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Carboxylesterase Inhibitors: Relevance for Pharmaceutical Applications
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Natural protostane triterpenoids, such as protopanaxadiol and protopanaxatriol, exhibit less potency and poor selectivity on CES1, but display strong inhibitory effects on CES2, suggesting that the long alkyl chain at the C-20 site is unbeneficial for CES1 inhibition (Zou et al., 2017). Recently, 22 protostane triterpenoids have been isolated from the rhizome of Alismaorientale (Mai et al., 2015b), five of which, including alismanol B, 25-O-ethylalisol A, alismanol D, alismanol F, and 11-deoxyalisol A, strongly inhibited CES2 with the IC50 values between 2.02 and 8.68 μM (Table 9.7) (Mai et al., 2015b). Alisol G (25-anhydroalisol A) is a major protostane triterpene obtained from dried rhizomes of Alismaorientalis. Following the biotransformation mediated by P. janthinellumAS 3.510, the metabolites of alisol G, including 25S-25,26-epoxy-alisol G, alisol G (23,24)-diol acetonide and 25,26-dihydroxy-alisol G (23,24)-diol acetonide were obtained, which showed significant CES2 inhibitory effects, with the IC50 values of 6.81, 3.38, and 6.33 μM, respectively (Mai et al., 2015a).
Bioengineering Approach on Terpenoids Production
Published in Dijendra Nath Roy, Terpenoids Against Human Diseases, 2019
Triterpenoids form a diverse class of compounds, many of which have pharmaceutical properties. As most of the triterpenoid biosynthetic genes and enzymes await discovery, pathway engineering in microbial hosts has not been very vigorous. The capacity of native ergosterol biosynthesis in S. cerevisiae has an advantage over E. coli for producing triterpenoids because it produces oxidosqualene, the triterpenoid precursor and it also harbours the CPR partner for the complex triterpenoid pathway. However, engineering efforts have been limited so far. A 500% enhanced production of triterpenoid β-amyrin was attained by overexpression of the native genes ERG8, ERG9 and HFA1 in an S. cerevisiae strain expressing a Pisum sativum β-amyrin synthase (Madsen et al. 2011). Two E. coli chassis systems and a Pichia pastoris system were developed for the production of triterpenoid dammarenediol-II, which is the precursor of dammarane-type tetracyclic ginsenosides by reconstituting the 2,3-oxidosqualene-derived triterpenoid pathway and inhibiting the endogenous consumption of 2,3-oxidosqualene. These systems can also potentially be used for other triterpenoids (Li et al. 2016). The heterologous biosynthesis of protopanaxadiol, a dammarane-type triterpenoid was engineered in S. cerevisiae (Zhao et al. 2016). The yields were further enhanced by increasing the ethanol and stress tolerance of the yeast (Zhao et al. 2017). The microbial transformation of bioactive triterpenoids has also been developed to obtain new novel biologically active compounds as reviewed by Shah et al. (2014). Tetraterpenoid carotenoids are natural pigments widely used in nutraceutical industries as natural food colorants and feed supplements due to their pro-vitamin A and antioxidant activity. Several bacterial, yeast and filamentous fungi naturally produce carotenoids. The heterologous production of carotenoids in the non-carotenogenic microbes E. coli and S. cerevisiae was successful a decade ago. Since then engineering efforts have been to optimise a strain for the commercial production of carotenoids like lycopene astaxanthin, zeaxanthin, lutein (da Costa et al. 2017). Many reviews have discussed the approaches taken for microbial production strategies for carotenoid production (Wang et al. 2016; Ma et al. 2016b).
Application of ultrasonics for nanosizing drugs and drug formulations
Published in Journal of Dispersion Science and Technology, 2022
Ioannis Partheniadis, Rumit R. Shah, Ioannis Nikolakakis
Zhang et al.[72] prepared nanocrystalline suspension (NSS) of the ginsenoside 20(S)-protopanaxadiol (PPD) using an anti-solvent method combined with US (Figure 2). Different anti-solvents, stabilizers, and sonication time were tried and their impact on the particle size and polydispersity was evaluated. Meglumine and bovine serum albumin were screened as stabilizers. Particles of the optimal NSS formulation were spherical with mean size 151 nm (PDI 0.11). In vitro tests showed that 92.36% release of drug after 60 minutes from the NSS, 12.51% from the physical mixture, and 9.71% from the PPD powder.
Effects of different drying methods on drying characteristics, microstructure, quality, and energy consumption of Panax Notoginseng roots (Araliaceae)
Published in Drying Technology, 2022
Dalong Jiang, Hongwei Xiao, Zhian Zheng
Panax Notoginseng (Burk.) F. H. Chen (Araliaceae), a traditional Chinese medicinal herb, mainly grows in southwestern China, Burma, and Nepal. In 2016, the total planting area of Panax Notoginseng in Yunnan province, China was 3,000 hm2.[1]Panax Notoginseng roots have been reported to have antihypertensive, antithrombotic, anti-atherosclerotic, and neuroprotective activities.[2,3] The dried roots of Panax Notoginseng have been classified as a healthy promoting dietary supplement.[4] Over 200 chemical constituents were isolated from Panax Notoginseng, including saponins (PNS), polysaccharides, dencichine, amino acids, flavonoids, phytosterols, cyclopeptides, saccharides, fatty acids, volatile oils, aliphatic acetylene hydrocarbons, and trace elements.[5,6] PNS are the main active compounds of Panax Notoginseng, and more than 100 PNS have been isolated and identified, including ginsenosides, notoginsenosides, and gypenosides. They belong to dammarane-type ginsenoside, which includes two classifications, namely the 20(S)-protopanaxadiol (PDS) and 20(S)-protopanaxatriol (PTS). PNS contain high levels of ginsenoside Rb1, Rd (PDS classification) and ginsenoside Rg1, Re, notoginsenoside R1 (PTS classification). The top five saponins, that is, ginsenoside Rb1, ginsenoside Rg1, notoginsenoside R1, ginsenoside Rd, and ginsenoside Re, are most often used in pharmacy and medicine.[7] Additionally, ginsenoside R1 is an important component of Xueshuantong capsule.[8] The sum of R1, Rg1, Re, Rd, and Rb1 contents is equal to the PNS value. Recently, PNS were shown to have the function of lowering atherosclerosis and thrombosis, preventing myocardial ischemia-reperfusion injury, enhancing cerebral microcirculation and protecting nerve cells.[9]
Effect of pulsed vacuum drying on drying kinetics and quality of roots of Panax notoginseng (Burk.) F. H. Chen (Araliaceae)
Published in Drying Technology, 2021
Dalong Jiang, Hongwei Xiao, Magdalena Zielinska, Guangfei Zhu, Tianyu Bai, Zhian Zheng
Panax notoginseng (Burk.) F. H. Chen (Araliaceae), a traditional Chinese medicinal herb, mainly grows in southwestern China, Burma, and Nepal. In 2016, the total planting area of Panax notoginseng in Yunnan province, China, was 3,000 hm.[1,2]Panax notoginseng roots have been reported to have antihypertensive, antithrombotic, anti-atherosclerotic, and neuroprotective activities.[2,3] The dried roots of Panax notoginseng have been classified as a healthy promoting dietary supplement.[4] Over 200 chemical constituents were isolated from Panax notoginseng, including saponins (PNS), polysaccharides, dencichine, amino acids, flavonoids, phytosterols, cyclopeptides, saccharides, fatty acids, volatile oils, aliphatic acetylene hydrocarbons, and trace elements.[5,6] PNS are the main active compounds of Panax notoginseng, and more than 100 PNS have been isolated and identified, including ginsenosides, notoginsenosides, and gypenosides. They belong to dammarane-type ginsenoside, which includes two classifications, namely the 20(S)-protopanaxadiol (PDS) and 20(S)-protopanaxatriol (PTS). PNS contains high levels of ginsenoside Rb1, Rd (PDS classification) and ginsenoside Rg1, Re, notoginsenoside R1 (PTS classification). The top five saponins, i.e., ginsenoside Rb1, ginsenoside Rg1, notoginsenoside R1, ginsenoside Rd, and ginsenoside Re, are most often used in pharmacy and medicine.[7] Additionally, ginsenoside R1 is an important component of Xueshuantong capsule.[8] The sum of R1, Rg1, Re, Rd, and Rb1 contents is equal to the PNS value. Recently, PNS was shown to have the function of lowering atherosclerosis and thrombosis, preventing myocardial ischemia–reperfusion injury, enhancing cerebral microcirculation and protecting nerve cells.[9]