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Abstract
Tea (Camelia sinensis L.) is one of the main beverages known and consumed all around the world. Quality of tea is not only linked to the raw material but also to the processing steps that influence on the biochemical and sensory characteristics of each type of tea. This overview is focused on the differences in the production and composition of the main types of teas present in the market, highlighting not only their chemical and sensory characteristics, but also the importance of this plant from the food science viewpoint related to its several applications.
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Polyphenols from Food and Natural Products: Neuroprotection and Safety. Antioxidants (Basel) 2020; 9:antiox9010061. [PMID: 31936711 PMCID: PMC7022568 DOI: 10.3390/antiox9010061] [Citation(s) in RCA: 129] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 12/31/2019] [Accepted: 01/07/2020] [Indexed: 02/07/2023] Open
Abstract
Polyphenols are naturally occurring micronutrients that are present in many food sources. Besides being potent antioxidants, these molecules may also possess anti-inflammatory properties. Many studies have highlighted their potential role in the prevention and treatment of various pathological conditions connected to oxidative stress and inflammation (e.g., cancer, and cardiovascular and neurodegenerative disorders). Neurodegenerative diseases are globally one of the main causes of death and represent an enormous burden in terms of human suffering, social distress, and economic costs. Recent data expanded on the initial antioxidant-based mechanism of polyphenols’ action by showing that they are also able to modulate several cell-signaling pathways and mediators. The proposed benefits of polyphenols, either as protective/prophylactic substances or as therapeutic molecules, may be achieved by the consumption of a natural polyphenol-enriched diet, by their use as food supplements, or with formulations as pharmaceutical drugs/nutraceuticals. It has also been proved that the health effects of polyphenols depend on the consumed amount and their bioavailability. However, their overconsumption may raise safety concerns due to the accumulation of high levels of these molecules in the organism, particularly if we consider the loose regulatory legislation regarding the commercialization and use of food supplements. This review addresses the main beneficial effects of food polyphenols, and focuses on neuroprotection and the safety issues related to overconsumption.
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Tang GY, Meng X, Gan RY, Zhao CN, Liu Q, Feng YB, Li S, Wei XL, Atanasov AG, Corke H, Li HB. Health Functions and Related Molecular Mechanisms of Tea Components: An Update Review. Int J Mol Sci 2019; 20:E6196. [PMID: 31817990 PMCID: PMC6941079 DOI: 10.3390/ijms20246196] [Citation(s) in RCA: 165] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 12/02/2019] [Accepted: 12/06/2019] [Indexed: 02/07/2023] Open
Abstract
Tea is widely consumed all over the world. Generally, tea is divided into six categories: White, green, yellow, oolong, black, and dark teas, based on the fermentation degree. Tea contains abundant phytochemicals, such as polyphenols, pigments, polysaccharides, alkaloids, free amino acids, and saponins. However, the bioavailability of tea phytochemicals is relatively low. Thus, some novel technologies like nanotechnology have been developed to improve the bioavailability of tea bioactive components and consequently enhance the bioactivity. So far, many studies have demonstrated that tea shows various health functions, such as antioxidant, anti-inflammatory, immuno-regulatory, anticancer, cardiovascular-protective, anti-diabetic, anti-obesity, and hepato-protective effects. Moreover, it is also considered that drinking tea is safe to humans, since reports about the severe adverse effects of tea consumption are rare. In order to provide a better understanding of tea and its health potential, this review summarizes and discusses recent literature on the bioactive components, bioavailability, health functions, and safety issues of tea, with special attention paid to the related molecular mechanisms of tea health functions.
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Affiliation(s)
- Guo-Yi Tang
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China; (G.-Y.T.); (X.M.); (C.-N.Z.); (Q.L.)
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, No. 10 Sassoon Road, Pokfulam, Hong Kong 999077, China; (Y.-B.F.); (S.L.)
| | - Xiao Meng
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China; (G.-Y.T.); (X.M.); (C.-N.Z.); (Q.L.)
| | - Ren-You Gan
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China; (X.-L.W.); (H.C.)
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610213, China
| | - Cai-Ning Zhao
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China; (G.-Y.T.); (X.M.); (C.-N.Z.); (Q.L.)
| | - Qing Liu
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China; (G.-Y.T.); (X.M.); (C.-N.Z.); (Q.L.)
| | - Yi-Bin Feng
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, No. 10 Sassoon Road, Pokfulam, Hong Kong 999077, China; (Y.-B.F.); (S.L.)
| | - Sha Li
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, No. 10 Sassoon Road, Pokfulam, Hong Kong 999077, China; (Y.-B.F.); (S.L.)
| | - Xin-Lin Wei
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China; (X.-L.W.); (H.C.)
| | - Atanas G. Atanasov
- The Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzębiec, 05-552 Magdalenka, Poland;
| | - Harold Corke
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China; (X.-L.W.); (H.C.)
| | - Hua-Bin Li
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China; (G.-Y.T.); (X.M.); (C.-N.Z.); (Q.L.)
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Bedrood Z, Rameshrad M, Hosseinzadeh H. Toxicological effects of Camellia sinensis (green tea): A review. Phytother Res 2018; 32:1163-1180. [PMID: 29575316 DOI: 10.1002/ptr.6063] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Revised: 01/14/2018] [Accepted: 01/26/2018] [Indexed: 12/21/2022]
Abstract
Many scientific articles proved that green tea (GT), Camellia sinensis, has a great potential to manage central nervous system, cardiovascular, and metabolic diseases and treat cancer and inflammatory disorders. However, it is important to consider that "natural" is not always "safe." Some relevant articles reported side effects of GT, detrimental effects on health. The aim of this study is to provide a classified report about the toxicity of GT and its main constituents in acute, subacute, subchronic, and chronic states. Furthermore, it discusses on the cytotoxicity, genotoxicity, mutagenicity, carcinogenicity, and developmental toxicity of GT and its main constituents. The most important side effects have been reported hepatotoxicity and gastrointestinal disorders specially while consumed on an empty stomach. GT and its main components are not major teratogen, mutagen, or carcinogen substances. However, there is limited data in using them during pregnancy, and they should be used with caution in pregnancy, breast-feeding, and susceptible people. Because GT and its main components have a wide variety of drug interactions, consideration should be taken in coadministration of them with narrow therapeutic indexed drugs. Furthermore, they evoke selective cytotoxicity on cancerous cells that could engage them as an adjuvant substance in cancer therapy.
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Affiliation(s)
- Zeinab Bedrood
- Department of Pharmacodynamy and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Maryam Rameshrad
- Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hossein Hosseinzadeh
- Department of Pharmacodynamy and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.,Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
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