scholarly journals Fungi Diversity on Some Fruits and Biological Control using Two Plants Extracts

2021 ◽  
pp. 24-38
Author(s):  
Paul Ndip Besong ◽  
Tonjock Rosemary Kinge
Keyword(s):  
Biological Control ◽  
Moringa Oleifera ◽  
Fusarium Species ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Leaf Extracts ◽  
Safe Alternative ◽  
Ocimum Gratissimum ◽  
Fruit Samples

Fruits play an essential role in human nutrition by contributing the necessary growth factors like essential minerals and vitamins in human daily diet maintaining a good and normal health. But rot diseases caused by fungi cause severe losses of agricultural and horticultural crops every year. This work aimed to study fungi diversity on some fruits and carry out biological control using two plant extracts. A total of 17 infected fruit samples were collected from two local markets, small pieces of infected parts were inoculated on prepared plates of Potato Dextrose Agar. Incubation was done for 7 days and pure cultures were made, and pure isolated fungi were identified according to the recommended references. Ethanolic leaf extracts of Ocimum gratissimum and Moringa oleifera were evaluated for in vitro antifungal activities on Aspergillus and Fusarium species isolated from spoilt tomatoes and banana using the Agar Dilution Method. Eleven different fungi species comprising nine genera were isolated from the 17 fruits collected from the Nkwen and main markets of Bamenda. The fungi were identified as Saccharomyces cerevisiae, Aspergillus niger, Penicillium digitatum, Mucor sp, Fusarium sp, Mucor racemosus, Alternaria alternata, Colletotrichum sp, Nodulisporium sp, Fusarium oxysporum and Aspergillus flavus. There was some diversity in isolation frequency of the fungi from the fruits. Aspergillus, Penicillium, and Fusarium were the most common genera that colonized the fruits, with Aspergillus sp. found to be the most dominant fungi responsible for extensive damage of fruits. Ocimum gratissimum and Moringa oleifera leaf extracts had inhibitory activities on the test fungi. The diversity of the fungi identified in this study could be regarded as the most common causes of post-harvest deterioration of fruits. The findings of this study bring further evidence that Moringa oleifera and Ocimum gratissimum leaves extracts have the potential of becoming powerful and safe alternative means of fungi control on fruits instead of the harmful, expensive, environmentally unfriendly chemical fungicides.

scholarly journals Activity of Vitis vinifera Tendrils Extract Against Phytopathogenic Fungi

2015 ◽  
Vol 10 (6) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Daniele Fraternale ◽  
Donata Ricci ◽  
Giancarlo Verardo ◽  
Andrea Gorassini ◽  
Vilberto Stocchi ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Vitis Vinifera ◽  
Fusarium Species ◽  
Ethanolic Extract ◽  
Pathogenic Fungi ◽  
Phytopathogenic Fungi ◽  
Dilution Method ◽  
Vitis Vinifera L ◽  
Agar Dilution Method

The in vitro antifungal activity was determined of an ethanolic extract of Vitis vinifera L. tendrils (TVV) against ten plant pathogenic fungi, using the agar dilution method; activity was shown against all tested fungi. Fusarium species were the most sensitive with MIC values ranging from 250 to 300 ppm, while the basidiomycete fungus Rhizoctonia solani was the most resistant, with a MIC value of 500 ppm. Electrospray ionization tandem mass spectrometry (ESI-MSn) was used to obtain qualitative information on the main components of TVV. The high amount of polyphenolic compounds contained in TVV is likely to contribute significantly to its antifungal activity.

scholarly journals In vitro Assessment of Euclea crispa (Thunb.) Leaf Extracts against Campylobacter spp. and Escherichia coli - Common Diarrhoeal Agents

2018 ◽  
Vol 6 (4) ◽  
Author(s):  
Kazeem Adekunle Alayande ◽  
Carolina (H) Pohl ◽  
Anofi Omotayo Tom Ashafa
Keyword(s):  
Escherichia Coli ◽  
Mortality Rate ◽  
Ethyl Acetate ◽  
Leaf Extract ◽  
Total Mortality ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Leaf Extracts ◽  
Time Kill

Diarrhoea is a common childhood disease with high mortality rate. This study thus aimed at assessing effect of Euclea crispa leaf extract and its fractions against diarrhoea causing bacterial isolates and determining time-kill dynamics by each of the potent fractions. Susceptibility of each isolates was determined by agar well diffusion while the minimum bacteriostatic and bactericidal concentrations were determined by agar dilution method. Time-Kill dynamics was evaluated over a period of 120 min against Escherichia coli (1323) representing Gram negative isolates. The zones of inhibition exhibited by the leaf extract at 20 mg/ml range between 17±0.28 and 22±0.00 mm while that of the partitioned fractions at 10 mg/ml are between 14±0.00 and 22±0.00 mm. MICs of the leaf extract range between 0.31 and 2.50 mg/ml. The lowest MIC (0.08 mg/ml) is exhibited by the fractions partitioned into ethyl acetate, n-butanol and water while that of n-hexane and chloroform is 0.16 mg/ml. The lowest MBC exhibited by all the fractions is 0.31 mg/ml except that of the chloroform (1.25 mg/ml). Total mortality was achieved by the ethyl acetate fraction at a concentration of 2 × MIC after 120 min of contact time, meanwhile the mortality rate achieved by n-butanol, n-hexane, aqueous and chloroform fractions were 98, 94.6, 91.8 and 83.7% respectively under similar condition. This study showcase significant antidiarrhoeal potential of Euclea crispa leaf extracts and equally indicates a source of readily available therapeutic agent against diarrhoeal infection in South Africa and environs.

scholarly journals In-vitro Screening of Antimicrobial Activities of Ocimum gratissimum on Clinical Isolates

2019 ◽  
pp. 1-7
Author(s):  
Ifeanyi Onyema Oshim ◽  
Evelyn Ukamaka Urama ◽  
Oluwayemisi Odeyemi ◽  
Augustina Nkechi Olise ◽  
Sunday Odeyemi
Keyword(s):  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Ethanolic Extract ◽  
Antimicrobial Activities ◽  
Negative Control ◽  
Diffusion Method ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Ocimum Gratissimum

This study was undertaken to evaluate  the antimicrobial activities of crude  ethanol and methanol extracts of the leaves of Ocimum gratissimum L. (scent leaf) on Escherichia coli, Klebsiella  pneumoniae, Pseudomonas aeruginosa, Staphylococcus auerus and Candida albicans.The antimicrobial activities were carried out using  agar well diffusion method. The Minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) of the plant extracts on the test isolates were determined by the agar dilution method. Ciprofloxacin and fluconazole (positive controls) were used in comparison with crude extract of O. gratissimum leaves and also, Dimethyl sulfoxide (DMSO) was used as the negative control. The ethanolic extract of O. gratissimum showed antibacterial activity with the mean inhibitory zone diameter of 3 -7mm against S. auerus, 2 mm against E. coli, 2 – 12 mm against K. pneumoniae, 2 mm against P.aeruginosa. Ethanol and methanol crude extracts of O. gratissimum leaves   showed no effect on   C.albicans. O. gratissimum extracts showed the lower   antimicrobial activity than the commercially available antibiotics (ciprofloxacin and fluconazole). The minimum Inhibitory Concentration and Minimum Bactericidal Concentration of the extracts on the test organisms also increased in the following order; methanol < ethanol. Hence, this   extract could   only serve   as antibacterial agent in the management of bacterial infection because it has no antifungal activities on Candida isolates used in this study.

scholarly journals e-Pharmacophore model-guided design of potential DprE1 inhibitors: synthesis, in vitro antitubercular assay and molecular modelling studies

2021 ◽  
Author(s):  
Avinash Kumar ◽  
Revathi Rajappan ◽  
Suvarna G. Kini ◽  
Ekta Rathi ◽  
Sriram Dharmarajan ◽  
...  
Keyword(s):  
Pharmacophore Model ◽  
Antitubercular Activity ◽  
Stable Complex ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Standard Drug ◽  
Docking Score ◽  
Mycobacterium Tuberculosis H37rv ◽  
Cytotoxicity Studies

AbstractTuberculosis continues to wreak havoc worldwide and caused around 1.4 million deaths in 2019. Hence, in our pursuit of developing novel antitubercular compounds, we are reporting the e-Pharmacophore-based design of DprE1 (decaprenylphosphoryl-ribose 2′-oxidase) inhibitors. In the present work, we have developed a four-feature e-Pharmacophore model based on the receptor–ligand cavity of DprE1 protein (PDB ID 4P8C) and mapped our previous reported library of compounds against it. The compounds were ranked on phase screen score, and the insights obtained from their alignment were used to design some novel compounds. The designed compounds were docked with DprE1 protein in extra-precision mode using Glide module of Maestro, Schrodinger. Some derivatives like B1, B2, B4, B5 and B12 showed comparable docking score (docking score > − 6.0) with respect to the co-crystallized ligand. The designed compounds were synthesized and characterized. In vitro antitubercular activity was carried out on Mycobacterium tuberculosis H37Rv (ATCC27294) strain using the agar dilution method, and minimum inhibitory concentration (MIC) was determined. The compound B12 showed a MIC value of 1.56 μg/ml which was better than the standard drug ethambutol (3.125 μg/ml). Compounds B7 and B11 were found to be equipotent with ethambutol. Cytotoxicity studies against Vero cell lines proved that these compounds were non-cytotoxic. Molecular dynamic simulation study also suggests that compound B12 will form a stable complex with DprE1 protein and will show the crucial H-bond interaction with LYS418 residue. Further in vitro enzyme inhibition studies are required to validate these findings.

Antibacterial properties in-vitro of Mexican serviceberry extracts against dental biofilm species

2021 ◽  
pp. 1-16
Author(s):  
Erika-Alejandra Salinas-Peña ◽  
Martha Mendoza-Rodríguez ◽  
Claudia Velázquez-González ◽  
Carlo Eduardo Medina-Solis ◽  
América Patricia Pontigo-Loyola ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Antibacterial Properties ◽  
Fusobacterium Nucleatum ◽  
Positive Control ◽  
Dilution Method ◽  
Periodontal Pathogens ◽  
Leaf Extracts ◽  
Dental Biofilm ◽  
Biofilm Bacteria

BACKGROUND: The Mexican serviceberry, Malacomeles denticulata, have been used as a successful oral therapy by Mexican communities without enough scientific support. OBJECTIVE: To evaluate the M. denticulata extracts with selective antibacterial properties over dental biofilm bacteria. METHODS: Fruit, Leaf, and Stem of M. denticulata extracts were evaluated with micro-broth dilution method using ATCC bacteria. OD600 values had compared against each positive control (T-student-test). Anaerobically viability had confirmed by Colony-Forming-Units. Thin-Layer-Chromatography was used to identify the number of compounds and phytochemicals to identify secondary metabolites of the selected extracts. RESULTS: Streptococcus mutans showed Minimum-Bactericidal-Concentrations_(MBC) at 30 mg/mL to Fruit, Leaf, and Stem extracts. Periodontal-pathogens Aggregatibacter actinomycetemcomitans serotype b_(MBC = 30 mg/mL_p <  0.01); Fusobacterium nucleatum subsp. nucleatum_(MBC = 30 mg/mL_p<0.001); Parvimonas micra_(MBC = 15 mg/mL_NS); Porphyromonas gingivalis_(MBC = 30 mg/mL_NS); and Prevotella intermedia_(MBC = 3.75 mg/mL_NS) presented higher sensitivity to Leaf-Methanol, than the primary colonizers. Phytochemicals showed positive results to anthraquinones, coumarins, flavonoids, saponins, saponins steroids/triterpenoids, steroids/triterpenes, and tannins/phenols. CONCLUSION: We suggest the natural extracts of fruit and leaf of the Mexican serviceberry for the preventive use over the oral cariogenic or periodontal biofilm species, by their selective antibacterial properties against pathogenic species evaluated in-vitro, and due to the presence of antibacterial secondary metabolites identified as flavonoids and saponins of M. denticulata leaf extracts.

scholarly journals Antifungal and Antibacterial Metabolites from a French Poplar Type Propolis

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Séverine Boisard ◽  
Anne-Marie Le Ray ◽  
Anne Landreau ◽  
Marie Kempf ◽  
Viviane Cassisa ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Antifungal Activity ◽  
Antimicrobial Effect ◽  
Antibacterial Activities ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Gram Positive ◽  
Weak Activity ◽  
Agar Dilution

During this study, thein vitroantifungal and antibacterial activities of different extracts (aqueous and organic) obtained from a French propolis batch were evaluated. Antifungal activity was evaluated by broth microdilution on three pathogenic strains:Candida albicans, C. glabrata, andAspergillus fumigatus. Antibacterial activity was assayed using agar dilution method on 36 Gram-negative and Gram-positive strains includingStaphylococcus aureus. Organic extracts showed a significant antifungal activity againstC. albicansandC. glabrata(MIC80between 16 and 31 µg/mL) but only a weak activity towardsA. fumigatus(MIC80= 250 µg/mL). DCM based extracts exhibited a selective Gram-positive antibacterial activity, especially againstS. aureus(SA) and several of its methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) strains (MIC10030–97 µg/mL). A new and active derivative of catechin was also identified whereas a synergistic antimicrobial effect was noticed during this study.

scholarly journals IDENTIFICATION AND DETECTION OF BIOFILM PRODUCING STAPHYLOCOCCUS AUREUS AND ITS ANTIBIOGRAM ACTIVITIES

2021 ◽  
pp. 150-156
Author(s):  
SAPANA SHARMA ◽  
UPASHANA BHANDARI ◽  
YOGESH OLI ◽  
GANESH BHANDARI ◽  
SUNITA BISTA ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Disk Diffusion ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Methicillin Resistant ◽  
Clinical Specimens ◽  
Biofilm Production ◽  
Diffusion Technique ◽  
Almost All

Objectives: The main aim of this work is to determine the antibiogram profile of biofilm-producing Staphylococcus aureus from various clinical specimens of the patients. Methods: Various bacterial cultures of non-repeated clinical specimens from a total of 3388 patients were determined using standard microbiological and biochemical methods. Results: Out of 3388 only 604 (17.02%) displayed growth positive. A total of 65 (51.58%) S. aureus isolates were recovered, 25 (38.46%) were identified as methicillin-resistant S. aureus (MRSA) by Cefoxitin (30 μg) disk diffusion technique, of which majority were from pus/wound swab 22 (37.29%). The antibiogram of the isolates was analyzed by Kirby-Bauer disk diffusion technique analyzing Linezolid to be the most effective drug with susceptibility of 100% to both MRSA and methicillin-sensitive S. aureus, followed by vancomycin, tigecycline, and tetracycline. In vitro biofilm production by tissue culture plate (TCP) and Congo red agar method detected 52 (80%) and 25 (38.46%) as biofilm producers, respectively. TCP identified 2 (3.07%), 7 (10.76%), and 44 (67.69%) as strongly, moderately, and weakly adherent. About 30.7% of MRSA obtained were positive biofilm producers. The minimum inhibitory concentration value of Oxacillin for S. aureus by agar dilution method ranged from 0.025 μg/mL to 128 μg/mL. Conclusion: This study shows that biofilm production was more in methicillin-resistant strains and displayed a high degree of resistance to almost all groups of antibiotics.

Ginseng aqueous extract attenuates the production of virulence factors, stimulates twitching and adhesion, and eradicates biofilms of Pseudomonas aeruginosa

2011 ◽  
Vol 89 (6) ◽  
pp. 419-427 ◽  
Author(s):  
Misagh Alipour ◽  
Abdelwahab Omri ◽  
Zacharias E. Suntres
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Virulence Factors ◽  
Aqueous Extract ◽  
North American ◽  
American Ginseng ◽  
Antimicrobial Activities ◽  
Live Cells ◽  
Dilution Method ◽  
Agar Dilution Method

This study was carried out to examine the antimicrobial activity of the aqueous extract of Panax quinquefolius from North American ginseng (NAGE) root against Pseudomonas aeruginosa . The minimum inhibitory concentrations of reference and clinical isolates of Pseudomonas aeruginosa were measured by a standard agar-dilution method. At subinhibitory NAGE concentrations, the secretion of virulence factors, motility on agar, and adhesion to 96-well microplates were studied on the nonmucoid Pseudomonas aeruginosa O1 strain. At suprainhibitory concentrations, the activity of NAGE against mature biofilm complexes formed in the Calgary Biofilm Device and the Stovall flow cell were assessed. NAGE possessed an antibacterial activity against all the Pseudomonas aeruginosa strains at 1.25%–2.5% w/v. NAGE also significantly attenuated pyocyanin, pyoverdine, and lipase concentrations, stimulated twitching, and attenuated swarming and swimming motility. At 1.25% w/v, NAGE augmented adhesion, and at 5% w/v detached 1-day-old biofilms in microplates. The extract also eradicated 6-day-old mature biofilms (5% w/v), and fluorescence microscopy displayed a reduction of live cells and biofilm complexes compared with nontreated biofilms. These data suggest that the aqueous extract from North American ginseng possesses antimicrobial activities in vitro.

scholarly journals Radiometric studies of mycobacterium tuberculosis

1987 ◽  
Vol 29 (1) ◽  
pp. 18-25
Author(s):  
Edwaldo E. Camargo ◽  
Judith A. Kertcher ◽  
Marianne F. Chen ◽  
Patricia Charache ◽  
Henry N. Wagner Jr
Keyword(s):  
Palmitic Acid ◽  
Lauric Acid ◽  
Bacterial Suspension ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Experimental Conditions ◽  
Vitro Assay ◽  
Minimal Inhibitory Concentrations ◽  
Different Strains

An in vitro assay system that included automated radiometric quantification of 14CO2 released as a result of oxidation of 14C- substrates was applied for studying the metabolic activity of M. tuberculosis under various experimental conditions. These experiments included the study of a) mtabolic pathways, b) detection times for various inoculum sizes, c) effect of filtration on reproducibility of results, d) influence of stress environment e) minimal inhibitory concentrations for isoniazid, streptomycin, ethambutol and rifampin, and f) generation times of M. tuberculosis and M. bovis. These organisms were found to metabolize 14C-for-mate, (U-14C) acetate, (U-14C) glycerol, (1-14C) palmitic acid, 1-14C) lauric acid, (U-14C) L-malic acid, (U-14C) D-glucose, and (U-14C) D-glucose, but not (1-14C) L-glucose, (U-14C) glycine, or (U-14C) pyruvate to 14CO2. By using either 14C-for-mate, (1-14C) palmitic acid, or (1-14C) lauric acid, 10(7) organisms/vial could be detected within 24 48 hours and as few as 10 organisms/vial within 16-20 days. Reproducible results could be obtained without filtering the bacterial suspension, provided that the organisms were grown in liquid 7H9 medium with 0.05% polysorbate 80 and homogenized prior to the study. Drugs that block protein synthesis were found to have lower minimal inhibitory concentrations with the radiometric method when compared to the conventional agar dilution method. The mean generation time obtained for M. bovis and different strains of M. tuberculosis with various substrates was 9 ± 1 hours.

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