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An HPLC method with ultraviolet-visible spectrophotometry detection has been optimized and validated for the simultaneous determination of phenolic compounds, such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as antioxidants, and octyl methyl cinnamate (OMC) as UVB-filter in several personal care products. The dynamic range was between 1 to 250 mg/L with relative standard deviation less than 0.25% (n = 4). Limits of detection for BHA, BHT, and OMC were 0.196, 0.170, and 0.478 mg/L, respectively. While limits of quantification for BHA, BHT, and OMC were 0.593, 0.515, and 1.448 mg/L, respectively. The recovery for BHA, BHT, and OMC was ranged from 92.1–105.9%, 83.2–108.9%, and 87.3–103.7%, respectively. The concentration ranges of BHA, BHT, and OMC in 12 commercial personal care samples were 0.13–4.85, 0.16–2.30, and 0.12–65.5 mg/g, respectively. The concentrations of phenolic compounds in these personal care samples were below than maximum allowable concentration in personal care formulation, that is, 0.0004–10 mg/g, 0.002–5 mg/g, and up to 100 mg/g for BHA, BHT, and OMC, respectively.

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Plant sterols are belong to triterpenes family of natural products which includes more than 200 different types of plant sterols and more than 4000 other types of triterpenes. The optimization of method, specially the derivatization step as well as the corresponding analytical validation, is the main goal of this study. The optimum temperature, time and reagent volume of derivatization step were obtained at 60°C, 60 minutes and 50 µL, respectively. A rapid and sensitive gas chromatographic-mass spectrometric method was developed and validated for quantitative analysis of the most common plant sterols (β-sitosterol, campesterol and stigmasterol) in 20 Turkish bread wheat cultivars using GC-MS-SIM. Separation of β-cholestanol (I.S), campesterol, stigmasterol and β-sitosterol was achieved on Rxi (5Sil MS) column (60 m×0.25 mm). The limits of detection for β-sitosterol, campesterol and stigmasterol were 0.074, 0.054 and 0.064 mg kg

Honey produced by bees from nectar in flowers and plants, is an aqueous supersaturated sugar solution, mainly monosaccharide (fructose and glucose) (70%–80%) and water (10%–20%). 5-Hydroxymethylfurfural (5-HMF) content in honey bee is an indicator of the purity. High concentration of 5-HMF in honey bee indicates overheating and poor storage conditions (The chemical properties of honey, free acids and total acids) significantly in correlation with the HMF content and provides parameters that are used to make quick assessments of honey quality (Khalil et al., 2010). The recommended value of 5-HMF (Alinorm 01/25, 2000) and the European Union (Directive 110/2001) in honey usually should not exceed 80 or 40 mg/kg, respectively. This work aims to examine the concentration of 5-Hydroxymethylfurfural (5-HMF) content in different Qatari honey bee samples as an indicator of the honey bee quality by using the reference White Method.

A new method was developed to determine pesticide residues in fruit and vegetable extracts with short time analysis. An optimum results were achieved using binary mobile phase consisting of (methanol: water; 95:5, v/v) and fluorescence detection (λEx and λEm set at 280 and 340 nm, respectively) was used. The dynamic range was between 0.100 to 10 mg L -1 with relative standard deviation less than 0.45%, (n=4). Limits of detection and recoveries for carbendazim and chlorpyrifos were 0.073 mg L -1 (84.2-106.5%) and 0.062 mg L -1 (85.7-90.3%), respectively. The results revealed that the concentrations of carbendazim and chlorpyrifos residue in all collected samples were below than the EU legal limit.

The radical scavenging activity of phenolic compounds such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as antioxidants, and octyl methylcinnamat (OMC) as UVB-filter in selected personal care products such as sunscreen cream, milk lotion, hair oil and hair gel were evaluated. 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical was used as reagent and antioxidant activity expressed as decrease in the percentage of DPPH. The antibacterial activities of BHA, BHT, OMC and mixture were assessed using two techniques of agar plate diffusion method. The mixture of BHA, BHT and OMC showed the highest percentage of DPPH• inhibition (95.2%), followed by BHA (94.8%), BHT (93.9%) and OMC (9.0%). DPPH• inhibition for crude extracts of selected personal care products were evaluated. The percentage of DPPH• inhibition for sunscreen cream, milk lotion, hair gel and hair oil were 15.3%, 23.5%, 7.7% and 12.7%, respectively. While IC50 of BHA, BHT and mixture were observed at 29.83, 44.16, 32.51 mg/L, respectively. The MIC values for BHA, BHT, OMC and mixture against E. coli using paper-disk diffusion technique were 1.5, 15, 200, 1.5 μg/disk, respectively. While, the MIC values obtained using hole-punch technique were 100, 200, not active, 70 μg/hole for BHA, BHT, OMC and mixture, respectively. In addition, the MIC values obtained by paper-disk diffusion technique for BHA, BHT, OMC, and mixture against S. aureus were 15, 70, not active, 10 μg/disk respectively. On the other hand, MIC values obtained using hole-punch technique were 70, 200, not active, 60 μg/hole for BHA, BHT, OMC and mixture, respectively.