Antibacterial activity of various leaf extracts of Merremia emarginata

Objective

To investigate the antibacterial activity and phytochemical screening of the aqueous, methanol and petroleum ether leaf extracts of Merremia emarginata (M. emarginata).

Methods

The antibacterial activity of leaf extracts of M. emarginata were evaluated by agar well diffusion method against four selected bacterial species.

Results

The presence of tannins, flavonoids, amino acids, starch, glycosides and carbohydrates in the different leaf extracts was established. The methanol extract was more effective against Bacillus cereus and Escherichia coli, whereas aqueous extract was more effective against Staphylococcus aureus and Pseudomonas aeruginosa.

Conclusions

: The results in the present study suggest that M. emarginata leaf can be used in treating diseases caused by the tested organisms.     

Screening of biological activities of Polygonum maritimum L. from Algerian coast

Objective

To investigate the antioxidant and the antibacterial activities of crude extract from aerial part of Polygonum maritimum L. (Polygonaceae) (P. maritimum) and to find new actives biomolecules.

Methods

The whole plant was collected from the Rechgoune coast (West of Algeria), and methanolic crude extract of aerial parts of P. maritimum (PMCE) was prepared. The extract was tested against different bacterial strain and tested for his ability to neutralize free radical (DPPH) and to scavenge the H₂O₂.

Results

PMCE had a very high content of total phenol, which was (352.49±18.03) mg/g dry weight, expressed as gallic acid equivalent. PMCE exhibited excellent antioxidant activity, as measured using DPPH and H₂O₂ scavenging assays. It also showed a high antibacterial activity against gram-positive bacterial strains: Bacillus cereus, Bacillus subtilis and Staphylococcus aureus with an highest MIC of 120 µg/mL.

Conclusions

The antioxidant and antibacterial activity of the PMCE is probably due to phenolic compounds present in the extract. The contemporary presence of antioxidant and antibacterial activities in the PMCE suggests that this plant may be a source of bioactive substances with multifaceted activity.     

Pharmacognostical,phytochemical and pharmacological evaluation for the antipyretic effect of the seeds of Saraca asoca Roxb.

Objective

To conduct a systemic evaluation of the medicinal value of seeds which include macroscopic and microscopic characterization, physiochemical evaluation, preliminary phytochemical screening and experimental antipyretic activity.

Methods

Saraca asoca seed was studied for pharmacognostical, phytochemical and other recommended methods for standardizations. Also, the acetone extract of the seeds was evaluated for acute toxicity study and antipyretic activity using Brewer''s yeast induced pyrexia in Wistar rats at oral doses of 300 mg/kg and 500 mg/kg.

Results

After phytochemical screening, the acetone extract showed the presence of saponin, tannins and flavonoids which inhibit pyrexia. The therapeutic efficacy achieved at both the dose levels of the research drug and standard drug aspirin (100 mg/kg) showed significant (P<0.01) antipyretic activity when compared to the control group. The highly significant antipyretic effect exhibited at the dose of 500 mg/kg was also found to be sustainable in nature.

Conclusions

The antipyretic effect of the acetone extract showed significant results in rats at the dose of 500 mg/kg after following the standard pharmacognostical and phytochemical methods.     

Evaluation of in-vitro antibacterial activity and anti-inflammatory activity for different extracts of Rauvolfia tetraphylla L. root bark

Objective

To assess the in-vitro antibacterial activity and anti-inflammatory activity of orally administered different extracts (Hydro-alcoholic, methanolic, ethyl acetate and hexane) of Rauvolfia tetraphylla (R. tetraphylla) root bark in Carrageenan induced acute inflammation in rats.

Methods

In-vitro antibacterial activity was evaluated for extracts against four Gram positive and four Gram negative bacteria by using cylinder plate assay. Hydro-alcoholic extract (70% v/v ethanol) at 200, 400 and 800 mg/kg doses and methanolic, ethyl acetate and hexane extracts at doses 100, 200 and 400 mg/kg were tested for anti-inflammatory activity in Carrageenan induced rat paw oedema model and paw thickness was measured every one hour up to 6 hrs.

Results

All extracts of R. tetraphylla root bark showed good zone of inhibition against tested bacterial strains. In Carrageenan induced inflammation model, hydro-alcoholic and methanolic extract of R. tetraphylla root bark at three different doses produced significant (P<0.001) reduction when compared to vehicle treated control group and hexane, ethyl acetate extracts.

Conclusions

In the present study extracts of R. tetraphylla root bark shows good in-vitro antibacterial activity and in-vivo anti-inflammatory activity in rats.     

Antinociceptive activity of Ricinus communis L. leaves

Objective

To evaluate the antinociceptive activity of the methanol extract of Ricinus communis leaves (MRCL).

Methods

Antinociceptive activity was evaluated using acetic acid induced writhing test, formalin induced paw licking and tail immersion method in mice at doses of 100, 125 and 150 mg/kg bw.

Results

The results indicated that MRCL exhibited considerable antinociceptive activity against three classical models of pain in mice. Preliminary phytochemical analysis suggested the presence of saponin, steroids and alkaloids.

Conclusions

It can be concluded that MRCL possesses antinociceptive potential that may be due to saponin, steroids and alkaloids in it.     

Pharmacological screening of methanolic extract of Ixora species

Objective

To investigate the antimicrobial activity of methanolic extracts of different parts of Ixora species.

Methods

Antimicrobial activity was carried out using disc diffusion assay against fungi, gram-positive and gram-negative bacteria.

Results

All methanolic extracts of different parts of Ixora species showed a broad-spectrum of antibacterial and antiyeast activities, which inhibited the growth of at least one bacterium or yeast. There was no remarkable difference between different Ixora species observed in this study.

Conclusions

The significant antimicrobial activity shown by this Ixora species suggests its potential against infections caused by pathogens. The extract may be developed as an antimicrobial agent.     

Antibacterial activity of leaves extracts of Trifolium alexandrinum Linn. against pathogenic bacteria causing tropical diseases

Objective

To investigate antibacterial potential of Trifolium alexandrinum (T. alexandrinum) Linn. against seven gram positive and eleven gram negative hospital isolated human pathogenic bacterial strains responsible for many tropical diseases.

Methods

Non-polar and polar extracts of the leaves of T. alexandrinum i.e., hexane, dichloromethane (DCM), ethyl acetate (EtOAc), methanol (MeOH) and aqueous (AQ) extracts at five different concentrations (1, 2, 5, 10 and 15 mg/mL) were prepared to evaluate their antibacterial value. NCCL standards were strictly followed to perform antimicrobial disc susceptibility test using disc diffusion method.

Results

Polar extracts demonstrated significant antibacterial activity against tested pathogens. EtOAc and MeOH extracts showed maximum antibacterial activity with higher inhibition zone and were found effective against seventeen of the tested pathogens. While AQ plant extract inhibited the growth of sixteen of the test strains. EtOAc and MeOH plant extracts inhibited the growth of all seven gram positive and ten of the gram negative bacterial strains.

Conclusions

The present study strongly confirms the effectiveness of crude leaves extracts against tested human pathogenic bacterial strains causing several tropical diseases. Since Egyptian clover is used as a fodder plant, it could be helpful in controlling various infectious diseases associated with cattle as well.     

Antibacterial and antioxidant activities of Musa sp. leaf extracts against multidrug resistant clinical pathogens causing nosocomial infection

Objective

To investigate different Musa sp. leave extracts of hexane, ethyl acetate and methanol were evaluated for antibacterial activity against multi-drug resistant pathogens causing nosocomial infection by agar well diffusion method and also antioxidant activities.

Methods

The four different Musa species leaves were extracted with hexane, ethyl acetate and methanol. Antibacterial susceptibility test, minimum inhibitory concentration and minimum inhibitory bacterial concentration were determined by agar well diffusion method. Total phenolic content and in vitro antioxidant activity was determined.

Results

All the Musa sp. extracts showed moderate antibacterial activities expect Musa paradisiaca with the inhibition zone ranging from 8.0 to 18.6 mm. Among four species ethyl acetate extracts of Musa paradisiaca showed highest activity against tested pathogens particularly E. coli, P. aeruginosa and Citrobacter sp. The minimum inhibitory concentrations were within the value of 15.63- 250 µg/mL and minimum bactericidal concentrations were ranging from 31.25- 250 µg/mL. Antioxidant activity of Musa acuminate exhibited maximum activity among other three Musa species.

Conclusions

The present study concluded that among the different Musa species, Musa paradisiaca displayed efficient antibacterial activity followed by Musa acuminata against multi-drug resistant nosocomial infection causing pathogens. Further, an extensive study is needed to identify the bioactive compounds, mode of action and toxic effect in vivo of Musa sp.     

Antibacterial activity of sequentially extracted organic solvent extracts of fruits,flowers and leaves of Lawsonia inermis L. from Jaffna

Objective

To reveal the antibacterial activity of sequentially extracted different cold organic solvent extracts of fruits, flowers and leaves of Lawsonia inermis (L. against) some pathogenic bacteria.

Methods

Powders of fruits, flowers and leaves of L. inermis were continuously extracted with dichloromethane (DCM), ethyl acetate and ethanol at ambient temperature. The dried extracts were prepared into different concentrations and tested for antibacterial activity by agar well diffusion method, and also the extracts were tested to determine the available phytochemicals.

Results

Except DCM extract of flower all other test extracts revealed inhibitory effect on all tested bacteria and their inhibitory effect differed significantly (P<0.05). The highest inhibitory effect was showed by ethyl acetate extract of flower against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa), and ethyl acetate extract of fruit on Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis). The ethyl acetate and ethanol extracts of flower, fruit and leaf expressed inhibition even at 1 mg/100 µl against all test bacteria. Among the tested phytochemicals flavonoids were detected in all test extracts except DCM extract of flower.

Conclusions

The study demonstrated that the ethyl acetate and ethanol extracts of fruit and flower of L. inermis are potentially better source of antibacterial agents compared to leaf extracts of respective solvents.     

Antibacterial efficacy of the seed extracts of Melia azedarach against some hospital isolated human pathogenic bacterial strains

Objective

To investigate the antibacterial potential of the polar and non-polar extracts of the seeds of Melia azedarach (M. azedarach) L. (Meliaceae) against eighteen hospital isolated human pathogenic bacterial strains.

Methods

Petrol, benzene, ethyl acetate, methanol, and aqueous extracts at five different concentrations (1, 2, 5, 10 and 15 mg/mL) were evaluated. Disk diffusion method was followed to evaluate the antibacterial efficacy.

Results

All extracts of the seeds demonstrated significant antibacterial activity against tested pathogens. Among all extracts, ethyl acetate extract revealed the highest inhibition comparatively. The present study also favored the traditional uses reported earlier.

Conclusions

Results of this study strongly confirm that the seed extracts of M. azedarach could be effective antibiotics, both in controlling gram-positive and gram-negative human pathogenic infections.     

Antibacterial effect of Allium sativum cloves and Zingiber officinale rhizomes against multiple-drug resistant clinical pathogens

Objective

To evaluate the antibacterial properties of Allium sativum (garlic) cloves and Zingiber officinale (ginger) rhizomes against multi-drug resistant clinical pathogens causing nosocomial infection.

Methods

The cloves of garlic and rhizomes of ginger were extracted with 95% (v/v) ethanol. The ethanolic extracts were subjected to antibacterial sensitivity test against clinical pathogens.

Results

Anti-bacterial potentials of the extracts of two crude garlic cloves and ginger rhizomes were tested against five gram negative and two gram positive multi-drug resistant bacteria isolates. All the bacterial isolates were susceptible to crude extracts of both plants extracts. Except Enterobacter sp. and Klebsiella sp., all other isolates were susceptible when subjected to ethanolic extracts of garlic and ginger. The highest inhibition zone was observed with garlic (19.45 mm) against Pseudomonas aeruginosa (P. aeruginosa). The minimal inhibitory concentration was as low as 67.00 µg/mL against P. aeruginosa.

Conclusions

Natural spices of garlic and ginger possess effective anti-bacterial activity against multi-drug clinical pathogens and can be used for prevention of drug resistant microbial diseases and further evaluation is necessary.     

Antibacterial activity of Lawsonia inermis Linn (Henna) against Pseudomonas aeruginosa

Objective

To investigate the antibacterial activity of henna (Lawsonia inermis Linn) obtained from different regions of Oman against a wide array of micro-organisms.

Methods

Fresh henna samples were obtained from different regions of Oman as leaves and seeds. 100 g fresh and dry leaves and 50 g of fresh and dry seeds were separately soaked in 500 mL of ethanol for three days, respectively, with frequent agitation. The mixture was filtered, and the crude extract was collected. The crude extract was then heated, at 48 °C in a water bath to evaporate its liquid content. The dry crude henna extract was then tested for its antibacterial activity using well-diffusion antibiotic susceptibility technique. Henna extracts were investigated for their antibacterial activity at different concentrations against a wide array of different micro-organisms including a laboratory standard bacterial strain of Pseudomonas aeruginosa (NCTC 10662) (P. aeruginosa) and eleven fresh clinical isolates of P. aeruginosa obtained from patients attending the Sultan Qaboos University Hospital (SQUH). 2-Hydroxy-p-Nathoqinone-Tech (2-HPNT, MW=174.16, C₁₀H₆O₃) was included as control (at 50% concentration) along with the henna samples tested.

Results

Henna samples demonstrated antibacterial activity against all isolates but the highest susceptibility was against P. aeruginosa with henna samples obtained from Al-sharqyia region.

Conclusions

Omani henna from Al-sharqyia region demonstrates high in vitro anti-P. aeruginosa activity compared with many henna samples from different regions of Oman.     

Antioxidant and antibacterial activity of different parts of Leucas aspera

Objective

To evaluate antioxidant, antimicrobial and cytotoxic activity of different parts (root, flower, leaf and stem) of Leucas aspera (L. aspera) (Labiatae).

Methods

Different parts of L. aspera were extracted with 80% (v/v) methanol. The methanol extracts were subjected to antioxidant, antimicrobial and brine shrimp lethality assay.

Results

All the extracts showed moderate to potent antioxidant activity, among which the root extract demonstrated the strongest antioxidant activity with the IC₅₀ value of 6.552 µg/mL. Methanol extract of root possessed antioxidant activity near the range of vitamin E and thus could be a potential rich source of natural antioxidant. In case of antimicrobial screening, crude extracts of root, flower, leaf and stem showed notable antibacterial activity against tested microorganisms. The root extract showed the highest mean zone of inhibition ranging from 9.0–11.0 mm against tested microorganisms, at a concentration of 100 mg/mL. In the brine shrimp lethality bioassay, it was evident that the methanol root extract did not show significant toxicity. The LC₅₀ value for 12 h and 24 h observation was 2.890 mg/mL and 1.417 mg/mL, respectively.

Conclusions

The present finding suggests that the methanol root extract of L. aspera could be developed as pharmaceutical products.     

In vitro biological screening of the stem of Desmodium elegans

Objective

To explore the medicinal importance of the stem of Desmodium elegans, methanolic extract, and its different solvent fractions were evaluated for brine shrimp lethality, insecticidal and phytotoxicity, antifungal, and antibacterial activities.

Methods

The methanolic extract and its solvent fractions were tested for cytotoxic, phytotoxic, insecticidal, antifungal, and antibacterial effects using our previous published protocols.

Results

The methanolic, DCM, ethyl acetate and n-butanol fractions exhibited insecticidal effect against Callosobruchus analis and Rhyzopertha dominic. The methanolic extract, n-hexane, DCM ethyl acetate and n-butanol showed 75, 85, 85, 65 and 5% phytotoxicity at the tested concentration of 500 µg/mL respectively. The solvent fractions (DCM and ethyl acetate) were effective against F. solani (10% and 20% inhibition respectively). All the tested samples were devoid of cytotoxic and antibacterial effects.

Conclusion

It was concluded that this plant can be practiced for control of weeds and insects.     

Production of chitosan from endolichenic fungi isolated from mangrove environment and its antagonistic activity

Objective

To screen the chitosan producing ability of endolichenic fungi and its antibacterial activity.

Methods

Lichen collected from mangroves was screened for endophytes and the chitosan producing ability of endolichenic fungi by submerged fermentation was also determined. Antibacterial activity was carried out against different pathogens.

Results

Totally 4 different groups of fungi were isolated from the lichen Roccella montagnei. Among the four genera, Aspergillus niger (A. niger) is potential to produce chitosan (1.3 g/L) on the twelfth day of incubation. Glucose plays an important role in the productivity of chitosan and the yield was maximum at 10% (1.93 g/L). Antibacterial activity revealed that Vibrio cholerae was sensitive to chitosan followed by Escherichia coli.

Conclusions

In conclusion, our findings suggest that A. niger is a potential candidate to produce more chitosan than the other strains and glucose plays an important role in the production of chitosan which proves to have a good antibacterial activity.     

Antimicrobial activities of the rhizome extract of Zingiber zerumbet Linn

Objective

To investigate antimicrobial effects of ethanolic extract of Zingiber zerumbet (Z. zerumbet) (L.) Smith and its chloroform and petroleum ether soluble fractions against pathogenic bacteria and fungi.

Methods

The fresh rhizomes of Zingiber zerumbet were extracted in cold with ethanol (4.0 L) after concentration. The crude ethanol extract was fractionated by petroleum ether and chloroform to form a suspension of ethanol extract (15.0 g), petroleum ether fraction (6.6 g) and chloroform soluble fraction (5.0 g). The crude ethanol extract and its petroleum ether and chloroform fractions were evaluated for antibacterial and antifungal activity against thirteen pathogenic bacteria and three fungi by the disc diffusion method. Commercially available kanamycin (30 µg/disc) was used as standard disc and blank discs impregnated with the respective solvents were used as negative control.

Results

At a concentration of 400 µg/disc, all the samples showed mild to moderate antibacterial and antifungal activity and produced the zone of inhibition ranging from 6 mm to 10 mm. Among the tested samples, the crude ethanol extract showed the highest activity against Vibrio parahemolyticus (V. parahemolyticus). The minimum inhibitory concentration (MIC) of the crude ethanol extract and its fractions were within the value of 128-256 µg/mL against two Gram positive and four Gram negative bacteria and all the samples showed the lowest MIC value against V. parahemolyticus (128 µg/mL).

Conclusions

It can be concluded that, potent antibacterial and antifungal phytochemicals are present in ethanol extract of Z. zerumbet (L).     

In-vitro antimicrobial activity screening of some ethnoveterinary medicinal plants traditionally used against mastitis,wound and gastrointestinal tract complication in Tigray Region,Ethiopia

Objective

To screen the antibacterial activity of nine ethnoveterinary plants traditionally used for the treatment of mastitis, wound and gastrointestinal complications.

Methods

Hydroalcoholic exctracts of medicinal plants namely, Achyranthes aspera (A. aspera) L. (Family Asparagaceae), Ficus caria (F. caria) (Family Moraceae), Malvi parviflora (M. parviflora) (Family Malvaceae), Vernonia species (V. species) (local name Alakit, Family Asteraceae), Solanum hastifolium (S. hastifolium) (Family Solanaceae), Calpurinia aurea (C. aurea) (Ait) Benth (Family Fabaceae), Nicotiana tabacum (N. tabacum) L. (Family Solanaceae), Ziziphus spina-christi (Z. spina-christi) (Family Rhamnaceae), Croton macrostachys (C. macrostachys) (Family Euphorbiaceae), were screened against clinical bacterial isolates of veterinary importance from October 2007 to April 2009. The antibacterial activity was tested using disc diffusion at two concentrations (200 mg/mL and 100 mg/mL) and broth dilution methods using 70% methanol macerated leaf extracts.

Results

With the exception of S. hastifolium all plant extracts exhibited antibacterial activity. Among the medicinal plants tested C. aurea, C. macrostachyus, A. aspera, N. tabacum and vernonia species (Alakit) showed the most promising antimicrobial properties.

Conclusions

It can be concluded that many of the tested plants have antibacterial activity and supports the traditional usage of the plants for mastitis, wound and gastrointestinal complications treatment. Further studies into their toxicity and phytochemistry is advocated.     

In vitro antibacterial activity of Hibiscus rosa-sinensis flower extract against human pathogens

Objective

To access the in vitro antibacterial activity of Hibiscus rosa-sinensis (H. rosa- sinensis) flower extract against human pathogens.

Methods

Antibacterial activity was evaluated by using disc and agar diffusion methods. The protein was run through poly acrylmide gel electrophoresis to view their protein profile.

Results

The results showed that the cold extraction illustrates a maximum zone of inhibition against Bacillus subtillis (B. subtillis), Escherichia coli (E. coli) viz., (17.00 ± 2.91), (14.50 ± 1.71) mm, followed by hot extraction against, E. coli, Salmonella sp. as (11.66 ± 3.14), (10.60 ± 3.09) mm. In methanol extraction showed a highest zone of inhibition recorded against B. subtillis, E. coli as (18.86 ± 0.18), (18.00 ± 1.63) mm pursued by ethanol extraction showed utmost zone of inhibition recorded against Salmonella sp. at (20.40 ± 1.54) mm. The crude protein from flower showed a maximum inhibitory zone observed against Salmonella sp., E. coli viz., (16.55 ± 1.16), (14.30 ± 2.86) mm. The flower material can be taken as an alternative source of antibacterial agent against the human pathogens.

Conclusions

The extracts of the H. rosa-sinensis are proved to have potential antibacterial activity, further studies are highly need for the drug development.     

Biocompatibility of folate-modified chitosan nanoparticles

Objective

To evaluate the acute toxicity of carboxymethyl chitosan-2, 2′ ethylenedioxy bis-ethylamine-folate (CMC-EDBE-FA) and as well as possible effect on microbial growth and in vitro cell cyto-toxicity.

Methods

CMC-EDBE-FA was prepared on basis of carboxymethyl chitosan tagged with folic acid by covalently linkage through 2, 2′ ethylenedioxy bis-ethylamine. In vivo acute toxicity, in vitro cyto-toxicity and antimicrobial activity of CMC-EDBE-FA nanoparticle were determined.

Results

Vancomycin exhibited the antibacterial activity against vancomycin sensitive Staphylococcus aureus, but CMC-EDBE-FA nanoparticle did not give any antibacterial activity as evidenced by minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), disc agar diffusion (DAD) and killing kinetic assay. Further, the CMC-EDBE-FA nanoparticle showed no signs of in vivo acute toxicity up to a dose level of 1 000 mg/kg p.o., and as well as in vitro cyto-toxicity up to 250 µg/mL.

Conclusions

These findings suggest that CMC-EDBE-FA nanoparticle is expected to be safe for biomedical applications.     

Phytochemical constituents and antibacterial activity of some green leafy vegetables

Objective

To investigate the antibacterial activity and photochemicals of five green leafy vegetables against a panel of five bacteria strains.

Methods

Disc diffusion method was used to determine the antibacterial activity, while kanamycin was used as a reference antibiotic. The phytochemical screening of the extracts was performed using standard methods.

Results

All methanol extracts were found active against all the test bacterial strains. Overall maximum extracts shows antibacterial activity which range from 6 to 15 mm. Proteins and carbohydrates was found in all the green leaves, whereas alkaloid, steroids, saponins, flavonoids, tannins were found in most of the test samples.

Conclusions

The obtain result suggests that green leafy vegetables have moderate antibacterial activity and contain various pharmacologically active compounds and thus provide the scientific basis for the traditional uses of the studied vegetables in the treatment of bacterial infections.