Abstract Book - 3rd International Symposium on Medicinal Plants ...

1.7 High Inhibition Effect on Lipid Peroxydation by Phenolic Extracts from
Some Local Medicinal Plants
Amar DJERIDANE, Nourelhouda RENANE and Mohamed YOUSFI
Laboratoire des sciences fondamentales, Univ. Amar Telidji. PB 37 G, 03000, Laghouat- Algérie.
<strong>Abstract</strong>: Antioxidant activities and phenolic content of extract and solvent-solvent partition
fractions from the aerial parts of four medicinal plants were evaluated. Ariel parts of Asteriscus
pygmaeus, Hammada elegans, Plantago ciliate and Thymelia microphylla were extracted with
gradient polarity of different solvents. The extracts were then extracted by liquid-liquid partition
with different organic solvents to obtain sixteen fractions. Next, the phenolic content of all these
fractions were analysed by Folin-Ciocalteu method and their inhibition of peroxidation of linoleic
acid and sunflower oil were evaluated by lipid peroxideammonium thiocyanate method. The total
phenolic content of the different Hammada elegans fraction varied from 0.045 to 0.0714 mg/g dry
weight, expressed as gallic acid equivalents (GAE). Whereas, the percentage inhibition of
peroxidation of linoleic acid and sunflower oil was found to be higher in methanolic fraction, it was
comparable to α-tocopherol, trolox, BHT and BHA. In this study, a direct relationship between the
total phenolic content with inhibitory activity towards lipid peroxidation was observed. This
indicates that phenolics are the main contributors for the observed antioxidant activities for
different plants extracts. These results, suggest that the level of antioxidant activity in these plants
varies to a great extent. They also suggest that phenolics in these plants provide substantial
antioxidants. Upon achievement of this survey, and using more samples, extra benefits of these
medicinal plants may be completed. Flora of Algeria appears to be a rich and interesting source for
supplementary ethnomedicinal and phytochemical studies.
Key words: Hammada elegans, lipid peroxidation, phenolics, medidinal plants.
1.8 Antimicrobial and Antioxidant Activity of Fraxinus excelsior Extract
ARRAR Lekhmici 1 , AMAMRA Samra 1 , ZERROUG Mohammed Mihoub 2 ,
BELHADDAD Oum Elkheir 1 , CHAREF Noureddine 1 , KHENNOUF Seddik 3 ,
NICKLIN Jane 4 and BAGHIANI Abderrahmane 1
1 Laboratory of Applied Biochemistry, Faculty of Nature and Life Science, University Ferhat Abbas,
Setif. 2 Laboratory of Applied Microbiology, Faculty of Nature and Life Science, University Ferhat
Abbas, Setif. 3 Laboratory of Phytotherapy applied to Chronic diseases, Faculty of Nature and Life
Science, University Ferhat Abbas, Setif, Algeria. 4 School of Biological and Chemical Sciences,
Birkbeck College, University of London, UK.
<strong>Abstract</strong>: Medicinal preparations derived from natural sources, especially from plants, have
been in widespread use since time immemorial. In this study, oil extract of Fraxinus excelsior was
tested to evaluate its antioxidant effects and antimicrobial activity against twelve bacteria and three
phytopathogenic fungi. The results showed that the oil (petroleum ether) extract contained
moderate amount of polyphenols and flavonoids. DPPH test showed an EC 50 of 3722.5 ± 72.84
μg/ml. Using beta carotene/linoleic acid method, the oil extract of F. excelsior inhibits the lipid
peroxidation with an IC 50 of 70 % after 24 h which is a good effect. On the other hand petroleum
ether extract inhibited the growth of the tested microorganisms with different zones of inhibition
from 8 mm to 15 mm except for Lysteria monocytogenes, Salmonella typhimurium and the
bacteria isolated form human samples. The antimicrobial effect of this extract varied with
microorganism's species and its own concentration. Thus at the 12.5 mg/ml, an inhibition diameter
of 14 mm was recorded with Ascochyta rabiei and Fusarium solani f. sp. coeruleum and Fusarium
oxysporum f. sp. albedinis but only 8.7 mm for Candida albicans even at extract concentration of
25 mg/ml. The same phenomenon was observed with the antibacterial activity. A zone of inhibition
of 8 mm was observed with Staphylococcus aureus using the extract at 50 mg/ml. The
concentration of 25 mg/ml gave inhibition zones of of 10 mm, 9.3 mm and 8.5 for Enterococcus
faecalis, Acinetobacter baumanii and Salmonella typhimurium respectively. The 12.5 mg/ml
inhibited the growth of E. coli with 9.3 mm. At the 6.25 mg/ml, inhibition zones of 15 mm and 8 mm
was obtained for Bacillus cereus and Pseudomonas aeruginosa respectively.
Key words: Antibacterial, anti-fungal effects, antioxidant, Fraxinus, petroleum ether extract.
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