scholarly journals ANTIMICROBIAL ACTIVITY OF CALLYSPONGIA DIFFUSA (MARINE SPONGE) ASSOCIATED ENDOPHYTIC BACTERIA L STRAINS

Author(s):  
Vijayanand B. Warad ◽  
Prasanna Habbu ◽  
Rajesh Shastri

Objective: To screen the antimicrobial activity Of Callyspongia Diffusa (Marine Sponge) Associated Endophytic Bacterial Strains.Methods: We have isolated endophytic bacterias CDB-1 and CDB-2 from marine sponge Callyspongia diffusa and identified as Pseudomonas taiwanensis strain and Lysinibacillussphaericus strain respectively by the phylogenetic analysis. Fractions of CDB-1 and CDB-2 were screened for in vitro and in vivo antimicrobial activities against pathogenic bacteria and mycobacterium tuberculosis H37 RV strain by Minimum Inhibitory Concentration (MIC) method.Results: The lowest MIC against Kleibesella pnumoniae, Escherichia coli and Enterococcus feacalis was found to be 0.2 µg/ml and 0.4 µg/ml respectively for CDB-2. A significant antifungal activity was observed against Candida albicans (0.2-0.8 µg/ml) and Aspergillus niger (0.2-0.4 µg/ml). Further, Chloroform fraction of CDB-1 and ethyl acetate fraction of CDB-2 have shown significant anti-tubercular activity against the tested organism with MIC of 6.25µg/ml. This was supported by in vivo antimicrobial activity against K. Pneumonia infection in mice and least haemolytic activity against erythrocytes was observed. Compared to chloramphenicol.Conclusion: In this study, we have reported the marine natural species offer a rich source of bioactive metabolites that can exploit to develop novel, useful and potential therapeutic agents.

2019 ◽  
Vol 15 (1) ◽  
pp. 63-70
Author(s):  
Shiv Dev Singh ◽  
Arvind Kumar ◽  
Firoz Babar ◽  
Neetu Sachan ◽  
Arun Kumar Sharma

Background: Thienopyrimidines are the bioisoster of quinazoline and unlike quinazoline exist in three isomeric forms corresponding to the three possible types annulation of thiophene to the pyrimidine ring viz thieno[2,3-d] pyrimidine, thieno[3,2-d] pyrimidine and thieno[3,4-d]pyrimidine. Heterocyclic containing the thienopyrimidinone moiety exhibits various pronounced activities such as anti-hypertensive, analgesic and anti-inflammatory, antiviral, platelet aggregation inhibitory, antiprotozoal bronchodilatory, phosphodiesterase inhibitory, antihistaminic, antipsychotic and antimicrobial activity. Objective: Synthesis of novel 3(N,N-dialkylamino)alkyl/phenyl substituted thieno[2,3-d]pyrimidinones as H1-anti-histaminic and antimicrobial agents. Methods: A series of 3-[(N,N-dialkylamino)alkyl/phenyl]-2-(1H)thioxo-5,6,7,8-tetrahydrobenzo(b) thieno(2,3-d)pyrimidine-4(3H)-ones[4a-d], their oxo analogous [5a-d] and 3-[(N,N-dialkylamino)alkyl]- 2-chlorophenyl-5,6,7,8-tetrahydrobenzo(b)thieno(2,3-d)pyrimidine- 4 (3H)-ones[6a-d]derivative were synthesized from 2-amino-4,5,6,7-tetrahydrobenzo(b)thiophene-3-carboxylic acid by nucleophilic substitution of different N,N-dialkyl alkylene/phenylene diamines on activated 3-acylchloride moiety followed by cyclocondensation with carbon disulfide and ethanolic potassium hydroxide to get [4a-d] and in second reaction by condensation with 4-chlorobenzoyl chloride to get [6a-d] by single pot novel innovative route. The oxo analogous [5a-d] were prepared by treating derivatives [4a-d] with potassium permagnate in ethanolic KOH. The synthesized compound were evaluated for H1-antihistaminic and antimicrobial activities. Results: All synthesized compounds exhibited significant H1-antihistaminic activity by in vitro and in vivo screening methods and data were verified analytically and statistically. The compound 4a, 4b, 5a and 5b showed significant H1-antihistaminiic activity than the reference standard chlorpheniramine maleate. The compound 6d, 6c, 5c and 4c exhibited significant antimicrobial activity.


Author(s):  
KOSARAJU LAHARI ◽  
RAJA SUNDARARAJAN

Objective: Isatins have emerged as antimicrobial agents due to their broad spectrum of in vitro and in vivo antimicrobial activities. In addition, thiazolidinone also reported to possess various biological activities particularly antimicrobial activity. Due to the importance, we planned to synthesize compounds with isatin functionality coupled with thiazolidinone as possible antitubercular and antimicrobial agents which could furnish better therapeutic results. Methods: In vitro Mycobacterium tuberculosis method and agar streak dilution test are used to estimate antitubercular and antimicrobial potency of title analogs, respectively. Minimum inhibitory concentration of entire title compounds was determined against all tested microorganism such as M. tuberculosis, four Gram-positive, three Gram-negative bacteria, and two fungi. Results: A series of new thiazolidinone substituted Schiff and Mannich bases of 5-nitroisatins were designed and synthesized by a multistep synthesis from isatin. Structures of synthesized compounds are characterized using Fourier-transform infrared, proton nuclear magnetic resonance, mass spectroscopy, and bases of elemental analysis. Mild to good antitubercular and antimicrobial activity was showed by synthesized 5-nitroisatin analogs. The relationship between the biological activity and the functional group variation of the tested compounds was discussed. Conclusion: 3-(4-(3-(4-Aminophenyl)-4-oxothiazolidin-2-yl)phenylimino)-1-((dimethyl amino)methyl)-5-nitroindolin-2-one 6 and 3-(4-(3- (2-aminophenyl)-4-oxothiazolidin-2-yl)phenylimino)-1-((dimethylamino)methyl)-5-nitroindolin-2-one 13 were found to be the most potent compounds of this series which might be extended as a novel class of antimicrobial agents.


2020 ◽  
Vol 12 (1) ◽  
pp. 101-109
Author(s):  
H. Algarni ◽  
Ibrahim Alshahrani ◽  
Essam H. Ibrahim ◽  
Refaat A. Eid ◽  
Mona Kilany ◽  
...  

A novel 40P2O5–20Na2O–10Ca(OH)2–20CaCl2–6.0ZnO–2.0BaF2–2.0TiO2 (BGBaFTi) bioglasses is prepared. The reaction of the glasses in SBF solution is characterized by XRD and SEM indicated that the carbonate hydroxyapatite has formed rapidly on the glasses. BGBaFTi bioglasses was tested for its antimicrobial activity, anti-proliferative/cytotoxicity against normal and activated splenic cells in vitro and in vivo. This results showed that BGBaFTi has antimicrobial activities against Gram negative and positive bacteria as well as fungi. We found that the antimicrobial activity of nanoparticles of BGBaFTI is high than the normal powder of it. Moreover BGBaFTi (powder and nanoparticle) with cytotoxic effect on normal splenic cells was investigated. The products of activated splenic cells did not cause any changes in the structure of BGBaFTi. It did not cause any acute cytotoxicity or lysis to RBCs which was not affected by lytic products of immune cells. The bioactivity and biocompatibility of the present glasses use it a good potential candidate in the field of tissue engineering.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Amy B. Howell ◽  
Doris H. D'Souza

Pomegranates have been known for hundreds of years for their multiple health benefits, including antimicrobial activity. The recent surge in multidrug-resistant bacteria and the possibility of widespread global virus pandemics necessitate the need for additional preventative and therapeutic options to conventional drugs. Research indicates that pomegranates and their extracts may serve as natural alternatives due to their potency against a wide range of bacterial and viral pathogens. Nearly every part of the pomegranate plant has been tested for antimicrobial activities, including the fruit juice, peel, arils, flowers, and bark. Many studies have utilized pomegranate peel with success. There are various phytochemical compounds in pomegranate that have demonstrated antimicrobial activity, but most of the studies have found that ellagic acid and larger hydrolyzable tannins, such as punicalagin, have the highest activities. In some cases the combination of the pomegranate constituents offers the most benefit. The positive clinical results on pomegranate and suppression of oral bacteria are intriguing and worthy of further study. Much of the evidence for pomegranates’ antibacterial and antiviral activities against foodborne pathogens and other infectious disease organisms comes fromin vitrocell-based assays, necessitating further confirmation ofin vivoefficacy through human clinical trials.


2015 ◽  
Vol 9 (1) ◽  
pp. 61-66 ◽  
Author(s):  
Gundega Gulbe ◽  
Anda Valdovska ◽  
Vaira Saulite ◽  
Jevgenijs Jermolajevs

Probiotic lactic acid bacteria have a great potential to control bovine mastitis as well as they are favourable choice to treat many infectious diseases of human. These bacteria are well known as having many properties which make them beneficial to control pathogenic microorganisms. These include, the ability to adhere to cell, the reduction of pathogenic bacteria adherents, the co–aggregation, the production of organic acids, hydrogen peroxide, bacteriocin and etc., to be safe and non–pathogenic, which antagonize pathogenic microorganisms. However, each strain must be well identified and characterized in vitro before using for disease treatment. The aim of the present study was to screen three kind of test suspensions: TS1, TS2 and TS3, which contains probiotic lactic acid bacterium Lactobacillus helveticus or its natural glycopeptides, and other natural immunomodulators, in order to investigate which content were the most effective in inhibiting several mastitis causing bacteria in dairy cattle: coagulase–positive Staphylococcus aureus, coagulase–negative staphylococci S. haemolyticus, S. saprophyticus, S. simulans, S. vitulinus, and Gram–negative bacteria Citrobacter freundii and Serratia liquefaciens. Test suspensions TS1, TS2 and TS3 were adjusted by pH 6.3, then tested in vitro by well diffusion assay to determine their antimicrobial effect against bacteria. Furthermore haemolytic activity of applied test suspensions were determined. In results TS1 (9-13 mm) and TS2 (10-15 mm) showed the inhibition effect on four of eight tested bacterial strains, whereas TS3 did not displayed any antimicrobial effect. TS2 have a greatest antimicrobial activity as they resulted in the largest inhibition zones.


mBio ◽  
2016 ◽  
Vol 7 (5) ◽  
Author(s):  
Lillian J. Juttukonda ◽  
Walter J. Chazin ◽  
Eric P. Skaar

ABSTRACT During infection, bacterial pathogens must adapt to a nutrient metal-limited environment that is imposed by the host. The innate immune protein calprotectin inhibits bacterial growth in vitro by chelating the divalent metal ions zinc (Zn 2+ , Zn) and manganese (Mn 2+ , Mn), but pathogenic bacteria are able to cause disease in the presence of this antimicrobial protein in vivo. One such pathogen is Acinetobacter baumannii , a Gram-negative bacterium that causes pneumonia and bloodstream infections that can be complicated by resistance to multiple antibiotics. A. baumannii inhibition by calprotectin is dependent on calprotectin Mn binding, but the mechanisms employed by A. baumannii to overcome Mn limitation have not been identified. This work demonstrates that A. baumannii coordinates transcription of an NRAMP family Mn transporter and a urea carboxylase to resist the antimicrobial activities of calprotectin. This NRAMP family transporter facilitates Mn accumulation and growth of A. baumannii in the presence of calprotectin. A. baumannii is found to utilize urea as a sole nitrogen source, and urea utilization requires the urea carboxylase encoded in an operon with the NRAMP family transporter. Moreover, urea carboxylase activity is essential for calprotectin resistance in A. baumannii . Finally, evidence is provided that this system combats calprotectin in vivo , as deletion of the transporter impairs A. baumannii fitness in a mouse model of pneumonia, and this fitness defect is modulated by the presence of calprotectin. These findings reveal that A. baumannii has evolved mechanisms to subvert host-mediated metal sequestration and they uncover a connection between metal starvation and metabolic stress. IMPORTANCE Acinetobacter baumannii is a bacterium that causes bloodstream, wound, urinary tract, and pneumonia infections, with a high disease burden in intensive care units. Treatment of A. baumannii infection is complicated by resistance to most antibiotics in use today, and resistance to last-resort therapies has become commonplace. New treatments for A. baumannii infection are desperately needed, but our current understanding of the bacterial factors required to cause infection is limited. We previously found that the abundant innate immune protein calprotectin inhibits the growth of A. baumannii by withholding essential metals . Despite this, A. baumannii is still able to infect wild-type mice, which produce calprotectin during infection. Here, we identify factors employed by A. baumannii during infection to overcome calprotectin-mediated metal sequestration. Moreover, we expose a connection between metal starvation and metabolism that may be a “chink in the armor” of A. baumannii and lead to new treatment options.


Author(s):  
H. Tkachenko ◽  
L. Buyun ◽  
Z. Osadovskyy ◽  
M. Truhan ◽  
Ye. Sosnowski ◽  
...  

In the current investigation, screening of ethanolic extract obtained from Ficus lyrata leaves against pathogenic bacteria has been done in order to assess the antimicrobial activity aimed at detecting new sources of antimicrobial agents. The antimicrobial activity of the extract was determined using agar disc diffusion method. The antibacterial activity of leaf extract of F. lyrata was tested against human pathogenic bacteria — both Gram-positive (Staphylococcus aureus, methicillin-resistant S. aureus and Streptococcus pneumoniae) and Gram-negative strains (Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli). The results of this study provide evidence that the ethanolic extract of F. lyrata leaves has a mild antimicrobial activities, apparently, attributed to the presence of various secondary metabolites, which confirm the traditional use of this plant for the treatment of diseases caused by pathogens. These data allow us to suggest that the extracts of F. lyrata can be used to discover antibacterial substances for developing new pharmaceuticals to control clinically important pathogens responsible for severe disorders.


Author(s):  
Juliane Maria dos Santos Silva ◽  
Jackson Roberto Guedes da Silva Almeida ◽  
Cristiane dos Santos Cerqueira Alves ◽  
Daniel Amando Nery ◽  
Livia Maria Oliveira Damasceno ◽  
...  

Introduction: Nowadays, several bacteria have acquired resistance to available antimicrobial agents making necessary the search for new therapeutic alternatives. Plectranthus amboinicus L. is a succulent and aromatic herb, popularly known as thick leaf mint, used in popular medicine for the treatment of colds, digestive diseases, asthma, headache and to fight pathogenic bacteria activity. In view the antimicrobial activity of P. amboinicus this study had as aim to review publications involving researches about antimicrobial activity of this species. Materials and Methods: For this, PubMed, Scopus, Science Direct and Scielo databases were consulted in November 2020 using the keywords Plectranthus amboinicus and antimicrobial activity. In vitro and/or in vivo studies on the antimicrobial activity of the species in the last 10 years were considered. Results: The main microorganisms evaluated were: Klebsiella pneumoniae, Mycobacterium tuberculosis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and some Candida species. The essential oils had carvacrol, germacrene D, thymol and camphor as main constituents. Most studies evaluated the antimicrobial activity using broth dilution and agar diffusion methods. In most studies essential oil, extracts and/or isolated substances showed significant antimicrobial activity. Synergistic activity was also observed through association with antibiotics. Conclusion: P. amboinicus has therapeutic potential for antimicrobial treatments and can be an alternative to the treatment of resistant microorganisms and that further in vivo and clinical studies with the species are still needed.


2012 ◽  
Vol 7 (12) ◽  
pp. 1934578X1200701 ◽  
Author(s):  
Niko S. Radulović ◽  
Milan B. Stojković ◽  
Snežana S. Mitić ◽  
Pavle J. Randjelović ◽  
Ivan R. Ilić ◽  
...  

In this study we evaluated in vitro (radical scavenging) and in vivo (hepatoprotective effect) antioxidant activities and antimicrobial properties of the extracts of the above- and underground parts of Geranium macrorrhizum L. (Geraniaceae), an ethnopharmacologically renowned plant species. The antioxidant activity and total phenol and flavonoid contents of four different solvent extracts were evaluated by seven different methods. The methanol extracts, administered i.p. to rats (120-480 mg/kg), were evaluated for hepatoprotective activity in a CCl4-induced hepatotoxicity model. The same extracts were tested for antimicrobial activity against seven bacterial and two fungal species. The administered methanol extracts with the highest antioxidant potential showed a significant dose-dependent hepatoprotective action against CCl4-induced liver damage in both decreasing the levels of liver transaminases and bilirubin and in reducing the extent of morphological malformations of the liver. The leaf methanol extract displayed a very strong antibacterial activity, especially against Staphylococcus aureus, with low minimal inhibitory and bactericidal concentrations. These results justify the frequent use of this plant species in folk medicine. Besides the known astringent effect, one can expect that the observed antimicrobial activity against several human pathogens contributes to the wound healing properties of this plant.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Nathan das Neves Selis ◽  
Hellen Braga Martins de Oliveira ◽  
Hiago Ferreira Leão ◽  
Yan Bento dos Anjos ◽  
Beatriz Almeida Sampaio ◽  
...  

Abstract Background Probiotics are important tools in therapies against vaginal infections and can assist traditional antibiotic therapies in restoring healthy microbiota. Recent research has shown that microorganisms belonging to the genus Lactobacillus have probiotic potential. Thus, this study evaluated the potential in vitro probiotic properties of three strains of Lactiplantibacillus plantarum, isolated during the fermentation of high-quality cocoa, against Gardnerella vaginalis and Neisseria gonorrhoeae. Strains were evaluated for their physiological, safety, and antimicrobial characteristics. Results The hydrophobicity of L. plantarum strains varied from 26.67 to 91.67%, and their autoaggregation varied from 18.10 to 30.64%. The co-aggregation of L. plantarum strains with G. vaginalis ranged from 14.73 to 16.31%, and from 29.14 to 45.76% with N. gonorrhoeae. All L. plantarum strains could moderately or strongly produce biofilms. L. plantarum strains did not show haemolytic activity and were generally sensitive to the tested antimicrobials. All lactobacillus strains were tolerant to heat and pH resistance tests. All three strains of L. plantarum showed antimicrobial activity against the tested pathogens. The coincubation of L. plantarum strains with pathogens showed that the culture pH remained below 4.5 after 24 h. All cell-free culture supernatants (CFCS) demonstrated activity against the two pathogens tested, and all L. plantarum strains produced hydrogen peroxide. CFCS characterisation in conjunction with gas chromatography revealed that organic acids, especially lactic acid, were responsible for the antimicrobial activity against the pathogens evaluated. Conclusion The three strains of L. plantarum presented significant probiotic characteristics against the two pathogens of clinical importance. In vitro screening identified strong probiotic candidates for in vivo studies for the treatment of vaginal infections.


Sign in / Sign up

Export Citation Format

Share Document