br Conclusion Pu erh extracts showed a

Conclusion Pu-erh extracts showed a strong protection effect against the hepatic damage by oxidative stress. The protection mechanism of Pu-erh extracts is confirmed in the study via the activation of the hepatic antioxidant system and the reversal of lipid peroxidation. In addition, Pu-erh tea extracts have important effect on regulating alkaline phosphatase inhibitors level by enhancing the glycogen synthesis and the PK activity, and thus prevent people from liver disease. Therefore, Pu-erh tea can be used as a potential healthy drink for prevention and/or treatment of fatty liver disease and many diseases associated with oxidative stress.
Conflict of interest
Acknowledgments The financial supports from the National Natural Science Fund of China (31371773), Tianjin Higher School Educational Projects of Science and Technology Development Fund (20120603) and the Yunnan Tasly Deepure Biological Tea Group Company Limited (20100908) are gratefully acknowledged.
Introduction Most of the oxidative diseases are due to oxidative stress resulting from free radicals [1]. Free radicals such as superoxide anion, hydroxyl radicals and non-radical species such as hydrogen peroxide and singlet oxygen are different varieties of activated oxygen constituting reactive oxygen species (ROS) [2,3]. An active antioxidative defense system is needed to balance the output of free themes. The oxidative damage produced by free radical generation is a critical etiological factor implicated in several chronic human diseases such as diabetes mellitus, cancer, atherosclerosis, arthritis and neurodegenerative diseases and also in the aging procedure. In the discussion of these diseases, antioxidant therapy has made an enormous importance [4]. Nowadays, the metal nanoparticles may act both as reducing agents by plant extracts and stabilizing agents in the synthesis of nanoparticles due to their specific electrical, optical, magnetic, chemical and mechanical properties are currently used in many high technology areas, such as the medical sector for imaging, faster diagnosis, drug delivery, tissue regeneration, cancer therapeutics, bactericidal and fungicidal agents and antioxidants, as well as the development of new therapeutics [5]. The synthesis of AgNPs can be achieved by chemical reduction [6], electrochemical [7], γ ray irradiation [8], UV-radiation therapy [9], photochemical reduction [10], ultrasonic assisted [11], microwave [12], and laser ablation [13,14]. But each method has been argued in the term of cost, scalability, particle size and dispersion. In particular, chemical method of nanoparticle synthesis was commonly used, but concerning about the adverse toxic effect to the environment, researchers were required to develop a green chemistry protocol for nanoparticle synthesis [15]. Nanoparticle synthesis through exploiting the bio resources (bacteria, fungi, yeasts, algae or plants) proves to be very feasible, cost-effective and eco-friendly alternate [16]. Numerous reports on the synthesis of AgNPs using fruit extract as environmentally friendly substitutes to chemical and physical methods. Further, the survey of earlier literatures suggests that fruit extracts from various plants such as Terminalia chebula[17], Banana (Musa sp.) [18], Dillenia indica[19], Solanum lycopersicums[20], Emblica officinalis[21], Carica papaya[22], Crataegus douglasii[23], Garcinia mangostana[24], Averrhoa carambola[25] and Lantana camara[26] are brimming a source for the synthesis of silver nanoparticles as an alternative to the conventional methods. Considering the vast potentiality of plants as sources this work aims to apply a biological green technique for the synthesis of silver nanoparticles as an alternative to conventional methods. In this regard, Nothapodytes nimmoniana (Icacinaceae) is a small tree, naturally distributed in many parts of the Western Ghats. This tree is a rich source of camptothecin, isoquinoline alkaloid which is currently being used for treating colorectal and ovarian cancer [27]. Silver nanoparticles can be prepared with lower amounts of plant based extract and without any additional chemicals/and or physical steps [28]. Therefore, in the present study, we have synthesized silver nanoaprticles using an aqueous fruit extract of N. nimmoniana and evaluated for antioxidant, antimicrobial and anticancer potentials toward biomedical applications.