Maximum Zone Of Inhibition Research Articles

Green Synthesis, Characterization andIn VitroAntimicrobial Activity of Silver Nanoparticles (AgNPs) Using Fungal Aqueous Extract

Research in green synthesis of metallic nanoparticles and their applications in engineering, food, biomedicine and agriculture is growing rapidly. The presence of biologically active metabolites in fungi makes them ideal candidates for green synthesis of silver nanoparticles (AgNPs). This study aims at discerning an emerging applicability of a basidiomycete mushroom, Phaeolus schweinitzii, for mycosynthesis of AgNPs and their antimicrobial properties. The colour change in P. schweinitzii aqueous extract was used to detect and curate the synthesis of AgNPs. The AgNP surface plasmon resonance (SPR) was observed in the visible spectra at approximately 428[Formula: see text]nm using UV-Vis spectroscopy. The XRD spectrum revealed a face-centered cubic (FCC) structure of AgNPs with an average crystallite size of 38.78[Formula: see text]nm. FT-IR manifested various functional clusters of biomolecules which were involved in bioreduction, capping and stabilization of AgNPs. FE-SEM imaging of AgNPs revealed a spherical shape with an average size of 88.65[Formula: see text]nm. The synthesized AgNPs showed strong antimicrobial activities against Salmonella gallinarum, E. coli, Staphylococcus aureus, Aspergillus niger and Fusarium oxysporum with varying zones of inhibition at different concentrations. The highest concentration (5[Formula: see text]mg/ml) of AgNPs produced a maximum zone of inhibition ([Formula: see text][Formula: see text]mm) against gram negative bacteria (Salmonella gallinarum and E. coli) and lowest ([Formula: see text][Formula: see text]mm) against gram positive bacteria (Staphylococcus aureus). The study also revealed that synthesized AgNPs showed comparatively higher antifungal activity than the positive control (nystatin). The findings from this study explicitly concur with the ever-relevant use of biogenic AgNPs against various pathogenic microorganisms.

Profiling of phenolics in cashew nut (Anacardium occidentale L.) testa and evaluation of their antioxidant and antimicrobial properties

Most of agricultural by-products are rich sources of bioactive compounds. The present study deals with profiling phenolic compounds from various phenolic fractions of cashew nut (Anacardium occidentale L.) testa. The antioxidant and antimicrobial properties of phenolic fractions (free, esterified and bound) were also evaluated. About 20, 5 and 7 phenolic compounds were identified from free, esterified, and bound phenolic fractions, respectively. UPLC-HRMS/MS analyses of phenolic fractions revealed that condensed tannins and flavanols are the primary testa polyphenols. (+)-catechin, (−)-epicatechin, epicatechin gallate and procyanidins were identified in all the fractions. Most of the phenolic compounds were concentrated in the free form (62.5%), followed by the bound (21.8%) and esterified fractions (15.62%). The free phenolic fraction (FPF) showed the highest total polyphenol and flavonoid content. The FPF showed the highest radical scavenging activity (FPF IC50 12.35 ± 1.48 μg/ml (DPPH assay), 33.77 ± 1.04 μg/ml (ABTS assay) and 62.89 ± 2.1 μmol of Fe2+ equivalent per gram of cashew nut testa (FRAP assay)). The antimicrobial activities of phenolic fractions were tested against food-borne pathogens such as Staphylococcus aureus FRI722, Escherichia coli EFR02, Micrococcus luteus ATCC 9341 and Bacillus cereus ATCC 11778. All the phenolic fractions possess antimicrobial activity; the FPF has shown a maximum zone of inhibition at a lower concentration of 3 mg/ml. The antioxidant and antimicrobial activities of the testa were strongly influenced by its total phenolic and flavonoid contents. In conclusion, cashew nut testa is a suitable source to extract phenolic compounds with strong antioxidant and antimicrobial properties.

Antimicrobial compounds produced by Streptomyces sp. VITGV01 against selected human pathogens

Streptomyces are well known to produce a large number of diverse compounds. An endophytic actinomycete, Streptomyces sp. VITGV01 was isolated from a farm tomato plant. Isolated actinomycetes are cultured in ISP2 medium supplemented with nystatin (15μg/ml) and nalidixic acid (50μg/ml). A total of 240 actinomycetes were isolated and 77 showed antimicrobial properties. One strain that exhibited a high zone of inhibition on primary screening was selected (VITGV01). The SEM studies revealed filamentous tubular structures with continuous aerial hyphae differentiated into tiny, smooth-surfaced chainlike spores. Based on the 16S rRNA analysis and physiological tests, this isolate was found to be a member of the genus Streptomyces suggesting that it might be a new sp. Maximum biomass production was recorded in media containing 1% sucrose and 1% yeast extract cultured at pH 7.0 for 15 days at 300C. The secondary metabolites were active against Bacillus subtilis (MTCC 2756), Staphylococcus aureus (MTCC 737), Escherichia coli (MTCC 1687) and Klebsiella pneumoniae (MTCC 109). A maximum zone of inhibition was observed against K. pneumoniae (22 mm) and a minimal zone of inhibition against B. subtilis (8 mm). FTIR analysis revealed amine, alkane (C=C) aromatic ring, secondary alcohol and alkyl halide groups. The GCMS data showed twenty different compounds, of which fifteen are antimicrobial.

Green synthesis of Silver Nanoparticles using Premna tomentosa leaf extract and its effective antibacterial activity

Green synthesis of silver nanoparticles was done at room temperature using Premna tomentosa leaf extract. Silver nanoparticle formation was preliminarily confirmed through UV Spectroscopy and characterized by FTIR, XRD, TEM and SEM. The λmax was observed at 424nm in UV spectroscopy results. The XRD and EDAX spectrum confirmed the presence of silver ions and the crystalline nature of synthesized silver nanoparticles. The synthesized silver nanoparticles were spherical, hexagonal and irregular in shape. FTIR results have revealed the functional groups present in the synthesized nanoparticles such as C-N stretch, N-O symmetric stretch, C-H stretch, N-H bend, C-H group, O-H stretch and H bond. TEM and SEM results showed a clear image of nanoparticles in the size range 100nm and 200nm. In the application part, we focused on the antibacterial activity of synthesized nanoparticles on six pathogens namely Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Vibrio parahaemolyticus and Proteus mirabilis. The maximum zone of inhibition was found in Vibrio parahaemolyticus followed by Staphylococcus aureus and Pseudomonas aeruginosa.

Antimicrobial, anti-adhesion, anti-biofilm properties of goji berry (Lycium barbarum) against periodontal bacteria: potential benefits for periodontal diseases.

Lycium barbarum, commonly known as goji berry, Himalayan berry, or Tibetian berry, is emerging asapopular "superfood" with anti-inflammatory and antioxidant properties. However, its use for the management of oral inflammatory diseases has not been explored. The present study aims to evaluate the antimicrobial, anti-adhesion, anti-biofilm, and cytotoxic properties of an ethanolic extract of L.barbarum (LBE) against common oral and periodontal pathogens. The antimicrobial properties of LBE against fivepotential periodontal pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Prevotella intermedia, Tanerella forsythia) were tested and compared to chlorhexidine anddoxycycline using serial dilution and disc diffusion assay. The MTT Assay was performed for evaluating thecytotoxicity and cell viability of the LBE on the gingivalfibroblast and modified keratinocyte cell lines. The anti-adhesion and anti-biofilm properties of LBE against P.gingivalis at its minimal bactericidal value were also assessed. LBE inhibited the growth of periodontal pathogens as compared to control, however, the zone of inhibition of LBE was less when compared to doxycycline and chlorhexidine. The de novo extract showed a maximum zone of inhibition against Tf and Aa. The LBEextract was also compatible to gingival fibroblast tissues and oral keratinocytes at 1mg/mL. L.barbarum is a promising alternative to Chlorhexidine for the management of oral and periodontal infections.

In Vitro Antimicrobial Activity Analysis Of Lemon Grass Leaf Extracts Against Pathogenic Bacteria

Lemongrass is used to treat fever, fatigue, convulsions, common cold, rheumatism, vomiting, convulsions, discomfort, and digestive system spasms. The present investigation was performed to investigate the antibacterial property of methnolic, acetone and benzene extract of lemon grass against pathogenic bacteria. The maximum inhibition zone for methanol extract was Pseudomonas aeruginosa and Staphylococcus aureus (18 mm) at a concentration of 100 μl/ml. Benzene extract also exhibited a 17 mm zone at 100 μl/ml against bacteria- Pseudomonas aeruginosa. Behind it, 50 μl/ml of methanol extract exhibited 16 mm of Pseudomonas aeruginosa and 100 μl/ml of benzene extract against Klebsella pneumoneae. As concentration increases against all bacteria, the anti-bacterial activity of extracts increases. Among all the extracts methanol extract have been found more potential extract for antibacterial as well as lowest MIC. So lemon grass can be used to treat many bacterial diseases.

Sodium borohydride mediated synthesis of nano-sized silver particles: Their characterization, anti-microbial and cytotoxicity studies

This work reports the one-step, fast, easy, simple and economical process for the synthesis of nano-sized and stable silver particles. AgNPs were synthesized at six (0.02 M, 0.04 M, 0.06 M, 0.08 M, 0.10 M and 1.00 M) different concentrations of metal precursor and reducing agent. Sodium borohydride was used as both reducing and stabilizing agent. Characterization studies revealed that all the silver nanoparticles (AgNPs) synthesized were in the range of 10 nm–50 nm, spherical shaped, crystalline nature and with high negative surface charge (−30 mV to −47 mV). Among the AgNPs evaluated for their anti-microbial activity through well diffusion method against Escherichia coli (Gram negative bacteria), Bacillus subtilis (Gram positive bacteria) and Candida albicans (fungi), AgNPs-1.00 showed maximum zone of inhibition with 11.5 mm, 18.5 mm and 10 mm at highest test concentration (100 mg/L), respectively. Cytotoxicity of the AgNPs was determined against MCF-7, PVA1 and Caco-2 cancer cell lines through standard MTT assay. AgNPs-0.08 showed highest mortality% with 90% and 80% against MCF-7 and PVA1 at maximum test concentration (100 mg/L), respectively. However, none of the AgNPs showed toxicity towards Caco-2 cancer cell line. Therefore, AgNPs can be used as anti-microbial agents in the biomedical applications.

Green Chemistry Based Synthesis of Zinc Oxide Nanoparticles Using Plant Derivatives of Calotropis gigantea (Giant Milkweed) and Its Biological Applications against Various Bacterial and Fungal Pathogens.

Nanotechnology is a burning field of scientific interest for researchers in current era. Diverse plant materials are considered as potential tool in green chemistry based technologies for the synthesis of metal nanoparticles (NPs) to cope with the hazardous effects of synthetic chemicals, leading to severe abiotic climate change issues in today's agriculture. This study aimed to determine the synthesis and characterization of metal-based nanoparticles using extracts of the selected plant Calotropis gigantea and to evaluate the enzyme-inhibition activities and antibacterial and antifungal activity of extracts of metal-based zinc nanoparticles using C. gigantea extracts. The crystal structure and surface morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). C. gigantea was examined for antimicrobial activity against clinical isolates of bacteria and fungi. The water, ethanolic, and acetone extracts of C. gigantea were studied for their antagonistic action against bacterial strains (E. coli, S. aureus, P. multocida, and B. subtilis) and selected fungal strains (A. paracistic, F. solani, A. niger, S. ferrugenium, and R. nigricans). In vitro antimicrobial activity was determined by the disc diffusion method, where C. gigantea wastested for AChE and BChE inhibitory activity using Ellman's methodology. The kinetic analysis was performed by the proverbial Berthelot reaction for urease inhibition. The results showed that out of all the extracts tested, ethanolic and water extracts possessed zinc nanoparticles. These extracts showed the maximum zone of inhibition against F. solani and P. multocida and the lowest against S. ferrugenium and B. subtilis. A potential source of AChE inhibitors is certainly provided by the abundance of plants in nature. Numerous phyto-constituents, such as AChE and BChE inhibitors, have been reported in this communication. Water extract was active and has the potential for in vitro AChE and BChE inhibitory activity. The urease inhibition with flower extracts of C. gigantea revealed zinc nanoparticles in water extracts that competitively inhibited urease enzymes. In the case of cholinesterase enzymes, it was inferred that the water extract and zinc nanoparticles have more potential for inhibition of BChE than AChE and urease inhibition. Furthermore, zinc nanoparticles with water extract are active inthe inhibition of the bacterial strains E. coli, S. aureus, and P. multocida and the fungal strains A. paracistic, F. solani, and A. niger.

Structural Elucidation and Antibacterial Activity Studies of Leaf Extracts of <i>Withania somnifera</i>

Withania somnifera (W. somnifera), a small, woody shrub in the Solanaceae family, has been studied using a phytochemical test, antibacterial activity and partial characterizations. Air-dried and powdered leaves of the plant were extracted with maceration over an electrical shaker using the solvent chloroform and methanol. After crude extracts of the plant were concentrated, the diffusion antibacterial susceptibility test was carried out on 25, 50, 75, and 100 mg/mL of chloroform and methanol crude extract. The bacteria used were S. aureus, S. pneumonia, E. coli, and S. typhi. Each antibacterial activity test was carried out three times. The most active crude extract of the plant was subjected to a phytochemical test and fractionation with column chromatography. Chloroform and methanol extract of the plant inhibits all cultures of four bacteria. Both chloroform and methanol extract of W. Somnifera inhibits both gram-positive and negative bacterium with a comparable inhibition zone with the standard antibiotics, amoxicillin, gentamicin, and cefoxitine. In addition, it gives a maximum inhibition zone than that of amoxicillin, starting from 25 to 100 mg/mL. Methanol extract of W. somnifera contains phenolic, alkaloids, flavonoids, tannins, and phytosteroids. Partial characterization of pure fractions by using 1H-NMR, 13C-NMR, Dept-135 NMR, and IR spectroscopy, the compound WS-1 affords withaferin A. Withaferine A shows antibacterial activity with an inhibition zone of 11, 10.5, 11, and 9 mm against the bacterium S. aureus, S. pneumoniae, E. coli, and S. typhi respectively.

A comparative study of green and chemically synthesized nano nickel oxide for multifunctional applications

Nickel oxide nanoparticles [NiO NPs] were synthesized using chemical (Combustion method) and green route using Coccania grandis leaf extract (Probe sonication method). SEM reveals that, NiONPs synthesized using green route showed agglomerated porous, having diameter of 200 nm. Whereas, chemically synthesized NiO NPs were uniform in size with diameter of 180 nm. From PXRD analysis, average crystallite size of green and chemically synthesized NiONPs was found to be 52.6 nm and 41.9 nm respectively. NiO NPs synthesized using the green route. Antibacterial study of NiONPs (synthesized by green route) displayed maximum zone of inhibition i.e10.8mm (Staphylococcussp), 9.4mm (E coli) and 7.4mm (Pseudomonas) compared to 8mm (Staphylococcussp), 9mm (Ecoli). Photocatalytic activity of direct green dye was effective in NiO NPs synthesized by chemical (69.25%) compared to the green route (25.65%). In electrochemical analysis (biosensor), one reduction and one oxidation peak were observed and were highly effective in sensing Fe3+ under alkaline medium in green route NiO NPs.

Bio-Fabrication of Euryale ferox (Makhana) Leaf Silver Nanoparticles and Their Antibacterial, Antioxidant and Cytotoxic Potential.

Bio-fabrication of green or plant extract-based silver nanoparticles has garnered much praise over the past decade as the methodology is environment-friendly, undemanding, non-pathogenic, and economical. In the current study, leaves of Eurale ferox (Makhana), considered as waste, were used for the bio-fabrication of silver nanoparticles (ELAgNPs). Various analytical techniques including UV–VIS spectroscopy, Field emission scanning electron microscopy equipped with an energy dispersive X-ray spectrometer (FESEM-EDX), Particle size analyzer (PSA), Fourier transform infra-red spectroscopy (FTIR) and high-resolution transmission electron microscopy (HRTEM) were used for their characterization. Their antibacterial efficacy was examined against gram positive bacterium, Bacillus subtilis and gram negative bacterium, Escherichia coli. The antioxidant potential of the ELAgNPs was compassed by 2, 2 diphenyl-1-picryl hydrazyl (DPPH; λmax = 517 nm) assay, H2O2 (λmax = 230 nm) and OH− (λmax = 520 nm)-based radical scavenging assays. The cytotoxicity was checked against the VERO cell line using 3-[4, 5-dimethyl thiazol-2-yl]-2, 5 diphenyl tetrazolium bromide (MTT) assay. A mean particle size of 26.51 ± 8.87 nm with a size distribution of 7.08–53.94 nm was obtained using HRTEM. The ELAgNPs exhibited dose-dependent antibacterial efficacy with a maximum zone of inhibition (ZOI) of 21.98 ± 0.59 mm against B. subtilis and of 16.46 ± 0.22 mm against E. coli at 500 ppm after 24 h of incubation. The median lethal concentration for the cytotoxicity analysis was found to be 9.54 ± 0.35 ppm, 120.9 ± 6.31 ppm, and 20.74 ± 0.63 ppm for ELAgNPs, commercial silver nanoparticles (CAgNPs), and silver nitrate (SN), respectively. The ordinary one-way ANOVA results exhibited a significant decrease in cell viability after 72 h of incubation at p < 0.05, α = 0.05. In conclusion, the ELAgNPs showed good antibacterial, radical scavenging and dose-dependent cytotoxicity against the VERO cells. Therefore, these could be used for biomedical applications. Phyto-constituents present in the plant not only act as reducing agents but also as stabilizing and coating agents, and the availability of a wide range of metabolites makes the green approach more promising.

Evaluation of in vitro antibacterial effect of essential oil and some herbal plant extract used against mastitis pathogens.

Mastitis in dairy cattle is a highly prevalent infectious disease, caused by various pathogens, mainly Staphylococcu aureus and Escherichia Coli, considerable economic loss worldwide. The aim of this study was to evaluate the in vitro activity of Herbal plants used against S. aureus and E. coli bacteria which are the causative agents of mastitis. Therefore, in this study we investigate the antimicrobial effect of plant to evaluate the in vitro antibacterial activity of squaw mint (Mentha pulegium L., Lamiaceae family), catnip (Nepeta cataria L., Lamiaceae), lemon balm (Melissa officinalis L., Lamiaceae), for mastitis treatment. Solutions prepared in fixed oils, against S. aureus and E. coli bacteria which are the main agents of mastitis. Isolation and antibiotic susceptibility analyses of milk samples taken from 100 subclinical mastitis dairy cows were performed. The antibacterial properties of the solutions were analysed by a disk diffusion method. In the bacterial isolation, S. aureus was determined 97.7% and E. coli 53.5% positive of cows with mastitis. Antibacterial susceptibility test of the Lemon balm extract and essential oil showed maximum zone of inhibition against S. aureus 30µl (23mm), followed by 20µl (19mm), E. coli (19mm) and 10µl (5-7mm), of the same extract against the Gram-positive bacteria. The ethanol extracts show the similar activity against the Gram-negative bacteria at 30, 20, and 10µl (18-20mm). Followed by S. aureus, when the zone areas for the susceptible solutions (Lemon balm, and essential oil) and the control group were compared, determined that there was little difference between for S. aureus and E. coli. This study hence indicated that in vitro cultured plantlets of lemon balm and peppermint oil can be used as the alternative method for production of mastitis and cheap source its precursor with antimicrobial activities.

A novel approach of phyllanthus niruri supported Ag-Cu-Co for anti-oxidant, anti-bacterial, larvicidal and photodegradation applications

Novel Ag-Cu-Co trimetallic nanoparticles were synthesized by green method using phyllanthus niruri extract as a reducing and stabilizing agent. It was analyzed using Ultraviolet-Visible, Fourier Transform Infrared, Scanning Electron Microscope, X-ray Diffraction, Particle size and Thermal analyses etc. The UV–Vis studies confirmed the absorption value of Ag-Cu-Co at 241 nm respectively. The crystalline size of the P. niruri supported Ag-Cu-Co was found in the range of 17–19 nm with quasi spherical in shape. From the antibacterial study the synthesized Ag-Cu-Co showed maximum zone of inhibition for E. coli and it was found to be 25 mm. The photocatalytic degradation study confirmed the effective activity against methylene blue and the percentage degradation was confirmed to be 83.28 percentage. The LC50 value was found to be 14.768 percentage which confirmed the potent larvicidal activity of synthesized material. Hence, it has proved that the synthesized green nanoparticles as proficient catalyst for antioxidant, antibacterial, larvicidal and effective degradation of dye molecules.

Phytochemical screening and antibacterial activity of Trachyspermum ammi L. against certain bacterial species

L. is a traditional medicinal herb that has been used to cure a variety of diseases in humans. The goal of this study was to evaluate the antibacterial activity of methanolic, ethanolic, and acetonic extracts of T. seeds against a bacterial species. Agar well diffusion method was used to test antibacterial activity. In comparison to methanolic and acetonic extracts, ethanolic extract of T. ammi seeds showed a highest antibacterial activity against , and . Methanolic extract, on the other hand, effectively inhibited and . The maximum inhibition zone in ethanolic was observed against and (22.6 mm) and the minimum inhibition zone against (12 mm) at 100% concentration. Plant extracts contained alkaloids, flavonoids, saponins, tannins, and glycosides.

Antibacterial Activity of Copper Particles Embedded in Knitted Fabrics.

The composition and antibacterial properties of copper particles synthesized by a very simple reduction method were studied. For the preparation of particles in knitted fabrics, copper(II) sulfate was used as a precursor and ascorbic acid as a reducing natural agent. X-ray diffraction analysis showed the crystalline nature of the obtained particles. The round or oval particles and their agglomerates in knitted fabrics consisted of copper with traces of copper(I) oxide—cuprite. The element maps and energy dispersive X-ray spectra showed a high content of copper in the samples. The samples of wool and cotton knitted fabrics with copper particles had excellent antibacterial activity against gram-positive Staphylococcus aureus (S. aureus) and gram-negative Escherichia coli (E. coli) bacterial strains. The maximum zones of inhibition were 19.3 mm for S. aureus and 18.3 mm for E. coli using wool knitted fabric and 14.7 mm and 15.3 mm using cotton knitted fabric, respectively. The obtained results showed that the modified wool and cotton fabrics are suitable for use as inserts in reusable masks due to their noticeable and long-term activity against pathogenic bacteria.

GC-MS Profiling of Naturally Extracted Essential Oils: Antimicrobial and Beverage Preservative Actions.

The purpose of this study was to demonstrate the antimicrobial effects of natural essential oils (EO) and determine their preservative action. Eight natural essential oils were tested against Staphylococcus aureus, Escherichia coli, and Candida albicans representing gram positive, gram negative, and fungi, respectively. The plant materials were used in this study viz. Thymus vulgaris—thyme (TV), Mentha virdis (MV), Mentha longifolia (ML), Rosmarinus officinalis—rosemary (RO), Lavandula dentata—lavender (LD), Origanum majorana—oregano (OM), which belong to the Lamiaceae family. The other two plants were Cymbopogon citratus—lemon grass (family Poaceae) (CC), and Eucalyptus globulus (family Myrtaceae) (EG). Employing the disc diffusion susceptibility test, minimum inhibitory and minimum bactericidal concentrations were estimated for each oil, followed by the addition of oils to pasteurized apple juice after microbial induction. The results revealed that thyme oil showed the maximum zone of inhibition against all tested microbes enriched with monoterpenes class viz. eucalyptol (24.3%), thymol (17.4%), and γ-terpinene (15.2%). All other tested oils exhibited a concentration-dependent inhibition of growth and their MIC ranged from 0.1 to 100 µL/mL. The recorded minimum bactericidal concentration values were apparently double the minimum inhibitory concentration. The EO of Mentha virdis followed by Mentha longifolia showed maximum antimicrobial activity against the tested organisms in pasteurized apple juice. A gas chromatography–mass spectroscopy (GC–MS) analysis of lemon grass, thyme, and Mentha virdis essential oils showed their enrichment with monoterpenes class recording 97.10, 97.04, and 97.61%, respectively.

Evaluation of quality and antimicrobial efficacy of locally manufactured alcohol-based hand sanitizers marketed in Addis Ababa, Ethiopia in the era of COVID-19

BackgroundThe coronavirus disease 2019 (COVID-19) has been rapidly spreading across the globe since the World Health Organization (WHO) has declared the disease outbreak as a global pandemic on March 11, 2020. Hand hygiene, via either regular handwashing with soap and water or using hand sanitizers, is among the various measures that need to be followed to control the outbreak of the disease. Alcohol-based hand sanitizers (ABHS) are the “gold standard” for hand disinfection because of their broad antimicrobial spectrum of activity, easy availability, better safety profile, and general acceptability to users. This study aimed at evaluating the physicochemical quality and antimicrobial efficacy of the locally manufactured ABHS marketed in Addis Ababa, Ethiopia.MethodsA cross-sectional survey was used to collect ABHS from Addis Ababa marketplaces. A total of 25 sample products were randomly selected from different categories of hand sanitizer manufacturers. The physicochemical evaluation of the products was carried out as per the United States Pharmacopoeia and WHO standards. Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella spp., and Shigella spp clinical isolates were used for the antimicrobial efficacy test.ResultsThe Fourier Transform Infrared result confirmed that all the test products met the identification test for ethanol. The majority (68%) of ABHS complied with the test for ethanol content (75–85% v/v). However, only 3 products fulfilled the hydrogen peroxide content (0.112–0.137% v/v). LPC307 showed the maximum zone of inhibition of 12 mm against Escherichia coli whereas MPC204 exhibited only 3 mm. LPC101 was found to be more sensitive to Shigella and Klebsiella Spp with minimum inhibitory concentration values of 20% and 10%, respectively. The sample product LPC101 showed a minimum bactericidal concentration of 20% against Escherichia coli, Pseudomonas aeruginosa, and Klebsiella spp.ConclusionOne-third of the tested ABHS did not comply with the WHO ethanol content limit and the majority of the products failed to meet the label claim for hydrogen peroxide content. Besides, nearly all products proved that they have activity against all the tested pathogenic microorganisms at a minimum concentration from 10 to 80%; though, they did not show 99.9% bacteriostatic or bactericidal activities as claimed. The study findings suggested regular monitoring of the quality of marketed ABHS considering the current wide use of these products.

Bio-Functional Potential and Biochemical Properties of Propolis Collected from Different Regions of Balochistan Province of Pakistan

Propolis is a well-known resinous natural substance collected by honeybees (Apis mellifera L.) from plants exudations. Variations in chemical composition of propolis are due to different sources from which it is collected and change in climate and geographical location. In this study, different propolis samples were collected from different regions of Balochistan and examined for its chemical composition, total phenolics and total flavonoid contents, and antioxidant potential by using DPPH radical scavenging assay and antimicrobial activity. Bioactive components analysis revealed the presence of steroids, carbohydrates, flavonoids, coumarins, cardiac glycosides, quinones, anthraquinones, terpenoids, tannins, and phlobatannins at different levels. The total phenolics contents were ranged from 2.9343 ± 1.247 to 6.0216 ± 2.873 mg GAE g−1, and flavonoid contents were found to be 0.1546 ± 0.087 to 0.6586 ± 0.329 mg QE g-1, respectively. The antioxidant ability of each extract was analyzed by their concentration having 50% inhibition (IC50). The propolis sample P3 possessed lower IC5027.07 ± 0.73 mg mL−1 with higher % inhibition of DPPH radical, and P8 showed lower % inhibition by having IC5084.43 ± 2.07 mg mL−1. The antibacterial activity of all samples was analyzed against a wide group of bacteria including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumonia and propolis extract (P4) was highly active against Klebsiella pneumoniae with the maximum diameter of zone of inhibition 20.33 ± 1.52 mm, and propolis extract (P3) showed maximum zone of inhibition against Escherichia coli19.06 ± 1.90, while propolis extract (P2) was found less active with minimum diameter of zone of inhibition 7.46 ± 1.50 mm. The antifungal activity of extract was considered as active against the fungal species. Propolis extract (P3) showed 82% of zone of inhibition against Aspergillus Niger, and propolis extract (P1) was highly active against Aspergillus parasiticus with 80% of zone of inhibition. By comparing the vibration frequencies in wave numbers of the sample spectrograph acquired from an FTIR spectrophotometer, the functional groups present in the extracts were identified. The presence of seven elements (Fe, Zn, Mn, Ni, Pb, Cd, and Cr) was analyzed through atomic absorption spectrophotometer. The obtained concentrations were within the permissible ranges established by the World Health Organization. The GC-MS analysis revealed the presence of 80 different compounds belonged to different classes. The obtained results confirmed the imperative potential of propolis which can be used in various biological applications.

Green synthesis of cobalt oxide nanoparticles using roots extract of Ziziphus Oxyphylla Edgew its characterization and antibacterial activity

In this modern era, antibiotic resistance is a significant issue that poses a threat to public health. Nanotechnology is an emerging field of science because nanoparticles could be the best alternative to antibiotics. Most nanoparticles are prepared by the green synthesis method because of their less toxicity, low cost, and non-hazardous nature. In this study, cobalt oxide nanoparticles (Co3O4-NPs) were synthesized from roots extract of Ziziphus Oxyphylla Edgew by using cobalt chloride hexahydrate. After the successful synthesis of nanoparticles, various methods were used to analyze these nanoparticles, including Fourier transform infrared spectroscopy, scanning electron microscopy, x-ray diffraction analysis, and energy dispersive analysis of x-ray. Scanning electron microscopy images reveal the spherical and irregular structure of Co3O4-NPs shaving a particle size between 40 to 60 nm. X-ray diffraction analysis revealed the crystalline nature of cobalt oxide nanoparticles with face-centered cubic structure and a size of 15–20 nm. The antibacterial activity of Co3O4-NPs was analyzed for different dilutions against two different bacteria: gram-negative (E. coli) and gram-positive (S. aureus) bacteria. The maximum zone of inhibition against gram-negative E. coli was calculated as 23.1 mm and 14.8 mm against S. aureus at a dilution of 16 mg ml−1 of cobalt oxide nanoparticle. This revealed the wide spectrum of antibacterial activity of the synthesized nanoparticle. It is suggested that root extract of cobalt oxide nanoparticles could be of great importance in pharmaceutical and medical science for their antimicrobial activity.

Antibacterial, Antibiofilm, and Anti-Quorum Sensing Potential of Novel Synthetic Compounds Against Pathogenic Bacteria Isolated From Chronic Sinusitis Patients.

Quorum sensing (QS) is a major controller of virulence and biofilm formation in pathogenic bacteria. The aim of the research was to screen novel synthetic compounds (18) from 2 series (Pyrazole and Diene dione) for quorum sensing and biofilm inhibitory potential against resistant pathogens isolated from patients with chronic sinusitis. Most of the compounds have documented zone of inhibition against Gram positive strains Staphylococcus aureus, Enterococcus faecalis and moderate activity against Gram negative Klebseilla pneumoniae and Proteus mirabilis in comparison with standard antibiotic. Compounds Q1 and Q7 have given the maximum zone of inhibition 18 and 20 mm with MICs 0.312 mg/mL and .156 mg/mL against S aureus and E faecalis, respectively. Some compounds were equally potent at inhibiting the formation of biofilm which later established by phase contrast microscopy. Regarding quorum sensing inhibition, the tested concentration of synthetic compound UA3 0.313 mg/mL inhibited violacein production without decreasing Chromobacterium pseudoviolaceum count which was significantly lower than determined MIC’s. It was depicted from the results that selected compounds exhibited low level of cytotoxicity toward human red blood cells. Hence, these findings revealed that most novel compounds were effective antibacterial, whereas compound UA3 has shared significant anti-quorum sensing potential against Chromobacterium pseudoviolaceum.