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Plant Source Foods
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Carotenoids are present in a variety of fruits and vegetables like carrots, tomatoes, pumpkins, melon, watermelon, paprika, chili pepper, yellow sweet potatoes, mango, microalgae, gac fruit, Brussels sprouts, saffron, and more (22, 24). Carotenoids are sensitive to light and oxidation but relatively stable to heat. Therefore lycopene, a red pigment and strong antioxidant in ripe tomato fruit, is not destroyed by heat; in contrast, its levels may be higher when heating tomatoes. Natural lycopene in fresh ripe tomato is all in trans-isomer form. It is transformed into all cis-isomer form by heating (25). The absorption of cis-lycopene is higher than its natural trans-isomer. Therefore, lycopene bioavailability of processed tomato foods like tomato juice is higher than that in unprocessed fresh tomatoes (25). Intake of processed tomato products is the best way to prevent oxidative stress and carcinogenesis in healthy and Type 2 diabetic patients, as well as prostate cancer patients.
Acne, rosacea, and similar disorders
Published in Rashmi Sarkar, Anupam Das, Sumit Sethi, Concise Dermatology, 2021
The large majority of patients with acne will respond to topical or some combination of topical and systemic drugs. However, some severely affected patients may not, and for them there is another drug that can offer relief. This agent is the cis-isomer of tretinoin – isotretinoin. It reduces sebum secretion by shrinking the sebaceous glands and may also alter keratinization of the mouth of the hair follicle and have an anti-inflammatory action.
Hepatotoxic and Hepatocarcinogenic Effects of Chlorinated Ethylenes*
Published in Robert G. Meeks, Steadman D. Harrison, Richard J. Bull, Hepatotoxicology, 2020
Jeffrey L. Larson, Richard J. Bull
The degree and position of chlorine substitution also is important in affecting sensitivity of the animals to injury, although the pattern of injury remains the same. Hepatic structural derangements are observed in the rat following a 2-h exposure to 1% TCE, in contrast to a 6-h exposure to 5% VC vapor (Reynolds and Moslen, 1977b; Reynolds, 1977). Jenkins et al. (1972) compared the hepatotoxicities of t-DCE, c-DCE, and VDC following oral administration of the compunds to rats. VDC was much more potent in increasing the activities of serum alkaline phosphatase than either of the 1,2-isomers. The cis-isomer was slightly more hepatotoxic than the trans-isomer. This is expected in light of the fact that the rate of c-DCE metabolism is faster than that of t-DCE (Costa, 1983).
The estrogenic activity of resveratrol: a comprehensive review of in vitro and in vivo evidence and the potential for endocrine disruption
Published in Critical Reviews in Toxicology, 2020
Resveratrol (3,5,4′-trihydroxystilbene, MW 228.24 g/mol, Figure 1) is a natural polyphenolic stilbene and common constituent of several edible plants. Two geometric isomers have been purified for resveratrol, the most abundant sterically stable trans-isomer and the cis-isomer. Naturally, both isomers undergo glucosylation to form the glucoside derivatives trans-piceid and cis-piceid, respectively (Romero-Pérez et al. 1999). They also undergo polymerization at low concentrations to form natural oligostilbenes known as viniferins (Korhammer et al. 1995). The biosynthesis of resveratrol and its derivatives is particularly increased following specific physiological and pathological stresses. In addition, regional and cultivar variations influence the levels of resveratrol and its glucosylated and oligomeric products. The level of resveratrol in a variety of food and beverage products has been reported by several studies and ranges from a fraction of a microgram to less than 2 milligrams per product gram or liter (Langcake and Pryce 1976; Siemann and Creasy 1992; Burns et al. 2002; Weiskirchen and Weiskirchen 2016). Generally, the biological actions and therapeutic properties of the trans-isomer dominated most of the scientific literature and are the present focus of this review. However, it is noteworthy that there has been a simultaneous interest in the actions of the cis-isomer- albeit to a lower extent, and a rising interest in the actions of the glucoside and oligomeric derivatives and most recently, the biological metabolites of the trans-isomer.
New sulfonamides containing organometallic-acylhydrazones: synthesis, characterisation and biological evaluation as inhibitors of human carbonic anhydrases
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2019
Yosselin Huentupil, Luis Peña, Néstor Novoa, Emanuela Berrino, Rodrigo Arancibia, Claudiu T. Supuran
Based on 1H NMR data, the organometallic-acylhydrazones (1a–c), (2a–c) and (3a–c) reported in this work exist as a mixture of cis/trans isomers in DMSO-d6 solutions. On this regard, 1H NMR spectra for all compounds show resonances for the CO–NH and CH = N group protons are present in double sets and the signal intensity ratio is ∼0.6 cis: 0.4 trans. This splitting signals pattern was also observed for cyclopentadienyl (C5H5, C5H4) and ethyl (–CH2CH2–) protons. The cis isomer predominates because of a hindered rotation around the CO–NH bond19. Similar results have been reported for organic-acylhydrazones derived from other benzenesulfonamide derivatives37.
Development of LC-MS/MS method and application to bioequivalence study of a light sensitive drug montelukast
Published in Drug Development and Industrial Pharmacy, 2021
Emily Yii Ling Wong, Gabriel Onn Kit Loh, Yvonne Tze Fung Tan, Kok Khiang Peh
Montelukast has an enantiomer, cis isomer (montelukast-S-enantiomer), due to the presence of chiral center at the carbon (methane) of the thioether side chain. The presence of cis isomer is undesired as it does not carry any pharmacological effect [29]. The percentage of cis isomer in montelukast sodium active pharmaceutical ingredient is controlled at ˂ 0.15 % and in pharmaceutical dosage forms (oral granules, tablets and chewable tablets) ˂ 0.20 % [30]. Montelukast underwent photodegradation in solution, solid state and plasma [3–5,17,31–34] to montelukast cis isomer in the presence of light. Ochiai et al. [4] conducted plasma sample preparation under UV cut fluorescent lamp or dark red lamp to prevent the photodegradation of montelukast to cis isomer. Montelukast standard solution exposed to light showed degradation to cis isomer, while montelukast standard solution wrapped with aluminum foil was stable [31]. Montelukast dissolved in 70 % methanol was readily converted to cis isomer when exposed to UV light. Furthermore, photodegradation was more dominant when montelukast was in solution than solid state [32]. Roman et al. [33] reported that precaution steps should be taken during sample preparation as montelukast is photosensitive, especially in solution state. Montelukast is readily converted to its cis isomer upon the exposure to low levels of UV radiation. Gu et al. [17] detected cis isomer in processed plasma samples spiked with montelukast working standard solution after exposing to light for 2 h. For light sensitive drug such as montelukast, it is essential to conduct light stability study in human plasma during method development.