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Terpenoids in Treatment of Immunological Disease
Published in Dijendra Nath Roy, Terpenoids Against Human Diseases, 2019
Avik Sarkar, Surajit Bhattacharjee
Terpenoids are made from five-carbon isoprene units (C5H8) and because of this they are also called isoprenoids; they represent a diversified group of small molecules synthesized by plants. The diverse and complex terpenoid molecules are synthesized from the simple isoprenoid molecule with the help of a large family of terpenoid synthases (Bouvier et al., 2005; Keeling and Bohlmann 2006; Tholl 2006). The synthesis of the basic terpenoid ring takes place by the formation of linear prenyl pyrophosphates—geranyl pyrophosphate (GPP), farnesyl pyrophosphate (FPP) and geranyl geranyl pyrophosphates (GGPP)—through the action of three different prenyltransferase enzymes (Figure 6.1). These prenyl pyrophosphates serve as precursors for the synthesis of various terpenoids like monoterpenoids, sesquiterpenoids and diterpenoids. Terpenoid synthases catalyse the formation of the aforementioned terpenoids. On the other hand, synthesis of triterpenoids also occurs by conversion of oxidosqualene to cyclic triterpenoids by oxidosqualene cyclases (Figure 6.1).
Biosynthesis of Natural Products
Published in Ahindra Nag, Greener Synthesis of Organic Compounds, Drugs and Natural Products, 2022
Athar Ata, Samina Naz, Kenneth Friesen
Monoterpenes are volatile compounds and play an important role in the perfume industry [46]. Geranyl pyrophosphate (65) is a biosynthetic precursor of monoterpenes. This undergoes cyclization to afford limonene (83) which on hydroxylation affords trans-isopiperitenol (84). The latter, on oxidation of hydroxyl group, gives isopiperitenone (85) which after the reduction of endocyclic double bond yields cis isopulegone (86). Isomerization of a double bond in 86 affords pulegone (87). The reduction of double a double in 87 produces both enantiomers of menthone (88 and 89) [47]. The biosynthesis scheme of monoterpenes is shown in Figure 16.17.
Microalgae for Pigments and Cosmetics
Published in Sanjeet Mehariya, Shashi Kant Bhatia, Obulisamy Parthiba Karthikeyan, Algal Biorefineries and the Circular Bioeconomy, 2022
Nídia S. Caetano, Priscila S. Corrêa, Wilson G. de Morais Júnior, Gisela M. Oliveira, António A.A. Martins, Teresa M. Mata, Monique Branco-Vieira
The precursors of the carotenoids biosynthesis in microalgae are the metabolites isopentyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP) that are condensed to form the geranyl pyrophosphate (GPP), the first step of the biosynthetic pathway (Kato and Shinomura, 2020). Further reactions culminate in the production of lycopene, which will drive the carotenoid biosynthesis into two branches: the formation of the pigment lutein, and the pigment β-carotene (Figure 5.2). Consequently, these two pigments can be precursors of other carotenoids, depending on the microalgae strain considered and the culture conditions submitted.
Increasing cannabis use and importance as an environmental contaminant mixture and associated risks to exposed biota: A review
Published in Critical Reviews in Environmental Science and Technology, 2022
Emily K. C. Kennedy, Genevieve A. Perono, Dion B. Nemez, Alison C. Holloway, Philippe J. Thomas, Robert Letcher, Chris Marvin, Jorg Stetefeld, Jake Stout, Oliver Peters, Vince Palace, Gregg Tomy
Cannabinoids are prenylated polyketides biosynthesized from the condensation of olivetolic acid and geranyl-pyrophosphate followed by various cyclization reactions (Gagne et al., 2012; Sirikantaramas et al., 2004; Stout et al., 2012; Taura et al., 2007). While ten different subclassifications of cannabinoids currently exist, the most commonly studied are (-)-Δ9-transtetrahydrocannabinol (Δ9-THC) class and cannabidiol (CBD) class (Bonini et al., 2018; Gonçalves et al., 2020). Cannabinoids are the primary psychoactive component of cannabis resin, with Δ9-THC possessing the greatest potency ranging from 5% in marijuana plant to 80% in hashish oil (Booth & Bohlmann, 2019; Vučković et al., 2018). Contrastingly, CBD is a bioactive cannabinoid that lacks the euphoric effects induced by Δ9-THC, serving as an attractive therapeutic chemical that could potentially mediate several pathologies (Amin & Ali, 2019; Friedman et al., 2019). CBD has been reported to have antagonistic activity to the effects induced by Δ9-THC via allosteric or indirect mechanisms that can be tissue- or cell-specific (Friedman et al., 2019). In addition to Δ9-THC and CBD, eight other major types of cannabinoids have been classified. Given their low abundance in the plant and nonuse medically, they will not be discussed in this review.