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Pharmaceutical Applications of Major Marine Nutraceuticals
Published in Se-Kwon Kim, Marine Biochemistry, 2023
P Madan Kumar, R Janani, S Priya, J Naveen, V Baskaran
The chemical name of FUC is (3S,5R,6S,3′S,5′R,6′R)-5,6-Epoxy-3′-ethanoyloxy-3,5′- dihydroxy-6′,7′-didehydro-5,6,7,8,5′,6′-hexahydro-beta,-beta-caroten-8-one with the molecular formula C42H58O6 and a molecular weight of 658.91 (Yan et al., 1999). FUC has a unique chemical structure containing allene bonds, 5, 6-monoepoxide groups and nine conjugated double bonds. The conjugated double-bond system in FUC readily quenches singlet oxygen (1O2), and the electron-rich status of FUC makes it more suitable to react with free radicals. FUC is easily affected by heat, oxygen tension, pH and light. Nevertheless, the unique molecular structure and chirality of FUC are unstable. Because of its chiral structure and the allenic bond, FUC possesses higher antioxidant activity.
Radiolabeled Enzyme Inhibitors
Published in William C. Eckelman, Lelio G. Colombetti, Receptor-Binding Radiotracers, 2019
Suicide inhibitors possess latent reactive groups that are selectively activated by the target enzyme. Once generated, the reactive group covalently binds to the enzyme leading to its irreversible inhibition. The first and best studied example of this approach was Bloch and co-workers’ use of β,γ-acetylenic thioesters to inactivate β-hydroxy decanoyl thioester dehydrase in E. coli.40 As shown in Figure 9, the dehydrase catalyzes the formation of the highly reactive conjugated allenic thioester from the acetylenic precursor. The aliène group then alkylates a histidine residue at the active site. The thioester of 3-decynoic acid, both in vitro and in vivo, completely inactivates the dehydrase at a concentration of 10−5M.
Affinity Modification — Organic Chemistry
Published in Dmitri G. Knorre, Valentin V. Vlassov, Affinity Modification of Biopolymers, 1989
Dmitri G. Knorre, Valentin V. Vlassov
Further rearrangement and hydrolysis result in the formation of ammonia, butyric acid, and a regenerated enzyme. The enzyme is inhibited by the substrate analogue propargly-glycine which contains the acetylenic group and is believed to yield allene upon neighboring carbanion formation.156
A Biscuit Containing Fucoxanthin Prevents Colorectal Carcinogenesis in Mice
Published in Nutrition and Cancer, 2022
Masaru Terasaki, Wataru Murase, Yukino Kamakura, Serina Kawakami, Atsuhito Kubota, Hiroyuki Kojima, Tohru Ohta, Takuji Tanaka, Hayato Maeda, Kazuo Miyashita, Michihiro Mutoh
A highly polar xanthophyll of fucoxanthin (Fx, Figure 1A), a marine non-provitamin A carotenoid, accounts for >10% of the total biological carotenoids (1). Fx binds to Fx-chlorophyll a/c-binding proteins and contributes to photosynthesis and photoprotection in brown algae and microalgae (2). Chemically, Fx exhibits an unusual allenic bond and a 5,6-monoepoxide. This molecule is known to be present in dietary marine algae such as Undaria pinnatifida (Japanese name, wakame) in Asian countries and Himanthalia elongata (Sea spaghetti) in Europe (3), ranging between 0.3 and 18.6 mg Fx/g dry weight. Toxicity studies have revealed that Fx has no side effects in humans and rodents (4,5). Notably, growing evidence has suggested that Fx is a polyfunctional agent that can exert anti-oxidative, anti-inflammatory, anti-obesity, anti-diabetic, anti-hypertensive, anti-cardiovascular diseases, and anti-angiogenesis activities in humans and animal models (6–12). In particular, the anticancer potential of Fx has been well investigated in vivo and in vitro. Administration of Fx suppresses carcinogenesis or cancer development in colorectal cancer (CRC) murine models by attenuating the tumor microenvironment (13,14), inhibiting signaling pathways associated with adhesion, cell cycle, chemokine receptor, interleukin, MAPK, PI3K/AKT, p53, RAS, STAT, TGF-β, and WNT/β-catenin (15), promoting anoikis induction (16,17), and alteration of gut microbiota (18).
Drug discovery through the isolation of natural products from Burkholderia
Published in Expert Opinion on Drug Discovery, 2021
Adam Foxfire, Andrew Riley Buhrow, Ravi S. Orugunty, Leif Smith
Cepacins: In 1984 P. cepacia strain SC 11,783 (eventually reclassified to B. diffusa ATCC 39,356) was isolated from a soil sample in New Jersey. This organism was cultured and found to produce cepacins A and B (Molecular weights 270.29 and 286.29), two closely related antibiotic compounds. Cepacins A (Figure 2(a. b)) (Figure 2(b)), are allene-diyne class of antibiotics and structures of these two compounds were shown to contain conjugated acetylenes and an allene group along with either one or two epoxides and a gamma lactone [47]. These compounds were tested against a variety of microorganisms. Cepacin A displays submicromolar activity against Staphylococci, and high micromolar activity against Streptococci and most Gram-negative microbes. Cepacin B displayed superior effectiveness against every organism cepacin A was effective against, and additionally was effective against several Gram-negative organisms in which cepacin A showed no activity. Both compounds are rather unstable when purified as solvent-free materials but can be stored in solution in darkness at −20°C for extended periods of time without significant loss of purity or activity. Additionally, the LD50’s (in mice) was 30 mg∙kg−1 and 25 mg∙kg−1 for cepacins A and B, respectively [47].
Role of leptin/STAT3 signaling and RIP-kinases in fucoxanthin influences on mice exposed to LPS and gamma radiation
Published in Toxin Reviews, 2023
Mohamed K. Abdel-Rafei, Noura M. Thabet, Ghada El Tawel, Nermeen M. El Bakary, Neama M. El Fatih, Khaled Sh Azab
Fucoxanthin (FX), one of the bioactive compounds of brown seaweeds, is an important brown- or olive green carotenoid isolated from Undaria pinnatifida, Hijikia fusiformis and Sargassum fulvellum brown seaweeds (Urikura et al.2011). It was found that FX has beneficial effects on human health through its antioxidant, anti-inflammatory, cancer prevention, anti-obesity, anti-diabetic, anti-malarial and anti-lipid effects properties, without side effects (Urikura et al.2011, Ma et al.2017, Su et al.2019). These effects are attributed to unique an allenic bond and a 5, 6-monoepoxide moiety in its molecular structure (Ma et al.2017). Thus, it was revealed that FX possesses a prospective value for further pharmaceutical development.