Content of toxic and essential metals in recrystallized and washed table salt in Shiraz, Iran

BACKGROUND: Table salt is the most commonly used food additive. Since most of the salt consumed in Iran comes from mines, contamination with heavy metals is a health concern. The commonest salt purification method in Iran is washing with water. But recently, some industries have turned to recrystallization method. The present study aimed to determine the level of essential and non-essential heavy metals in the table salt refined with recrystallization and washing methods. METHODS: Thirty eight pre-packed salt samples were directly collected from retail market in Shiraz (22 samples refined with recrystallization method and 16 with washing method). The level of lead, cadmium, copper, zinc, nickel and cobalt was determined using Voltammetric method. Daily intakes of lead and cadmium as well as their weekly intakes were calculated. RESULTS: The levels of lead, cadmium, copper, zinc, nickel and cobalt in recrystallized samples were 0. 30 ± 0.26, 0.02 ± 0.02, 0.11 ± 0.06, 0.34 ± 0.22, 0.15 ± 0.19 and 0.008 ± 0.007 μg/g, respectively, and also 0.37 ± 0.27, 0.017 ± 0.021, 0.19 ± 0.18, 0.37 ± 0.20, 0.13 ± 0.23 and 0.037 ± 0.06 μg/g in washed salt samples. The calculated weekly intake of lead and cadmium was 0.216 and 0.014 μg/kg, respectively for the recrystallized and 0.2653 and 0.0119 μg/kg for the washed salts. CONCLUSION: All values for toxic metals were lower than the permitted maximum for human consumption as prescribed by Codex and Institute of Standards and Industrial Research of Iran. Only 0.8652-1.0612% of lead and 0.17-0.2% of cadmium PTWIs are received via salt consumption weekly

Anticancer, antioxidant, and antibacterial effects of nanoemulsion of Origanum majorana essential oil

Background and Objectives: This study aimed to develop a natural nanoemulsion with antibacterial and anticancer properties. Materials and Methods: The chemical composition of the Origanum majorana essential oil was investigated using GC–MS analysis. Besides, the successful loading of the essential oil in the nanoemulsion was confirmed using ATR-FTIR analysis. Moreover, nanoemulsion’s anticancer, antioxidant, and antibacterial activities were investigated. Results: Terpinen-4-o1 (46.90%) was identified as the major compound in the essential oil. The nanoemulsion with a 149 ± 5 nm droplet size and zeta potential of -11 ± 1 mV was prepared. The cytotoxic effect of the nanoemulsion against A-375 human melanoma cells (IC50 = 139 µg/mL) showed significantly more potency than A-549 human lung cancer cells (IC50 = 318 µg/mL). Interestingly, growth of Staphylococcus aureus (Gram-positive) and E. coli (Gram-negative) bacteria after treatment with 4800 µg/mL of nanoemulsion were obtained at 12 ± 2 and 6 ± 1%, respectively. However, the IC50 value of nanoemulsion against E. coli (580 µg/mL) was not significantly different (P > 0.05) from S. aureus (611 µg/mL). Conclusion: A straightforward preparation method, high stability, and multi-biological effects are the main advantages of the prepared nanoemulsion. Therefore it could be considered for further investigation in vivo studies or complementary medicine

Kinetic and thermodynamic studies of the removal of murexide from aqueous solutions on to activated carbon

Abstract The objective of this study was to assess the adsorption potential of activated carbon (AC) as an adsorbent for the removal of Murexide (Mu) from aqueous solutions. The influence of variables parameters including pH, amount of adsorbent, sieve size of adsorbent, temperature and contact time on Mu removal was studied. Following optimization of variables, the relation between concentrations of dye remained in aqueous and adsorbent has been evaluated using various adsorption isotherm models like, Langmuir, Freundlich, Tempkin, Harkins-Jura and Dubinin-Radushkevich. Thermodynamic parameters such as enthalpy (∆H • ), and, entropy (∆S • ), activation energy (E a ), sticking probability (S * ), and Gibb's free energy changes (∆G • ) were also calculated. It was found from evaluated different thermodynamic parameters, viz., ∆H • , ∆S • and ∆G • that the adsorption of Mu by AC was feasible, spontaneous and endothermic process. The kinetic studies suggest that the all process following pseudo second order kinetics and involvement of intera-particle diffusion mechanism. The results indicated that the intraparticle diffusion also is the rate limiting factor