Background: Corn zein is a predominatly hydrophobic protein, forming films with relatively good water resistance. Tannic acid, especially in its oxidized form, is supposed to cross-link proteins including zein, which may be explored to further enhance the water resistance of zein films. The effects of different contents (0-8 wt%) of unoxidized and oxidized tannic acid (uTA and oTA, respectively) on the properties of zein films at different pH values (4-9) were studied, according to central composite designs.
Results: Increasing tannic acid contents and pH values resulted in decreased water solubility and increased tensile strength and modulus of films. The presence of tannic acid provided the films with a yellowish color and increased opacity. Paired t-tests indicated that oTA films presented higher tensile strength, lower water vapor permeability and lower water solubility than uTA films.
Conclusion: Higher tannic acid contents and pH values resulted in films with better overall physical properties, which might be ascribed to cross-linking, although the films were still not water resistant. The resulting films have potential to be used for food packaging and coating applications. © 2017 Society of Chemical Industry.
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http://dx.doi.org/10.1002/jsfa.8327 | DOI Listing |
Nutrients
December 2024
Faculty of Medicine and Surgery, Catholic University of the Sacred Heart, 00168 Rome, Italy.
Background/objectives: Benign prostatic hyperplasia (BPH) is one of the most common chronic diseases affecting the urinary tract that occurs mainly in men over 40 years of age. Among the natural therapies, proanthocyanidins (PACs), which can treat a wide range of immune-mediated inflammatory diseases (IMIDs), have been shown to play an important role in the treatment of pathologies concerning prostate health. In this regard, the present study aimed to evaluate the different bioactivities of a grape seed extract (GSE), rich in polymeric PACs, and its version processed under alkaline conditions (ATGSE), characterized by a higher content of oligomeric PACs, in an animal model of BPH induced by subcutaneous injection of testosterone (1 mg/mouse).
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January 2025
Tea Research Institute, Chinese Academy of Agricultural Science, Hangzhou 310008, China.
Matcha is a very popular tea food around the world, being widely used in the food, beverage, health food, and cosmetic industries, among others. At present, matcha shade covering methods, matcha superfine powder processing technology, and digital evaluations of matcha flavor quality are receiving research attention. However, research on the differences in flavor and quality characteristics of matcha from the same tea tree variety from different typical regions in China is relatively weak and urgently required.
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December 2024
Department of Electronic Engineering, Institute for Wearable Convergence Electronics, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin 17104, Republic of Korea.
An energy crisis, resulting from rapid population growth and advancements in the Internet of Things, has increased the importance of energy management strategies. Conventionally, energy management is conducted using sensors; however, additional energy is required to maintain sensor operation within these systems. Herein, an all-fiber-based triboelectric nanogenerator with O plasma treatment, graphene oxide/tannic acid solution coating, and hexane/1-octadecanethiol solution coating (AFT-OGH) is fabricated to implement a self-powered sensor, generating a high electrical power density, of 0.
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December 2024
Department of Wood Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia.
This study compared the use of cellulose nanofibrils (CNF) and lignocellulose nanofibrils (LCNF) in different concentrations to reinforce the poly(vinyl alcohol) (PVA) matrix. Both nanofillers significantly improved the elastic modulus and tensile strength of PVA biocomposite films. The optimum concentration of CNF and LCNF was 6% relative to PVA, which improved the tensile strength of the final PVA biocomposite with CNF and LCNF by 53% and 39%, respectively, compared to the neat PVA film.
View Article and Find Full Text PDFPlants (Basel)
January 2025
Department of Science of Physics, Chemistry and Engineering of Faculty of Science and Technology and Institute of Agricultural and Environmental Research and Technology (IITAA), University of Azores, 9500-321 Ponta Delgada, Portugal.
tea has received considerable attention due to its beneficial effects on health, particularly due to its antioxidant properties that are affected by several factors, which have a high influence on the final quality of black tea. The objective of this study was to investigate the biological properties of Azorean black tea from five different zones of tea plantation in order to select specific areas to cultivate tea rich in targeted compounds beneficial to human health. The free radical scavenging activity (FRSA), ferric reducing antioxidant power (FRAP), ferrous ion chelating (FIC) activities, total phenolic content (TPC), total flavonoid content (TFC), and tannins were determined by colorimetric methods, and catechin and theaflavin contents were analyzed by high-pressure liquid chromatography.
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