scholarly journals Protolichesterinic Acid: A Prominent Broad Spectrum Antimicrobial Compound from the Lichen Usnea albopunctata

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Nishanth Kumar Sasidharan ◽  
Sreerag Ravikumar Sreekala ◽  
Rajesh Lakshmanan ◽  
Jubi Jacob ◽  
Dileep Kumar Bhaskaran Nair Saraswathy Amma ◽  
...  

The aim of this study is to investigate the antimicrobial compounds present in the lichen Usnea albopunctata. Ethyl acetate extract was purified by silica gel column chromatography to obtain a major compound and the chemical structure was characterized by 1H-NMR, 13C-NMR, DEPT, 1H-1H COSY, HMQC, HMBC, UV, and HR-MS spectroscopic methods as protolichesterinic acid. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method and agar disc diffusion method against thirteen human pathogenic bacterial and four fungal strains. Protolichesterinic acid recorded significant broad spectrum antimicrobial property. The best antibacterial activity was recorded against K. pneumonia (0.25 μg/mL) and V. cholerae (0.5 μg/mL). Significant antifungal activity was recorded against T. rubrum (0.12 μg/mL), which is significantly better than the standard antifungal agent. Protolichesterinic acid is reported for the first time from Usnea albopunctata. Antifungal activity of protolichesterinic acid against medically important fungi is also reported for the first time. Thus the results of the present study suggest that protolichesterinic acid has significant antimicrobial activities and has the strong potential to be developed as an antimicrobial drug after further clinical evaluation.

2009 ◽  
Vol 53 (10) ◽  
pp. 4559-4562 ◽  
Author(s):  
Jun Ishikawa ◽  
Tetsuo Maeda ◽  
Itaru Matsumura ◽  
Masato Yasumi ◽  
Hidetoshi Ujiie ◽  
...  

ABSTRACT We have evaluated the antifungal activity of micafungin in serum by using the disk diffusion method with serum-free and serum-added micafungin standard curves. Serum samples from micafungin-treated patients have been shown to exhibit adequate antifungal activity, which was in proportion to both the applied dose and the actual concentration of micafungin measured by high-performance liquid chromatography. The antifungal activity of micafungin in serum was also confirmed with the broth microdilution method.


2017 ◽  
Vol 43 (3) ◽  
pp. 220-227
Author(s):  
Gülhan Turan-Zitouni ◽  
Betül Kaya Çavuşoğlu ◽  
Begüm Nurpelin Sağlık ◽  
Ulviye Acar Çevik

Abstract Objective: The advent of resistant pathogenic microorganisms against current antimicrobial drugs prompted scientists to investigate novel molecules with new mechanisms. In this paper, some new 2-[2-[4-(ethyl/phenyl)cyclohexylidene]hydrazinyl]-4-(4-substitutedphenyl)thiazole (2a–2o) derivatives were synthesized and studied for their antimicrobial activities. Materials and methods: The title compounds (2a–2o) were obtained via the reaction of 4-(ethyl/phenyl)cyclohexane-1-one with appropriate phenacyl bromide in ethanol at room temperature. The chemical structures of the compounds were elucidated by FT-IR, 1H-NMR, 13C-NMR, HRMS and elemental analysis. Antimicrobial activity of the compounds was measured by using broth microdilution method. Chloramphenicol and ketoconazole were used as reference drugs. Results: Among the synthesized compounds, 2-[2-(4-phenylcyclohexylidene)hydrazinyl]-4-phenylthiazole (2h) and 2-[2-(4-phenylcyclohexylidene)hydrazinyl]-4-(4-chlorophenyl)thiazole (2l) have been found to exhibit potency almost four-fold better than ketoconazole against C. albicans with MIC90 value of 1.95. Conclusion: The current study contributed to the knowledge of the antimicrobial activity of thiazole bearing compounds.


2020 ◽  
pp. 145-155

Brooder pneumonia is a common respiratory problem during brooding period of poultry. It is most frequently caused by Aspergillus fumigatus. Use of azole drugs for treatment and prophylaxis results in resistance. The aim of this study was to determine whether the phytochemicals of Eucalyptus globulus are modulating resistance in Aspergillus fumigatus. Lung samples n = 50 of dead broiler chicks were collected from different farms of Lahore. Out of 50 lung samples 28 % (14) were considered positive for Aspergillus fumigatus after observing their macroscopic, microscopic characteristics and by performing PCR by amplifying ITS1-ITS4 gene (597 base pairs) and RodA gene (313 base pairs). Kirby-Bauer disc diffusion test was performed 14 isolates (100 %) were resistant towards both Fluconazole and Ketoconazole whereas 11 (78.57 %) were resistant towards Itraconazole. Eucalyptus globulus leaves were collected, and these were identified. Three solvent extracts were prepared. Maximum yield was of ethanolic extract. Antifungal activity was evaluated by agar well diffusion method. Highest antifungal activity was shown by Eucalyptus globulus Ethanol followed by chloroform and hexane extract showed no activity against any isolate then minimum inhibitory concentration of plant extracts that previously showed antifungal activity against isolates were evaluated by broth microdilution method. Modulation effect was checked by combining antifungal drug one by one with subinhibitory concentration of plant extract evaluated previously by broth microdilution method. 5 isolates were subjected into this experiment which are all sensitive towards Eucalyptus globulus ethanol and chloroform extracts tested previously in agar well diffusion test and MIC values were also evaluated. It was concluded that when Itraconazole was combined with E. globulus Ethanol extract then resistance was modified. Data of modulation was analyzed by One-way ANOVA and it reported P value of <0.05. It was synergistic inhibitory effect when Itraconazole was combined with Eucalyptus globulus Ethanol extract.


2016 ◽  
Vol 11 (2) ◽  
pp. 1934578X1601100 ◽  
Author(s):  
Sarin Tadtong ◽  
Chompunut Puengseangdee ◽  
Suwapit Prasertthanawut ◽  
Tapanee Hongratanaworakit

The synergistic antimicrobial activities of blended essential oil preparations composed of eucalyptus, rosemary, patchouli, pine and cajuput oils were evaluated against various pathogenic microorganisms. They exhibited antimicrobial activity in the agar disc diffusion assay against the Gram-positive bacteria, Staphylococcus aureus and S. epidermidis, the Gram-negative bacteria, Escherichia coli an d Pseudomonas aeruginosa, and the yeast, Candida albicans. The minimum inhibitory concentration (MIC) of these preparations was evaluated by the broth microdilution method. We found that the best synergistic antibacterial preparation (the sum of fractional inhibitory concentrations, Σfic< 1) was eucalyptus, rosemary, and mineral oils (volume ratio 4:4:2) without patchouli, pine or cajuput oils added, while most preparations showed an antagonistic anticandidal effect (Σfic> 1). The blended essential oil preparations were characterized for their components by GC/MS, and contained 1,8-cineole as a major component. However, the preparation containing the highest amount of 1,8-cineole did not exhibit the best synergistic effect, which was shown by the preparation comprising the highest amount of α-pinene. Hence, we concluded that the differential antibacterial effect of either blended oil preparations or single/pure essential oils was influenced by the amount of α-pinene and the number of active components in either the blended preparations or single/pure essential oils.


2019 ◽  
Vol 16 (5) ◽  
pp. 415-423
Author(s):  
Metin Konus ◽  
Selahattin Aydemir ◽  
Can Yilmaz ◽  
Arif Kivrak ◽  
Aslihan Kurt Kizildogan ◽  
...  

5-bromo-2-(prop-2-yn-1-yloxy)benzaldehyde (compound 3) and 3,5-di-tert-butyl-2-(prop-2- yn-1-yloxy)benzaldehyde (compound 5) were synthesized via nucleophilic substitution reactions. Compound 5 showed higher antioxidant capacity with respect to compound 3 in all the four different antioxidant activity methods used. Moreover, in phosphomolybdenum assay, compound 5, with 1.1 proportion value, showed almost the same total antioxidant capacity compared to universal trolox standard. Furthermore, Broth microdilution method and agar disc diffusion tests demonstrated that the same compound also exhibited good antibacterial activity towards the bacteria Bacillus subtilis. Finally, both of the benzaldehyde compounds showed high antifungal activity against Aspergillus niger. In this study, compound 5 (IC50: 54.3 µg/ml) showed significant cytotoxic activity against breast adenocarcinoma cell line MCF-7 with respect to compound 3 (IC50: 173.4 µg/ml).


INDIAN DRUGS ◽  
2012 ◽  
Vol 49 (01) ◽  
pp. 24-32
Author(s):  
S. R. Pattan ◽  
◽  
S. H Kale ◽  
R. A. Mali ◽  
S. S. Dengale ◽  
...  

Millions of people are affected by infectious diseases caused by micro-organisms. Further the widespread microbial resistance had renewed the interest in quest for new antitubercular, antimicrobial & antifungal agents. The present study deals with synthesis & evaluation of some substituted 2-aminothiazole derivatives for their antitubercular, antimicrobial and antifungal activity. 2-aminothiazole derivatives were synthesized by treating substituted acetophenones with thiourea in presence of bromine to give 2-amino 4-substituted phenylthizole and then further treated with chloracetyl chloride to give 2-chloro-N-(4-substituted phenylthizole-2-yl)-acetamide which on refluxing with primary amine gives 15 derivatives. All the synthesized compounds were characterized by IR, H-NMR and elemental analysis.All the synthesized compounds were screened for their antibacterial activity against S. aureus and E. coli by using cup plate agar diffusion method. The activity was measured in terms of zone of inhibition and compared with standard drug ciprofloxacin, sulfonamide. The aminothiazole derivatives were evaluated for antitubercular activity and their result were compared with standard streptomycin.


2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Christiane Schineider Machado ◽  
João Benhur Mokochinski ◽  
Tatiana Onofre de Lira ◽  
Fátima de Cassia Evangelista de Oliveira ◽  
Magda Vieira Cardoso ◽  
...  

The chemical composition and biological activity of a sample of yellow propolis from Mato Grosso do Sul, Brazil (EEP-Y MS), were investigated for the first time and compared with green, brown, and red types of Brazilian propolis and with a sample of yellow propolis from Cuba. Overall, EEP-Y MS had different qualitative chemical profiles, as well as different cytotoxic and antimicrobial activities when compared to the other types of propolis assessed in this study and it is a different chemotype of Brazilian propolis. Absence of phenolic compounds and the presence of mixtures of aliphatic compounds in yellow propolis were determined by analysing1H-NMR spectra and fifteen terpenes were identified by GC-MS. EEP-Y MS showed cytotoxic activity against human tumour strain OVCAR-8 but was not active against Gram-negative or Gram-positive bacteria. Our results confirm the difficulty of establishing a uniform quality standard for propolis from diverse geographical origins. The most appropriate pharmacological applications of yellow types of propolis must be further investigated.


2013 ◽  
Vol 8 (9) ◽  
pp. 1934578X1300800 ◽  
Author(s):  
Dragoljub L. Miladinović ◽  
Budimir S. Ilić ◽  
Tatjana M. Mihajilov-Krstev ◽  
Dejan M. Nikolić ◽  
Olga G. Cvetković ◽  
...  

The composition and antimicrobial activity of the essential oil of Heracleum sibiricum L. (Apiaceae) was studied. The aerial part of plant was hydro-distilled and chemical composition of the essential oil was analyzed by GC and GC-MS. Forty-six compounds, corresponding to 95.12% of the total oil, were identified. Esters represented the major chemical class (69.55%) while the main constituents were octyl butanoate (36.82%), hexyl butanoate (16.08%), 1-octanol (13.62%) and octyl hexanoate (8.10%). Antibacterial activity of the essential oil and reference antibiotics against nine bacterial strains was tested by the broth microdilution method. The results of the bioassays showed that essential oil had slight antimicrobial activities against all tested microorganisms (MIC and MBC values were in the range of 2431.2 to 9724.8 μg/mL). Reference antibiotics were active in concentrations between 0.5 and 16.0 μg/mL. The results confirm that Gram-positive bacteria were more susceptible to the essential oil of H. sibiricum, in comparison with Gram-negative bacteria.


2013 ◽  
Vol 41 (1) ◽  
pp. 126 ◽  
Author(s):  
Hossam S. EL-BELTAGI ◽  
Mona H. BADAWI

The widespread use of medicinal plants for health purposes has increased dramatically due to their great importance to the public health. In this study levels of phenolic, flavonoid contents of Ginkgo biloba and Rosmarinus officinalis from Egypt were determined. HPLC was used to identify and quantify the phenolic compounds in selected plants. The plant extracts were evaluated for their antioxidant activities using various antioxidant methodologies, (i) scavenging of free radicals using 2, 2-diphenyl-1-picrylhydrazyl, (ii) metal ion chelating capacity, and (iii) scavenging of superoxide anion radical. The antimicrobial activity of both plant’s extracts were evaluated against a panel of microorganisms by using agar disc diffusion method. The total phenolic content (75.30 and 98.31 mg/g dry weight in G. biloba and R. officinalis, respectively) was significantly (p<0.05) different. Among the identified phenolic compounds, quercetin, kaempferol and caffeic acid were the predominant phenolic compounds in Ginkgo biloba, whereas carnosic acid, rosmarinic acid, narinigen and hispidulin were the predominant phenolic compound in Rosmarinus officinalis leaves. The antioxidant activity increased with the concentration increase. The R. officinalis was more active than G. biloba extract against Gram-negative bacteria. This study reveals that the consumption of these plants would exert several beneficial effects by virtue of their antioxidant and antimicrobial activities.


2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Diego F. Firmino ◽  
Theodora T. A. Cavalcante ◽  
Geovany A. Gomes ◽  
Nairley C. S. Firmino ◽  
Lucas D. Rosa ◽  
...  

To assess the activities of essential oils derived from the trunk bark of Cinnamomum zeylanicum (EOCz) and Cinnamomum cassia (EOCc) as well as cinnamaldehyde on bacterial biofilms of clinical interest. Antimicrobial activity was assessed by the broth microdilution method to determine minimum inhibitory concentrations (MICs). Antibiofilm activity was assessed by quantifying the biomass and determining the number of viable cells. The chemical composition of the essential oils was determined. The results showed that the major component of EOCz and EOCc was cinnamaldehyde. For the assayed substances, biofilm biomasses were reduced by up to 99.9%, and Streptococcus pyogenes, Pseudomonas aeruginosa, and Escherichia coli biofilms were sensitive to all of the concentrations and substances analysed. In cell viability tests, 2 mg/ml of cinnamaldehyde reduced the number of viable cells by 5.74 Log CFU/ml. EOCz, EOCc, and cinnamaldehyde exhibited antimicrobial and antibiofilm activities. This work describes substances with potential use against infections caused by bacterial biofilms.


Sign in / Sign up

Export Citation Format

Share Document