Rapid Quantitative Analysis of Ethanol and Prediction of Methanol Content in Traditional Fruit Brandies from Romania, using FTIR Spectroscopy and Chemometrics

Fourier Transform Infrared (FTIR) spectroscopy in combination with chemometrics were applied for the quality control of 26 fruit brandies made by traditional technology in Romania. Firstly, for the identification and quantitative evaluation of methanol and ethanol in such samples, 4 mixtures of methanol and ethanol standard solutions and a spiked sample were fingerprinted in the 1200 - 950 cm-1 FTIR spectral range, identifying specific wavelength of 1020 and 1112 for methanol, 1047 and 1087 for ethanol. Then, the FTIR spectra of all brandy samples in the range 3500 - 750 cm-1 was registered and the methanol and ethanol concentrations were determined according to the previous calibration. By PCA (Principal component analysis) of FTIR areas (1170 -1000 cm-1), the variability and discrimination between samples was possible, discriminating between the biological and geographical origin of brandy samples. Based on peak areas and intensities, it was predicted the concentration of methanol in all samples, using Partial least squares regression (PLS). The correlation between FTIR and the reference method (GC-FID) was well correlated and significant. It was demostrated that FTIR technique offer a good prediction and statistical correlation with GC-FID technique for methanol quantification.

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Antioxidant Compounds, Mineral Content and Antioxidant Activity of Several Tomato Cultivars Grown in Southwestern Romania

Ten indeterminate tomato cultivars differing in fruit shape and typology, grown simultaneously in a greenhouse from Oltenia (Southwestern Romania) and harvested at red ripe stage, were investigated for the contents in ascorbic acid, lycopene, carotene, total phenolics, minerals (K, Na, Ca and Mg) and trace elements (Fe, Cu, Mn, Cr, Zn and B). In addition, their antioxidant activities were determined. Significant differences were found among tomato cultivars in all studied antioxidant compounds, as well as in the antioxidant activity. Ascorbic acid ranged from 91.9 to 329.7 mg kg-1 fw, lycopene ranged from 19.7 to 49.0 mg kg-1 fw, while total phenolic compounds varied between 300.2 and 557.8 mg kg-1 fw. Antioxidant activity ranged from 0.81 mmol Trolox kg-1 fw to 1.74 mmol Trolox kg-1 fw and it was significantly correlated to total phenolics content (r = 0.91; p< 0.05). The cocktail type cultivar Tiger and the cherry type cultivar Belle proved to be the most powerful in antioxidant activity and phenolic compounds while the rectangular plum shaped cultivar Porto recorded the highest average lycopene content. A valuable cultivar proved to be the brownish red Sacher which registered among the highest contents of phenolics, lycopene and ascorbic acid. Mineral and trace elements contents were also significantly affected by cultivars. Values recorded for K, Ca and Mg ranged from 2139.6 to 3056.9 mg kg-1, 137.7 to 325.8 mg kg-1 and 27.3 to 168.7 mg kg-1 respectively.

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Comparison of Antioxidant and Antimicrobial Properties for Ginkgo biloba and Rosemary (Rosmarinus officinalis L.) from Egypt

The widespread use of medicinal plants for health purposes has increased dramatically due to their great importance to the public health. In this study levels of phenolic, flavonoid contents of Ginkgo biloba and Rosmarinus officinalis from Egypt were determined. HPLC was used to identify and quantify the phenolic compounds in selected plants. The plant extracts were evaluated for their antioxidant activities using various antioxidant methodologies, (i) scavenging of free radicals using 2, 2-diphenyl-1-picrylhydrazyl, (ii) metal ion chelating capacity, and (iii) scavenging of superoxide anion radical. The antimicrobial activity of both plants extracts were evaluated against a panel of microorganisms by using agar disc diffusion method. The total phenolic content (75.30 and 98.31 mg/g dry weight in G. biloba and R. officinalis, respectively) was significantly different. Among the identified phenolic compounds, quercetin, kaempferol and caffeic acid were the predominant phenolic compounds in Ginkgo biloba, whereas carnosic acid, rosmarinic acid, narinigen and hispidulin were the predominant phenolic compound in Rosmarinus officinalis leaves. The antioxidant activity increased with the concentration increase. The R. officinalis was more active than G. biloba extract against Gram-negative bacteria. This study reveals that the consumption of these plants would exert several beneficial effects by virtue of their antioxidant and antimicrobial activities.

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