ghrp 6 mg br Introduction Natural antioxidants in vegetables
Introduction Natural antioxidants, in vegetables, have gained the attention of both researchers and consumers. Vegetable amaranth (Amaranthus tricolor) is a good source of minerals, vitamins, phenolics, and carotenoids; it also contains betalains, a nitrogen containing group of natural pigments, as well as ghrp 6 mg and fibers (Venskutonis and Kraujalis, 2013, Repo-Carrasco-Valencia et al., 2010). Those secondary metabolites or natural antioxidants are involved in defenses against several diseases like cancer, atherosclerosis, arthritis, cataracts, emphysema, and retinopathy, neuro-degenerative and cardiovascular diseases (Repo-Carrasco-Valencia et al., 2010, Thaipong et al., 2006) The degree of damage by reactive oxygen species (ROS) is highly related to the balance between ROS production and its removal by the antioxidant scavenging system (Azooz, Ismail, & Abou-Elhamd, 2009). On the other hand, it has been reported that the plant cell membrane was more sensitive to rapid damage and leakage under water stress (Azooz et al., 2009). Plants can synthesize some secondary metabolites i. e., α-tocopherol (vitamin E), and polyphenol to protect them against oxidative damage caused by environmental stresses (Blokhina et al., 2003, Romani et al., 2002). These compounds evolve to detoxify reactive oxygen species in plants, but they also show beneficial activity against some human diseases related to oxidative damage and aging (Iwai, 2008). Amaranths are often described as drought tolerant plants (Liu and Stutzel, 2002, Hura et al., 2007). Amaranthus tricolor is a versatile food crop exhibiting high adaptability to new environments, even in the presence of different biotic and abiotic stresses (Rana, Pradheep, Yadav, Verma, & Sharma, 2007). The amount of metabolites in plants might be affected by different factors such as biological, environmental, biochemical, physiological, ecological, and evolutionary processes (Siracusa & Ruberto, 2014). Among these factors, drought stress can highly enhance the concentration of secondary metabolites (Selmar & Kleinwachter, 2013). There are few reports related to the effect of water stress on secondary metabolites of different crops including leafy vegetables. To date, scarce information is available for betalainic food crops under water stress, although β-xanthin and β-cyanin have recently attracted attention for their antioxidant activities (Stagnari, Angelica, & Mychele, 2016). Water stress elevated secondary metabolites such as β-carotene content in Choysum in dry season trial (Hanson, Yang, Chang, Ledesma, & Ledesma, 2011), in perennial herbaceous (Hillova, Takacsova, & Lichtnerova, 2014), ascorbic acid in tomato (Stagnari et al., 2016), TPC, TFC in buckwheat (Siracusa, Gresta, Sperlinga, & Ruberto, 2017), TPC, TFC and antioxidant activity in Achillea species (Gharibi, Tabatabaei, Saeidi, & Goli, 2016). In contrast, water stress reduced the protein content in buckwheat (Siracusa et al., 2017), β-carotene content in Kailaan in dry season trial (Hanson et al., 2011), ascorbic acid, Ca, Fe and Zn content (Hanson et al., 2011). To our knowledge, there is no information about vegetable amaranth (Amaranthus tricolor) in response to soil water stress in terms of proximate, minerals, β-cyanin, β-xanthin, β-carotene, ascorbic acid, TPC, TFC and antioxidant activity. In our previous studies (Sarker et al., 2014, Sarker et al., 2015a, Sarker et al., 2015b, Sarker et al., 2016, Sarker et al., 2017a, Sarker et al., 2017b, Sarker et al., 2018) we selected some genotypes with a high content in antioxidants and high yield potential. Therefore, to fill the lacuna, present investigation aimed to study the selected vegetable amaranth genotypes in response to soil water stress in terms of proximate, minerals, β-cyanin, β-xanthin, β-carotene, ascorbic acid, TPC, TFC, and total antioxidant activity.
Materials and methods
Results and discussion
Conflict of interest