Polymer Capped Silver Nanoparticles from Ziziphus nummularia Leaves Extract: Potent Antibacterial and Antioxidant Activity

Generally, synthesis and encapsulation process improve therapeutic value of nano encapsulated drugs. The silver nanoparticles (AgNPs) biosynthesized from Ziziphus nummularia leaves and encapsulated with polyvinyl pyrrolidone (PVP) polymer as antibacterial agents, due to its high bioavailability, better encapsulation and less toxic properties. The nanoparticles (AgNPs) biosynthesized from Ziziphus nummularia leaves and capped with polyvinyl pyrrolidone (PVP) polymer, The acquired AgNPs and polymeric functionalized AgNPs were fully characterised by the UV- Visible spectroscopy , Transmission electron microscopy (TEM), X-Ray diffraction pattern (XRD) and Fourier transform infrared spectroscopy (FTIR).The crystalline Ag NPs and Polymer Functionalized AgNPs have a face-centered cubic structure with an average size of 9.20 nm, according to X-ray Diffraction spectroscopy. Fourier Transform Infrared spectroscopy revealed that biomolecules such as proteins are incapable of reducing metal ions and the formation of an encapsulating layer in terms of metal ions. High-Resolution transmission electron microscopy revealed that Polymer functionalized AgNPs ranged in size of 10 nm. AgNPs and Polymer functionalized AgNPs showed effective antimicrobial and antioxidant activity. The biosynthesized monodisperse silver nanoparticles and encapsulated silver nanoparticles demonstrated better antimicrobial and antioxidant activity which can be used in various biomedical applications.

Antimicrobial and Antioxidant Activity of Five Medicinal Plants Against Different Microbes

The present study aims to assess the antimicrobial and antioxidant activity of selected medicinal plants (Achyranthes bidentata, Linum usitatissimum, Pedalium murex, Sphaeranthus indicus and, Terminalia bellirica) extracts against seven different microorganisms Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus hominis, and Streptococcus mutants. Leaf, root, and flower extracts of plants were prepared in different solvents like methanol, distilled water, dichloromethane, ethanol, ethyl acetate, chloroform, petroleum ether, propanol, benzene, and hexane. All the prepared extracts showed very good antimicrobial activity except distilled water extract. Most of the extracts were found to have antimicrobial potential against pathogens but Linum usitatissimum and T. bellirica leaf and seed extract prepared in methanol and chloroform solvents show a higher zone of inhibition against E. coli. Only Linum usitatissimum shows activity aganist Candida albicans. Minimum Inhibitory Concentration for Achyranthes bidentata extracts varied from 150µl/ml to 200µl/ml in different solvents. Antioxidant studies were carried out in methanolic extracts of all the plants. The maximum scavenging activity of methanolic leaf extracts was observed between 80 -100 μg/ml concentrations.

Determination of Antimicrobial and Antioxidant Activity of Alchemilla alpina L.

Alchemilla genus, which belongs to the Rosaceae family, is a medicinal plant used for various purposes among the people. Species of this genus are known in Turkish folk medicine as lion claw or hazelnut grass. Especially, they are used mainly women’s illnesses, in gastritis, anti-inflammatory, as carminative, and in the treatment of wound. Besides the antimutagenic effect of Alchemilla alpina L., its above-ground parts are used for antimycotic purposes in the form of tea or oral care water. In this study, it has been aimed to determine the antimicrobial effect of the above-ground parts of Alchemilla alpina extracts obtained from methanol, ethanol and chloroform and the antioxidant activity of different concentrations of the extract obtained from methanol. The antimicrobial activity of methanol, ethanol and chloroform extracts of the above-ground parts of A. alpina has been determined according to disk disc diffusion method. In the results obtained have been showed that these extracts inhibited the growth of some bacteria (Staphylococcus aureus ATCC25923, Escherichia coli ATCC25322, Klebsiella pneumoniae ATCC700603, Bacillus megaterium DSM32) and yeasts (Candida albicans FMC17 and Candida glabrata ATCC66032) at different rates (8-23 mm). The antioxidant activity of different concentrations (1.25, 2.5, 5 and 10 mg/ml) of the above-ground parts of A. alpina extract obtained from methanol has been determined according to the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity method. In the results obtained, it has been observed that the effect of removing DPPH radical of A. alpina increased depending on increasing concentrations.

The Diversity, Metabolomics Profiling, and the Pharmacological Potential of Actinomycetes Isolated from the Estremadura Spur Pockmarks (Portugal)

The Estremadura Spur pockmarks are a unique and unexplored ecosystem located in the North Atlantic, off the coast of Portugal. A total of 85 marine-derived actinomycetes were isolated and cultured from sediments collected from this ecosystem at a depth of 200 to 350 m. Nine genera, Streptomyces, Micromonospora, Saccharopolyspora, Actinomadura, Actinopolymorpha, Nocardiopsis, Saccharomonospora, Stackebrandtia, and Verrucosispora were identified by 16S rRNA gene sequencing analyses, from which the first two were the most predominant. Non-targeted LC-MS/MS, in combination with molecular networking, revealed high metabolite diversity, including several known metabolites, such as surugamide, antimycin, etamycin, physostigmine, desferrioxamine, ikarugamycin, piericidine, and rakicidin derivatives, as well as numerous unidentified metabolites. Taxonomy was the strongest parameter influencing the metabolite production, highlighting the different biosynthetic potentials of phylogenetically related actinomycetes; the majority of the chemical classes can be used as chemotaxonomic markers, as the metabolite distribution was mostly genera-specific. The EtOAc extracts of the actinomycete isolates demonstrated antimicrobial and antioxidant activity. Altogether, this study demonstrates that the Estremadura Spur is a source of actinomycetes with potential applications for biotechnology. It highlights the importance of investigating actinomycetes from unique ecosystems, such as pockmarks, as the metabolite production reflects their adaptation to this habitat.

The in vitro antimicrobial and antioxidant activity of leaves of medicinal plants with phytobiotic potential in animal production

Little is known about which secondary metabolites are responsible for inhibiting pathogenic bacteria and reducing the pro-oxidant effect on the leaves of four medicinal plants used as phytobiotic in animal production. The aim of this study was to evaluate the antimicrobial and antioxidant activity of four medicinal plants (Anacardium occidentale, Psidium guajava, Morinda citrifolia and Moringa oleifera.) in vitro. A total of six bacterial strains were inoculated, then minimum bactericidal concentration (MBC) was evaluated in fine powder and minimum inhibitory concentration (MIC) and MBC were determined on the aqueous extract. Also, the in vitro antioxidant activity was evaluated through 1,1-diphenyl-2-picryl-hydrazyl, as well as the main secondary metabolites were identified and quantified by chromatographic analysis. The results showed that Anacardium occidentale and Psidium guajava leaves had higher antimicrobial activity against all bacterial strains. In addition, Morinda citrifolia inhibited S. aureus in the aqueous extract, although without in vitro bactericidal effect, while Moringa oleifera leaf did not show antimicrobial effect. All plants showed antioxidant capacity, standing out Anacardium occidentale and Psidium guajava. Mainly the leaves of Anacardium occidentale showed high concentrations of quercetin 3-O-glucoside-7-O-rhamnoside, kaempeferol-7-O-glucoside, quercetin, caffeic acid, and cinnamic acid. Apparently, the antimicrobial and antioxidant activity are due to the main polyphenolic compounds identified in medicinal plants (mainly Anacardium occidentale and Psidium guajava); however, further studies are necessary to elucidate the exact mechanism.

Antioxidant, Antimicrobial and Formulation of Borage (Borago officinalis) Seeds Oil and Leaves Extracts as Microemulsion

Aims: This study aims to investigate antioxidant and antibacterial activities of borage (seeds and leaves) extracts, and to prepare different topical microemulsion formulations using borage oil. Study Design: Borage seeds and leaves were collected from Hebron -Palestine, then the borage leaves and seeds were prepared for extraction and then extracted with Soxhlet using ethanol. The antimicrobial and antioxidant activity of the extracts were studied, and then Ternary Phase Diagram was constructed using the borage extracts (from seeds and leaves). Methodology: The seeds were cultivated upon their ripening season in April of 2016 from the Halhul mountains in Hebron/Palestine. Soxhlet method was used to extract borage seeds and leaves oil by using ethanol 95%. A ternary phase diagram was constructed by determining appropriate nonionic surfactant to assess the ability for microemulsion formulation and durability of each system. Tween 80 was found to be more suitable to solubilize each of borage seeds and leaves extracts compared with Tween 20 due to its prominent hydrophobic properties. The antibacterial activity was evaluated for both borage seeds and leaves extracts using a well diffusion method against Staphyloococcus aureus, Escherichia coli, &Candida albicans. Results: Results showed that the seeds extract has inhibition zone (12 mm) against S. aureus (gram positive bacteria) higher than inhibition zone that leaves extracts exhibited (7.5mm), but no significant effects observed for both extracts against E. coli and C. albicans. In addition, antibacterial activity for microemulsions formulation was measured against S. aureus, E. coli, and C. albicans. Results showed that there is minor activity against S. aureus when compared to PenicillinG and the pure seed oil or leaves extract. In contrast no activity was reported against E. coli and C. albicans. The antioxidant activity was further indicated by the quiet good ability to reduce the FRAP reagent for both extracts with the indication of higher seeds extract activity. This variation is explained by the higher seeds extract content of polyphenol, tocopherol and vitamin C than leaves extract. Conclusion: Borage seeds and leaves were extracted, and the extracts were showed antimicrobial and antioxidant activity and showed that they can be used in microemulsion using ternary phase diagram.

Active Double-Layered Films Enriched with AgNPs in Great Water Dock Root and Pu-Erh Extracts

A novel, eco-friendly, and biocompatible method was applied to form silver nanoparticles (AgNPs) in great water dock (Lapathi radix) (KB) and pu-erh (Camellia sinensis) (PE) extracts. The surface plasma resonance peak of green synthesized AgNPs at 451.8 nm for AgNPs+KB and 440.8 nm for AgNPs+PE was observed via spectral analysis of UV absorbance. In this study, double-layered biopolymer films (FUR/CHIT+HGEL) with AgNPs incorporated in KB solution (AgNPs+KB) and AgNPs in PE solution (AgNPs+PE), were successfully prepared using the casting method. The SEM, XRD, zeta potential and size analyses confirmed the presence of AgNP in the films. The addition of AgNPs in plant extracts improved antimicrobial and antioxidant activity and thermal stability, whereas WVTR experienced a decrease. The nanocomposite films’ orange-brown colour may aid in the protection of food products against UV rays. The composite films demonstrated antibacterial activity against food-borne pathogens and may offer potential in food packaging applications.

The in vitro antimicrobial and antioxidant activity of leaves of medicinal plants with phytobiotic potential in animal production

Little is known about which secondary metabolites are responsible for inhibiting pathogenic bacteria and reducing the pro-oxidant effect on the leaves of four medicinal plants used as phytobiotic in animal production. The aim of this study was to evaluate the antimicrobial and antioxidant activity of four medicinal plants (Anacardium occidentale, Psidium guajava, Morinda citrifolia and Moringa oleifera.) in vitro. A total of six bacterial strains were inoculated, then minimum bactericidal concentration (MBC) was evaluated in fine powder and minimum inhibitory concentration (MIC) and MBC were determined on the aqueous extract. Also, the in vitro antioxidant activity was evaluated through 1,1-diphenyl-2-picryl-hydrazyl, as well as the main secondary metabolites were identified and quantified by chromatographic analysis. The results showed that Anacardium occidentale and Psidium guajava leaves had higher antimicrobial activity against all bacterial strains. In addition, Morinda citrifolia inhibited S. aureus in the aqueous extract, although without in vitro bactericidal effect, while Moringa oleifera leaf did not show antimicrobial effect. All plants showed antioxidant capacity, standing out Anacardium occidentale and Psidium guajava. Mainly the leaves of Anacardium occidentale showed high concentrations of quercetin 3-O-glucoside-7-O-rhamnoside, kaempeferol-7-O-glucoside, quercetin, caffeic acid, and cinnamic acid. Apparently, the antimicrobial and antioxidant activity are due to the main polyphenolic compounds identified in medicinal plants (mainly Anacardium occidentale and Psidium guajava); however, further studies are necessary to elucidate the exact mechanism.

Pomegranate Byproduct Extracts as Ingredients for Producing Experimental Cheese with Enhanced Microbiological, Functional, and Physical Characteristics

Pomegranate peel and mesocarp, considered as wastes of fruit processing, are rich sources of beneficial phytochemicals, including hydrolyzable tannins and flavonoids, with proven antimicrobial and antioxidant activity, which can be employed for improving the overall quality of food products. In the present study, extracts from pomegranate peel (PPW) and mesocarp (PMW) were obtained through a water extraction method and evaluated for in vitro antimicrobial activity and polyphenol content. The two extracts were then added during the cheese-making process in order to create a new functional cheese with improved microbiological and physico-chemical characteristics. Antimicrobial in vitro assays evidenced a substantial efficacy of both extracts against Staphylococcus aureus, which often causes staphylococcal food poisoning outbreaks linked to the consumption of raw milk cheeses and artisanal cheeses. For this reason, a simulated cheese contamination was carried out in order to assess if pomegranate extracts can exert antimicrobial activity towards this pathogen even when incorporated into the cheese matrix. Milk enriched with pomegranate extracts (PPW and PMW) was used to produce two different experimental cheeses, which were then evaluated for yield, polyphenol content, and microbiological as well as physico-chemical traits throughout the refrigerated storage. Despite the low concentration of the extracts, the treated cheeses showed an increase in firmness and a slight decrease in S. aureus counts, of more than one log unit in comparison to the control cheese, for up to 12 d of cold storage. Such results support the reuse of agro-food byproducts, in substitution to chemical food preservatives, as the key to a circular economy.