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Acrylamide (AA) is a compound classified as carcinogenic to humans by the International Agency for Research on Cancer. It was first discovered to be present in certain heated processed food by the Swedish National Food Administration (SNFA) and University of Stockholm in early 2002. The major pathway for AA formation in food is the Maillard reaction between reducing sugar and the amino acid asparagine at high temperature. Since the discovery of AA's presence in food, many analytical methods have been developed for determination of AA contents in different food matrices. Also, several studies have been conducted to develop extraction procedures for AA from difficult food matrices. AA is a small, highly polar molecule, which makes its extraction and analysis challenging. Many articles and reviews have been published dealing with AA in food. The aim of the review is to discuss AA formation in food, the factors affecting AA formation and removal, AA exposure assessment, AA extraction and cleanup from food samples, and analytical methods used in AA determination, such as high-performance liquid chromatography (HPLC) and gas chromatography (GC). Special attention is given to sample extraction and cleanup procedures and analytical techniques used for AA determination.

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Simple and efficient high performance liquid chromatography (HPLC) with photodiode array (PDA) and fluorescence (FLD) detection methods have been validated for determination of taurine in energy drinks. These methods are based on pre-column derivatization of taurine with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) at alkaline medium to form colored fluorescent product. In the both validated HPLC methods, the derivatization product is separated on Intersil ODS-3 analytical column with acetonitrile and 0.1% trichloroacetic acid (30:70, v:v) as mobile phase. The eluted derivative is detected at 472 nm for HPLC-PDA and 472 nm/530 nm (Ex/Em) for HPLC-FLD. The methods were validated in terms of linearity, limit of detection (LOD), limit of quantification (LOQ), precision and accuracy (recovery). Good linearities were achieved for taurine (r 2 > 0.9998 and 0.9993) in the concentration range of 5-50 mg L-1 and 5-50 µg L-1 for HPLC-PDA and HPLC-FLD respectively. The LODs were 0.296 and 0.616 × 10-3 mg L-1 for HPLC-PDA and HPLC-FLD respectively. The precision for peak area were 0.78 and 0.61% for HPLC-PDA and HPLC-FLD respectively. Recoveries of taurine ranging from 92-103.3%), (n = 3) were obtained. The validated method was successfully applied for the determination of taurine in some selected energy drinks available in local markets.

The supramolecular interaction of anthracene (ANT) and phenanthrene (PHN) with cucurbit[n]uril, CB [n] (n = 6-8) has been investigated in aqueous media for the first time. The inclusion complexes were investigated and characterized by fluorescence spectroscopy, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry, and 1HNMR. The stability of these complexes and the mode of inclusion in aqueous media at atomistic levels were monitored by molecular dynamic (MD) simulations. The results obtained from the experimental and MD studies have demonstrated the formation of stable 1 : 1 complexes between the two guests with all hosts in aqueous media. From the fluorescence study, the binding constants of PHN with CB[6], CB[7], and CB[8] were found to be 398 � 63, 544 � 128, and 655 � 162 M À 1 , respectively. Whereas, ANT-CB[n] formation constants are 213 � 37 M À 1 270 � 35 M À 1 , and 356 � 94 M À 1 for CB [6], CB[7], and CB[8], respectively. The results obtained show that the size of the cavity of the macrocycle and the polarity of the rim play an important role in the stability of the formed complex. Surprisingly, CB[6] forms an inclusion complex with ANT while it interacts by its side with PHN through dipole-dipole interaction. The larger cavity sizes of CB[7], CB[8], were found to encapsulate the two guests forming highly stable inclusion complexes.

Punica granatum L. (Pomegranate) is a plant belongs to Lythraceae family. The objective of this study was to evaluate the antimicrobial activity of  petroleum ether, chloroform , acetone, ethyl acetate and ethanol extracts from the peel fruit of Punica granatum against standard microorganism.  This plant has been used as a traditional treatment for several diseases such as microbial infections. Extracts were evaluated for their effectiveness against four bacterial strains including both Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria as well as fungal species (Candida albicans and Aspergillus niger) using disc diffusion method. The ethyl acetate, acetone and petroleum ether extracts showed higher antibacterial activity than the chloroform and ethanol extracts with inhibition zone ranged between (7-16 mm). The petroleum ether and chloroform extracts showed the higher antifungal activity compared with the other extracts, the diameter inhibition zone ranged between (11-16 mm). The antioxidant potential of peel extracts was determined on the basis of their scavenging activity of the stable 1, 1-diphenyl-2-picryl hydrazyl (DPPH) free radical and 2,2'azino-bis(ethyl benzthiazoline -6-sulfonic acid (ABTS+). All extracts showed high antioxidant activity . The highest result of antioxidant activity by DPPH scavenging assay was in acetone extract (89.40%), but high result by ABTS in ethanol extract (72.07%). KEYWORDS:

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