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Introduction to Waterborne Polyurethanes
Published in Ram K. Gupta, Ajay Kumar Mishra, Eco-Friendly Waterborne Polyurethanes, 2022
Felipe M. de Souza, Prashant Kote, Ram K. Gupta
The biomedical field often requires devices designed to transport and store body fluids, such as whole blood, plasma, and fibrinogen, without adsorbing these biological components into its surface to avoid thrombogenicity, microbial growth, and fouling. Also, biocompatibility, biodegradability, and flexibility are some of the required properties for the device components to be used as a scaffold, or as a vascular graft. Zwitterionic-based WPUs are polymers that can meet these requirements as zwitterionic units, like phosphorylcholine, carboxybetaine, and sulfobetaine are efficient to mitigate protein adsorption. In that regard, Ye et al. developed a biodegradable and elastic WPU that had high resistance to fibrinogen adsorption and thrombogenicity [24]. The synthesis was performed by using polycaprolactone-diol (PCL-diol) and sulfobetaine-diol (SB-diol), in different proportions to react with diisocyanatobutane. During the synthesis, putrescine was used as a chain extender. The obtained polyurethane was processed into fibrous structures to form conduits through the electrospinning process.
Biodegradation
Published in Volodymyr Ivanov, Environmental Microbiology for Engineers, 2020
The biogenic amines are toxic and are substances with foul odor, especially cadaverine and putrescine, which are produced from amino acids lysine and ornitine: H2N–R–CH(NH2)–COOH→H2N–R–CH2NH2+CO2
Role of exogenously applied putrescine in amelioration of cadmium stress in Coriandrum sativum by modulating antioxidant system
Published in International Journal of Phytoremediation, 2022
Rehana Sardar, Shakil Ahmed, Nasim Ahmad Yasin
Polyamines (PAs) are minute poly-cations including putrescine (Put), spermine (Spm) and spermidine (Spd). Such light-weighted biomolecules participates in the maintenance of plant growth and physiochemical events; they also play important roles in modulating physiochemical activities of plants to endure multiple abiotic stresses (Huo et al. 2020). The crosstalk between PAs and cell constituents results in the osmotic regulation in cells (Masson et al. 2017). Methionine generates ammonia propyl which induces the production of Put required for the synthesis pathway of Spm and Spd (Slocum et al. 1984). Xiong et al. (2018) reported the involvement of Put in the improvement of enzymatic antioxidants and enhanced photosynthesis in case of salt stressed tea seedlings. The increased biosynthesis of indigenous PAs scavenges ROS and alleviates abiotic stress in assisted plants (Huo et al. 2020). Similarly, the exogenously applied Put increased the activity of antioxidative enzymes to assuage salinity stress in plants Khan et al. (2012). Due to the involvement of PAs in the alleviation of various abiotic stresses, it was speculated that seed priming with Put may improve the stress tolerance and growth of coriander plants growing in Cd spiked soil.
Impact of exogenous nicotine on the morphological, physio-biochemical, and anatomical characteristics in Capsicum annuum
Published in International Journal of Phytoremediation, 2022
Rami Alkhatib, Batool Alkhatib, Nour Abdo
Nicotine is synthesized from the polyamine putrescine, directly from ornithine, catalyzed by ornithine decarboxylase, or indirectly from arginine catalyzed by arginine decarboxylase. Nicotine is synthesized in the roots and then transported to the shoot by the xylem (Selmar, Engelhardt, et al. 2015). Moreover, Jasmonic acid at the root zone plays a crucial role in regulating the gene expression as well as in stimulating synthesis of the enzymes required for nicotine biosynthesis (Shoji et al.2008; Zhang et al. 2012; Afrin et al. 2015). In addition to nicotine synthesis endogenously, there are generally three nicotine sources for contamination of plant, such as contaminations by smokers (smoke of cigarettes/nicotine residues at the fingers of harvesters) and nicotine which is taken up from the soil (e.g. resulting from butts of cigarettes thrown away).
Novel approach using activated cellulose film for efficient immobilization of purified diamine oxidase to enhance enzyme performance and stability
Published in Preparative Biochemistry & Biotechnology, 2020
Neelam Verma, Lovely Sisodiya, Anjum Gahlaut, Vinita Hooda, Vikas Hooda
Biogenic amines (BAs), mainly formed by decarboxylation of low molecular weight nitrogenous compounds, are ubiquitous in nature. These are known for various roles in many physiological processes such as signal transmission, cell viability, growth and development, act as a fundamental metabolite and an antioxidant in plants and animals when present in appropriate amount. The concentration of BAs is an important aspect of their usefulness or toxicity because their deficiency as well as excess may be lethal for the organism. Diamines (such as putrescine, spermidine, cadaverine, etc.) are foul-smelling compounds that are responsible for the foul odor of putrefying flesh, in processed food and meat products. Rise in their levels is significant remark for cancer (high putrescine), tumors, injuries, or other infection in the body. These are the “markers of freshness or spoilage” for food products, fruits and vegetables especially for processed foods. Therefore, it is essential to detect their concentration in different samples of blood, tissues, and foods to avoid any health-related risk and early diagnosis of cancer. DAO is used for the detection of concentrations of several diamines and polyamines.[1,2]