Promising applications of phyto-fabricated silver nanoparticles: Recent trends in biomedicine.

The prospective contribution of phyto-nanotechnology to the synthesis of silver nanomaterials for biomedical purposes is attracting increasing interest across the world. Green synthesis of silver nanoparticles (Ag-NPs) through plants has been extensively examined recently, and it is now seen to be a green and efficient path for future exploitation and development of practical nano-factories. Fabrication of Ag-NPs is the process involves use of plant extracts/phyto-compounds (e.g.alkaloids, terpenoids, flavonoids, and phenolic compounds) to synthesise nanoparticles in more economical and feasible. Several findings concluded that in the field of medicine, Ag-NPs play a major role in pharmacotherapy (infection and cancer). Indeed, they exhibits novel properties but the reason is unclear (except some theoretical interpretation e.g. size, shape and morphology). But recent technological advancements help to address these questions by predicting the unique properties (composition and origin) by characterizing physical, chemical and biological properties. Due to increased list of publications and their application in the field of agriculture, industries and pharmaceuticals, issues relating to toxicity are unavoidable and question of debate. The present reviews aim to find out the role of plant extracts to synthesise Ag-NPs. It provides an overview of various phytocompounds and their role in the field of biomedicine (antibacterial, antioxidant, anticancer, anti-inflammatory etc.). In addition, this review also especially focused on various applications such as role in infection, oxidative stress, application in medical engineering, diagnosis and therapy, medical devices, orthopedics, wound healing and dressings. Additionally, the toxic effects of Ag-NPs in cell culture, tissue of different model organism, type of toxic reactions and regulation implemented to reduce associated risk are discussed critically. Addressing all above explanations, this review focus on the detailed properties of plant mediated Ag-NPs, its impact on biology, medicine and their commercial properties as well as toxicity.

7-Isopentenyloxycoumarin: What Is New across the Last Decade.

7-Isopentenyloxycoumarin is among the most widespread naturally occurring prenyloxy umbelliferone derivatives. This secondary metabolite of mixed biosynthetic origin has been typically isolated from plants belonging to several genera of the Rutaceae and Apiaceae families, comprising widely used medicinal plants and in general plants with beneficial effects on human welfare, as well as edible fruits and vegetables. Although known for quite a long time (more than 50 years), only in the last two decades has this natural compound been revealed to exert powerful and promising pharmacological properties, such as active cancer chemopreventive, antibacterial, antiprotozoal, antifungal, anti-inflammatory, neuroprotective, and antioxidant properties, among the activities best outlined in the recent literature. The aim of this comprehensive miniature review article is to detail the novel natural sources and the effects described during the last decade for 7-isopentenyloxycoumarin and what has been reported on the mechanisms of action underlying the observed biological activities of this oxyprenylated secondary metabolite. In view of the herein described data, suggestions on how to address future research on the abovementioned natural product and structurally related derivatives in the best ways according to the authors will be also provided.

Phytochemical Analysis and Biological Investigation of Nepeta juncea Benth. Different Extracts.

This study was carried out to screen the amount and the classes of secondary metabolites and to evaluate the antioxidant, cytotoxic, antifungal, and antibacterial activities of the methanolic, ethanolic, and water extracts of the roots, leaves, and flowers of Nepeta juncea Benth. The results show that the highest total phenol (69.54 ± 0.31 mg gallic acid equivalents (GAE)/g dry weight), total flavonoid (41.37 ± 0.17 mg quercetin equivalents (QE)/g dry weight), anthocyanin (6.52 ± 0.21 mg cyanidin/100 g dry weight), and tannin (47.36 ± 0.33 mg catechin/g dry weight) concentrations were recorded in the methanolic extract of the leaves of N. juncea. The gas chromatography-mass spectrometry (GC-MS) analysis of the extracts showed that 1,8-cineole, 4aα-7α-7aα-nepetalactone, ß-pinene, terpinen-4-ol, and α-terpineol were the major compounds, respectively. The best 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric-reducing antioxidant, cytotoxic, antifungal, and antibacterial activities were observed for the methanolic extract of the leaves. For the two latter activities, the best activity was revealed on Staphylococcus aureus, Bacillus cereus, and Candida albicans. The minimum inhibitory concentration (MIC) values for the antimicrobial of the methanolic extract from the leaves were in the range of 25-100 µg/mL, whereas the minimum bactericidal concentration (MBC) values were in the range of 50-200 µg/mL. The results reported herein show that, for the first time in the literature, N. juncea is a remarkable source of antioxidant, antifungal, and antibacterial compounds.

Bioactive compounds and health benefits of edible Rumex species-A review.

Medicinal and food plants as well as their bioactive fractions have been used by diverse human cultures since ancient times. These plants provide multiple health benefits because of the presence of a plethora of phytochemicals including phenylpropanoids, isoprenoids, alkaloids, sulphated compounds, peptides and polysaccharides that are responsible for various biological activities such as anticancer, antioxidant, antifungal, antibacterial, anti-dysenteric, anti-inflammatory, antiulcer, anti-hypertensive and anticoagulant properties. The genus Rumex includes edible and medicinal herbs belonging to buckwheat (Polygonaceae) family, consisting of about 200 species rich in phenylpropanoids and anthraquinones. Some Rumex species have exhibited health-promoting effects and have been used as traditional foods and herbal remedies, though a limited information has been documented on their specific biological properties. Therefore, this survey aimed at reviewing the Rumex species with documented biological activity, focusing on preclinical evidences on their efficacy and safety.

Composition, Cytotoxic and Antimicrobial Activities of Satureja intermedia C.A.Mey Essential Oil.

In this study, the essential oil (EO) constituents from the aerial parts of Satureja intermedia C.A.Mey were detected by GC and GC/MS. The antimicrobial activity of EO on oral pathogens and its cytotoxicity to human cancer cells were determined by the microbroth dilution method and the crystal violet staining method, respectively. Thirty-nine compounds were identified and the main EO constituents were γ-terpinene (37.1%), thymol (30.2%), p-cymene (16.2%), limonene (3.9%), α-terpinene (3.3%), myrcene (2.5%), germacrene B (1.4%), elemicine (1.1%) and carvacrol (0.5%). The S. intermedia EO showed a concentration-dependent decrease in viability of Hep-G2 (hepatocellular carcinoma) and MCF-7 (breast adenocarcinoma) human cancer cell lines (p < 0.05). Antimicrobial screening of S. intermedia EO demonstrated slight antibacterial and antifungal activities against Streptococcus mutants, S. salivarius, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. glabrata. Further preclinical studies are needed to assess the efficacy and safety of S. intermedia EO as a new promising anticancer agent.

Phytochemical compositions and biological activities of essential oil from Xanthium strumarium L.

The chemical composition of the essential oil (EO) from fresh cocklebur (Xanthium strumarium L.) leaves was investigated by GC-MS. The antimicrobial activity of the EO was tested against Gram-positive and Gram-negative bacteria and fungi. Scolicidal activity was assayed against Echinococcus granulosus protoscolices. In total, 34 compounds were identified, accounting for 98.96% of the EO. The main compounds in the EO were cis-ß-guaiene (34.2%), limonene (20.3%), borneol (11.6%), bornyl acetate (4.5%), ß-cubebene (3.8%), sabinene (3.6%), phytol (3.1%), ß-selinene (2.8%), camphene (2.2%), α-cubebene (2.4%), ß-caryophyllene (1.9%), α-pinene (1.8%) and xanthinin (1.04%). The antibacterial and antifungal screening of the EO showed that all assayed concentrations significantly inhibited the growth of Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger (MIC = 0.5 ± 0.1, 1.3 ± 0.0, 4.8 ± 0.0, 20.5 ± 0.3, 55.2 ± 0.0 and 34.3 ± 0.0 µg/mL, respectively). The scolicidal assay indicated that the EO exhibited a significant activity against E. granulosus protoscolices. To the best of our knowledge, this is the first report on the scolicidal activity of X. strumarium. Because of the emergence of antimicrobial drug resistance, the study of new effective natural chemotherapeutic agents, such as the X. strumarium EO, possibly with low side effects, represents a very promising approach in biomedical research.

Chemical composition and biological activity of Pulicaria vulgaris essential oil from Iran.

The present study investigated the chemical composition of the essential oil (EO) from aerial parts (flowering stage) of Pulicaria vulgaris Gaertn. by GC-MS. Also, the antimicrobial activity of the EO against Gram-positive bacteria (Bacillus cereus and Staphylococcus aureus), Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and fungi (Aspergillus niger and Candida albicans) was tested. In total, 23 compounds were recognized, accounting for 98.08% of the EO. The main compounds in the EO were thymol (50.22%), p-menth-6-en-2-one (carvotanacetone, 20.2%), thymol isobutyrate (16.88%), menthan-2-one (4.31%), 1-methyl-1,2-propanedione (4.13%), 2,5-dimethoxy-p-cymene (4.01%), myrtenol (1.22%), linalool (1.1%), and ß-myrcene (1.9%). Results of antibacterial test of P. vulgaris essential oil showed that all assayed concentrations significantly inhibited the growth of B. cereus, S. aureus, E. coli, and P. aeruginosa at P < 0.05. MIC for B. cereus, S. aureus, E. coli, P. aeruginosa was 17.5, 25.2, 19.4 and 33.2 µg/mL respectively; antifungal screening of the essential oil of P. vulgaris showed that the oil significantly inhibited the growth of A. niger and C. albicans (MIC = 15.5 and 9.9 µg/mL, respectively). Results of cytotoxicity assay showed that the essential oil exhibited a significant cytotoxic activity against both cell lines. In case of MCF-7 and Hep-G2 cell lines, IC50 of the essential oil were 5.36 and 7.16 µg/ml, respectively. The potent antimicrobial and cytotoxic activities of the EO may be attributed to its high contents of thymol, carvotanacetone and thymol isobutyrate. Antimicrobial and antitumor chemotherapies are showing diminishing effectiveness because of emergence of drug-resistance. Hence, using efficient natural chemotherapeutic agents such as Pulicaria vulgaris essential oil with fewer side effects is an encouraging approach to fight cancer and infectious diseases in medicine, agriculture, food science and related fields.