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This study investigated specific properties of chitosan extracted by chemical methods from the micelles of Aspergillus niger grown in tea waste extract. Mixtures prepared from dried tea wastes at 5, 10 and 20% concentrations were sterilized and filtered, then A. niger was inolulated and incubated at 25°C for 5 days. Chitosan was extracted from the biomass by using a chemical method. The results of FT-IR, FESEM, and NMR analyses were used to determine the structural properties of chitosan extracted. In addition, antimicrobial properties of chitosan against Gram positive and Gram negative bacteria, yeasts, and molds were determined by using the disk diffusion test. Results showed that chitosan extraction efficiencies were 13.98, 15.71 and 17.57% for A. niger micelles produced in tea extracts prepared at 5, 10 and 20% concentrations, respectively. It was observed that FT-IR and NMR spectra were compatible with both chitosan from A. niger reported by similar studies and commercial chitosan. It was observed that 1 and 2-4% chitosan solution formed inhibition zones of 7 and 8 mm in diameter against Gram positive and Gram negative bacteria, respectively. Saccharomyces cerevisiae was the most susceptible culture to chitosan. Commercial chitosan showed better antimicrobial activity against the tested microorganisms than fungal chitosan. The deacetylation degree of fungal chitosan was 92%. According to the results of this study, the production of chitosan from A. niger moldgrown in waste teas was carried out for the first time in order to evaluate the waste materials that have gained importance in terms of the environment, and this study could be used as a guide for future studies on this subject. [ABSTRACT FROM AUTHOR]

With the increasing attention of consumers for clean-label foods, the food industry has been in search of natural ingredients as alternatives to synthetic ones. The main factor limiting the shelf life of edible oils is lipid oxidation, and antioxidants are added to foods to prevent this. The resistance of foods to lipid oxidation determines their oxidative stability, which can be measured by accelerated methods at elevated temperatures. In this study, the oxidative stability of widely consumed vegetable edible oils (sunflower, soybean and hazelnut) and the effect of green tea extract as a natural antioxidant were discussed, using exploration of data to ambient temperature by kinetic methods. As a result, the induction period was higher, and the reaction rate constant and Q10 values were lower in the samples with green tea extract (GTE). Moreover, the activation energies of vegetable oils with added GTE were higher. [ABSTRACT FROM AUTHOR]

In this study, concentrated tea extract was obtained from Turkish black tea manufacturing wastes, the amount and composition of cream formed during production and also some properties of the concentrated product were determined. Accordingly, in order to determine the best extraction conditions, the treatments were carried out at three different temperatures (75, 85 and 95 °C), five different time (15, 30, 45, 69 and 90 minutes) and two different waste tea/water feeding ratios (1/15 and 1/20). Extraction experiments showed that the best conditions were 95 ° C for 30 minutes in 1/15 ratio and the water soluble dry matter content of the obtained extract was measured as 1.8 ° Bx, caffeine amount and turbidity value were 0.45 g/100 g and 27.6 NTU, respectively. The highest amount (1.98 g/100 mL) of tea cream formation was observed after 12 hours at 4 °C in the preconcentrated (15°-Bx) extracts, the cream consisted of 15.88% caffeine, 17.08% protein, 8.72% epigallocatechin, 5.89% epigallocatechin gallate, 5.38% catechin gallate, 4.04% epicatechin gallate, 2.83% gallocatechin, 2.15% epicatechin and 1.37% catechin. [ABSTRACT FROM AUTHOR]

Kombucha is a fermented beverage obtained by the fermentation of tea extracts containing sugar by the symbiotic culture of acetic acid bacteria and yeasts. The consumption and studies about the Kombucha are increasing steadily. In this study, caper buds belonging to Capparis ovata Desf. obtained from the Artvin region in Turkey were utilized in Kombucha production; caper buds and Kombucha tea samples (KC1: Green-tea, KC2: Caper bud, KC3: Caper bud + Green-tea) were analyzed. The dry matter, water-soluble dry matter, ash and total acidity and pH of caper buds used in Kombucha tea production were determined as 25.99±1.12 g/100g, 14.47±0.21, 1.74±0.06 g/100g, 0.57±0.06 g/100g and 5.30±0.12, respectively. In Kombucha samples, at the end of fermentation, the total acidity ranged from 0.74±0.02 to 1.43±0.04 g/100g, while the pH was between 3.18±0.01 and 3.19±0.01. Although, caper buds did not contain any anthocyanin, KC1 sample had 2.30 mg/L (cyanidin-3-glycoside equivalent) anthocyanin and it increased by 52% and determined as 3.50 mg/L (cyanidin-3-glycoside equivalent) in KC3 sample by the inclusion of caper buds. In order to determine the potential of Kombucha tea samples on health, antioxidant capacity of samples were determined, and green tea and caper bud containing KC3 sample had the highest values in extractable (TEACABTS: 7.06 μmole Trolox/mL; TEACDPPH: 7.12 μmole Trolox/mL), hydrolyzable (TEACABTS: 7.59 μmole Trolox/mL; TEACCUPRAC: 4.28 μmole Trolox/mL; TEACDPPH: 3.03 μmole Trolox/mL) and bioaccessible phenolics (TEACABTS: 5.70 μmole Trolox/mL; TEACCUPRAC: 4.47 μmole Trolox/mL; TEACDPPH: 2.36 μmole Trolox/mL). In addition, according to sensory evaluation results, KC3 with 5.61 points was the most preferred sample by panelists (overall acceptability). As a result of the study, antioxidant capacity and total phenolic component contents of tea samples were enriched by using a phenolic compond rich substrate capers buds, and a new healthy fermented beverage was produced. [ABSTRACT FROM AUTHOR]

Copyright of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Ürünleri Dergisi is the property of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Urunleri Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Academic Journal of Agriculture / Akademik Ziraat Dergisi is the property of University of Ordu, Faculty of Agriculture, Academic Journal of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Forestry Faculty of Kastamonu University is the property of Kastamonu University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)