scholarly journals Effect of Culture Medium Incorporated with Ocimum sanctum Extract in Enhancing Anti-MRSA activity of Endophytic Fungus, Lasiodiplodia pseudotheobromae

2021 ◽  
Author(s):  
Mohd Taufiq Mat Jalil ◽  
Nurul Aili Zakaria ◽  
Darah Ibrahim
Keyword(s):  
Plant Extract ◽  
Endophytic Fungus ◽  
Culture Medium ◽  
Inhibition Zone ◽  
Bactericidal Effect ◽  
Ocimum Sanctum ◽  
Bacterial Cells ◽  
Minimal Inhibition Concentration ◽  
Fungal Extract ◽  
Time Kill

The effect of incorporating plant extract in the culture medium on anti-MRSA activity of Lasiodiplodia pseudotheobromae IBRL OS-64, was investigated in the present study. On disk diffusion assay, the ethyl acetate fungal extract from culture medium supplemented with host plant extract (HPE) of Ocimum sanctum leaves demonstrated good anti-MRSA activity with a diameter inhibition zone of 22.6±0.6 mm. Meanwhile, the minimal inhibition concentration (MIC) values of the extract from YES broth and YES broth incorporated with HPE were 1000 µg/mL and 250 µg/mL, respectively. The MBC values were 8000 µg/mL and 500 µg/mL, respectively. The YES + HPE extracts exerted bactericidal effect against the test bacteria since the MBC/MIC ratio was less than or equal to 4. The time-kill study revealed a 90% of growth reduction of MRSA ATCC 33591 after 16 h exposure to the fungal extract cultured in YES + HPE. Ironically, for fungal extract grown in YES broth, time-kill curve showed a regrowth pattern of bacterial cells after 24 h exposed to the extract. Therefore, the present study suggested that the addition of HPE in the culture medium could enhance the anti-MRSA activity of endophytic fungus, L. pseudotheobromae IBRL OS-64 against MRSA ATCC 33591.

scholarly journals ANTI-MRSA OF THE ETHYL ACETATE CRUDE EXTRACT FROM LASIODIPLODIA PSEUDOTHEOBROMAE IBRL OS-64, AN ENDOPHYTIC FUNGUS ISOLATED FROM LEAF OF OCIMUM SANCTUM LINN

2018 ◽  
Vol 10 (8) ◽  
pp. 50 ◽  
Author(s):  
Taufiq M. M. J. ◽  
Darah I.
Keyword(s):  
Cell Wall ◽  
Cell Membrane ◽  
Ethyl Acetate ◽  
Crude Extract ◽  
Endophytic Fungus ◽  
Pathogenic Bacteria ◽  
Ocimum Sanctum ◽  
Minimal Bactericidal Concentration ◽  
Electron Microscopic ◽  
Time Kill

Objective: To investigate the effects of ethyl acetate crude extract of an endophytic fungus, L. pseudotheobromae IBRL OS-64 which was isolated from leaf of Ocimum sanctum against the growth of methicillin-resistant Staphylococcus aureus (MRSA)., a common pathogenic bacteria to human.Methods: Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined. Time-kill assay was used to examine the effect of the extract on the MRSA growth profile. The effects of the extract on the ultrastructure of MRSA cells were analyzed by scanning electron microscopic (SEM) study.Results: The results obtained from this study showed the fungal ethyl acetate crude extract exhibited a strong bactericidal effect on MRSA where the ratio of MBC/MIC was 2 and less than 4. The MIC and MBC values were 125.0 and 250.0 µg/ml, respectively. The time-kill study revealed that the bacteriocidal activity of the extract was both concentration and time-dependent. After 12 h treatment, the interaction of extract with MRSA cells resulted in the formation of dents, cavity or small dimples on the cell surface, indicating disintegration of the cell wall and cell membrane that resulting in leakage of their cytoplasmic contents, and ultimately cell death.Conclusion: The ethyl acetate crude extract of L. pseudotheobromae IBRL OS-64 showed a significant anti-MRSA activity and principally affected the cell wall and the cell membrane of the growing MRSA cells. This is the first report on L. pseudotheobromae, an endophytic fungus isolated from medicinal herb, Ocimum sanctum Linn.

Production of vincristine and vinblastine by the endophytic fungus Botryosphaeria laricina strain (CRS1) is dependent on stimulating factors present in Catharanthus roseus

2020 ◽  
Vol 10 ◽  
Author(s):  
Chamara Janaka Bandara ◽  
Asitha Siriwardhana ◽  
D. Nedra Karunaratne ◽  
B. M. R. Bandara ◽  
A. Wickramasinghe ◽  
...  
Keyword(s):  
Endophytic Fungi ◽  
Catharanthus Roseus ◽  
Plant Extract ◽  
Endophytic Fungus ◽  
Culture Medium ◽  
Vinca Alkaloid ◽  
Vinca Alkaloids ◽  
Alkaloid Production ◽  
Active Components ◽  
Aerial Parts

Aims: To isolate vinca alkaloid producing endophytic fungi from Catharanthus roseus and the evaluation of the factors which enhance the vincristine production. Background: An endophytic fungus Botryosphaeria laricina (CRS1) isolated from Catharanthus roseus demonstrated vinca alkaloid production under certain conditions. Method: Fungal isolates from C. roseus were grown in liquid culture and screened for alkaloid production. The strain (CRS1) producing catharanthine was sequenced and matched with GenBank. This isolated strain was studied for production of vinca alkaloids and the conditions required for vincristine and vinblastine production. Results: Eight endophytic fungi were isolated from the fresh aerial parts of C. roseus. Only CRS1, demonstrated catharanthine production. DNA sequencing of CRS1 gave a 100% match with the GenBank accession number, KC509580.1, which is related to the Botryosphaeria laricina strain JAS6. CRS1 produced only catharanthine when cultured in Czapek’s peptone liquid medium (CZ). Addition of C. roseus fresh plant extract (8.0 mL) to the culture medium (4.0 L) stimulated production of catharanthine (3.2 mg), catharanthinic acid (0.3 mg), N-demethyl-vinblastine (0.3 mg), vinblastine (2.8 mg) and vincristine (2.4 mg). However, if the added plant extract was preheated (80 ˚C, for 15 min), no vinca alkaloids appeared other than catharanthine. To identify the active fractions of the plant extract stimulating the vinca alkaloid production, the extract was dialyzed in buffer at 4 ˚C through 20 kDa MW cutoff membrane to separate into two fractions of molecules above and below 20 kDa MW .Only the fraction containing molecules above 20 kDa was able to transform catharanthine to vincristine and vinblastine. When the dialysis was performed in water instead of buffer, the larger fraction could only produce catharanthine and vinblastine. Other conditions such as the presence of light:dark (12:12 h), fructose (30.0 g L-1), glucose (30.0 g L-1), Cu2+ (0.1 mM) ions, L-tryptophan (0.1%) and succinic acid (1%) did not induce alkaloid production. Conclusions: The catharanthine producing fungal strain B. laricina (CRS1) could only produce the two vinca alkaloids vinblastine and vincristine from catharanthine in the presence of the active components larger than 20 kDa MW present in the plant extract of C. roseus,

scholarly journals Muscodor sp. IBRL OS-94, A Promising Endophytic Fungus of Ocimum sanctum with Antimicrobial Activity

2020 ◽  
Vol 27 (2) ◽  
pp. 268-280
Author(s):  
Mohd Taufiq Mat Jalil ◽  
Nabila Husna Hairudin ◽  
Darah Ibrahim
Keyword(s):  
Antimicrobial Activity ◽  
Endophytic Fungus ◽  
Disk Diffusion ◽  
Ocimum Sanctum ◽  
Gram Positive ◽  
Gram Negative ◽  
Fungal Extract ◽  
Gram Positive Bacteria ◽  
Agar Plug ◽  
Diffusion Assay

Background: An endophytic fungus, Muscodor sp. IBRL OS-94 isolated from the leaf of Ocimum sanctum was believed to possess significant antimicrobial activity and several assays were carried out to evaluate its pharmaceutical potential. Methods: Agar plug diffusion and the disk diffusion assays were performed to evaluate the antimicrobial activity of the fungal extract. Also, the broth microdilution assay was done to investigate the minimum inhibitory concentration (MIC) of the fungal extract. Meanwhile, the scanning electron microscope (SEM) was employed to observe the structural degeneration of the microbial cells treated to the extract. Results: The results revealed that fungal isolate showed favorable antimicrobial activity through agar plug diffusion assay and the disk diffusion assay demonstrated that most of the test microorganisms were susceptible to extracellular extract compared to extracellular extract. As for the MIC and MLC values, the extracellular fungal extract exerted a bactericidal/fungicidal effect against all five Gram-positive bacteria, four Gram-negative bacteria, one yeast, and none of the test fungi. Meanwhile, the intracellular fungal extract exhibited bactericidal/fungicidal activity against three Gram-positive bacteria, one Gram-negative bacterium, and one yeast. The structural degeneration study via SEM revealed that various cell abnormalities including severe damage to the cell wall which led to microbial cell death. Conclusion: The present study suggests the fungal extract from Muscodor sp. IBRLOS-94 as an antimicrobial agent.

scholarly journals Peptide/β-Peptoid Hybrids with Activity against Vancomycin-Resistant Enterococci: Influence of Hydrophobicity and Structural Features on Antibacterial and Hemolytic Properties

2021 ◽  
Vol 22 (11) ◽  
pp. 5617
Author(s):  
Martin Vestergaard ◽  
Bolette Skive ◽  
Ilona Domraceva ◽  
Hanne Ingmer ◽  
Henrik Franzyk
Keyword(s):  
Membrane Integrity ◽  
Bactericidal Effect ◽  
Structural Features ◽  
Intrinsic Resistance ◽  
Minimal Inhibitory Concentrations ◽  
Ic50 Values ◽  
Assay Time ◽  
Vancomycin Resistant ◽  
Conventional Antibiotics ◽  
Time Kill

Infections with enterococci are challenging to treat due to intrinsic resistance to several antibiotics. Especially vancomycin-resistant Enterococcus faecium and Enterococcus faecalis are of considerable concern with a limited number of efficacious therapeutics available. From an initial screening of 20 peptidomimetics, 11 stable peptide/β-peptoid hybrids were found to have antibacterial activity against eight E. faecium and E. faecalis isolates. Microbiological characterization comprised determination of minimal inhibitory concentrations (MICs), probing of synergy with antibiotics in a checkerboard assay, time–kill studies, as well as assessment of membrane integrity. E. faecium isolates proved more susceptible than E. faecalis isolates, and no differences in susceptibility between the vancomycin-resistant (VRE) and -susceptible E. faecium isolates were observed. A test of three peptidomimetics (Ac-[hArg-βNsce]6-NH2, Ac-[hArg-βNsce-Lys-βNspe]3-NH2 and Oct-[Lys-βNspe]6-NH2) in combination with conventional antibiotics (vancomycin, gentamicin, ciprofloxacin, linezolid, rifampicin or azithromycin) revealed no synergy. The same three potent analogues were found to have a bactericidal effect with a membrane-disruptive mode of action. Peptidomimetics Ac-[hArg-βNsce-Lys-βNspe]3-NH2 and Oct-[Lys-βNspe]6-NH2 with low MIC values (in the ranges 2–8 µg/mL and 4–16 µg/mL against E. faecium and E. faecalis, respectively) and displaying weak cytotoxic properties (i.e., <10% hemolysis at a ~100-fold higher concentration than their MICs; IC50 values of 73 and 41 µg/mL, respectively, against HepG2 cells) were identified as promising starting points for further optimization studies.

scholarly journals Synergistic Interaction of Methanol Extract fromCanarium odontophyllumMiq. Leaf in Combination with Oxacillin against Methicillin-ResistantStaphylococcus aureus(MRSA) ATCC 33591

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Dayang Fredalina Basri ◽  
Vimashiinee Sandra
Keyword(s):  
Inhibitory Concentration ◽  
Methanol Extract ◽  
Bactericidal Effect ◽  
Acetone Extract ◽  
Pharmacodynamic Interaction ◽  
Antistaphylococcal Activity ◽  
Preliminary Study ◽  
Canarium Odontophyllum ◽  
Time Kill ◽  
Acetone Extracts

Canarium odontophyllum(CO) Miq. has been considered as one of the most sought-after plant species in Sarawak, Malaysia, due to its nutritional and pharmacological benefits. This study aimed to evaluate the pharmacodynamic interaction of crude methanol and acetone extracts from CO leaves in combination with oxacillin, vancomycin, and linezolid, respectively, against MRSA ATCC 33591 as preliminary study has reported its potential antistaphylococcal activity. The broth microdilution assay revealed that both methanol and acetone extracts were bactericidal with Minimum Inhibitory Concentration (MIC) of 312.5 μg/mL and 156.25 μg/mL and Minimum Bactericidal Concentration (MBC) of 625 μg/mL and 312.5 μg/mL, respectively. Fractional Inhibitory Concentration (FIC) indices were obtained via the chequerboard dilution assay where methanol extract-oxacillin, acetone extract-oxacillin, methanol extract-linezolid, and acetone extract-linezolid combinations exhibited synergism (FIC index ≤ 0.5). The synergistic action of the methanol extract-oxacillin combination was verified by time-kill analysis where bactericidal effect was observed at concentration of 1/8 × MIC of both compounds at 9.6 h compared to oxacillin alone. As such, these findings postulated that both extracts exert their anti-MRSA mechanism of action similar to that of vancomycin and provide evidence that the leaves ofC. odontophyllumhave the potential to be developed into antistaphylococcal agents.

scholarly journals Antimicrobial Properties of 8-Hydroxyserrulat-14-en-19-oic Acid for Treatment of Implant-Associated Infections

2012 ◽  
Vol 57 (1) ◽  
pp. 333-342 ◽  
Author(s):  
Justyna Nowakowska ◽  
Hans J. Griesser ◽  
Marcus Textor ◽  
Regine Landmann ◽  
Nina Khanna
Keyword(s):  
Structural Changes ◽  
Treatment Options ◽  
Antimicrobial Properties ◽  
Bactericidal Effect ◽  
Mouse Tissue ◽  
Logarithmic Phase ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
Time Kill

ABSTRACTTreatment options are limited for implant-associated infections (IAI) that are mainly caused by biofilm-forming staphylococci. We report here on the activity of the serrulatane compound 8-hydroxyserrulat-14-en-19-oic acid (EN4), a diterpene isolated from the Australian plantEremophila neglecta. EN4 elicited antimicrobial activity toward various Gram-positive bacteria but not to Gram-negative bacteria. It showed a similar bactericidal effect against logarithmic-phase, stationary-phase, and adherentStaphylococcus epidermidis, as well as against methicillin-susceptible and methicillin-resistantS. aureuswith MICs of 25 to 50 μg/ml and MBCs of 50 to 100 μg/ml. The bactericidal activity of EN4 was similar againstS. epidermidisand its Δicamutant, which is unable to produce polysaccharide intercellular adhesin-mediated biofilm. In time-kill studies, EN4 exhibited a rapid and concentration-dependent killing of staphylococci, reducing bacterial counts by >3 log10CFU/ml within 5 min at concentrations of >50 μg/ml. Investigation of the mode of action of EN4 revealed membranolytic properties and a general inhibition of macromolecular biosynthesis, suggesting a multitarget activity.In vitro-tested cytotoxicity on eukaryotic cells was time and concentration dependent in the range of the MBCs. EN4 was then tested in a mouse tissue cage model, where it showed neither bactericidal nor cytotoxic effects, indicating an inhibition of its activity. Inhibition assays revealed that this was caused by interactions with albumin. Overall, these findings suggest that, upon structural changes, EN4 might be a promising pharmacophore for the development of new antimicrobials to treat IAI.

Hydrothermal Generation of 3-Dimensional WO3 Nanocubes, Nanobars and Nanobricks, Their Antimicrobial and Anticancer Properties

2021 ◽  
Vol 21 (10) ◽  
pp. 5337-5343
Author(s):  
Nilam Qureshi ◽  
Seungjae Lee ◽  
Ravindra Chaudhari ◽  
Pramod Mane ◽  
Jayant Pawar ◽  
...  
Keyword(s):  
Chemical Characterization ◽  
Growth Curves ◽  
Viable Cell ◽  
Inhibition Zone ◽  
Bacterial Cells ◽  
Hydrothermal Route ◽  
3 Dimensional ◽  
Anticancer Properties ◽  
Bacteria And Fungi ◽  
Micro Organisms

In our current endeavor, 3-dimensional (3D) tungsten oxide (WO3) nanostructures (nanocubes, nanobars and nanobricks) have been swiftly generated via hydrothermal route at 160 °C for 24 h. Physico-chemical characterization of the resultant powder revealed formation of WO3 nanostructures with predominantly faceted cube, brick and rectangular bar-like morphology. The present study was also aimed at exploring the antimicrobial and anticancer potential of WO3 nanostructures. Antimicrobial activity was tested against different micro-organisms viz., Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli and Aspergillus fumigatus. The antibacterial and antifungal activity was ascertained against these micro-organisms by measuring the diameter of inhibition zone in agar well diffusion test which revealed that the resultant WO3 nanostructures acted as excellent antibacterial agents against both bacteria and fungi but were more effective against the fungus, A. fumigatus. To examine the growth curves of bacterial cells, time kill assay was monitored for E. coli, against which significant antibacterial action of WO3 nanostructures was noted. The anti-cancer activity of WO3 nanostructures was found to be concentration-dependent against KB cell line by viable cell count method. In our pilot study, WO3 nanostructures suspension with concentration in the range of 10−1 to 10−5 mg/ml was found to kill KB cells effectively.

Antimicrobial Effects of Novel H2O2-Ag+ Complex on Membrane Damage to Staphylococcus aureus,Escherichia coli and Salmonella typhimurium

2021 ◽  
Author(s):  
Bing Han ◽  
Xiaoyu Han ◽  
Mengmeng Ren ◽  
Yilin You ◽  
Jicheng Zhan ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Hydrogen Peroxide ◽  
Staphylococcus Aureus ◽  
Salmonella Typhimurium ◽  
Membrane Damage ◽  
Bactericidal Effect ◽  
E Coli ◽  
Bacterial Cell Membrane ◽  
Time Kill ◽  
Environmental Disinfection

Diseases caused by harmful microorganisms pose a serious threat to human health. Safe and environment-friendly disinfectants are, therefore, essential in preventing and controlling such pathogens. This study aimed to investigate the antimicrobial activity and mechanism of a novel hydrogen peroxide and silver (H 2 O 2 -Ag + ) complex (HSC) in combatting Staphylococcus aureus ATCC 29213, Escherichia coli O157:H7 NCTC 12900 and Salmonella typhimurium SL 1344. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against S. aureus were found to be 0.014 % H 2 O 2 -3.125 mg/L Ag + , while 0.028 % H 2 O 2 -6.25 mg/L Ag + for both E. coli and S. typhimurium . Results of the growth curve assay and time-kill trial suggest that the HSC could inhibit the growth of the tested bacteria, as 99.9 % of viable cells were killed following treatment at the 1 MIC for 3 h. Compared with Oxytech D10 disinfectant (0.25 % H 2 O 2 -5 mg/L Ag + ), the HSC exhibited better antibacterial efficacy at a lower concentration (0.045 % H 2 O 2 -10 mg/L Ag + ). The mechanism of antibacterial action of HSC was found including the disruption of the bacterial cell membrane, followed by entry into the bacteria cell to reduce intracellular adenosine triphosphate (ATP) concentration, and inhibit the activity of antioxidases, superoxide dismutase (SOD) and catalase (CAT). The enhanced bactericidal effect of hydrogen peroxide combined with silver indicates a potential for its application in environmental disinfection, particularly in the food industry.

scholarly journals The anti-acetylcholinesterase, insecticidal and antifungal activities of the entophytic fungus Trichoderma sp. isolated from Ricinus communis L. against Locusta migratoria L. and Botrytis cinerea Pers.: Fr.

2020 ◽  
Vol 7 (1) ◽  
pp. 112-125
Author(s):  
Djamel Eddine Laib ◽  
Abdelmadjid Benzara ◽  
Salah Akkal ◽  
Chawki Bensouici
Keyword(s):  
Antifungal Activity ◽  
Botrytis Cinerea ◽  
Endophytic Fungus ◽  
Ricinus Communis ◽  
Locusta Migratoria ◽  
Inhibition Rate ◽  
Antifungal Activities ◽  
Fungal Extract ◽  
Ricinus Communis L ◽  
Trichoderma Sp

AbstractThis study was conducted to evaluate anti-acetylcholinesterase and insecticidal and antifungal activities of the endophytic fungus Trichoderma sp, isolated from Ricinus communis L. leaves, against Locusta migratoria L. and Botrytis cinerea Pers.: Fr.. To evaluate the insecticidal and antifungal activities, different concentrations of the fungal extract were applied against L. migratoria (0.2, 0.3, 0.4 g/l) and against B. cinerea (1, 2, 3 g/l). It was found that the mortality of the targeted insects was positively proportional to fungal extract concentration and time after exposure (24, 48, 72 hours). The concentration 0.4 g/l appeared to be the most effective after 72 hours with mortality rate of 56.52%. Regarding antifungal activity, the concentration 3 g/l was the most effective against B. cinerea after 7 days, with an inhibition rate of 92.06% (excellent antifungal activity). Moreover, it was found that at 4 ug/ml the fungal extract had a maximum inhibitory capacity of Ache of 80% for acetylcholenesterase. Preliminary phytochemical analyses revealed the presence of alkaloids, flavonoids, phenols and saponins. In addition the colony of this endophytic fungus produced chitinases and proteases, which explained its important antifungal and insecticidal activities.

Sign in / Sign up

Export Citation Format

Share Document