Comparative study of phytochemical screening, antioxidant and antimicrobial capacities of fresh and dry leaves crude plant extracts of Datura metel L

Phytochemical screening and antimicrobial activity of root and stem extracts of wild Eurycoma longifolia Jack (Tongkat Ali)

Enormous marine biodiversity offers an endless reservoir of chemicals for many applications. In this scenario, the extraction of seaweeds represents an interesting source of compounds displaying antimicrobial activity. In particular, among the different red algae, Gracilaria gracilis plays an important role due to the presence of important bioactives in its composition. In spite of these features, an efficient culture system is still absent. In the present study, a novel algal culture method was developed and compared to another more common cultural practice, widely reported in literature. A higher efficiency of the new method, both for daily growth rate and biomass, was assessed. Furthermore, the growth inhibitory activity of five extracts, obtained using ethanol, methanol, acetone, chloroform or diethyl ether as a solvent, from the cultured G. gracilis was tested against Gram-positive and Gram-negative pathogens. Algal extracts exhibited a considerable inhibitory activity against B. subtilis strains, while a slight inhibition was observed against V. fischeri. The different extracts showed significant differences in bacterial growth inhibition, with the highest activity that was recorded for the ethanol extract, followed by that of methanol. Based on the chemical characterization, these findings could be related to the antimicrobial activity played by the combination of total carbohydrates and polyphenols, which were determined at high levels in ethanol and methanol extracts, as well as by the highest number and levels of single polyphenols. Conversely, the lower growth inhibitory activities found in chloroform and diethyl ether extracts could be related to the isolation of minor lipid classes (e.g., neutral and medium polar lipids) composed by fatty acids, such as stearic, oleic and arachidonic acids, typically characterized by antimicrobial activity. In consideration of the results obtained, the present study has a double implication, involving both the field of cultural practices and the exploitation of natural sources for the isolation of antimicrobial agents useful both in pharmaceutical and food applications.

New Insights into the Culture Method and Antibacterial Potential of Gracilaria gracilis.

The aim of this study was to prepare crude extracts from the leaves of Ficus sycomorus ( F. sycomorus ) native to Oman, and determine their total flavonoids content as well as their antimicrobial activity. Powdered leaf samples were extracted with methanol by using maceration method. The resulting crude extract was suspended in water and successively extracted with hexane, chloroform, ethyl acetate and butanol solvents, respectively. Total flavonoids of the above extracts were determined by the aluminum chloride method, and antimicrobial activity of the same extracts was assessed by a slightly modified disc diffusion method against different Gram (+ and −) bacterial strains. The highest flavonoids content was found in chloroform crude extract followed by that of hexane, butanol, ethyl acetate, and water extracts, respectively. Tested against four bacterial strains, the extracts showed activity in the range of 0–12 mm, using amoxicillin as standard. The present findings could establish this plant as a potential source of antibiotics.

Total flavonoids content and antimicrobial activity of crude extract from leaves of Ficus sycomorus native to Sultanate of Oman

This study investigated the effects of dietary Sargassum ilicifolium on growth performance, hematological parameters, immune responses, and protection against Yersinia ruckeri challenge in great sturgeon, Huso huso. The fish (56.8 ± 4.1 g) were fed diets containing four concentrations of S. ilicifolium (0 (basal diet), 5, 7.5, and 10%) for 8 weeks. Growth parameters were significantly (p < 0.05) higher in 10% S. ilicifolium fed group after 8 weeks of feeding trial. The same group contained significantly higher serum immunological activities such as serum total protein, lysozyme, immunoglobulin M, respiratory bursts, and complement activities. Among hematological parameters, hemoglobin levels, red blood cells, and white blood cells were significantly higher in group supplemented with 10% of S. ilicifolium. Administration of S. ilicifolium had no significant effects on blood biochemical parameters such as triglycerides, lactase dehydrogenase, aspartate aminotransferase, and alanine aminotransferase activities. However, 10% S. ilicifolium supplementation significantly lowered blood cholesterol levels. Furthermore, fish fed 10% S. ilicifolium supplemented diet exhibited the highest (p < 0.05) relative post-challenge survival (75.2%) against Y. ruckeri infection. Overall, these results suggest that dietary supplementation of S. ilicifolium (at 10%) can promote growth and strengthen immunity of great sturgeon.

Effects of dietary algae (Sargassum ilicifolium) as immunomodulator and growth promoter of juvenile great sturgeon (Huso huso Linnaeus, 1758)

Several hundreds of plant genera are used medicinally and plants are vital sources for potent and powerful drugs. The present study was conducted to screen the pharmacological activity of the ethanol and acetone extract of Phyllanthus amarus, Acalypha and indica Datura metel for its antimicrobial activity against selected pathogen. The bacterial Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa and Bacillus subtilis. The fungal Aspergillus niger and Penicilliumsp. The collected leaf samples were powdered and the bioactive compounds were extracted by using ethanol and acetone in a Soxhelet extractor. The antimicrobial activity was determined by using Disc diffusion method. Ethanol and acetone extracts with different concentrations (100mg/ml, 200mg/ml and 300mg/ml) were mixed with 1 ml of Dimethyl sulfoxide (DMSO). The inhibitory effect of ethanol extract was relatively high when compared to acetone extract. The study of antimicrobial activity of herbal plant extract of Datura metel, Acalypha indica and Phyllanthus amarus showed that the ethanol extract shows promising antimicrobial activity against bacterial and fungal human pathogens when compared to acetone extract. This study also encourages cultivation of the highly valuable plant in large scale to increase the economic status of the cultivators and provide a support to use of the plant in traditional medicine.

Screening of Phyllanthus amarus, Acalypha indica and Datura metel for its antimicrobial activity against selected pathogens

Seaweeds are the eukaryotic organisms that lives in salty water in the ocean and is recognized as a potential source of bioactive natural products. The present study was conducted to screen the pharmacological activity of Gracilaria edulis solvent extracts against human pathogenic bacteria and fungi. The seaweed Gracilaria edulis was extracted using the organic solvents viz., methanol, acetone, petroleum ether, hexane and ethanol. Antimicrobial activity of Gracilaria edulis solvent extract was determined by Disc diffusion method. Among the solvents tested, methanol extract of Gracilaria edulis showed maximum inhibitory activity than other solvents. The zone of inhibition of Gracilaria edulis methanol extract against bacteria was maximum against Gram positive cocci Streptococcus pyogenes followed by Bacillus subtilis, Staphylococcus aureus, Streptococcus epidermis and Bacillus cereus. For Gram negative bacteria, the maximum zone of inhibition was recorded in methanol extract of Gracilaria edulis against Klebsiella pneumoniae followed by Enterobacter aerogens, Salmonella typhi, Pseudomonas aeruginosa, Escherichia coli and Vibrio cholerae. For fungi, the zone of inhibition was maximum against Aspergillus flavus followed by Aspergillus fumigatus, Aspergillus niger, Candida albicans, Candida glabrata and Saccharomyces cerevisiae.

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Pharmacological Efficacy of Marine Seaweed Gracilaria edulis Extracts Against Clinical Pathogens

Ten mangrove medicinal plants viz., Avicennia marina, Rhizophora mucuronata , Rhizophora mangle, Asparagus officinalis, Ceriops decandra, Aegiceras corniculatum, Acanthus ilicifolius, Bruguiera cylindrica, Rhizophora apiculata and Xylocarpus grantum were collected from mangrove forest of Pichavaram, Tamil Nadu, India. The antibacterial activity of mangrove plant extracts (150 mg/ml and 300 mg/ml) were determined by Disc diffusion method. The zone of inhibition was more at 300 mg/ml of extracts when compared to 150 mg/ml of extracts. The antibacterial activity of selecte d mangrove plant leaf extracts was determined against pathogenic bacterial isolates. The methanol extract of Ceriops decandrashowed maximum zone of inhibition against all the bacterial isolates followed by Avicennia marina, Rhizophora mucronata , Aegiceras corniculatum, Rhizophora apiculata, Rhizophora mangle , Acanthus ilicifolius, Asparagus officinalis, Xylocarpus grantumand Bruguiera cylindrica at 300 mg/ml. The hexane extract of mangrove plants showed minimum inhibition zone against bacterial pathogens when compared to the other solvent extracts. The DMSO was used as a blind control and the antibiotic Ampicillin (300 mg/ml) was used as a positive control. Minimum inhibitory concentration (MIC) of the mangrove plant extracts against bacterial isolates was tested in Mueller Hinton broth by Broth macro dilution method. The MIC of mangrove plants against bacterial pathogens was ranged between 20 mg/ml to 640 mg/ml.

Annamalai Nagar

Papers

Screening of Phyllanthus amarus, Acalypha indica and Datura metel for its antimicrobial activity against selected pathogens

Pharmacological Efficacy of Marine Seaweed Gracilaria edulis Extracts Against Clinical Pathogens

Antibacterial activity of Mangrove Medicinal Plants against Gram positive Bacterial pathogens