Bactericidal, fungicidal and anthelmintic activities of Alstonia scholaris bark extracts (original) (raw)
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Cellular and Molecular Biology, 2020
Alstonia sholaris is an evergreen tree commonly found in South East Asia. In traditional medicine pharmacological activities are attributed to the leaves and bark of this plant. The aim of this study is characterizing the chemicals present in A. sholaris leaves and bark extracts and study their antimicrobial activities. Solvent extractions with Soxhlet apparatus of leaves and bark were obtained using hexane, benzene, isopropanol, methanol, and water. The crude extracts were concentrated and screened for qualitative phytochemical analysis and thin layer chromatography, and the antibacterial, antifungal an antiviral activity of crude extracts were measured by in vitro methods. Isopropanol and methanol extracts showed significant antibacterial activity and it was more pronounced against Gram positive than against Gram negative bacteria. Hexane, benzene, isopropanol and methanol fractions of A. scholaris bark and leaf showed activity against Enterobacter cloacae. Isopropanol extract sho...
Phytochemical and antibacterial properties of leaves of Alstonia scholaris
Phytochemical and antibacterial activity of leaves of Alstonia scholaris R.Br. was investigated. The different solvent extracts showed the presence of Iridoids, alkaloids, coumarins, flavonoids, leucoanthocyanins, reducing sugars, simple phenolics, steroids, saponins and tannins. Antibacterial activity was tested against both Gram +ve and -ve organisms. The methanol leaves extract exhibited broad-spectrum antibacterial activity against tested organisms. Maximum activity was exhibited against Bacillus subtilis followed by Escherichia coli and Staphylococcus aureus. Chloroform and acetone leaf extracts exhibited lesser activity, while petroleum ether extract showed no inhibition.
Advances in Bioscience and Bioengineering, 2019
Background: Prohibitive cost of treatments in developing countries is a challenge under poor economic circumstances. Side effects of several synthetic drugs and the development of resistance to currently used antibiotics for infectious diseases have led to increased emphasis on the use of plant materials as a source of medicine for a wide variety of human ailments. In addition to this and the high level of poverty in developing countries, the use of alternate medicine to cure some diseases is now encouraged in Nigeria to serve as an alternative for orthodox medicine. In this study, phytochemical screening and the anti-microbial capability of parts of a popular African medicinal plant, Alstonia congensis, was evaluated. Materials and Methods: The effects of the plant parts extracts on some human pathogenic bacteria viz; Escherichia coli, Neisseria gonorrhoeae, Staphylococcus aureus, Salmonella typhi, Proteus mirabilis, Pseudomonas aeruginosa and Klebsiella pneumoniae were examined in vitro using hexane, ethanol, petroleum ether and water (aqueous) as extractants and at concentrations of 120, 80, 60, 48 and 40mg/ml respectively. Agar well diffusion technique was employed throughout the experimentation. It was discovered that petroleum ether and ethanolic extracts of the leaves and stem bark showed appreciable inhibitory effects on the test bacteria (the leaf extracts were more potent than the stem bark extracts). The Minimum Inhibitory Concentration (MIC) of each of the extracts was determined. Results: Petroleum ether as well as ethanolic extracts of the leaves was effective on all the bacterial isolates at MIC between 40 mg/ml and 60mg/ml respectively while the aqueous extract of the leaf was slightly effective on E. coli, N. gonorrhoeae, Staphylococcus aureus, S. typhi and P. mirabilis at MIC between 60mg/ml and 80mg/ml. It was only the hexane extract of the leaf that was not effective against any of the test bacteria. The ethanolic and petroleum ether extracts ADVANCES IN BIOSCIENCE AND BIOENGINEERING 22 of the stem bark was effective against Staphlococcus aureus, S. typhi, P. mirabilis and Klebsiella pneumoniae at MIC between 40mg/ml and 60mg/ml while ethanolic extract of the leaf was not effective against E. coli. Likewise, the hexane extract of the stem bark was not effective against Neisseria gonorrhoeae. The aqueous extract of the stem bark showed no effect against Escherichia coli but slightly effective against other isolates at MIC of 80mg/ml for Neisseria gonorrhoeae, Staphylococcus aureus, Salmonella typhi, Proteus mirabilis, Pseudomonas aeruginosa and at120mg/ml for Klebsiella pneumoniae. Hexane extract of the stem bark did not have any effect against Neisseria gonorrhoeae, Staphylococcus aureus, Salmonella typhi and Pseudomonas aeruginosa but very effective against Escherichia coli and Proteus mirabilis at MIC of 60mg/ml but at 40mg/ml for Klebsiella pneumoniae. Petroleum ether and ethanolic extracts showed much wider zones of inhibition on each of the test bacteria and therefore regarded as the best solvents for extraction. The result of the Standard Antibiotics Disc (SAD) showed that E.coli was inhibited by Ofloxacin (21mm), Klebsiella pneumoniae (22mm), P.aeruginosa (24mm), N. gonorrhoeae (25mm), S. typhi and P. mirabilis (30mm). E. coli and N. gonorrhoeae was inhibited by Nalidixic acid (22mm), S. typhi and P. aeruginosa (20mm) and Klebsiella pneumoniae (10mm). Also, Gentamycin inhibited E.coli (9mm), N. gonorrhoeae (13mm), S. typhi (12mm), P. mirabilis (13mm) and P.aeruginosa (15mm) except Staphylococcus aureus which was not inhibited by any of these antibiotics. On the other hand, all the isolates exhibited resistance to Amoxycillin while E. coli, N. gonorrhoeae, S. typhi, Klebsiella pneumoniae, P.mirabilis and P. aeruginosa were resistant to Chloramphenicol, Tetracycline, Cloxacillin, Erythromycin, Augmentin and Streptomycin. Conclusion: The plant's parts were found to possess antibacterial activities. The ethanol and petroleum ether were the best solvents for their extraction.
Antibacterial Activity of Plant Extracts of Alstonia scholaris
The present study aims to investigate the antibacterial activity of leaves of Alstonia scholaris against bacterial pathogens by disc diffusion method, well method and incorporating the extract in the media before solidifying. The result of disc diffusion technique showed that fractions of leaf extract had pronounced antibacterial activity against Methicillin Resistant Staphylococcus aureus (MRSA) and the clinical strain Providence stuartii. Antibacterial activity was also tested against a large group of Gram positive and Gram negative bacteria and it was found to reside maximum in the butanol and ethyl acetate fractions of methanol extract of leaf and bark.
Antimicrobial and Phytochemical Properties of Alstonia BooneiExtracts
Alstonia boonei De wild is a major spice crop grown abundantly in Ghana and other tropical countries. In this study we have carried out phytochemical analysis and antimicrobial investigation of ethanol and aqueous extracts of the root of Alstonia boonei against a panel of clinically signifiant bacterial and fungal strains. Four Gram positive and Gram negative bacteria namely Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus were subjected to test the antimicrobial activity along with one fungi namely, Candida albicans. The ethanol and aqueous extracts of root of Alstonia boonei were subjected to microbial susceptibility assays using agar well diffusion method. Phytochemical screening was done to test the presence of phytochemicals responsible for the antimicrobial potential of roots of Alstonia boonei. The results of the phytochemical studies revealed the presence alkaloids, cyanogenetic glycosides, flvonoids, terpenoids and steroids and saponins....
In vitro anthelmintic activity of stem and root barks of Alstonia boonei De Wild
Journal of Medicinal Plants Research, 2016
Alstonia boonei De Wild ethanol extracts of the stem bark (ABSB) and root bark (ABRB) were evaluated for possible anthelmintic activity. Three different concentrations of each extract (50, 100 and 150 mg/ml) were evaluated for in vitro anthelmintic activity by determining the effects of the extracts on the paralysis and death times of Pheretima posthuma. Mebendazole (MBZ) 15 mg/mg was used as reference anthelmintic. ABSB and ABRB demonstrated a concentration dependent anthelmintic activity with a reduction in paralytic and death times upon increase in the concentration of the extracts. ABSB revealed better anthelmintic activity than ABRB at all concentrations tested. ABSB also revealed a significant paralytic time (p<0.01) at 150 mg/ml with reference to MBZ. Phytochemical screening revealed the presence of alkaloids, tannins, flavonoids saponins and glycosides in ABSB and ABRB.
The fresh barks of A. scholaris R. Br. were collected in the month of October 2005 from forest area of Aurangabad ABSTRACT Comparative phytochemical and antibacterial activities of bark of Alstonia scholaris and Alstonia macrophylla were investigated. The successive different solvent extracts showed the presence of alkaloids, phenolics, saponins and tannins were found in both the species. The antibacterial activities of bark of A. scholaris and A. macrophylla in successive different solvent were tested against gram +ve and gram −ve organisms. The chloroform extracts of A. macrophylla showed broader spectrum of antibacterial activity when compared with A. scholaris. However. Alstonia scholaris is widely used medicinal plant.
Alstonia scholaris: It′s Phytochemistry and pharmacology
Chronicles of Young Scientists, 2011
Complementary therapies based on herbal medicines are the world's oldest form of medicine and recent reports suggest that such therapies still enjoy vast popularity, especially in developing countries where most of the population does not have easy access to modern medicine. Alstonia scholaris (L.) R.Br (Apocynaceae) is an evergreen tropical tree native to Indian sub-continent and South East Asia, having grayish rough bark and milky sap rich in poisonous alkaloid. It is reported to contain various iridoids, alkaloids, coumarins, flavonoids, leucoanthocyanins, reducing sugars, simple phenolics, steroids, saponins and tannins. It has been reported to possess antimicrobial, antiamoebic, antidiarrheal, antiplasmodial, hepatoprotective, immunomodulatory, anticancer, antiasthmatic, free radical scavenging, antioxidant, analgesic, anti-inflammatory, antiulcer, antifertility and wound healing activities. In other parts of the world, it is used as a source cure against bacterial infection, malarial fever, toothache, rheumatism, snakebite, dysentery, bowl disorder, etc. Reports on the pharmacological activities of many isolated constituents from A. scholaris (L.) R.Br are lacking, which warrants further pharmacological studies.
PHYTOCHEMICAL INVESTIGATION AND ANTIBACTERIAL ACTIVITY OF THE FRUITS OF ALSTONIA SCHOLARIS
The present paper is aimed at the phytochemical analysis and antibacterial activity of the fruits of Alstonia scholaris. The findings of the work revealed that the solvent extract of plant showed the presence of phytochemical constituents like alkaloids, carbohydrates, phenolic compounds, terpenoids, cardiac glycosides and flavanoids in major amounts while fixed oils and fats, saponins and steroids in lesser amounts. These phytochemicals have reported to have conferred the necessary bioactivity to the plant like the antibacterial activity. However the test of antibacterial activity showed dose dependent inhibition of bacteria with maximum antibacterial activity in case of benzene and butanol solvent inhibiting Lactobacillus lactis and Staphylococcus aureus respectively. However least antibacterial activity was seen in case of hexane extract and aqueous and methanolic extract showed overall higher activity compared to other extract. The results of antibacterial activity are quite similar to standard antibiotic chloramphenicol thus indicating the possible cure of bacterial pathogenic diseases using these plant extracts in future.