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Marine Fungi-Derived Secondary Metabolites: Potential as Future Drugs for Health Care
Published in Hafiz Ansar Rasul Suleria, Megh R. Goyal, Health Benefits of Secondary Phytocompounds from Plant and Marine Sources, 2021
Syed Shams Ul Hassan, Hui-Zi Jin, Abdur Rauf, Saud Bawazeer, Hafiz Ansar Rasul Suleria
Two spiromeroterpenoids (Chermesins A in image 27 and Chermesins B in image 28 (Figure 8.2)) were evaluated for their antimicrobial activities against human pathogens and aquatic bacteria. Both compounds displayed antimicrobial activity against C. albicans, E. coli and V. alginolyticus. While compounds Chermesins C and Chermesins D did not show any antimicrobial activity because of the absence of double bond at C-5′ or the cyclohexa-2,5 dienone unit, which is essential for antimicrobial efficacy [35].
Metabolic conversion of β-pinene to β-ionone in rats
Published in Xenobiotica, 2021
Lujain Aloum, Mohammad H. Semreen, Taleb H. Al-Tel, Hamza Al-Hroub, Muath Mousa, Richard L. Jayaraj, Eman Alefishat, Abdu Adem, Georg A Petroianu
β-Ionone is a linearly conjugated system (dienone system), which is thermodynamically preferred to be formed in comparison to the α-ionone in which the conjugation is isolated (crossed-conjugated). Thus, it appears that α-ionone is thermodynamically less likely to be formed at physiological temperatures, which could explain the unlikely conversion of β-pinene to α-ionone. Given the low apparent conversion of β-pinene to β-ionone, any α-ionone formed could be present at an even lower amount and most importantly below the limit of detection of this analysis explaining the undetected α-ionone.
In vitro inhibition of food borne mutagens induced mutagenicity by cinnamon (Cinnamomum cassia) bark extract
Published in Drug and Chemical Toxicology, 2018
CEE, CNO, and CLD on simultaneous treatment with various heterocyclic amines showed inconsistent results. While CEE showed antimutagenic activity against almost all the heterocyclic amines, the latter exhibited only marginal or no antimutagenic activity. The antimutagenic activity was mostly observed in the higher doses which may be probably by a direct inhibition of cytochrome P-450-dependant reactions. At the lower doses co-mutagenic activity was observed against certain heterocyclic amines. One of the possible reason for the co-mutagenic activity (enhancement) observed in the lower doses, whereas, antimutagenic activity (inhibition) at the higher dose levels might be due to the fact that, the higher concentrations of S9 with lower concentrations of test chemicals resulted in their conversion into co-mutagens, however, the higher concentrations of the test substance in the presence of the same concentration of S9, results in their antimutagenic activity. It would be desirable to study the comparable antimutagenic activity in S9 and intact hepatocytes to rule out the possibility of intervention by various S9 constituents. Another plausible reason for the co-mutagenicity observed is that during the metabolism of heterocyclic amines in the presence of the test substances (CEE) certain additional free radicals are formed which results in enhancement of the revertant colonies (Holme et al.1983). Wakabayashi et al. (1981) reported co-mutagenic activity of norharman with N-nitrosoamine derivaties only when TA98 strain was used and co-mutagenic activity increased linearly with the increase in the amount of S9. In the present study too, when CEE was tested against AFB1 in TA100 strain, no co-mutagenic activity was observed reconfirming that the co-mutagenic activity (as seen with heterocyclic amines in the present study) is generally observed in TA98 strain only. CLD was not only ineffective in reducing SCE but even increased MMC induced SCE without inducing SCE itself by mechanisms supposed to involve malfunctioning of enzyme activities due to direct chemical interaction of enzyme –SH groups with the conjugated dienone moiety of CLD (Sasaki et al.1989).
Hydroxyl-substituted double Schiff-base condensed 4-piperidone/cyclohexanones as potential anticancer agents with biological evaluation
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2019
Lianshuang Zhang, Qin Chen, Guige Hou, Wei Zhao, Yun Hou
Curcumin (Figure 1), a major active component of the food flavor turmeric, has anti-inflammatory, antibacterial, anticancer and antioxidant activities1. Curcumin and its analogues containing the pharmacophore of 1,5-diaryl-3-oxo-1,4-pentadienyl, are thought to interact at the primary binding site, bio-thiols from susceptible neoplasms. Another pharmacophore of methoxyphenol groups at an auxiliary site also can influence their bio-activities. However, due to its low aqueous solubility, instability and low bioavailability, the clinical utility of curcumin is limited2,3. In recent years, researches have been focused on improving the bioavailability through the structure modification of curcumin4–6. Some 2,6-dibenzylidenecyclohexanone and 3,5-bis(arylidene)-4-piperidone derivatives (BAPs) were synthesized and evaluated bioactivity. These compounds generally possess the 1,5-diaryl-3-oxo-1,4-pentadienyl pharmacophore into their structures to form one or more α,β-unsaturated keto groups, which can react preferentially or exclusively with thiols in contrast to amino and hydroxy groups resulting in a greater chemosensitivity to tumors rather than with normal cells7,8. In addition, two of α,β-unsaturated keto groups enable sequential attacks of cellular thiols to display the better activities9. 3,5-Bis(2-flurobenzylidene)piperidin-4-one (EF24, Figure 1) is a novel curcumin analog, which can inhibit tumor growth and metastasis by inhibiting NF-κB pathways10,11. CLEFMA (Figure 1) can inhibit growth of lung cancer xenografts through inhibiting anti-apoptotic markers (cellular inhibitor of apoptosis protein-1 (cIAP1), Bcl-xL, Bcl-2, and survivin) expression, up-regulating the pro-apoptotic markers Bax and BID expression, and inducing apoptosis by cleavage of caspases 3/9 and PARP12. Curcumin analog (3E,5E)-3,5-bis(3,4,5-trimethoxybenzylidene)-1-methylpiperidin-4-one (L49H37, Figure 1) with fertile electron-donating substitutes exhibits more potent inhibitory effects than curcumin against pancreatic stellate cells (PSCs) cell cycle13. In addition, nitrogen-containing heterocyclic dienones, such as 4-piperidone, can display higher inhibitory properties toward human carcinoma cell lines compared with their homocyclic dienone analogs (such as cyclohexanone)14.