.21 µg/mg extract and TPC of 117.01 ± 0.78 µg/mg extract. TAC, DPPH free radical scavenging and reducing power were 73.8 ± 0.32 µg/mg extract, 71.8 ± 0.73% and 105.4 ± 0.65 µg/mg extract respectively. The synthesized EpNPs were observed to possess high cytotoxicity against HepG2 cancer cell lines with IC50 (61.3 µg/mL) as compared aqueous extract with IC50 of (247 µg/mL). EpNPs were found to be biocompatible and have less effect on human erythrocytes. EpNPs exhibited significant antioxidant potentials and exhibited considerable activity against Escherichia coli and Bacillus subtilis with Minimum Inhibitory Concentration (MICs) of 11.12 µg/mL and 11.33 µg/mL respectively. Fungal species Aspergillus niger and Aspergillus flavus were found susceptible to EpNPs. Conclusions: Results of the current study revealed that EpNPs exhibited considerable antibacterial, antifungal and cytotoxic potentials. Aqueous extract possesses significant anti-radical properties and thus can be useful in free radicals induced degenerative disorders.

Endophyte-mediated synthesis of silver nanoparticles and their biological applications.

Biosynthesis has emerged as a frontier technology for fabrication of functionally diverse nanoparticles that possess tremendous therapeutic implications. Various biological resources have already demonstrated their potential to produce nanoparticles with interesting features. Endophytic microbes live in a symbiotic relationship with plants possessing a unique and versatile reservoir of potentially therapeutic secondary metabolites having the tendency to reduce metallic ions into nanoparticles. Successful biosynthesis of AgNPs using endophytic organisms has already been reported; however, the overall picture about its synthesis and applications is still not clear. In the current article, a comprehensive review of literature was performed for comparing different physical and biological properties of endophytic microbe-derived AgNPs. In addition, the present paper mechanistically explains the synthesis of AgNPs and their diverse pharmacognostic properties. Further studies are encouraged to understand the mechanism of biopharmaceutical effects of these endophyte-mediated NPs.

Bio-guided profiling and HPLC-DAD finger printing of Atriplex lasiantha Boiss.

BACKGROUND: Plants represent an intricate and innovative source for the discovery of novel therapeutic remedies for the management of various ailments. The current study has been aimed to validate the therapeutic potential of ethnomedicinally significant plant Atriplex lasiantha Boiss. METHODS: The polarity based extraction process was carried out using fourteen solvents to figure out best extraction solvent and bioactive fractions. Total phenolic-flavonoids contents were quantified colorimetrically and polyphenolics were measured using HPLC-DAD analysis. Moreover, the test samples were tested against several diseases targets following various assays including free radicals scavenging, antibacterial, antifungal, cytotoxic and antileishmanial assay. RESULTS: Among the solvent fractions, maximum yield was obtained with methanol-water extract i.e., 11 ± 0.49%. Maximum quantity of gallic acid equivalent phenolic content and quercetin equivalent flavonoid content were quantified in methanol-ethyl acetate extract of A. lasiantha. Significant quantity of rutin i.e., 0.3 µg/mg was quantified by HPLC analysis. The methanol-ethyl acetate extract of A. lasiantha exhibited maximum total antioxidant and total reducing power with 64.8 ± 1.16 AAE/mg extract respectively, while showing 59.8 ± 1.07% free radical scavenging potential. A significant antibacterial potential was exhibited by acetone-distilled water extract of A. lasiantha with 11 ± 0.65 mm zone of inhibition against B. subtilis. Considerable antifungal activity was exhibited by ethyl acetate-n-hexane extract of aerial part of A. lasiantha with 14 ± 1.94 mm zone of inhibition against A. fumigatus. Highest percentage of α-amylase inhibition (41.8 ± 1.09%) was observed in ethyl acetate-n-hexane extract. Methanol-acetone extract of A. lasiantha demonstrated significant inhibition of hyphae formation with 11 ± 0.49 mm bald zone of inhibition. Significant in-vitro cytotoxicity against Hep G2 cell line has been exhibited by methanol-chloroforms extract of A. lasiantha. CONCLUSION: The current study reveals the prospective potential of Atriplex lasiantha Boiss. for the discovery of biologically active compounds through bioassay guided isolation against various diseases.

Potential phytochemicals in the fight against skin cancer: Current landscape and future perspectives.

Skin cancer is a life threatening disease and their prevalence and risk has been increasing over the past three decades causing significant loss to human health worldwide. Mostly skin cancer has developed resistance against chemotherapy and radiotherapy. Therefore, development of novel, cost effective and efficient treatment methods are needed. Phytochemicals extracted from medicinal plants and dietary sources are often biologically active and has attracted the attention of researchers and pharmaceutical industries around the world. Many in vitro and in vivo studies of these bioactive compounds have shown potential antioxidant, anti-proliferative, anti-inflammatory and anti-angiogenic effects in the fight against skin cancer. These phytochemicals also regulate several other molecular processes such as angiogenesis, metastasis and cell cycle to combat skin cancer. The present review provides perspectives on the key phytochemicals, their therapeutic potentials, bioavailability and molecular mechanism of action in the cancer therapeutics. Current challenges and future directions for research are also critically discussed.

Extraction optimization, total phenolic, flavonoid contents, HPLC-DAD analysis and diverse pharmacological evaluations of Dysphania ambrosioides (L.) Mosyakin & Clemants.

The present study aims to evaluate phytochemical and pharmacological potentials of Dysphania ambrosioides (L.) Mosyakin & Clemants previously known as Chenopodium ambrosioides L. Extraction was carried out using 14 solvents with wide range of polarity to find out the best solvent system for each bioactivity. Total phenolic and flavonoids contents were measured colorimetrically and polyphenolics were quantified via HPLC-DAD analysis. The samples were screened for inhibitory potentials against free radicals, leishmania, cancer cell lines, protein kinase, α-Amylase enzymes and microbial strains. Among all solvents, maximum percentage of extract was recovered from methanol-water fraction of leaves. HPLC analysis exhibited the presence of rutin, myricetin and quercetin. In DPPH assay, methanolic leaf extract exhibited IC50 value of 130.7 ± 0.57 µg/mL. Considerable α-amylase inhibitory, cytotoxic, leishmanicidal and antimicrobial potentials were exhibited by plant samples. D. ambrosioides revealed significant antioxidant, cytotoxic, antimicrobial and anti-diabetic potentials and thus warrant further detailed studies to find novel drugs.

Phyto-Therapeutic and Nanomedicinal Approaches to Cure Alzheimer's Disease: Present Status and Future Opportunities.

Alzheimer's disease (AD) is characterized by cognitive inability manifested due to the accumulation of ß-amyloid, formation of hyper phosphorylated neurofibrillary tangles, and a malfunctioned cholinergic system. The degeneration integrity of the neuronal network can appear long after the onset of the disease. Nanotechnology-based interventions have opened an exciting area via theranostics of AD in terms of tailored nanomedicine, which are able to target and deliver drugs across the blood-brain barrier (BBB). The exciting interface existing between medicinal plants and nanotechnology is an emerging marvel in medicine, which has delivered promising results in the treatment of AD. In order to assess the potential applications of the medicinal plants, their derived components, and various nanomedicinal approaches, a review of literature was deemed as necessary. In the present review, numerous phytochemicals and various feats in nanomedicine for the treatment of AD have been discussed mechanistically for the first time. Furthermore, recent trends in nanotechnology such as green synthesis of metal nanoparticles with reference to the treatment of AD have been elaborated. Foreseeing the recent progress, we hope that the interface of medicinal plants and nanotechnology will lead to highly effective theranostic strategies for the treatment of AD in the near future.

Role of plant phytochemicals and microbial enzymes in biosynthesis of metallic nanoparticles.

Metal-based nanoparticles have gained tremendous popularity because of their interesting physical, biological, optical, and magnetic properties. These nanoparticles can be synthesized using a variety of different physical, chemical, and biological techniques. The biological means are largely preferred as it provides an environmentally benign, green, and cost-effective route for the biosynthesis of nanoparticles. These bioresources can act as a scaffold, thereby playing the role of reducing as well as capping agents in the biosynthesis of nanoparticles. Medicinal plants tend to have a complex phytochemical constituent such as alcohols, phenols, terpenes, alkaloids, saponins, and proteins, while microbes have key enzymes which can act as reducing as well as stabilizing agent for NP synthesis. However, the mechanism of biosynthesis is still highly debatable. Herein, the present review is directed to give an updated comprehensive overview towards the mechanistic aspects in the biosynthesis of nanoparticles via plants and microbes. Various biosynthetic pathways of secondary metabolites in plants and key enzyme production in microbes have been discussed in detail, along with the underlying mechanisms for biogenic NP synthesis.

Potential phytocompounds for developing breast cancer therapeutics: Nature's healing touch.

Breast cancer (BC) is a devastating disease in female around the world causing significant health care burden in both developed and developing countries. In many cases BC has shown resistance to chemotherapy, radiation and hormonal therapy. Development of new, cost effective, affordable treatment method is the need of hour. Chemical compounds isolated from plants are often biologically active and is attracting the attention of scientific community. Different in vitro and in vivo studies have shown a potential role in reducing the risk of cancer metastasis. Large number of phytochemicals are considered to regulate several molecular and metabolic processes like cell cycle regulation, apoptosis activation, angiogenesis and metastatic suppression that can hinders cancer progression. An extensive review of literature has been conducted to underline the key phytochemicals and their mechanism of action. This review article has discussed in detail the regulatory roles of phytochemicals, their analogs and nanoformulations and the probability of using phytochemicals in therapeutic management of BC. Finally, current limitations, challenges and future perspectives of these phytochemicals are also critically discussed.

Multifunctional theranostic applications of biocompatible green-synthesized colloidal nanoparticles.

Phytochemicals offer immense promise for sustainable development and production of nanotechnology-enabled products. In the present study, Olax nana Wall. ex Benth. (family: Olacaceae) aqueous extract was used as an effective stabilizing agent to produce biogenic silver (ON-AgNPs) and gold nanoparticles (ON-AuNPs), which were investigated for biocompatibility and prospective biomedical applications (antibacterial, anticancer, antileishmanial, enzyme inhibition, antinociceptive, and anti-inflammatory activities). Various characterization techniques (XRD, FTIR, SEM, TEM, DLS, EDX, and SAED) revealed efficient biosynthesis of ON-AgNPs (26 nm) and ON-AuNPs (47 nm). In the toxicological assessment, ON-AgNPs and ON-AuNPs were found biocompatible towards human RBCs and macrophages (IC50 > 200 µg/mL). In a concentration range of 62.5-2000 µg/mL, a strong antibacterial effect was produced by ON-AgNPs against Staphylococcus epidermidis (MIC = 7.14 µg/mL) and Escherichia coli (8.25 µg/mL), while ON-AuNPs was only active against Staphylococcus aureus (9.14 µg/mL). At a concentration of 3.9-500 µg/mL, a dose-dependant inhibition of HepG2 cancer cells was produced by ON-AgNPs (IC50 = 14.93 µg/mL) and ON-AuNPs (2.97 µg/mL). Both ON-AgNPs and ON-AuNPs were found active against Leishmania tropica (KMH23) promastigotes (IC50 = 12.56 and 21.52 µg/mL) and amastigotes (17.44 and 42.20 µg/mL), respectively, after exposure to a concentration range of 1-200 µg/mL for 72 h. Preferential enzyme inhibition against urease and carbonic anhydrase II were noted for ON-AgNPs (39.23 and 8.89%) and ON-AuNPs (31.34 and 6.34%), respectively; however, these were found inactive against xanthine oxidase at 0.2 mg/mL. In the in vivo antinociceptive (acetic acid-induced abdominal constrictions) and anti-inflammatory (carrageenan-induced paw edema) activities, ON-AgNPs and ON-AuNPs at doses of 40 and 80 mg/kg, significantly attenuated the tonic nociception (P < 0.001) and ameliorated the carrageenan-induced inflammation (P < 0.01, P < 0.001). The results of in vitro and in vivo activities indicated that the biogenic nanoparticles can be used as valuable theranostic agents for further exploration of diverse biomedical applications.

Wound healing applications of biogenic colloidal silver and gold nanoparticles: recent trends and future prospects.

Nanotechnology has emerged as a prominent scientific discipline in the technological revolution of this millennium. The scientific community has focused on the green synthesis of metal nanoparticles as compared to physical and chemical methods due to its eco-friendly nature and high efficacy. Medicinal plants have been proven as the paramount source of various phytochemicals that can be used for the biogenic synthesis of colloidal silver and gold nanoparticles as compared to other living organisms, e.g., microbes and fungi. According to various scientific reports, the biogenic nanoparticles have shown promising potential as wound healing agents. However, not a single broad review article was present that demonstrates the wound healing application of biogenic silver and gold nanoparticles. Foreseeing the overall literature published, we for the first time intended to discuss the current trends in wound healing via biogenic silver and gold nanoparticles. Furthermore, light has been shed on the mechanistic aspects of wound healing along with futuristic discussion on the faith of biogenic silver and gold nanoparticles as potential wound healing agents.