Studies on the antibacterial activity of Khaya senegalensis [(Desr.) A. Juss)] stem bark extract on Salmonella enterica subsp. enterica serovar Typhi [(ex Kauffmann and Edwards) Le Minor and Popoff]

ObjectiveTo study the phytochemical screening and antibacterial activity of the stem bark extracts of Khaya senegalensis (K. senegalensis) against Salmonella enterica subsp. enterica serovar Typhi.MethodsThe plant components were extracted using methanol, ethanol and water. The phytochemical screening of the stem bark extracts were carried out using a standard method. The antibacterial assay of the stem bark extracts against Salmonella Typhi (S. Typhi) using the agar well diffusion method with different concentrations of 50, 100, 200, 400 and 500 mg/mL and the corresponding concentrations of the control was carried out and the result compared with a standard antibiotic, amoxicillin as the control.ResultsThe results obtained from the phytochemical screening of the three plant bark extracts of K. senegalensis showed 10 plant secondary metabolites including saponins, tannins, reducing sugars, aldehyde, phlobatannins, flavonoids, terpenoids, alkaloids, cardiac glycoside and anthroquinones. The ethanol and aqueous extracts showed antibacterial activities against S. Typhi at concentration of 50 mg/mL with the zone diameter of inhibition (ZDI) of 14 mm and 15 mm respectively. The ethanol and aqueous extracts also showed zone diameter of inhibition of 23 mm and 25 mm respectively at 250 mg/mL and 27 mm each at 500 mg/mL. The ethanol and aqueous stem bark extracts gave the highest ZDI at 500 mg/mL while 100 mg/mL gave the least ZDI for ethanol extract and 50 mg/mL for the aqueous extract. This was followed by 400 mg/mL that gave 24 mm ZDI of the aqueous extract and 27 mm of the ethanol extract. The methanol extract showed intermediate susceptibility evidenced by ZDI of 10 mm at 100 mg/mL concentration. The methanol extract also showed antibacterial activity of 24 mm ZDI against the test organism at a higher concentration of 250 mg/mL and 26 mm at 500 mg/mL concentration. The methanol, ethanol and aqueous extracts displayed antibacterial activities against S. Typhi with a statistical significant difference at (P≤0.05). The extracts compared favourably with the standard antibiotic, the control. The minimum inhibitory concentration of the extracts was 250, 200, 200 and 100 mg/mL for methanol, ethanol, aqueous extracts and amoxicillin (control) respectively. The minimum lethal concentration of the extracts was 250, 250, 400 and 200 mg/mL for methanol, ethanol, aqueous extracts and control respectively.ConclusionsThe antibacterial properties of K. senegalensis stem bark extract can be harnessed for the production of new antibiotics or the enhancement of already existing antibiotics.     

西青果丙酮及水提取物体外抗氧化活性初步研究

目的 探讨西青果丙酮提取物和水提取物在3种评价体系下的体外抗氧化活性.方法 采用福林酚比色法测定西青果丙酮提取物和水提取物的总酚含量;利用清除1,1-二.苯基-2-苦肼基自由基(DPPH·)、2,2-联氮基-双-(3-乙基苯并噻唑啉-6-磺酸)二铵盐自由基(ABTS+·)评价法、还原法测定西青果两种溶剂提取物的抗氧化活性.结果 西青果丙酮提取物和水提取物总酚含量分别为(622.19±1.35)mg/g和(457.43±0.96) mg/g;两种溶剂提取物均表现出良好的抗氧化活性,对DPPH、ABTS自由基清除率的IC50值分别为8.427、19.575 μg/mL和20.273、33.064 μg/mL;对Fe3+均有一定的还原能力,其结果与浓度呈良好的量效关系,丙酮提取物还原效果最为明显.结论 西青果丙酮提取物和水提取物具有较强的抗氧化活性.     

Antioxidant potential of phenolic extracts of Mimusops elengi

Objective

To evaluate the antioxidant potential of the phenolic extracts of Mimusops elengi (M. elengi) L. (Sapotaceae).

Methods

The extract of stem bark and seeds of M. elengi were prepared in methanol and acetone:water (7:3). The acetone: water was further partitioned with ethyl acetate and n-butanol. Antioxidant activity of the extracts and partitioned fractions of M. elengi was evaluated in terms of radical scavenging potential (DPPH), inhibition of lipid peroxidation [ferric thiocyanate (FTC)], and total antioxidant activity (phosphomolybdate method). Total phenolics content were calculated using Folin-Ciocalteu reagent.

Results

The stem bark extract partitioned with ethyl acetate exhibited highest amount of total phenols (98.0 mg GAE/g dry weight), among all other extracts, with 92.0% DPPH radical scavenging activity at concentration of 0.5 mg/mL, while methanol extract (stem bark) had maximum inhibition of lipid peroxidation (62.0%) and total antioxidant activity (771.0 mg/g GAE/g). A positive correlation occurred between total phenols and radical scavenging activity (R² = 0.922 9) and total antioxidant activity (R² = 0.945 1).

Conclusions

Our study suggested that antioxidant activity of stembark extract of M. elengi is due the presence of phenolic compounds. Furthermore, the bark extract is a valuable source of natural antioxidants.     

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.     

In vitro control of Staphylococcus aureus (NCTC 6571) and Escherichia coli (ATCC 25922) by Ricinus communis L.

Objective

To evaluate antibacterial activity of hot and cold ethanol and methanol leaf extracts of Ricinus communis L (R. communis) against Staphylococcus aureus (S. aureus) (NCTC 6571) and Escherichia coli (E. coli) (ATCC 25922).

Methods

Leaf powder of R. communis L. was extracted with hot (in Soxhlet) and cold ethanol and methanol, separately. The antibacterial activity of the extracts was determined by agar well diffusion and macro broth dilution methods. The extracts were also subjected to phytochemical analysis.

Results

All the four test extracts showed inhibition on both S. aureus and E. coli. Hot and cold ethanol extracts revealed significantly (P<0.05) higher inhibition on S. aureus than methanol extracts, and the hot ethanol extract had the lowest minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values (5 mg/mL and 10 mg/mL, respectively). E. coli was highly inhibited by hot extracts of both ethanol and methanol with the MIC and MBC of 40 mg/mL and 80 mg/mL, respectively. Phytochemical analysis revealed the presence of saponins, cardiac glycosides, tannins, flavonoids and terpenoids in all test extracts.

Conclusions

This study demonstrates that the hot and cold methanol and ethanol extracts are potential sources for control of S. aureus and E. coli. Especially, the hot and cold extracts of ethanol are more inhibitive against S. aureus even at lower concentration. Further study is needed to identify the specific bioactive compounds, their mode of action and their nontoxic nature in vivo condition.     

Bioactivity of seagrass against the dengue fever mosquito Aedes aegypti larvae

Objective

To identify the larvicidal activity of the seagrass extracts.

Methods

Seagrass extracts, Syringodium isoetifolium (S. isoetifolium), Cymodocea serrulata and Halophila beccarii, were dissolved in DMSO to prepare a graded series of concentration. Batches of 25 early 4th instars larvae of Aedes aegypti (Ae. aegypti) were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts (0.01 mg – 0.1 mg). After 24 h the mortality rate was identified with the formulae [(% of test mortality – % of control mortality)/(100 – % of control mortality)] × 100. Each experiment was conducted with three replicates and a concurrent control group. A control group consisted of 1 mL of DMSO and 199 mL of distilled water only.

Results

: The root extract of S. isoetifolium showed maximum larvicidal activity with minimum concentration of extract of LC₅₀= 0.0 604 ± 0.0 040)µg/mL with lower confidence limit (LCL) – upper confidence limit (UCL) = (0.051–0.071) and LC₉₀=0.0 972µg/mL followed by leaf extract of S. isoetifolium showed LC₅₀= (0.062 ± 0.005)µg/mL. The regression equation of root and leaf extract of S. isoetifolium for 4th instar larvae were Y= 4.909 + 1.32x (R²= 0.909) and Y= 2.066 + 1.21x (R² =0.897) respectively. The results of the preliminary phytochemical constituents shows the presence of saponin, steroids, terpenoid, phenols, protein and sugars.

Conclusions

From the present study the ethanolic extracts of seagrass of S. isoetifolium possesses lead compound for development of larvicidal activity.     

Laboratory assessment of the molluscicidal and cercariacidal activities of Balanites aegyptiaca

Objective

To assess the molluscicidal and cercariacidal activities of aqueous extracts of Balanites aegyptiaca (B. aegyptiaca) against Ethiopian Biomphalaria pfeifferi (B. pfeifferi), Lymnaea natalensis (L. natalensis) and Schistosoma mansoni (S. mansoni) cercariae.

Methods

Extracts of seeds, endocarp, mesocarp, and fruit of B. aegyptiaca were tested for their activities against adult B. pfeifferi and L. natalensis. The cercariacidal activity of the seeds of the plant was also evaluated against S. mansoni. Bioassays were carried out following the methods recommended by WHO. Snail mortalities were compared between each plant part and snail species, and LC₅₀ and LC₉₀ values for the plant parts tested were computed. The cercariacidal activity of the plant was assessed by exposing the mice to the cercariae pre-exposed to aqueous extract of B. aegyptiaca seeds.

Results

For the molluscicidal activities of seeds, endocarp, mesocarp and whole fruit, the LC₅₀ values against B. pfeifferi were 56.32, 77.53, 65.51 and 66.63 mg/L, respectively, while the respective LC₉₀ values were 77.70, 120.04, 89.50 and 97.55 mg/L. Similarly, the LC₅₀ values for the seeds, endocarp, mesocarp and whole fruit against L. natalensis were 80.33, 92.61, 83.52 and 87.84 mg/L, respectively, while the respective LC₉₀ values were 102.30, 138.21, 115.42 and 127.69 mg/L. B. pfeifferi were found to be more susceptible to B. aegyptiaca than L. natalensis. S. mansoni cercariae exposed to 15 mg/L of extract of seeds were incapable of infecting mice. The mean egg load of tissue was reduced in mice infected with the cercariae exposed to 5 and 10 mg/L of the extract.

Conclusions

The aqueous extracts of different parts of B. aegyptiaca exhibited reasonable molluscicidal activity against B. pfeifferi and L. natalensis, as well as cercariacidal activity against S. mansoni cercariae. However, comprehensive laboratory evaluation is recommended prior to field tests of the plant parts since their impact on other aquatic biota is not known.     

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.     

Chromatographic finger print analysis of anti-inflammatory active extract fractions of aerial parts of Tribulus terrestris by HPTLC technique

Objective

To develop HPTLC fingerprint profile of anti-inflammatory active extract fractions of Tribulus terrestris (family Zygophyllaceae).

Methods

The anti-inflammatory activity was tested for the methanol and its fractions (chloroform, ethyl acetate, n-butanol and aqueous) and chloroform extract of Tribulus terrestris (aerial parts) by injecting different groups of rats (6 each) with carrageenan in hind paw and measuring the edema volume before and 1, 2 and 3 h after carrageenan injection. Control group received saline i.p. The extracts treatment was injected i.p. in doses of 200 mg/kg 1 h before carrageenan administration. Indomethacin (30 mg/kg) was used as standard. HPTLC studies were carried out using CAMAG HPTLC system equipped with Linomat IV applicator, TLC scanner 3, Reprostar 3, CAMAG ADC 2 and WIN CATS-4 software for the active fractions of chloroform fraction of methanol extract.

Results

The methanol extract showed good antiedematous effect with percentage of inhibition more than 72%, indicating its ability to inhibit the inflammatory mediators. The methanol extract was re-dissolved in 100 mL of distilled water and fractionated with chloroform, ethyl acetate and n-butanol. The four fractions (chloroform, ethyl acetate, n-butanol and aqueous) were subjected to anti-inflammatory activity. Chloroform fraction showed good anti-inflammatory activity at dose of 200 mg/kg. Chloroform fraction was then subjected to normal phase silica gel column chromatography and eluted with petroleum ether-chloroform, chloroform-ethyl acetate mixtures of increasing polarity which produced 15 fractions (F1-F15). Only fractions F1, F2, F4, F5, F7, F9, F11 and F14 were found to be active, hence these were analyzed with HPTLC to develop their finger print profile. These fractions showed different spots with different R_f values.

Conclusions

The different chloroform fractions F1, F2, F4, F5, F7, F9, F11 and F14 revealed 4, 7, 7, 8, 9, 7, 7 and 6 major spots, respectively. The results obtained in this experiment strongly support and validate the traditional uses of this Sudanese medicinal plant.     

Phytochemical screening and free radical scavenging activity of Citrullus colocynthis seeds extracts

Objective

To study the phytochemical screening of different extracts from Citrullus colocynthis (C. colocynthis ) seeds extracts and to assess their antioxidant activity on the DPPH free radical scavenging.

Methods

Phytochemical screening, total content of polyphenols and flavonoids of C. colocynthis seeds extracts, including a crude aqueous extract (E1), a defatted aqueous extract (E2), a hydromethanolic extract (HM), an ethyl acetate extract (EA) and a n-butanol extract (n-B) was carried out according to the standard methods and to assess their corresponding effect on the antioxidant activity of this plant.

Results

None of these extracts contained detectable amount of alkaloid, quinone, antraquinone, or reducing sugar. Catechic tannins and flavonoids were abundant in E1, HM and EA, whilst terpenoids were abundantly present in E1 and n-B but only weekly in HM. Coumarins were found in E2, EA and n-B. Polyphenols, expressed as gallic acid equivalent, amounted, per 100 g plant matter, to 329, 1002 and 150 mg in EA, HM an E1 respectively. Flavonoids, expressed as catechin equivalent, amounted, per 100 g plant matter to 620, 241 and 94 mg in EA, HM and E1 respectively. Comparable values were found in n-B and E1, with lower values in E2. Quercetin, myricetin and gallic acid were found in the EA and HM extracts by thin layer chromatography, The antioxidative effect of these extracts yielded, when tested at a concentration of 2 000 µg/mL in a 1,1-diphenyl-2-picrylhydrazyl assay, a reducing percentage of 88.8% with EA, 74.5% with HM and 66.2% with E1, and corresponding IC₅₀ of 350, 580 and 500 µg/mL as compared to 1.1 µg/mL for ascorbic acid.

Conclusions

These qualitative and quantitative analytical data document the presence in C. colocynthis extracts of such chemical compounds as flavonoids responsible for the antioxidant activity, as well as other biological activities of this plant.     

Anti-dermatophytic activity of marine sponge,Sigmadocia carnosa (Dendy) on clinically isolated fungi

Objective

To screen the anti-fungal effects and find out the active metabolites from sponge, Sigmadocia carnosa (S. carnosa) against four dermatophytic fungi.

Methods

The methanol, ethyl acetate and acetone extract of marine sponge, S. carnosa was examined against Trichophyton mentagrophytes (T. mentagrophytes), Trichophyton rubrum (T. rubrum), Epidermophyton floccosum (E. floccosum) and Microsporum gypseum (M. gypseum) and qualitative analysed to find out the active molecules.

Results

The methanol extract of sponge was expressed significant activity than ethyl acetate and acetone. The minimum inhibitory concentration (MIC) of methanol extract of sponge that resulted in complete growth inhibition of T. mentagrophytes, T. rubrum, E. floccosum and M. gypseum were found to 125, 250, 250 and 250 µg/mL respectively. But, 100 % inhibition of fungal spore germination was observed in T. mentagrophytes at 500 µg/mL concentration followed by T. rubrum, E. floccosum and M. gypseum at 1 000 µg/mL concentration. Other two extracts showed weak anti spore germination activity against the tested dermatophytic fungi. Methanol extracts showed presence of terpenoids, steroids, alkaloids, saponins and glycosides.

Conclusion

Based on the literature, this is the first study which has conducted to inhibit the growth and spore germination of dermatophytic fungi with S. carnosa. Further research also needs to purify and characterize the secondary metabolites from the sponge, S. carnosa for the valuable source of novel substances for future drug discovery.     

Control of human filarial vector,Culex quinquefasciatus Say 1823 (Diptera: Culicidae) through bioactive fraction of Cayratia trifolia leaf

Objective

To investigate the mosquito larvicidal activity of Cayratia trifolia (L.) Domin (Vitaceae: Vitales) (C. trifolia) which is distributed in many parts of India with medicinal properties as vector control is facing threat due to the emergence of resistance to synthetic insecticides.

Methods

Young and mature leaves of C. trifolia were investigated for larvicidal activity against 3rd instars larvae of Culex quinquefasciatus in different seasons throughout the year. The active fractions were extracted using six different solvents in a non-polar to polar fashion viz petroleum-ether, benzene, chloroform: methanol (1:1 v/v), acetone, absolute alcohol and distilled water. Dose dependent mortality was recorded against each solvent extract. Determination of LD₅₀ and LD₉₀ were executed through log-probit analysis using the most bioactive fraction. The fluctuations in mortality were statistically co-related through ANOVA analyses concerning different seasons and types of leaves as random variables. Justification of larvicidal activity was established through student''s t-test. Costing effects were evaluated on the non-target water fauna under laboratory conditions. Thin layer chromatographic techniques were performed for phytochemical analysis and categorization of chemical personality of the active fractions using the most effective solvent extract following standard methods.

Results

Significant variations in mortality rate were noted with respect to the type of leaves (mature and senescence), concentration of leaf extract and between seasons. The water extract among all the solvent extracts was found to induce cent percent mortality at 50 mg/L in test mosquito species within 24 h with a LD₅₀ and LD₉₀ value of 10.70 mg/L and 27.64 mg/L respectively. No significant mortality was recorded in non-target water population. Chromatographic analyses of the water extract revealed the presence of steroids, triterpene glycosides, essential oil, phenolics and diterpenes as secondary phytochemicals.

Conclusions

Water extract of C. trifolia leaf promised as a cost effective and potent larvicidal agent against Culex quinquefasciatus.     

Larvicidal and repellent potential of Moringa oleifera against malarial vector,Anopheles stephensi Liston (Insecta: Diptera: Culicidae)

Objective

To evaluate the larvicidal and pupicidal potential of the methanolic extracts from Moringa oleifera (M. oleifera) plant seeds against malarial vector Anopheles stephensi (A. stephensi) mosquitoes at different concentrations (20, 40, 60, 80 and 100 ppm).

Methods

M. oleifera was collected from the area of around Bharathiar University, Coimbatore. The dried plant materials were powdered by an electrical blender. From each sample, 100 g of the plant material were extracted with 300 mL of methanol for 8 h in a Soxhlet apparatus. The extracts were evaporated to dryness in rotary vacuum evaporator to yield 122 mg and 110 mg of dark greenish material (residue) from Arcang amara and Ocimum basilicum, respectively. One gram of the each plant residue was dissolved separately in 100 mL of acetone (stock solution) from which different concentrations, i.e., 20, 40, 60, 80 and 100 ppm were prepared.

Results

Larvicidal activity of M. oleifera exhibited in the first to fourth instar larvae of the A. stephensi, and the LC₅₀ and LC₉₀ values were 57.79 ppm and 125.93 ppm for the first instar, 63.90 ppm and 133.07 ppm for the second instar, 72.45 ppm and 139.82 ppm for the third instar, 78.93 ppm and 143.20 ppm for the fourth instar, respectively. During the pupal stage the methanolic extract of M. oleifera showed that the LC₅₀ and LC₉₀ values were 67.77 ppm and 141.00 ppm, respectively.

Conclusions

The present study indicates that the phytochemicals derived from M. oleifera seeds extracts are effective mosquito vector control agents and the plant extracts may be used for further integrated pest management programs.     

塞隆骨提取物对体外大鼠成骨样细胞ROS17/2.8的影响

目的研究塞隆骨提取物对体外培养大鼠成骨样细胞ROS17/2.8代谢功能的调节作用,从而在细胞水平上阐述塞隆骨防治骨质疏松的作用机制及药效成分的筛选。方法采用超临界萃取法制备塞隆骨的脂、醇、水提液及水煎提取液,用MTT法测定塞隆骨脂、醇、水提液及水煎液对成骨样细胞的增殖作用;测定碱性磷酸酶(ALP)活性,观察上述提取液对细胞分化的影响。结果10mg/mL塞隆骨脂提液和水提液对大鼠成骨样细胞ROS17/2.8有显著的增殖作用(P<0.01);ALP检测结果显示,10mg/mL脂提液能极显著增强成骨样细胞内ALP活性(P<0.01),1.0、0.1mg/mL能提高ALP活性(P<0.05);10mg/mL水提液能使ALP活性升高(P<0.05)。结论塞隆骨脂和水提取液中分别存在有较高活性的促成骨样细胞增殖、分化的物质,可作为虎骨的替代中药。     

Antimicrobial potential of selected brown seaweeds from Vedalai coastal waters,Gulf of Mannar

Objective

To evaluate the antimicrobial activity of Turbinaria conoides (T. conoides), Padina gymnospora (P. gymnospora) and Sargassum tenerrimum against human bacterial and fungal pathogens.

Methods

The antimicrobial activities of the extracts against various organisms were tested by using disc diffusion method.

Results

The methanol extract showed the better result than the other extracts. Whereas, the strong antibacterial inhibition was noted in methanol extracts of P. gymnospora against Bacillus subtilus (26.33±1.86) and the mild inhibition of ethanol extracts from T. conoides against Klebsiella pneumoniae (2.33±0.51). Acetone extraction of P. gymnospora had strong antifungal inhibition against Cryptococcus neoformans (23.00±1.78), and acetone extract of T. conoides had mild inhibition against Aspergillus niger (3.00±0.89).

Conclusions

The seven different solvent extracts of seaweeds used in the present study have shown significant bacterial action. Further, a detailed study on the principle compound in the seaweeds which is responsible for antimicrobial activity is still needed and it can be achieved by using advanced separation techniques.     

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.     

In vitro analysis on bactericidal screening and antioxidant potentiality of leaf and root extracts of Thottea siliquosa (Lam.) Ding Hou. An ethnobotanical plant

Objective

Natural products of plant origin are potential source of novel antimicrobial and antioxidative agents. Thottea siliquosa (Lam.) Ding Hou. (T. siliquosa). A medicinal herb used by local tribals for treating various ailments. The present study aims at the phytochemical screening, GC-MS analysis, in vitro antibacterial activity and antioxidant potentiality of root and leaf extracts of T. siliquosa.

Methods

Hot continuous Soxhlet extraction, GC-MS analysis, antibacterial analysis by disc diffusion, microdilution assay and antioxidant potentialities by hydroxyl radical and nitric oxide radical scavenging. The data was statistically analyzed.

Results

Phytochemical screening of the ethyl acetate and methanolic extract of leaf and root revealed the presence of phenols, alkaloids, tannins and saponin. The extract revealed a pool of phytochemicals by comparison with authentic standards from spectral library. Both the extracts has shown their broad spectrum of inhibition against the selected bacteria Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia compared with standard antibiotic drug streptomycin. The extracts showed antioxidant activity by scavenging of free radicals such as hydroxyl and nitric oxide. The IC₅₀ values of the ethyl acetate extracts leaf and root and standard in this assay were 167.5±0.67, 99.4±1.2, 192±2.5 µg/mL respectively. Similarly those methanolic extracts of leaf and root were 269.5±0.89 and 289.1±2.66 µg/mL respectively. Similarly, ethyl acetate and methanolic extracts also caused a moderate dose-dependent inhibition of nitric oxide with an IC₅₀ range 65.5±1.55 to 148 ±3.09 µg/mL. The inhibitory activities were found to be dose dependent.

Conclusion

The present study provides evidence that ethyl acetate and methanol extract of leaf and root of T. siliquosa are potential source of natural antioxidants and bactericidal nature. It is essential that research should continue to isolate and purify the bio active components of this natural plant and use in drug discovery and development.     

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 antimicrobial activity and bronchodialator effect of a polyherbal drug-Shrishadi

Objective

To investigate antimicrobial and bronchodialator effect of hydroalcholic extract of polyherbal drug Shirishadi containing Shirisha (Albezzia lebbeck), Nagarmotha (Cyprus rotandus) & Kantakari (Solanum xanthocarpum).

Methods

Antimicrobial activity was evaluated by disc diffusion method and MIC, MBC, MFC were calculated by micro dilution method. Hydroalcholic extract of this preparation was investigated for its phytochemical analysis, phenol and flavonoid were determined by spectrophotometric method and in vivo bronchodilator effect was analysed by convulsion time.

Results

The phytochemical tests revealed presence of alkaloids, anthraquinones, carbohydrates, flavonoids, saponins and tannins. The antimicrobial result showed the MIC of 6.25 mg/mL against Staphylococcus aureus and 12.5 mg/mL for Escherichia coli and 12.5 mg/mL against remaining bacteria tested, with strong antifungal activity. The maximum inhibition zone is found against Pseudomonas aeruginosa with MIC 16 mg/mL. Drug showed significant bronchodilator effect with 27.86% & 36.13% increase in preconvulsion time of guinea pigs pretreated with 100 & 200 mg/kg body weight of extract.

Conclusions

The study reveals that the extracts possess antibacterial activity and antifungal activity in a dose dependent manner. This antimicrobial property may be due to presence of several saponins, further studies are highly needed for the drug development.     

Studies on the anti-diarrheal properties of leaf extract of Desmodium puchellum

Objective

To evaluate the pharmacological activity against diarrhea of methanol and petroleum ether extract of Desmodium puchellum (Family: Fabaceae) leaves.

Methods

The extract was evaluated for castor oil-induced diarrhea and enteropooling as well as intestinal motility in rats. Both of the extracts were given to the rats at 200 mg/kg orally. Loperamide was used as a standard drug for diarrhea.

Results

The diarrheal severity was reduced significantly (P<0.05) by methanol and petroleum ether extracts by 31.95% and 28.33%, respectively, whereas 54.75% inhibition was found for standard drug loperamide at 5 mg/kg. The two extracts also significantly (P<0.05) reduced the intestinal volume in case of castor oil induced enteropooling.

Conclusions

It is concluded that both fractions contain some biologically active ingredients that are active for anti-diarrheal actions whereas methanol fraction has better potential.