Optimization of extraction conditions of total phenolics, antioxidant activities, and anthocyanin of oregano, thyme, terebinth, and pomegranate

The purpose of this study was to evaluate the total phenolic extracts and antioxidant activity and anthocyanins of varieties of the investigated plants. These plants include oregano, thyme, terebinth, and pomegranate. The optimum extraction conditions including temperature and solvent of the extraction process itself were investigated. Total phenolic and anthocyanin extracts were examined according to Folin-Ciocalteu assay and Rabino and Mancinelli method, respectively. The effect of different extracting solvents and temperatures on extracts of phenolic compounds and anthocyanins were studied. Plant samples were evaluated for their antioxidant chemical activity by 2, 2-diphenyl-1-picrylhydrazl assay, to determine their potential as a source of natural antioxidant. Results showed that all tested plants exhibited appreciable amounts of phenolic compounds. The methanolic extract (60 °C) of sour pomegranate peel contained the highest phenolic extract (4952.4 mg/100 g of dry weight). Terebinth green seed had the lowest phenolic extract (599.4 mg/100 g of dry weight). Anthocyanins ranged between 3.5 (terebinth red seed) and 0.2 mg/100 g of dry material (thyme). Significant effect of different extracting solvents and temperatures on total phenolics and anthocyanin extracts were found. The methanol and 60 °C of extraction conditions found to be the best for extracting phenolic compounds. The distilled water and 60 °C extraction conditions found to be the best for extracting anthocyanin.     

Parametric relationship between hypoid gear teeth and accurate face-milling cutter

The cutter systems of hypoid gear cutting machines contain groups of inside and outside blades. In these cutter systems, the side cutting edges of the blades machine the convex and concave gear teeth while rotating about the cutter rotation axis. The side cutting edges lay on the rake face formed through the blade, rake, and relief angles; hence, the normal cross-section of the cutter swept surface forms hyperboloid gear teeth. Using the accurate geometry of the cutter system, a relationship between the pressure and spiral angles of the gear tooth and the parameters of the cutter system is developed for the FORMAT machining of a hypoid gear. A new parameterization of the gear tooth surfaces is introduced to determine these angles for the accurate gear tooth by the accurate cutter system. A numerical example with different cutter systems and blade parameters is presented, demonstrating the effects of rake and relief angles over the pressure and spiral angles on mean point projections and gear tooth surface. Finally, the change in pressure and spiral angles with respect to the rake and relief angles are plotted, and the results are analyzed. Finally, it is concluded that the pressure and spiral angles are changed up to a few seconds of a degree in the operating area of the tooth with the change in the back and side rake angles. The side relief angle exhibited little or no effect over the geometry of the gear tooth.The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-019-00286-x     

Effect of jam processing and storage on total phenolics, antioxidant activity, and anthocyanins of different fruits

BACKGROUND: Fruits have been widely recognised as an excellent source of bioactive phenolic compounds. The purpose of this study was to evaluate the effect of jam processing of strawberry, cherry, apricot, fig and orange on the total phenolics, antioxidant activity and anthocyanins during 5 months of storage at 25 °C. RESULTS: Fresh strawberry had the highest contents of total phenolics (8503.1 mg GAE kg^?1) followed by cherry, apricot, fig and orange, respectively. Jam processing decreased the total phenolics, antioxidant activity, and anthocyanins of all fruits. Total phenolics of jam during storage decreased only in apricot, fig and orange. Fresh strawberry had the highest antioxidant activity (54.88% inhibition) followed by the other fruits. Antioxidant activity did not change in strawberry during jam storage, while there are reductions in the other fruits were observed. Fresh strawberry had the highest anthocyanins (2323.8 mg cya‐3‐glu kg^?1), followed by cherry and the other fruits, respectively. Results showed only a decrease of anthocyanins and pH in apricot and fig jams during 5 months of storage. CONCLUSION: Despite the reduction of these compounds in jam processing, it is considered a good method to maintain them during 5 months of storage. Copyright © 2011 Society of Chemical Industry     

Total Phenolics,Antioxidant Activities,and Anthocyanins of Different Grape Seed Cultivars Grown in Jordan

The total phenolics, antioxidant activities, anthocyanins, vitamine E, and tert-butylhydroxytoluene (BHT) of different cultivars of grape seed extracts (GSE) grown in Jordan were evaluated. In addition, antioxidant activities of GSE were investigated using olive oil substrate by oxidative stability instrument (OSI). Results of chemical composition showed that Baladi black and Asbani black had the highest amount of fat content 14.52 and 14.22 g /100 g seed, respectively, followed by Baladi green (13.28 g /100 g seed), Ajloni green (12.24 g/100 g seed), and Khudari green (10.92 g/100 g seed), respectively. The total phenolics and anthocyanins of GSE ranged from 4.66 to 5.12 g/100 g extracts and 0.14 to 0.68 g/100 g extracts, respectively. Antioxidant activities of GSE ranged from 66.4 to 81.40%, while vitamin E and BHT were 90.34 and 94.70%, respectively. Antioxidant activity of the extracts using OSI ranged from 3.10 to 41.13 h induction time, while vitamin E and BHT had 16.33 and 17.20 h, respectively. GSE had high amounts of antioxidants and can be used to retard lipid oxidation in a variety of food products.