ِAbdulatif Asheg, Khalid Fathi Almasri (1-2020)

Natural products including alkaloids from algae may provide alternative source for new natural antioxidants due to their novel structure. In the present study the antioxidant properties of alkaloids extracted from Sargassum hornschuchii and Cystoseira compressa were assessed using various in vitro systems including 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide, hydroxyl radicals, nitric oxide (NO) scavenging, phosphomolybdenum reduction and reducing power activity at different concentrations (6.25 to 100 mg/ml). The results showed that alkaloids rich extracts exhibit antiradical activity and reduction ability in concentration dependent. Extracts exhibit significant low scavenging activity on DPPH and nitric oxide radical activity Investigation … Rabia Alghazeer et al. compared to standard, ascorbic acid and butylated hydroxyanisole (BHA). Reducing power and total antioxidant of extracts showed less effect compared to standard, ascorbic acid and butylated hydroxyanisole (BHA). Superoxide, and hydroxyl radical assays showed a comparable scavenging activity compared to its standard. Therefore, new separation, purification techniques, and powerful identification methods are recommended to improve their antioxidant activity.
Salah M. Azwai(1-2019)

Aim: The aim of this work was to isolate and molecularly identify enterohemorrhagic Escherichia coli (EHEC) O157 in milk and dairy products in Libya, in addition; to clear the accuracy of cultural and biochemical identification as compared with molecular identification by partial sequencing of 16S rDNA for the existing isolates. Materials and Methods: A total of 108 samples of raw milk (cow, she-camel, and goat) and locally made dairy products (fermented cow’s milk, Maasora, Ricotta and ice cream) were collected from some regions (Janzour, Tripoli, Kremiya, Tajoura and Tobruk) in Libya. Samples were subjected to microbiological analysis for isolation of E. coli that was detected by conventional cultural and molecular method using polymerase chain reaction and partial sequencing of 16S rDNA. Results: Out of 108 samples, only 27 isolates were found to be EHEC O157 based on their cultural characteristics (Tellurite-Cefixime-Sorbitol MacConkey) that include 3 isolates from cow’s milk (11%), 3 isolates from she-camel’s milk (11%), two isolates from goat’s milk (7.4%) and 7 isolates from fermented raw milk samples (26%), isolates from fresh locally made soft cheeses (Maasora and Ricotta) were 9 (33%) and 3 (11%), respectively, while none of the ice cream samples revealed any growth. However, out of these 27 isolates, only 11 were confirmed to be E. coli by partial sequencing of 16S rDNA and E. coli O157 Latex agglutination test. Phylogenetic analysis revealed that majority of local E. coli isolates were related to E. coli O157:H7 FRIK944 strain. Conclusion: These results can be used for further studies on EHEC O157 as an emerging foodborne pathogen and its role in human infection in Libya.
Salah M. Azwai(1-2016)