Aflatoxin B1 in eggs and chicken livers by dispersive liquid-liquid microextraction and HPLC.

A rapid, low-cost and simple technique has been developed for the determination of aflatoxin B1 (AFB1) in eggs and livers using high-performance liquid chromatography (HPLC) with UV detection. In this study, the presence of AFB1 was investigated in 150 eggs and 50 chicken livers from the local market of Tabriz, Iran. AFB1 was extracted with a mixture of acetonitrile:water (80:20) and cleaned up by dispersive liquid-liquid microextraction which is a very economical, fast and sensitive method. AFB1 was quantified by HPLC-UV without need for any complex derivatisation in samples to enhance the detection. The results showed that 72% of the liver and 58% of the egg samples were contaminated with AFB1 ranging from 0.30 to 16.36 µg kg (̶1). limit of detection and limit of quantification for AFB1 were 0.08 and 0.28 µg kg (̶ 1), respectively. The proposed method is suitable for fast analysing of AFB1 in egg and liver samples.

Amino Acid profile as a feasible tool for determination of the authenticity of fruit juices.

PURPOSE: Fruit juice is a nutrient rich food product with a direct connection to public health. The purpose of this research was to determine the amino acid profile of juices and provide a quick and accurate indicator for determining their authenticity. METHODS: The method of analysis was HPLC with fluorescence detector and pre-column derivatization by orthophtaldialdehyde (OPA). Sixty-six samples of fruit juices were analyzed, and fourteen amino acids were identified and determined in the sampled fruit juices. The fruit samples used for this analysis were apples, oranges, cherry, pineapple, mango, apricot, pomegranate, peach and grapes. RESULTS: The results showed that 32% of samples tested in this study had a lower concentrate percentage as compared to that of their labels and/or other possible authenticity problems in the manufacturing process. The following samples showed probable adulteration: four cherry juice samples, two pomegranate juice samples, one mango, three grape, four peach, seven orange, two apple and one apricot juice samples. CONCLUSION: In general, determining the amount of amino acids and comparing sample amino acids profiles with the standard values seems to be an indicator for quality control. This method can provide the regulatory agencies with a tool, to help produce a healthier juice. The aim of this study is the analytical control of the fruit juice composition is becoming an important issue, and HPLC can provide an important and essential tool for more accurate research as well as for routine analysis.

Circulating phospholipase-A2 activity in obstructive sleep apnea and recurrent tonsillitis.

OBJECTIVE: Phospholipase A2 (PLA2) plays a major part in growth regulation, differentiation and inflammation. It has been proposed as an evaluating marker for infection and inflammation. The aim of this study was to investigate activity of serum type II secretory PLA2 (sPLA2 IIa) in obstructive sleep apnea (OSA) and recurrent infective tonsillitis (RT) in children. METHODS: Activity of serum sPLA2 IIa was determined in children who underwent tonsillectomy, including OSA in 126 cases and RT in 60. Serum enzyme activities were measured using the standard assay with Diheptanoyl Thio-Phosphatidylcholin as substrate. RESULTS: The sPLA2 IIa activity of serum was significantly higher in RT than in OSA (P<0.01). Serum sPLA2 IIa activity in the RT patients was positively correlated with BMI (r=0.26; P=0.02), which was not apparent in OSA (r=0.14; P=0.09). CONCLUSION: This study suggests that serum sPLA2 IIa activity may be considered as a supportive diagnostic marker in suspected or clinically unclear cases of RT children.

Determination of aflatoxins in nuts of Tabriz confectionaries by ELISA and HPLC methods.

PURPOSE: Aflatoxins (AFs) are a group of mycotoxins and secondary metabolites of various species of Aspergillus. There are various forms of aflatoxins including B1, B2, G1, G2, M1 and M2 types. Aflatoxins cause important health problems and have high potential effect on liver cancer. Therefore, numerous investigations have been conducted during last three decades. The aim of this work is to determine the contamination levels of nuts used by the confectionaries in Tabriz. METHOD: A total of 142 samples including 35 almond , 26 walnut, 4 seeds of apricot, 6 sunflower seeds kernel, 6 sesame seed, 6 peanuts , 32 pistachio,13 hazelnuts and 14 cashews samples were collected from Tabriz confectionaries. The ELISA method was employed for the screening of total aflatoxins. RESULT: In 13 cases (28.1% of pistachios, 5.1% of walnuts and 7.1% of cashews) contamination rate of higher than 15 ppb were observed. The HPLC method was applied for the confirmation of ELISA results. Aflatoxin B1 was the highest detected AFs. CONCLUSION: The overall results of the tested samples indicated that the rate of contamination of pistachios is higher than the other tested samples.

Solid-Phase Extraction and Simultaneous Determination of Tetracycline Residues in Edible Cattle Tissues Using an HPLC-FL Method.

In this assay, edible cattle tissues from local markets of Ardabil, a Province of Iran, were examined for residues of tetracycline antibiotics (tetracycline, oxytetracycline and chlortetracycline). In total, 110 samples of triceps, gluteal muscle, diaphragm, kidney and liver were randomly obtained from the local markets of the city of Ardabil. Solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) methods were used to extract and analyze tetracycline antibiotic (TC) residues, respectively. The mean amount of total TC residues in all tested samples was 226.3 ± 112.5 ng/g and the mean amount of the total TC residues in triceps, gluteal muscle, diaphragm, kidney and liver samples were 176.3 ± 46.8, 405.3 ± 219.6, 96.8 ± 26.9, 672.4 ± 192.0 and 651.3 ± 210.1 ng/g, respectively. Additionally, 25.8% of muscle samples, 31.8% of liver samples and 22.7% of kidney samples contained amounts of TC residues beyond the maximum residue limit (MRLs). To reduce the TC residues found in edible cattle tissues, regulatory authorities should ensure that the cattle would undergo the proper withdrawal period from TCs before the slaughtering.

Simultaneous Determination of Tetracyclines Residues in Bovine Milk Samples by Solid Phase Extraction and HPLC-FL Method.

INTRODUCTION: Tetracyclines (TCs) are widely used in animal husbandry and their residues in milk may resultin harmful effects on human. The aim of this study was to investigate the presence of TCs residues in various bovine milk samples from local markets of Ardabil, Iran. METHODS: One hundred and fourteen pasteurized, sterilized and raw milk samples were collected from markets of Ardabil. Tetracycline, Oxytetracycline and Chlortetracycline (TCs) residues extraction carried out by Solid Phase Extraction method. Determination of TCs residues were performed by high performance liquid chromatography (HPLC) method using Fluorescence detector. RESULTS: The mean of total TCs residues in all samples (114 samples) was 97.6 ±16.9ng/g and that of pasteurized, sterilized and raw milk samples were 87.1 ± 17.7, 112.0 ± 57.3 and 154.0 ± 66.3ng/g respectively. Twenty five point four percent of the all samples, and 24.4%, 30% and 28.6% of the pasteurized, sterilized and raw milk samples, respectively had higher TCs residues than the recommended maximum levels (100ng/g). CONCLUSION: This study indicates the presence of tetracycline residues more than allowed amount. Regulatory authorities should ensure proper withdrawal period before milking the animals and definite supervisions are necessary on application of these drugs.