Caffeine is the most commonly used psychoactive substance throughout the world. It is found in coffee, black tea, and chocolate, as it is produced naturally in the beans and leaves of the plants used to manufacture these products. This study aimed to make a survey study among children 2-11 years in some Tripoli, Libya schools to determine caffeine concentration in number of beverages and foods consumed by studied children. About 313 copies of the questionnaire were distributed to students to be filled by their parents. Caffeine was extracted from samples using dichloromethane. Purity of isolated caffeine was estimated by using TLC method.Quantitative analysis of caffeine was performed by using a UV-Visible spectrophotometer. Chocolate biscuits, chocolate cake, cocoa milk and chocolate ice cream were the highest consumed products among the studied children (81%, 79%, 67% and 63% respectively). The highest side effects of caffeine consumption was hyperactivity was the highest side effect in children (76%). Some children also suffered from severe side effects such as panic attack (14%). Naseem ice cream sample showed the highest caffeine content (28 mg/serving) among solid samples.Whereas in the beverages, energy drink samples Red pull, XIR and Shark were 268, 262 and 250 mg/serving respectively. In conclusion, there was excessive consumption of caffeine among the studied group of children and some of them showed side effects and even severe side effects. Variety of tested foods and beverages under the study contained uncontrolled concentrations of caffeine. In addition, chocolate milk (Al Rayhan), contained no caffeine. arabic 15 English 97
Sakina S. Saadawi, Khairi A. Alennabi, AMAL .A ABOALLA AMMAR, , , ٍSuhera Mehemed Abdulsalam Aburawi(9-2019)

The antibacterial activity of peppermint oil and different extracts of Mentha piperita against some Gram-positive and Gram-negative bacterial strains was evaluated in the present research work by agar well diffusion method. It was found that the distilled concentrations of essential oil inhibited the growth of microorganisms and the results were comparable with those of antibiotic gentamycin. Essential oils showed a wider spectrum of activity but less strong inhibition as compared to the investigated commercial antibiotic. Minimum inhibitory concentrations (MICs) for the bacterial species ranged from 0.4% to 0.7% v/v. The oil and extracts also exhibited significant antioxidant activity and the oil showed about half potency when compared to the standard BHT. These results indicated the strong antibacterial and antioxidant activities of peppermint oil but additional investigations need to be performed in order to confirm the safety of these concentrations (MIC) for human consumption. Peppermint oil could be used as a good conservation agent by inhibiting some food borne pathogens. arabic 8 English 54
Rajinder Singh, Muftah A. Shushni, Asma Belkheir(5-2015)

Hydroxyethylrutosides (Troxerutin) is a standardized mixture of semi-synthetic flavonoids obtained by substituting hydroxyethyl groups in the naturally occurring flavonol rutin. Because there are four dissociation hydroxyls in rutin, some fifteen kinds of hydroxyethylrutins can be theoretically synthesized. The good quality of the raw material of a drug and the finished product must include the related impurities in an analytical investigation, and this seemed particularly important to the quality control of Troxerutin. According to the literature, it is clear that, the chromatographic analysis of Troxerutin still problematic as its sample can be considered as a complex sample as it contains plenty of different components. In this study, new HPLC technology named fused- core column was used to separate the major components of Troxerutin bulk powder. Fused – Core silica stationary phases represent key technological advancement in the area of fast HPLC separations. These phases are made by fusing 0.5 μm porous silica. The reduced intra – particle flow path of the fused particles provides superior mass transfer kinetics and better performance at high mobile phase velocities, while the fused – core particles provide lower pressure than sub – 2 μm particles. arabic 13 English 77
Sakina Salem Mohammed Saadawi, AMAL .A ABOALLA AMMAR, Mohamed Nouri Mansour El Attug, Amal Khalifa Ali Belaid, ٌRuwida Mohamed Ali Kamour, Tariq Khalifa Masoud Almog(1-2016)