China
Africa
Explore chapters and articles related to this topic
Natural Carotenoids
Published in Hafiz Ansar Rasul Suleria, Megh R. Goyal, Masood Sadiq Butt, Phytochemicals from Medicinal Plants, 2019
Umair Shabbir, Sana Khalid, Munawar Abbas, Hafiz Ansar Rasul Suleria
Carotenoid availability and their types can be determined by their color, for example, (1) β-carotene and α-carotene are abundantly present in yellow-orange fruits and vegetables; (2) zeinoxanthin and α-cryptoxanthin present in orange fruits, for example, papaya, mandarin, and orange; and (3) lycopene is the main component of tomatoes, grapefruit, and watermelon with bright red color. Lutein (about 45%), β-carotene (about 25-30%), neoxanthin (10-15%), and violaxanthin (10-15%) are present in green leafy vegetables.53 α-Carotene, lutein, antheraxanthin, zeaxanthin, and β-cryptoxanthin are also found in green vegetables in small amounts. Usually, β-carotene is abundantly found in many vegetables and fruits than to α-carotene.
The Xanthophyll Cycle
Published in Ruth G. Alscher, John L. Hess, Antioxidants in Higher Plants, 2017
Barbara Demmig-Adains, William W. Adams
Among the xanthophylls typically found in the leaves of higher plants, only lutein is a derivative of α-carotene (β, ε-carotene). All other major xanthophylls are derived from β-carotene (β,β-carotene); zeaxanthin, antheraxanthin, violaxanthin, and neoxanthin. A portion of the presumed biosynthetic pathway17 of the formation of the xanthophyll cycle components is depicted in Figures 4 and 5. Neoxanthin is not included in this diagram, but it has been suggested that neoxanthin can be formed from violaxanthin (see below). Excess light specifically stimulates the β,β-carotenoid pathway, and leads to the accumulation of large amounts of β-carotene, and, particularly, the components of the xanthophyll cycle, zeaxanthin, antheraxanthin, and violaxanthin.15,16 The xanthophyll cycle appears to be present throughout all families of higher plants.15,16 From indirect evidence, it seems that, among the three xanthophyll cycle components, zeaxanthin is formed first through hydroxylation of β-carotene. Antheraxanthin and violaxanthin are formed subsequently through epoxidation of zeaxanthin. The epoxidation state of the xanthophyll cycle is thereafter regulated by light. It has recently been reported that a mutant of Arabidopsis, unable to form more than trace amounts of violaxanthin, accumulated larger amounts of both β-carotene and zeaxanthin than did the wild type.18,19 This mutant also possessed reduced levels of lutein as a derivative of α-carotene,19 and was therefore enhanced in the β,β-carotenoid pathway, apparently at the expense of the ß,ε-carotenoid pathway. This mutant contained only trace amounts of neo-xanthin as well, a result consistent with a formation of neoxanthin from violaxanthin.18,19
Flavonoid constituents and protective efficacy of Citrus reticulate (Blanco) leaves ethanolic extract on thioacetamide-induced liver injury rats
Published in Biomarkers, 2023
Usama W. Hawas, Mohamed A. El-Ansari, Abeer F. Osman, Asmaa F. Galal, Lamia T. Abou El-Kassem
Furthermore, the leaves have been traditionally used in the treatment of rheumatic pain, high fever, inflammation, ulcer, and tumour and have been reported to effectively inhibit 1 L-1α-inflammatory cytokine (Yesilada et al.1995, Yesilada et al.1997). In particular, Citrus species contain many important phytochemical compounds such as ascorbic and hydroxycinnamic acids (Manthey and Grohmann 2001, Rapisarda et al. 1999), acridone alkaloids (Samuel et al. 2019, Ye et al. 2022), flavonoids; flavones, flavanones, chalcones, and dihydrochalcones (Wu 1987, Han et al. 2010, Montero-Calderon et al. 2019), provitamin A carotenoids (β-cryptoxanthin) as violaxanthin esters (Giuffrida et al. 2010), and apocarotenoids (β-citraurin) (Luan et al. 2020, Rodrigo et al. 2013). These bioactive metabolites reduce the reactive oxygen species (ROS) and inflammatory mediators in the body, thereby decreasing the risk of metabolic syndrome including diabetes, cardiovascular disease, neurodegenerative diseases, and cancer (Saini et al. 2022). In addition, Citrus essential oil is rich in limonin and terpenes (D-limonene and γ-terpinene) (Raspo et al. 2020, Rossi et al. 2020). This oil is considered an economical product due to its flavouring, antioxidant, and antimicrobial properties (Ambrosio et al.2019).
Functional Foods and Nutraceuticals as Dietary Intervention in Chronic Diseases; Novel Perspectives for Health Promotion and Disease Prevention
Published in Journal of Dietary Supplements, 2018
Carotenoids are a widespread group of naturally occurring fat-soluble pigments found in plants and animals (Mortensen, 2006). They belong to the class of bioactive compounds known as isoprenoid polyenes and are classified by the following characteristics: (a) vitamin A precursors that do not pigment such as β-carotene; (b) pigments with partial vitamin A activity such as cryptoxanthin, β-apo-8′-carotenoic acid ethyl ester; (c) non–vitamin A precursors that do not pigment or pigment poorly such as violaxanthin and neoxanthin; and (d) non–vitamin A precursors that pigment such as lutein and zeaxanthin (Omayma and Singab, 2013). Carotenoid is one of the most complex bioactive compounds due to its structure, which bears multiple conjugated double bonds and cyclic end groups, which makes them capable of forming various stereoisomers with different chemical and physical properties (Omayma and Singab, 2013). Reports have revealed that over 700 carotenoids have been identified; however, only 50 can be found in the human diet and are absorbed and metabolized effectively (Grune et al., 2010; Eroglu and Harrison et al., 2013). Examples of these metabolizable carotenoids often made available to the blood include lycopene, xanthin, beta-carotene, alpha-carotene, lutein, zeaxanthin, beta-cryptoxanthin. These carotenoids can also be found in plant foods such as vegetables, tomatoes, and watermelon (Yeum and Russell, 2002; Roodenburg et al., 2000). Epidemiological studies indicate that a high intake of carotenoids is beneficial to human health and is due to their antioxidant activities (Miller et al., 1996)
Separating toxicity and shading in algal growth inhibition tests of nanomaterials and colored substances
Published in Nanotoxicology, 2022
Lars Michael Skjolding, Sara Nørgaard Sørensen, Karen Scharling Dyhr, Rune Hjorth, Louise Schlüter, Camilla Hedberg, Nanna B. Hartmann, Philipp Mayer, Anders Baun
The freshwater green alga Raphidocelis subcapitata belongs to the class Chlorophyceae, which has pigments similar to those found in higher plants, including chlorophylls, α- and β-carotene, lutein, neoxanthin, violaxanthin, antheraxanthin and zeaxanthin (Young 1993). Changes in the cellular composition of the pigments as a function of light intensity were clearly demonstrated in experiments using neutral-density filters (Figure 2(A)). Decreasing light intensity resulted in a decrease in photo-protective pigments such as astaxanthin, antheraxanthin, and zeaxanthin. The decrease in cellular content of astaxanthin, antheraxanthin and zeaxanthin with decreasing light intensity corresponds with their photo-protective function, as described in literature (Dubinsky and Stambler 2009; Niyogi et al. 1997) (Figure 2(A)). Oppositely, the content of the light harvesting pigments chlorophyll a and b, lutein, neoxanthin, and α- and β-carotene generally increased with decreasing light intensity, although for some of these pigments the content level off at the highest shading level, implying a physical limit for the up-regulation mechanism (Figure 2(A)). It should be noted that pigments such as zeaxanthin, violaxanthin and antheraxanthin are structural components of both light harvesting complexes and photo-protective complexes (units for absorption of excess light energy). Thus, direct interpretation of increases or decreases as function of light availability should be done in connection with the regulation of other pigments to avoid misinterpretation. Similar trends of increasing light harvesting pigments as a function of decreasing light has also been found in other species of chlorophytes e.g. Chlorella sp. and Brachiomonas submarina (Schlüter et al. 2000) as well as Sphaerocystis schroeteri, Stichococcus sp., Mougeotia sp. and Botryococcus braunii (Lauridsen et al. 2011).