systematic review on exposure to toxic and essential elements through black tea consumption in Iran: could it be a major risk for human health?

Tea is the most popular nonalcoholic beverage worldwide. In recent years, some Iranian studies have shown the occurrence of toxic elements in fresh or dried tealeaves as well as in brewed tea. The present study aimed to ascertain the health risks associated with exposure to toxic and essential element through black tea consumption in Iran by systematically reviewing the accredited articles in the field. In order to obtain the relevant articles and academic databases, the search engines covering the specifi c disciplines were searched for the keywords, including tea, elements, heavy metals and determination. Having provided the complete list of sound articles, being conducted in Iran was considered as the inclusion criteria. Exclusion criteria were established as failure to provide information on the validity parameters and accuracy in the analytical methods. Choosing well conducted, reliable studies, analytical results for the concentration of each element in black tea were utilized in the determination of the hazard quotient [HQ] for the given element and the hazard index [HI] was then determined for all of the elements in each study. Among the total studies, two were considered to be reliable. Aluminum was found to be the most abundant element in black tea marketed in Iran. Although the HQ for manganese was the highest among the studied elements, HQ and HI values for both toxic elements and essential elements were calculated as less than 1. The hazard of excessive element intake through black tea consumption should be considered as negligible in Iran. However, related risk for manganese appeared to be more than toxic metals

effect of neutral oligosaccharides on reducing the incidence of necrotizing

Necrotizing enterocolitis [NEC] is one of the most destructive diseases associated with conditions of neonatal prematurity. Supplementation with enteral prebiotics may reduce the incidence of NEC, especially in infants who fed exclusively with breast-milk. Therefore, we compared the efficacy and safety of enteral supplementation of a prebiotic mixture [short chain galacto-oligosaccharides/long chain fructooligosaccharides [SCGOS/LCFOS]] versus no intervention on incidence of NEC in preterm infants. In a single-center randomized control trial 75 preterm infants [birth weight [BW]

Simultaneous determination of sodium benzoate, potassium sorbate and natamycin content in Iranian yoghurt drink [Doogh] and the associated risk of their intake through doogh consumption

Regarding the public health concerns over the use of food preservatives in yoghurt drink "Doogh", the aim of this study was the determination of sodium benzoate, potassium sorbate and natamycin in Doogh. Based on Iranian national standard, none of these preservatives are permitted to be used in Doogh. A total of 39 Doogh samples were analyzed through RP- HPLC in order to quantify sodium benzoate, potassium sorbate and natamaycin simultaneously. Exposure to each preservative is estimated by mean and maximum concentrations as the residue levels. The per capita Doogh consumption was calculated by the published data from official reports for Doogh annual production in Iran. All samples were shown to contain sodium benzoate while natamaycin was detected in 10.25% of the samples and potassium sorbate was not detected in any of them. Sodium benzoate concentration extremely varied among the investigated samples ranged from 0.94 to 9.77 mg/l. Due to the result of the exposure estimation, no serious public health concern would exist regarding the mentioned preservatives. The detection of sodium benzoate in all Doogh samples could indicate the natural production of benzoic acid in yoghurt. Sodium benzoate may be formed through the interaction of the added food grade salt to the Doogh formula which contains benzoic acid. The results of exposure estimation show the lack of health risk within the usage of preservatives in spite of the national agencies does not permit the preservative use

How much in vitro cholesterol reducing activity of lactobacilli predicts their in vivo cholesterol function?

Based on literature, in vitro cholesterol removal of lactic acid bacteria has been accounted for their in vivo cholesterol reduction. But recently, it has been proposed that such in vitro characteristic may not be directly relevant to their in vivo activity. The objective of this study was to find how much in vitro cholesterol reducing potential of Lactobacillus plantarumA7 [LA7], a native strain isolated from an infant fecal flora, reflects its in vivo efficiency. LA7 previously showed serum cholesterol reducing capability in mice subjected to fatty diet. Here, we investigate whether the given strain is capable of in vitro cholesterol assimilation or consumption. LA7 was cultured in whole milk and de-Man-Rogosa- Sharpe [MRS] added with water-soluble cholesterol. Colorimetric method was adopted for cholesterol determination in both cultured media during incubation period. No cholesterol assimilation was detected by growth and incubation of the active culture in either of the medium. Thus, in vivo cholesterol function of LA7 was not caused by cholesterol consumption. A comprehensive review of literature on the related studies also showed that there are other documented studies' evidenced the uncertainty of the direct relation between in vitro and in vivo studies. Cholesterol removal from the cultured media may not be considered as an appropriate integral index for selection of Lactobacillus strains with cholesterol-lowering activity

Investigation of acid and bile tolerance of native lactobacilli isolated from fecal samples and commercial probiotics by growth and survival studies

This study aimed at applying both growth and survival approaches to compare three native strains of lactobacilli, belonging to Lactobacillus plantarum, Lactobacillus rhamnosus and Lactobacillus acidophilus species, with two commercial probiotic strains in their tolerance to acid and bile. The association between the data obtained from the methods was studied. The results of the different methods applied in this study, did not confirm each other for all the examined strains. However, the native strain of L. plantarum and the commercial strain of L. acidophilus repeatedly demonstrated the most and least bile resistances, respectively. The former excelled in all growth approaches but showed moderate acid resistance in the survival studies. Bile stress seemed to have more detrimental effects on all examined strains. The overall results suggest that the growth-rate designed studies and survival studies evaluating transit tolerance, might bring up different results when the examined strains belong to different species of lactobacilli showing different growth and metabolic activities. The strain of L. plantarum examined here could thus be considered as a potential probiotic, regarding its overall resistance to acid and bile

Identification of lactobacilli from fecal flora of some Iranian infants

During the past 20 years identification of lactobacilli isolated from normal flora has received great interest due to their health promoting effects. This study has aimed at characterizing the lactobacillus strains isolated from the fecal flora of Iranian infants based on phenotypic oriented methods. Moreover, the diversity of identified species among tested infants has been looked into. Thirty two strains of lactobacilli were included in this study. The given strains were previously isolated from the fecal samples of 6 infants between 1-19 months of age. They are examined through 14 carbohydrate fermentation tests, growth ability at different temperatures and different concentrations of NaCl. Cell and colony morphology were assessed as well. The examined strains were identified as L. acidophilus [12 strains], L. plantarum [9 strains], L. rhamnosus [7 strains], L. paracasei [3 strains] and L. fermentum [1 strain]; 2 strains remained unidentified. Accordingly L. acidophiluswas the most predominant species among tested samples. Some biochemical differences were obtained among the strains of L. acidophilus group and some morphological peculiarities were observed among the strains of L. paracasei and L. rhamnosus in comparison to the typical strains of L. casei group. These differences revealed the necessity of application of complementary molecular methods for clear identification of examined Lactobacillus strains