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Micronutrients
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Selenium (Se) is an essential micro-mineral (metalloid) for human life. Selenium exists as inorganic salts such as sodium selenite or sodium selenate which are often used for the preparation of Se supplements. Selenate is classified as toxic for the organism. In plants and animals, Se often occurs in organic forms such as selenoproteins, selenoenzymes, or amino acids. In humans, Se forms the active site of several antioxidant enzymes including glutathione peroxidase, thioredoxin reductase, iodothyronine deiodinase, formate dehydrogenase, glycine reductase, and so on. It is also present in many selenoproteins, one of which is selenoprotein P. Se is also a component of the amino acids selenomethionine and selenocysteine, in which Se replaces sulfur (S) of methionine and cysteine respectively. Se is required for immune function and for the synthesis of thyroid hormones. At low doses, the health benefits of Se are as an immunomodulator, antioxidant, and anti-carcinogenic. Se also assists enzymes in protecting cell membranes from damage by oxidative stress. During infection, stress, or tissue injury, selenoenzymes can protect cell membranes against the harmful effects of oxidants like hydrogen peroxide (H2O2) or oxygen radicals (3–4, 8, 20–24).
The Role of Oxidative Stress in Neurodegeneration and Protection by Antioxidants
Published in Abhai Kumar, Debasis Bagchi, Antioxidants and Functional Foods for Neurodegenerative Disorders, 2021
Dietary sodium selenite administered for 24 weeks (10 mg, three times daily) has been reported to exert an effect on the pathophysiology of AD patients (Cardoso et al. 2019). Insufficient supply of selenium to antioxidant enzymes in the brain may contribute to AD pathophysiology. Selenium addition on cultured cell has been shown to directly interdict the ROS produced by Aβ through modulating activity of GPx, which is the most abundant selenoprotein in the brain (Xiong et al. 2007). In this clinical study, the supplementation increased the selenium levels in serum and CSF. However, individual variations such as the Mini-Mental Status Examination (MMSE) score, which is one of the tests to check for cognitive impairment, did not find any potential benefits. It is unclear if the result depended on the dose or time of supplementation of dietary selenium.
The Chemical Environment
Published in Vilma R. Hunt, Kathleen Lucas-Wallace, Jeanne M. Manson, Work and the Health of Women, 2020
Vilma R. Hunt, Kathleen Lucas-Wallace, Jeanne M. Manson
A repetitive theme in chapters and papers on laboratory hazards, particularly in relation to chemical contamination, is the level of apathy and indifference toward safety and health.197 Wood and Spencer198 additionally comment that microbiology laboratories are also chemical laboratories where strong chemical carcinogens are in frequent use: naphthylamines for nitrate reduction tests, benzidine for detection of hydrogen peroxide and bacterial cytochromes, β-propiolactone as a sterilant, and ison-icotinic acid hydrazide for the tuberculosis-sensitivity test. Benzidine has been extensively used in a variety of microbiological tests and has been particularly useful for screening large numbers of organisms. Laboratory exposure to aromatic amines has been associated with known cases of bladder cancer. Sodium selenite is commonly used in media for the isolation of salmonellae and is an animal teratogen.199 In dehydrated media it becomes an airborne inhalation hazard.
Biosynthesis of nano selenium in plants
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2023
Jonas Verstegen, Klaus Günther
The seeds were surface sterilised with 10% formalin solution for 10 min and rinsed thoroughly with ultrapure water. For up to 7 days the seeds were germinated on filter paper, moisturised with ultrapure water, and subsequently transferred into a hydroponic system, containing a growth solution with all essential nutrients that was spiked with sodium selenite. The concentration of sodium selenite in the nutritional solution was 5 mg/l, equivalent to a selenium concentration of 28.91 μM/l. For barley and brown mustard the GHE TriPart Series was used as nutritional solution, for the other plants Hoagland Solution at quarter strength was used. Water was added every other day to keep the water level roughly constant. Light was distributed with two 55 W neon tubes and a reflector. The neon tubes emitted a colour temperature of 6500 K. The days where split into a 16-h light and an 8-h darkness period, in which no artificial light was emitted. The light source was placed about 30 cm above the seeds and was powered from 6 am to 10 pm. The plants grew 28 to 42 days. Following the harvesting, shoot and root were separated and rinsed with the root crown being disposed to avoid intermixing.
Antibacterial activity of Blumea axillaris synthesized selenium nanoparticles against multidrug resistant pathogens of aquatic origin
Published in Egyptian Journal of Basic and Applied Sciences, 2022
Jyoti Prakash Dash, Lopamudra Mani, Sukanta Kumar Nayak
The synthesis of the Se NPs was confirmed by a change in color to brick-red. Solutions containing stem and root extracts of B. axillaris plant indicated the synthesis of Se NPs after keeping them on the orbital shaker for a period of 24–36 h. Further three different salt (sodium selenite) concentrations were used, i.e. 0.1 M, 0.01 M, and 0.001 M. Both stem and root extracts of B. axillaris synthesized Se NPs from 0.1 M sodium selenite . On the contrary, salts with 0.01 M as well as 0.001 M had no and/or poor synthesis of Se NPs. In case of 0.001 M sodium selenite, none of the plant parts exhibited synthesis of Se NPs as no significant color change was observed. Similarly at higher concentration of sodium selenite, i.e. 0.1 M, there was a very poor development of color for the root extract indicating very less synthesis of Se NPs. In case of the stem extract the color change was very slow and though the final color became reddish, it was not much prominent.
Protective Effects of Piceatannol against Selenite-Induced Cataract and Oxidative Damage in Rats
Published in Current Eye Research, 2022
Yating Liu, Jinglan Li, Zi Ye, Tianju Ma, Zhaohui Li
The animals(both male and female rat pups) were randomly divided into four groups, consisting of eight rat pups each. Group 1, as the control group, was treated with the same amount of saline, while Groups 2–4 were administered with sodium selenite6 (3.46 mg/kg body weight) subcutaneously into the neck on postpartum day 10 for cataract induction. Sodium selenite (012585, Alfa Aesar, China) was dissolved in sterile saline to a stock concentration of 0.692 mg/mL and stored at 4 °C to be used. Without further treatment, Group 2 served as the control model group, while Groups 3 and 4 had intraperitoneal piceatannol (Figure 1(A)). at doses of 10 mg/kg13 and 20 mg/kg14 once a day from day 8 to day 17, respectively (Figure 1(B)). Piceatannol (S3026, Selleck, USA) was dissolved in dimethyl sulfoxide (DMSO) and then diluted in sterile saline for animal research to a stock concentration of 4 mg/mL and stored at 4°C in the dark to be used. On postpartum day 17, the rat pups were anesthetized with pentobarbital sodium and examined for cataract formation. Then, all animals were euthanized by the overdosed anesthetic. After further analysis, lens samples were quickly isolated and stored at −80 °C following euthanasia.