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Benefits of Nanomaterials-Based Biosensors
Published in Jyoti Ranjan Rout, Rout George Kerry, Abinash Dutta, Biotechnological Advances for Microbiology, Molecular Biology, and Nanotechnology, 2022
Sourav Mishra, Rohit Kumar Singh, Uday Suryakanta, Bijayananda Panigrahi, Dindyal Mandal
Another biomolecule, ascorbic acid is antioxidant and plays a vital function in the human body. Cholula diaz et al. reported green synthesized AgNPs by using potato starch (Cholula-Diaz et al., 2018) for detection of ascorbic acid through the SERS technique. The detection depends upon the interaction of AgNPs with specific wavelengths of light, shape, size. The conductance electrons present on the metal surface experience coherent oscillation, resulting in absorption and scattering. The synthesized silver colloids were yellowish in color and which further when characterized by UV-Vis spectroscopy, showed a typical band at 410 nm. Upon incubation with ascorbic acid, the SPR band shifted to 500 nm due to the development of the cluster in the silver nanoparticle when starch is used in relatively higher concentrations during the synthesis (Zhang et al., 2015; McFarland et al., 2005). An intrinsic Raman peak at 1386 cm−1 is seen in starch-capped AgNPs which is due to twisting modes of the starch structure. An enhanced intensity is seen in SERS peak at 1386 cm−1 when the ascorbic acid concentration increases and leads to the reduction of the gap between dimers and trimers in silver nanoparticle clusters which are produced because of ascorbic acid in the colloid due to agglomeration of AgNPs. The limit of detection of ascorbic acid is 0.02 mM, which makes it an appropriate method for the detection of ascorbic acid in a biological specimen (Wei et al., 2007).
Liver
Published in Alan G. Heath, Water Pollution and Fish Physiology, 2018
Ascorbic acid is better known as vitamin C. It plays a number of known biochemical roles and undoubtedly several that are currently unknown. It is essential for the normal synthesis of collagen. Other functions less well studied include involvement in the metabolism of steroids by the liver, oxidation of tyrosine, and in conjunction with superoxide dismutase and catalase, it helps prevent the buildup of free radicals in cells (Lehninger, 1979). Ascorbic acid is discussed here primarily because most of the work in fish has been on liver ascorbic acid, even though it is found in other tissues as well. Species differences are striking; for example, Thomas and Neff (1984) found high levels in the brain of mullet while Lopez-Torres et al. (1993) report that it was non-detectable in the brain of trout.
Structure and Function of Cartilage
Published in Kyriacos A. Athanasiou, Eric M. Darling, Grayson D. DuRaine, Jerry C. Hu, A. Hari Reddi, Articular Cartilage, 2017
Kyriacos A. Athanasiou, Eric M. Darling, Grayson D. DuRaine, Jerry C. Hu, A. Hari Reddi
Fibril collagens represent the most prevalent types of collagen with types I, II, and XI being the predominant members. Fibril collagens have unique nonhelical N- and C-terminal domains per type, but share a characteristic central core of approximately 300 nm in length, comprised of a repeating amino acid sequence G-X-Y, with glycine, proline, and hydroxyproline being the most common constituents (van der Rest and Garrone 1991). This amino acid sequence helps the procollagen monomer exhibit a characteristic left-handed helix structure that can then assemble into a right-handed triple helix in the final trimer. Trimer assembly occurs in the lumen of the endoplasmic reticulum and is mediated by molecular chaperones and the C-propeptides. Hydroxylation of the proline in the Y position is required for the necessary folding and stabilization of the helix through a stereoelectronic effect (Kotch et al. 2008) and is dependent on the presence of ascorbic acid as a cofactor for prolyl-4-hydroxylase to convert proline to hydroxyproline. As primates (and guinea pigs) lack the ability to synthesize ascorbic acid, the lack of dietary ascorbic acid results in the disease state of scurvy. Without ascorbic acid, the hydroxyproline cannot be formed, resulting in procollagen being unable to exit the endoplasmic reticulum, and, thus, the lack of new collagen fibrils being synthesized.
‘A long want’: an archival exploration of scurvy in the Otago goldfields of New Zealand
Published in Journal of the Royal Society of New Zealand, 2023
Hallie R. Buckley, Melandri Vlok, Peter Petchey, Neville Ritchie
Scurvy is a nutritional disease caused by deficiency of Vitamin C (ascorbic acid). Vitamin C is not produced in the human body, so we are entirely reliant on dietary intake (Hirschman and Raugi 1999; Keenan et al. 2002; Linster and Van Schaftingen 2007). The vitamin is an essential component of several cellular processes including reversing oxidisation from free radicals which cause disease in the body. Vitamin C is also an important contributor to the synthesis of collagen production, an essential building block of connective tissue (Linster and Van Schaftingen 2007). The consequence of Vitamin C deficiency leads to a breakdown of bodily tissues that rely on collagen for structural stability, including blood vessels, skin, muscular tissue, and bone (Hirschman and Raugi 1999). Increased risk of more severe infectious disease is another consequence (Wintergerst et al. 2006) of relevance to the pre-antibiotic era.
A critical review for hydrogen application in agriculture: Recent advances and perspectives
Published in Critical Reviews in Environmental Science and Technology, 2023
Renyuan Wang, Xijia Yang, Xunfeng Chen, Xia Zhang, Yaowei Chi, Dan Zhang, Shaohua Chu, Pei Zhou
In addition, H2 also affected the nutritional quality of products by adjusting the content of a variety of physiologically active substances, such as anthocyanin, ascorbic acid, etc. Anthocyanin is a kind of photosensitive pigment with high nutritional value. Ultraviolet light is often used to promote its production products by adjusting the content of a variety of physiologically active substances, such as anthocyanin, ascorbic acid, etc. (Christie & Jenkins, 1996; Nguyen et al., 2014). Recent studies have shown that H2 participates in the accumulation of anthocyanins in the hypocotyls of Radish (Raphanus sativus) under UV treatment by regulating redox homeostasis (Su et al., 2014). There is evidence that indicates the calcium signaling pathway may mediate the induction of anthocyanin by H2 (Zhang, Wei, et al., 2018). The regulatory role of hydrogen-rich water in anthocyanin biosynthesis under UV-A was studied by transcriptomics. However, its molecular mechanism is still unclear (Zhang, Su, et al., 2018). Ascorbic acid is a water-soluble vitamin and an essential nutrient for the human body. Existing evidence shows that H2 has a positive regulatory effect on the accumulation of ascorbic acid in soybean (Glycine max L.) buds under UV irradiation. The results of the molecular analysis confirmed that the above regulation was performed by up regulating the biosynthesis of ascorbic acid (Jia et al., 2017).
Seasonal variations of dustfall fluxes and biochemical parameters in the foliage of selected indoor plants in Delhi, India
Published in International Journal of Phytoremediation, 2023
Ankita Katoch, U. C. Kulshrestha
Ascorbic acid is an antioxidant that acts as a strong reducing agent by scavenging free radicals that are capable of causing lipid peroxidation and cell membrane destruction (Smirnoff 1996; Gavali et al.2002). The average concentrations of AA in the leaves of Ficus elastica were 0.78 ± 0.15 and 1.32 ± 0.21 mg/g f.w., in Ficus lyrata were 0.91 ± 0.20 and 1.61 ± 0.32 mg/g f.w., and in Schefflera arboricola were 0.71 ± 0.18 and 1.26 ± 0.26 mg/g f.w. at DH and MH sites, respectively. The AA concentrations were observed to be significantly different for all the indoor plants between DH and MH sites (p < 0.05) and therefore, it was the only studied biochemical parameter showing significant spatial variation as a marker of pollution stress. Figure 4 shows that the AA content increased with increase in dustfall flux on the foliar surfaces of the indoor plants and the increase was more pronounced at MH site as compared to DH site. It was also observed that average concentrations of AA in the leaves were higher in the winter season as compared to summer and monsoon season (Table 3), and similar results have been reported in previous studies (Prajapati and Tripathi 2008; Gupta et al.2016). More accumulation of AA in winter season with increase simultaneous increase in dustfall indicate the ability of plants to adapt toward stress conditions.