Antioxidant activity of water-soluble polysaccharide extracted from Eucalyptus cultivated in Lebanon

Objective To extract and identify the chemical composition of the polysaccharide isolated from the Eucalyptus cultivated in Lebanon and to evaluate its antioxidant activity. Materials The water-soluble polysaccharide was isolated from Eucalyptus leaves, and its structure was identified by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, and carbon-13 nuclear magnetic resonance. The antioxidant activity of the active ingredient was screened for its radical scavenging ability using 2,2-diphenyl-1-picryl-hydrazyl radical (DPPH) test. Results The results of the DPPH test have shown that fucoidan, the polysaccharide isolated from Eucalyptus, exhibited almost the same antioxidant activity against DPPH· as the ascorbic acid did at 100 μg/mL. Conclusions This natural molecule extracted from a medicinal plant has a promising antioxidant activity and could be used in pharmaceutical and medical applications.

Antibacterial and antibiofilm activities of polysaccharides, essential oil, and fatty oil extracted from Laurus nobilis growing in Lebanon

OBJECTIVE@#To evaluate the antibacterial activity of the extracts of Laurus nobilis against three Gram-positive bacteria (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212 and Staphylococcus epidermidis CIP 444) and two Gram-negative bacteria (Escherichia coli ATCC 35218 and Pseudomonas aeruginosa ATCC 27853). Also, the antibiofilm activity has been investigated against the biofilm produced by Staphylococcus epidermidis CIP 444.@*MATERIALS@#The polysaccharides, essential oil, and fatty oils extracted from the plant were used in broth microdilution methods to study the minimal inhibitory concentration, and then the minimal bactericidal concentration was determined.@*RESULTS@#The results showed that alginate, fucoidan, fatty oils and essential oil have good antibacterial activities against the 5 bacterial strains, and a negligible biofilm eradication activity of fucoidan, laminaran, fatty oil, and essential oil was observed, but a promising biofilm eradication activity was obtained with alginate, which showed a reduced biofilm mass even at low concentration.@*CONCLUSIONS@#The extracts obtained have promising antibacterial capacities which need further investigation for them to be incorporated in medical or nutritional applications.

Antibacterial and antibiofilm activities of polysaccharides, essential oil, and fatty oil extracted from Laurus nobilis growing in Lebanon

Objective: To evaluate the antibacterial activity of the extracts of Laurus nobilis against three Gram-positive bacteria (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212 and Staphylococcus epidermidis CIP 444) and two Gram-negative bacteria (Escherichia coli ATCC 35218 and Pseudomonas aeruginosa ATCC 27853). Also, the antibiofilm activity has been investigated against the biofilm produced by Staphylococcus epidermidis CIP 444. Materials: The polysaccharides, essential oil, and fatty oils extracted from the plant were used in broth microdilution methods to study the minimal inhibitory concentration, and then the minimal bactericidal concentration was determined. Results: The results showed that alginate, fucoidan, fatty oils and essential oil have good antibacterial activities against the 5 bacterial strains, and a negligible biofilm eradication activity of fucoidan, laminaran, fatty oil, and essential oil was observed, but a promising biofilm eradication activity was obtained with alginate, which showed a reduced biofilm mass even at low concentration. Conclusions: The extracts obtained have promising antibacterial capacities which need further investigation for them to be incorporated in medical or nutritional applications.

Macroelements of fucus vesiculosus, in Lebanon

Marine algae contain essential elements for human organism, like carbohydrates, proteins and lipids. In most of algae, the percentage of those elements exceeds that of potatoes, corns, cabbages and others. A number of algae even contain the same quantity of ascorbic acid contained in lemon, orange or chive. The extracted and then filtered elements of marine algae can be used as food additives, in the pharmaceutical industry, as well as in the fabrication of paper, ink, alcohol, nitrocellulose, acetone, glycerin, soap, plastic…etc. they can be also added in animal food. Algae biological composition differs from that of plants growing on the surface; their photosynthesis is 5 or 7 times faster, and this is why they can grow at a considerable speed [15-60 cm/day]. Given their importance, marine algae became an object of many largescale studies, in a number of countries, in order to be used in every possible domain. Today China, for example, collects more than 1.5 m tonnes of Laminaria each year, as well as Japan [3 m tonnes] and other countries like Russia, Ukraine, France...etc. In our project, it was impossible for us to study all kinds of algae at a time; this is why we decided to start with Fucus Vesiculosus. After determining all the places [on the Lebanese coast] where this plant grows [Kfar-Ebeid, Gisr El-Madfun, El-Barbara, Al-Munsef, Amshit, Al-Helwa], we found that it starts growing in May and disappears in late August. The best time to collect those algae is July, for they are rich in active ingredients. This is exactly what we did on the El-Barbara coast. The following tests were conducted afterwards: 1- Determining the quantity of amino acids. 2- Determining the quantity of lipids