Synergistic anti–Staphylococcus aureus activity of amoxicillin in combination with Emblica officinalis and Nymphae odorata extracts

ObjectiveTo evaluate the antibacterial activity of Emblica officinalis Gaertn (E. officinalis; Family: Euphorbiaceae) seed and Nymphae odorata Aiton (N. odorata; Family: Nymphaeaceae) stamen extracts, alone and in combination, and in combination with amoxicillin (Ax) against Staphylococcus aureus (S. aureus).MethodsAntibacterial activity of ethanolic extracts of amla, E. officinalis, seed (AMS; 500 μg) and sapla, N. odorata, stamen (SAP; 500 μg) for 12 methicillin-resistant S. aureus (MRSA) isolates was determined following agar diffusion; in order to assess the combined antibacterial activity, AMS (250 μg) plus SAP (250 μg) were considered. The Ax (10 μg) activity alone and in combination with AMS (250 μg), and SAP (250 μg) was determined by disk diffusion. The zone diameters of inhibition (ZDI s) for the agents were recorded, and growth inhibitory indices (GII s) were calculated.ResultsThe MRSA isolates (n = 12) had AMS (500 μg) and SAP (500 μg) ZDI s of 12-19 mm and 21-24 mm, respectively. The ZDI s (range 24-27 mm) increased by 3-4 mm due to combined action of AMS (250 μg) and SAP (250 μg) indicating synergy between extracts for MRSA (GII 0.634-0.742). The MRSA isolates were resistant to Ax (ZDI: 8-11 mm), which in combination with AMS and SAP had synergistic effect, both due to increased ZDI [mean± SD = (3.5 ± 0.577) mm] and GII (0.631-0.894).ConclusionsThe data suggest that the plants, E. officinalis and N. odorata alone or in combination, are promising in the development of phytomedicines, which may be used, alone or in combination with the antibiotic, Ax, against MRSA infection.     

Antifungal activity of Ocimum sanctum Linn. (Lamiaceae) on clinically isolated dermatophytic fungi

ObjectiveTo assess antifungal activity of Ocimum sanctum leaves against dermatophytic fungi.MethodsAntifungal activity of Ocimum sanctum leaves was measured by 38 A NCCLS method. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of various extracts and fractions of Ocimum sanctum leaves were also determined.ResultsOcimum sanctum leaves possessed antifungal activity against clinically isolated dermatophytes at the concentration of 200 μg/mL. MIC and MFC were high with water fraction (200 μg/mL) against dermatophytic fungi used.ConclusionsOcimum sanctum has antifungal activity, and the leaf extracts may be a useful source for dermatophytic infections.     

In vitro antiplasmodial effect of ethanolic extracts of traditional medicinal plant Ocimum species against Plasmodium falciparum

ObjectiveTo identify the possible antiplasmodial compounds from leaf, stem, root and flower extracts of Ocimum canum (O. canum), Ocimum sanctum (O. sanctum) and Ocimum basilicum (O. basilicum).MethodsThe O. canum, O. sanctum and O. basilicum were collected from Ramanathapuram District, Tamil Nadu and the extraction was carried out in ethanol. The filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μg/mL) of leaf, stem, root and flower extracts of O. canum, O. sanctum and O. basilicum were tested for antiplasmodial activity against Plasmodium falciparum (P. falciparum). The potential extracts were also tested for their phytochemical constituents.ResultsThe leaf extract of O. sanctum showed excellent antiplasmodial activity (IC₅₀ 35.58 μg/mL) followed by leaf extract of O. basilicum (IC₅₀ 43.81 μg/mL). The leaf extract of O. canum, root extracts of O. sanctum and O. basilicum, the stem and flower extracts of all the three tested Ocimum species showed IC₅₀ values between 50 and 100 μg/mL. Statistical analysis reveals that, significant antiplasmodial activity (P <0.01) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes was also carried out and it shows that, there were no morphological changes in erythrocytes by the ethanolic extract of O. canum, O. sanctum and O. basilicum. The in vitro antiplasmodial activity might be due to the presence of alkaloids, glycosides, flavonoids, phenols, saponins, triterpenoids, proteins, resins, steroids and tannins in the ethanolic extracts of tested plants.ConclusionsThe ethanolic leaf extracts of O. sanctum possess lead compounds for the development of antiplasmodial drugs.     

Screening, phylogenetic analysis and antibiotic sensitivity pattern of Salmonella enterica serovar Typhi isolates from typhoid asymptomatic carriers

ObjectiveTo isolate the Salmonella enterica serovar Typhi (S. typhi) from asymptomatic typhoid carriers in the local population. To assess the antibiotic sensitivity and resistant pattern of S. typhi isolates against viable antibiotics and phylogenetic analysis of S. typhi isolates on the basis of 16S rDNA gene.MethodsS. typhi was isolated and identified based on the cultural characteristics on BSA (Bismuth Sulphite Agar), MacConkey agar, agglutination test with specific antiserum and phylogenetic analysis. S. typhi isolates were tested for sensitivity and resistant pattern with a number of viable antibiotics by disc diffusion method.ResultA total of 15 bile samples were collected from the food handlers to screen the typhoid asymptomatic carriers. Positive result was yielded for 3 out of 15 samples. S. typhi isolates showed resistant to amphicillin (100%), tetracyclin (100%), rifampicin (66.5%), ofloxacin (33.5%), cloxacillin (33.5%) and susceptibility to gentamycin (100%), amikacin (100%), chloramphenicol (100%), streptomycin (100%), kanamycin (100%), cprofloxacin (100%), amoxycillin (66.5%) and ofloxacin (66.5%).ConclusionsThis study demonstrates the outbreak of typhoid fever occurs through asymptomatic carrier. In addition, this study also reveals the occurrence of considerable drug resistant among the S. typhi isolates.     

Efficacy of fresh leaf extracts of Spondias mombin against some clinical bacterial isolates from typhoid patients

ObjectiveTo evaluate the phytochemical properties and antibacterial activity of methanol, acetone, ethanol and aqueous extracts of fresh leaves of Spondias mombin (S. mombin) on some clinical bacterial isolates.MethodsClean and fresh leaves of S. mombin were collected in Ondo, Southwestern Nigeria. The leaves were blended, extracted with methanol, acetone, ethanol and water. The extracts were evaporated to dryness using rotary evaporator and tested for the presence of saponins, tannins, cardiac glycoside, terpenoids, flavonoids, reducing sugars, volatile oils, alkaloids and glycoside. The extract were tested against Gram-negative bacteria Klebsiella pneumonia, Serratia marcescens, Salmonella typhi and Enterobacter aerogens; Gram-positive bacteria Staphylococcus aureus by observing the zones of inhibition using agar well diffusion assay.ResultsThe study showed that the leaves contained saponins, tannins, flavonoids, alkaloids and glycoside. All the solvent extracts showed activity against all the test bacteria. The methanol extract also showed the highest activity against Enterobacter aerogens, zone of diameter (15.00依1.89) mm, while the ethanol extract showed the highest activity against Staphylococcus aureus with zone of diameter (12.50依1.50) mm. The acetone extract showed the highest activity against Salmonella typhi, zone of diameter (17.50依0.29) mm followed by methanol extract showing zone of diameter (15.67依1.01) mm. The acetone extract showed the highest activity against Klebsiella pneumonia (15.17依0.67) mm, while the aqueous extract shows the highest activity against Serratia marcescens (14.67依2.68) mm. The minimum inhibitory concentration of the leaf extracts ranged between 10-90 mg/mL.ConclusionsThis study showed that the aqueous and organic solvents extract of fresh leaves of S. mombin has anti-microbial activity against all the tested organisms.     

Antibacterial activities of some Indian traditional plant extracts

ObjectiveTo evaluate the in vitro antibacterial activity of various solvent extracts of South Indian traditional medicinal plants Ocimum sanctum, Ocimum gratissimum, Aegle marmelos, and Adhatoda vasica leaves against clinical pathogens of human origin.MethodsThe antimicrobial activity of different solvents crude extract of four medicinal plants used in traditional Indian medicine was tested by disc diffusion method against five bacterial pathogens: Escherichia coli, Staphylococcus aureus, Salmonella typhi, Salmonella paratyphi and klebsiella pneumoniae.. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was determined for evaluating the potential plant extract.ResultsThe antibacterial results showed methanol extracts (0.4 g/ml) of Ocimum gratissimum and Ocimum sanctum showed maximum zone of inhibition (30 mm and 25.5 mm, respectively) against Salmonella typhi. MIC was tested at various concentrations from 0.625 mg/ml to 0.039 mg/ml for all the plant extracts. At the lowest concentration (0.039mg/ml) tested, methanol extracts of Ocimum gratissimum showed higher MIC against Salmonella typhi and Salmonella paratyphi where as the methanolic extracts of Ocimum gratissimum showed potent activity against Staphylococcus aureus at 0.078 mg/ml. Methanol extract (0.4 g/ml) of Aegle marmelos showed significant inhibitory activity of 22.5mm and MIC value of 0.156.mg/ml against E. coli strain. The Klebsiella spp was the most resistant strain of all and various concentrations Adhatoda vasica extract showed less activity against the tested pathogens.ConclusionsThe present screening result demonstrated that the Indian traditional medicinal plants Ocimum sanctum, Ocimum gratissimum, Aegle marmelos methanol leaf extract has potent antibacterial activity and the studied plants may be new source for novel antibacterial compound discovery for treating drugs resistant human pathogens.     

Antibacterial activity of various honey types of Algeria against Staphylococcus aureus and Streptococcus pyogenes

ObjectiveTo assess the in vitro antibacterial activity of honey from different geographical location on Gram negative organismes.MethodsDifferent concentrations (Undiluted honey, 10 %, 30%, 50% and 70% wt/vol) of honey were studied in vitro using Staphylococcus aureus (S. aureus) and Streptococcus pyogenes (S. pyogenes), briefly, two-fold dilutions of honey solutions were tested to determine the minimum inhibitory concentration (MIC) against each type of microorganism, followed by more assays within a narrower dilution range to obtain more precise MIC values. MICs were determined by both visual inspection and spectrophotometric assay at 620 nm. These honey samples were compared with standard antibiotics like ampicillin, penicillin G, amoxicillin, gentamycin, tobramycin, erythromycin and chloramphenicol was determined by the disc diffusion method.ResultsThe diameter of zone of the inhibition (ZDI) of honey has various concentrations tested for the isolates ranged 0–46 mm for S. aureus, 0–44 mm for S. pyogenes. While the MIC (%) ranged 12%-95%, 25%-73% respectively.ConclusionsAlgeria honey, in-vitro, possess antibacterial activity.     

Antimicrobial activity of the ethanolic and aqueous extracts of Salacia chinensis Linn. against human pathogens

ObjectiveTo investigate antimicrobial effects of ethanolic and aqueous extracts of Salacia chinensis (S. chinensis) Linn. against pathogenic bacteria and fungi.MethodsThe Staphylococcus aureus (S. aureus) (MTCC 96), Staphylococcus epidermidis (S. epidermidis) (MTCC 435), Bacillus subtilis (B. subtilis) (MTCC 121), Escherichia coli (E. coli) (MTCC 443), Klebsiella pneumoniae (K. pneumoniae) (MTCC 432), Proteus mirabilis (P. mirabilis) (MTCC 1429), Salmonella paratyphi A (S. paratyphi A) (MTCC 735), Salmonella typhimurium (S. typhimurium) (MTCC 98), Shigella flexneri (S. flexneri) (MTCC 1457) and Pseudomonas aeruginosa (P. aeruginosa) (MTCC 424), Candida albicans (C. albicans) (MTCC 183) and Cryptococcus neoformans (C. neoformans) (clinical isolate) were originally obtained from Microbial Type Culture Collection Centre, Institute of Microbial Technology, Chandigarh, India. Antimicrobial activity was carried out by disc diffusion and broth dilution methods against pathogens by using crude ethanolic and aqueous extracts.ResultsEthanolic extract of S. chinensis L. leaves showed significant antimicrobial activity against S. epidermidis (33.20 mm), C. albicans (30.40 mm) and C. neoformans (18.20 mm) mean values were documented. Aqueous extract of leaves showed significant inhibitory activity against C. neoformans (19.8 mm) and S. epidermidis (17.80 mm) were observed. Based on broth dilution method, the ethanolic extract of crude plant material showed the minimum inhibitory concentration (MIC) values against S. epidermidis, C. neoformans (256 μg/mL) and C. albicans (512 μg/mL), whereas the aqueous extract of S. chinensis L. leaves showed significant inhibitory activity against S. epidermidis (512 μg/mL) and C. neoformans (1024 μg/mL) were observed.ConclusionsThe present result revealed that ethanolic extract of S. chinensis L. possesses significant antifungal activity when compared as the antibacterial activities.     

Antibacterial activity of selected ethnomedicinal plants from South India

ObjectiveTo screen the antimicrobial potential of three ethnomedicinal plants Chassalia curviflora Thw. (C. curviflora), Cyclea peltata Hook. F. &; Thomson (C. peltata) and Euphorbia hirta L (E. hirta) used in folk medicines in Aarukani hills Kani tribe, Tamil Nadu, India against human bacterial pathogens.MethodsAntibacterial efficacy was performed by disc diffusion method against the pathogens viz., Escherichia coli (E. coli) (ATCC 35218), Staphylococcus aureus (S. aureus) (ATCC 6538), Salmonella typhi (S. typhi) (MTCC 733), Proteus vulgaris (P. vulgaris), Proteus mirabilis (P. mirabilis) and Streptococcus pyogenes (S. pyogenes) and incubated for 24 h at 37 °C.ResultsThe maximum degree of antibacterial activity was observed in C. peltata followed by C. curviflora. While E. hirta showed comparatively low degree of antibacterial activity. The methanolic extract of C. peltata showed the antibacterial activity against three pathogens viz., S. pyogenes, P. vulgaris and E. coli with the inhibition zones 12 mm, 10 mm and 9 mm, respectively. hexane extracts of C. peltata also showed the antibacterial activity against two selected pathogens viz., P. vulgaris and P. mirabilis with 15 mm and 12 mm of inhibition zones. All the three different concentrations (0.25, 0.50 &; 0.75 mg/mL) of methanolic extract of C. peltata show the inhibitory effect on the three susceptible bacteria S. pyogenes, P. vulgaris and E. coli with the maximum inhibition in the highest concentration (0.75 mg/mL). The methanolic and hexane extracts of C. curviflora exhibited the antibacterial activity against only one bacterium each i.e. P. vulgaris and S. typhi with the maximum zone of inhibition 13 and 11 mm respectively. The methanolic and hexane extracts of E. hirta exhibited the antibacterial activity against only one bacterium i.e. S. pyogenes with the maximum zone of inhibition 13 and 11 mm respectively.ConclusionsThe present investigation revealed that the C. curviflora, C. peltata and E. hirta are potentially good source of antibacterial agents and demonstrates the importance of such plants in traditional medicines.     

In-vitro anti-Mycobacterium tuberculosis effect of essential oil of Ocimum sanctum L. (Tulsi/Basil) leaves

Background/ObjectivesMycobacterium tuberculosis, the causative agent of tuberculosis has developed resistance to most of the available antimicrobials. Consequently, it is difficult to cure all the patients with tuberculosis and in future, the incidence of tuberculosis by drug resistant M. tuberculosis is likely to increase, worldwide. Therefore detection and development of new antimicrobials against M. tuberculosis is needed urgently.MethodsEssential oil from the leaves of Ocimum sanctum L (Tulsi/Basil) was obtained by hydro distillation. The anti-mycobacterial effect of essential oil was evaluated against H37Rv and nine clinical isolates of M. tuberculosis in the BD BACTEC MGIT instrument using different volumes of essential oil.ResultsThe essential oil inhibited the growth of H37Rv and all the nine clinical isolates of M. tuberculosis. The minimal inhibitory concentration of H37Rv was 3 μl (2.931 μg) and those of the clinical isolates of M. tuberculosis ranged from 1.5 μl (1.4655 μg) to 6 μl (5.862 μg).ConclusionThe Essential oil from the leaves of O. sanctum L.(Tulsi/Basil) has anti-M. tuberculosis effect in the in-vitro BD BACTEC MGIT method.     

Immunomodulating property of Ocimum sanctum by regulating the IL-2 production and its mRNA expression using rat's splenocytes

ObjectiveTo investigate the regulatory effect of aqueous extract of leaves of Ocimum sanctum on IL-2 cytokine production in vivo and in vitro, and the effect of leaves extract on general blood picture including T& B lymphocytes.MethodsFor in vivo studies albino Wistar rats were treated with aqueous crude leaves extract of Ocimum sanctum for 20 consecutive days. Spleen cells were harvested and assayed for IL-2 production by using sandwich enzyme-linked immunosorbent assay (ELISA) and mRNA expression methods. For in vitro study aqueous Ocimum sanctum leaves extract = in different concentrations (25–500 μg/mL) was added into culture plates containing ConA stimulated splenocytes. To study the overall effect on blood picture, density gradient purified lymphocytes analysis and conventional methodology for total and differential leukocyte count and hemoglobin level were also done.ResultsIt indicated that the rats treated with Ocimum sanctum leaves extract had significantly enhanced (P < 0.001) ability of spleen cells to secrete IL-2. Investigation in vitro also showed regulation of IL-2 production. Blood study exhibited leucocytosis and augmentation of T& B lymphocytes by 25% approximately. 4–5% increase in Hemoglobin value was also noticed.ConclusionAqueous Ocimum sanctum leaves extract may have stimulatory effect on T & B lymphocytes particularly on Th1 subset of lymphocytes as shown by enhancement in IL-2 production.     

In vitro antimicrobial activity of flavanoids of Ocimum sanctum with synergistic effect of their combined form

ObjectiveTo evaluate the antibacterial activity of flavanoids, Orientin and Vicenin, obtained from leaves of Ocimum sanctum, have also been compared by their combine sample.MethodsAqueous extract of fresh leaves of Ocimum sanctum was assessed for the isolation and purification of different flavanoids. The antibacterial activity of Orientin, Vicenin and Combine sample of both these flavanoids was evaluated according to well diffusion method against some bacteria causing Urinary Tract Infection (UTI) in human.ResultsThe result indicated that the combined sample or synergistic activity of both individual flavanoids showed positive result against Escherichia coli, Proteus, Staphylococcus aureus, Staphylococcus cohni and Klebsialla pneumonia with zone of inhibition 20.12, 20.75, 20.95, 19.55 and 20.1 mm at concentration of 400 mg/ml respectively. But the individual flavanoids showed the positive result against only limited microorganism.ConclusionsThe finding of the present study provides the evidence that this flavanoid sample is used as an antibacterial agent. This is also beneficial to use this combine sample of different flavanoids of Ocimum sanctum for medication and other purposes.     

Effect of Ocimum sanctum on the development of protective immunity against Salmonella typhimurium infection through cytokines

ObjectiveTo investigate the protective role of Ocimum sanctum (O. sanctum) leaves against Salmonella typhimurium(S. typhimurium) infection in rats by inducing TNF-α, IFN-γ& IL-2 cytokines.MethodsWistar albino rats were fed with aqueous extract of O. sanctum leaves using 250 mg/kg body weight dose once a day for 20 consecutive days. Control rats were fed with placebo. Rats were infected with LD 50 dose of S. typhimurium infection and monitored for their survival. Bacterial blood burden in both the groups was compared and numbers of activated peritoneal macrophages were counted. Concentration of TNF-α, IFN-γ and IL-2 cytokines in serum during different time intervals was assayed by sandwich ELISA.ResultsRats of control group showed a high mortality rate and had higher bacterial blood burden when compared with O. sanctum extract fed rats. There was a significant increase in the number of S. typhimurium engulfed peritoneal macrophages in the peritoneal fluid of O. sanctum fed animals. The protective control against bacterial infection in O. sanctum fed rats was associated with elevated level of TNF-α, IFN-γ and IL-2 cytokines in serum.ConclusionsThese findings suggest that orally administered O. sanctum leaves extract effectively enhanced activation in macrophage and lymphocytes, depicted by the elevated serum concentration of TNF-α, IFN-γ and IL-2 cytokines, leading to induce a protective resistance against Salmonella typhimurium infection.     

Plasmid mediated antibiotic resistance of Vibrio cholerae O1 biotype El Tor serotype Ogawa associated with an outbreak in Kolkata,India

ObjectiveTo determine the antibiotic resistance of Vibrio cholerae (V. cholerae) O1 biotype El Tor serotype Ogawa isolates involved in an outbreak of watery diarrhea in Kolkata, and to explore the role of plasmid in mediating antibiotic resistance.MethodsAntibiotic susceptibility and minimum inhibitory concentration (MIC) values of antibiotics for the isolated V. cholerae O1 Ogawa (n=12) were determined by disk diffusion and agar dilution methods, respectively, using ampicillin (Am), chloramphenicol (C), trimethoprim (Tm), tetracycline (T), erythromycine (Er), nalidixic acid (Nx), ciprofloxacin (Cp), amikacin (Ak) and cefotaxime (Cf). Plasmid curing of multidrug resistant (MDR) V. cholerae O1 Ogawa strains was done following ethidium bromide treatment. Following electrophoresis, the plasmid DNAs, extracted from the isolated MDR V. cholerae O1 Ogawa strains and their cured derivatives, were visualized and documented in ‘gel doc’ system.ResultsThe outbreak causing V. cholerae O1 Ogawa isolates were MDR as determined by disk diffusion susceptibility test, and MIC determination. The isolates showed three different drug resistance patterns: AmTmTErNx (for 6 isolates), TmTErCp (for 5 isolates), and AmTmNx (for one isolate), and showed uniform sensitivity to C, Ak and Cf. The loss of plasmids with the concomitant loss of resistance to Am, Tm, T and Er of the isolates occurred following ethidium bromide treatment.ConclusionsThe current findings suggest that the V. cholerae O1 Ogawa associated with the cholera outbreak were MDR, and resistance to Am, Tm, T and Er among the isolates were plasmid mediated.     

Salmonella enterica serovar Typhi plasmid pRST98 enhances intracellular bacterial growth and S. typhi-induced macrophage cell death by suppressing autophagy

ObjectivesPlasmid pR_ST98 is a hybrid resistance-virulence plasmid isolated from Salmonella enterica serovar Typhi (S. typhi). Previous studies demonstrated that pR_ST98 could enhance the virulence of its host bacteria. However, the mechanism of pR_ST98-increased bacterial virulence is still not fully elucidated. This study was designed to gain further insight into the roles of pR_ST98 in host responses.MethodsHuman-derived macrophage-like cell line THP-1 was infected with wild-type (ST8), pR_ST98-deletion (ST8-ΔpR_ST98), and complemented (ST8-c-pR_ST98) S. typhi strains. Macrophage autophagy was performed by extracting the membrane-unbound LC3-I protein from cells, followed by flow cytometric detection of the membrane-associated fraction of LC3-II. Intracellular bacterial growth was determined by colony-forming units (cfu) assay. Macrophage cell death was measured by flow cytometry after propidium iodide (PI) staining. Autophagy activator rapamycin (RAPA) was added to the medium 2 h before infection to investigate the effect of autophagy on intracellular bacterial growth and macrophage cell death after S. typhi infection.ResultsPlasmid pR_ST98 suppressed autophagy in infected macrophages and enhanced intracellular bacterial growth and S. typhi-induced macrophage cell death. Pretreatment with RAPA effectively restricted intracellular bacterial growth of ST8 and ST8-c-pR_ST98, and alleviated ST8 and ST8-c-pR_ST98-induced macrophage cell death, but had no significant effect on ST8-ΔpR_ST98.ConclusionsPlasmid pR_ST98 enhances intracellular bacterial growth and S. typhi-induced macrophage cell death by suppressing autophagy.     

Evaluation of antimicrobial study in in vitro application of Clerodendrum infortunatum Linn.

ObjectiveTo evaluate the antimicrobial potency of ethanol and chloroform extracts of root, leaf and stem of Clerodendrum infortunatum (Verbenaceae) and to explore a scientific data as this plant was randomly use in traditional medicine to cure common ailments such as intestinal disorder, diarrhea, tuberculosis and respiratory problems, etc.MethodsThe in vitro application was carried out by using disc diffusion, micro broth dilution and serial dilution techniques against clinically important life threatening organisms.ResultsAll the extracts showed significant inhibitory activity over the bacteria and fungus comparable to the standard drug tetracycline and fluconazole. The maximum average diameter zone of inhibition was recorded to bacterial strains against Bacillus megaterium, Salmonella typhi, Klebsiella pneumoniae and to fungi against Aspergillus niger and Candida albicans. The minimum inhibitory concentration values of ethanol leaf extract were determined 64 μg/mL to Bacillus megaterium, Salmonella typhi and Klebsiella pneumoniae; 128 μg/mL to Staphylococcus aureus, Streptococcus-β–haemolyticus and Escherichia coli.ConclusionsThe findings evidently appear promising antibacterial and antifungal properties of Clerodendrum infortunatum against antagonistic pathogens. Leaf possesses quite potent activity than root and stem specially leaf extract>root extract>stem extract. This study serves as basis for further research to lead compounds to be isolated so that it may be as a template for the implications of these results for bioactivity and drug discovery potential of herbal products.     

Evaluation of larvicidal activity of medicinal plant extracts against three mosquito vectors

ObjectiveTo evaluate the mosquito larvicidal activity of plant extracts.MethodsThe hexane, chloroform, ethyl acetate, acetone, and methanol leaf, flower and seed extracts of Abrus precatorius (A. precatorius), Croton bonplandianum (C. bonplandianum), Cynodon dactylon (C. dactylon), Musa paradisiaca (M. paradisiaca) and Syzygium aromaticum (S. aromaticum) were tested against fourth instar larvae of Anopheles vagus (An. vagus), Armigeres subalbatus (Ar. subalbatus) and Culex vishnui (Cx. vishnui).ResultsThe highest larval mortality was found in seed ethyl acetate extracts of A. precatorius and leaf extracts of C. bonplandianum, flower chloroform and methanol extracts of M. paradisiaca, and flower bud hexane extract of S. aromaticum against An. vagus with LC₅₀ values of 19.31, 39.96, 35.18, 79.90 and 85.90 μg/mL; leaf ethyl acetate and methanol extracts of C. dactylon, flower methanol extract of M. paradisiaca, flower bud methanol extract of S. aromaticum against Ar. subalbatus with LC₅₀ values of 21.67, 32.62, 48.90 and 78.28 μg/mL, and seed methanol of A. precatorius, flower methanol extract of M. paradisiaca, flower bud hexane extract of S. aromaticum against Cx. vishnui with LC₅₀ values of 136.84, 103.36 and 149.56 μg/mL, respectively.ConclusionsThese results suggest that the effective plant crude extracts have the potential to be used as an ideal ecofriendly approach for the control of disease vectors. This study provides the first report on the larvicidal activity of crude solvent extracts of different mosquitoes.     

The effect of leaves extracts of Clitoria ternatea Linn against the fish pathogens

ObjectiveTo investigate the antimicrobial activity of Clitoria ternatea(C. ternatea) against the fish pathogens viz., Pseudomonas aeruginosa(P. aeruginosa), Escherichia coli(E. coli), Klebsiella pneumonia(K. pneumonia), Bacillus subtilis(B. subtilis), Aeromonas formican(A. formicans)s, Aeromonas hydrophila(A. hydrophila) and Streptococcus agalactiae(S. agalactiae) isolated from diseased Tilapia (Oreochromis niloticus).MethodsThe extracts of C. ternatea was tested against P. aeruginosa, E. coli, K. pneumonia, B. subtilis, A. formicans, A. hydrophila and S. agalactiae by the agar well diffusion method.ResultsDifferent extracts of C. ternatea showed inhibitory effects against P. aeruginosa, E. coli, K. pneumonia, B. subtilis, A. formicans, A. hydrophila and S. agalactiae. Ethyl acetate extracts of C. ternatea showed maximum of zone of inhibition against A. formicans (18 mm), A. hydrophilia (19 mm), B. subtilis (19 mm) and P. aeruginosa (21 mm) next to that ethanol extract of C. ternatea showed A. formicans (18 mm) and E. coli (14 mm) followed by Acetone extract showed maximum zone of inhibition S. agalactiae (19 mm) and K. pneumonia (17 mm).ConclusionsThe antimicrobial activities of all the four plant extracts are comparable and their potential as alternative in the treatment of infectious by these microorganisms was present in the fish. Susceptibility testing is conducted on isolates using drugs selected on the basis of their importance to human medicine and use in fish production.     

Imported Enteric Fever: Case Series from the Hospital for Tropical Diseases,London, United Kingdom

Our current knowledge of the clinical characteristics of enteric fever is drawn mainly from population-based studies in disease-endemic countries, and there are limited data published on cases in returning travelers. We report the clinical characteristics of enteric fever in 92 travelers returning to London, United Kingdom. Salmonella typhi and S. paratyphi resulted in an almost indistinguishable clinical picture. Rose spots and relative bradycardia were found only in a few patients. A total of 91% of the patients had a normal leukocyte count, which was associated with a markedly increased level of alanine aminotransferase in 82%. A total of 57% of the S. typhi isolates had decreased susceptibility to ciprofloxacin and resistance to nalidixic acid; these isolates were from southern Asia. Thirty percent were multidrug resistant; all were from southern Asia and Nigeria. None of the paratyphoid isolates were multidrug resistant but rates of decreased susceptibility to fluoroquinolones were higher than in S. typhi (74%).     

In vitro antiplasmodial activity of marine sponge Clathria vulpina extract against chloroquine sensitive Plasmodium falciparum

ObjectiveTo explore the antiplasmodial potential of marine sponge Clathria vulpina (C. vulpina) against chloroquine sensitive Plasmodium falciparum (P. falciparum).MethodsThe marine sponge C. vulpina was collected from Thondi coast, authenticated and subjected for extraction by soaking in ethanol:water mixture (3:1 ratio). The percentage of extract was calculated. Filter sterilized extracts (100, 50, 25, 12.5, 6.25, 3.125 μg/mL) were screened for antiplasmodial activity against chloroquine sensitive P. falciparum. The extract was also tested for its hemolytic activity.ResultsThe percentage yield of extract of C. vulpina was found to be 4.8%. The crude extract of C. vulpina showed excellent antiplasmodial activity (IC₅₀=14.75 μg/mL) which was highly comparable to the positive control chloroquine (IC₅₀=7 μg/mL). Statistical analysis reveals that the significant antiplasmodial activity (P<0.05) was observed between the concentrations and the time of exposure. The chemical injury to erythrocytes was also carried out, which showed that there were no morphological changes in erythrocytes by the ethanolic extracts of sponges after 48 h of incubation. The extract showed slight hemolytic activity which almost equal to chloroquine at 100 μg/mL concentration (1.023%).ConclusionsThe marine sponge C. vulpina can be used as a putative antiplasmodial drug after completing successful clinical trials.