Psychoactive Plant Database - Neuroactive Phytochemical Collection

1. J Exp Bot. 2024 Jun 7;75(11):3452-3466. doi: 10.1093/jxb/erae130.

Identification and characterization of two O-methyltransferases involved in 
biosynthesis of methylated 2-(2-phenethyl)chromones in agarwood.

Wu W(1), Yan T(2), Sun X(1), Wilson I(3), Li G(2), Hong Z(4), Shao F(1), Qiu 
D(1).

Author information:
(1)State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree 
Breeding and Cultivation of National Forestry and Grassland Administration, 
Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, 
China.
(2)Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing, 
100091, China.
(3)CSIRO Agriculture and Food, Canberra, ACT, Australia.
(4)Research Institute of Tropical Forestry, Chinese Academy of Forestry, 
Guangzhou, 510520, China.

The 2-(2-phenethyl)chromones (PECs) are the signature constituents responsible 
for the fragrance and pharmacological properties of agarwood. 
O-Methyltransferases (OMTs) are necessary for the biosynthesis of methylated 
PECs, but there is little known about OMTs in Aquilaria sinensis. In this study, 
we identified 29 OMT genes from the A. sinensis genome. Expression analysis 
showed they were differentially expressed in different tissues and responded to 
drill wounding. Comprehensive analysis of the gene expression and methylated PEC 
content revealed that AsOMT2, AsOMT8, AsOMT11, AsOMT16, and AsOMT28 could 
potentially be involved in methylated PECs biosynthesis. In vitro enzyme assays 
and functional analysis in Nicotiana benthamiana demonstrated that AsOMT11 and 
AsOMT16 could methylate 6-hydroxy-2-(2-phenylethyl)chromone to form 
6-methoxy-2-(2-phenylethyl)chromone. A transient overexpression experiment in 
the variety 'Qi-Nan' revealed that AsOMT11 and AsOMT16 could significantly 
promote the accumulation of three major methylated PECs. Our results provide 
candidate genes for the mass production of methylated PECs using synthetic 
biology.

© The Author(s) 2024. Published by Oxford University Press on behalf of the 
Society for Experimental Biology. All rights reserved. For commercial re-use, 
please contact reprints@oup.com for reprints and translation rights for 
reprints. All other permissions can be obtained through our RightsLink service 
via the Permissions link on the article page on our site—for further information 
please contact journals.permissions@oup.com.

DOI: 10.1093/jxb/erae130
PMID: 38497815 [Indexed for MEDLINE]


2. J Anal Toxicol. 2023 Sep 15;47(7):597-605. doi: 10.1093/jat/bkad056.

Assessment of urinary 6-hydroxy-2,4-cyclohexadienyl mercapturic acid as a novel 
biomarker of benzene exposure.

Bowman BA(1), Lewis EV(1), Goldy DW(1), Kim JY(1), Elio DM(1), Blount BC(1), 
Bhandari D(1).

Author information:
(1)Tobacco and Volatiles Branch, Division of Laboratory Sciences, National 
Center for Environmental Health, Centers for Disease Control and Prevention, 
4770 Buford Hwy NE, Atlanta, GA 30341, USA.

Assessing benzene exposure is a public health priority due to its deleterious 
health effects and ubiquitous industrial and environmental sources of exposure. 
Phenyl mercapturic acid (PhMA) is a commonly used urinary biomarker to assess 
benzene exposure. However, recent work has identified significant 
interlaboratory variation in urinary PhMA concentrations related to 
methodological differences. In this study, we present urinary 
6-hydroxy-2,4-cyclohexadienyl mercapturic acid (pre-PhMA), a metabolite that 
undergoes acid-catalyzed dehydration to form PhMA, as a novel and specific 
urinary biomarker for assessing benzene exposure. We developed and validated the 
first quantitative liquid chromatography-tandem mass spectrometry assay for 
measuring urinary concentrations of pre-PhMA. The pH effect on the method of 
ruggedness testing determined that pre-PhMA is stable across the normal human 
urine pH range and that neutral conditions must be maintained throughout 
quantification for robust and accurate measurement of urinary pre-PhMA 
concentrations. The method exhibited below 2 ng/mL sensitivity for pre-PhMA, 
linearity over three orders of magnitude, and precision and accuracy within 10%. 
Urinary pre-PhMA concentrations were assessed in 369 human urine samples. 
Smoking individuals exhibited elevated levels of pre-PhMA compared to 
non-smoking individuals. Furthermore, the relationship between benzene exposure 
and urinary pre-PhMA levels was explored by examining the correlation of 
pre-PhMA with 2-cyanoethyl mercapturic acid, a smoke exposure biomarker. The 
urinary biomarkers exhibited a positive correlation (r = 0.720), indicating that 
pre-PhMA levels increased with benzene exposure. The results of this study 
demonstrate that urinary pre-PhMA is a rugged and effective novel biomarker of 
benzene exposure that can be widely implemented for future biomonitoring 
studies.

Published by Oxford University Press 2023. This work is written by (a) US 
Government employee(s) and is in the public domain in the US.

DOI: 10.1093/jat/bkad056
PMCID: PMC10935563
PMID: 37632692 [Indexed for MEDLINE]


3. BMC Gastroenterol. 2023 Jun 20;23(1):209. doi: 10.1186/s12876-023-02842-z.

The effect of Trolox on the rabbit anal sphincterotomy repair.

Sarveazad A(1)(2), Yari A(3), Imani F(4), Fayyaz F(1), Mokhtare M(1), 
Babaei-Ghazani A(5)(6), Yousefifard M(7), Sarveazad S(1), Assar S(8), Shamseddin 
J(9), Bahardoust M(10).

Author information:
(1)Colorectal Research Center, Iran University of Medical Sciences, Tehran, 
Iran.
(2)Nursing Care Research Center, Iran University of Medical Sciences, Tehran, 
Iran.
(3)Department of Anatomy, Faculty of Medicine, Alborz University of Medical 
Sciences, Karaj, Iran.
(4)Pain Research Center, Department of Anesthesiology and Pain Medicine, Iran 
University of Medical Sciences, Tehran, Iran.
(5)Neuromusculoskeletal Research Center, Department of Physical Medicine and 
Rehabilitation, Iran University of Medical Sciences, Tehran, Iran.
(6)Department of Physical Medicine and Rehabilitation, University of Montreal 
Health Center, Montreal, Canada.
(7)Physiology Research Center, Iran University of Medical Sciences, Tehran, 
Iran.
(8)Department of Anesthesiology, kerman university of medical sciences, kerman, 
Iran.
(9)Infectious and Tropical Diseases Research Center, Hormozgan Health Institute, 
Hormozgan University of Medical Sciences, Bandar Abbas, Shahid Chamran 
Boulevard, Iran. shams.jebreil@gmail.com.
(10)Department of Epidemiology, School of Public Health, Shahid Beheshti 
University of Medical Sciences, Velenjak 7th Floor, Bldg No.2 SBUMS, Arabi Ave, 
Tehran, 19839-63113, Iran. Mnasourbahari93@gmail.com.

INTRODUCTION: Fecal incontinence (FI) is caused by external anal sphincter 
injury. Vitamin E is a potential strategy for anal sphincter muscle repair via 
its antioxidant, anti-inflammatory, anti-fibrotic, and protective properties 
against myocyte loss. Thus, we aimed to evaluate the water-soluble form of 
vitamin E efficacy in repairing anal sphincter muscle defects in rabbits.
METHODS: Twenty-one male rabbits were equally assigned to the intact (without 
any intervention), control (sphincterotomy), and Trolox (sphincterotomy + Trolox 
administration) groups. Ninety days after sphincterotomy, the resting and 
squeeze pressures were evaluated by manometry, and the number of motor units in 
the sphincterotomy site was calculated by electromyography. Also, the amount of 
muscle and collagen in the injury site was investigated by Mallory's trichrome 
staining.
RESULTS: Ninety days after the intervention, the resting and squeeze pressures 
in the intact and Trolox groups were significantly higher than in the control 
group (P = 0.001). Moreover, the total collagen percentage of the sphincterotomy 
site was significantly lower in the Trolox group than in the control group 
(P = 0.002), and the total muscle percentage was significantly higher in the 
Trolox group compared to the control group (P = 0.001). Also, the motor unit 
number was higher in the Trolox group than in the control group (P = 0.001).
CONCLUSION: Trolox administration in the rabbit sphincterotomy model can 
decrease the amount of collagen and increase muscle, leading to improved anal 
sphincter electromyography and manometry results. Therefore, Trolox is a 
potential treatment strategy for FI.

© 2023. The Author(s).

DOI: 10.1186/s12876-023-02842-z
PMCID: PMC10280897
PMID: 37337166 [Indexed for MEDLINE]

Conflict of interest statement: The authors declare that they have no competing 
interests.


4. ACS Omega. 2021 May 24;6(22):14154-14163. doi: 10.1021/acsomega.1c00671. 
eCollection 2021 Jun 8.

Spectroscopic Study of the Basicity of 4,6-Dihydroxypyrimidine Derivatives.

Vu TQ(1), Yudin NV(1), Kushtaev AA(1), Nguyen TX(1), Maltsev SA(1).

Author information:
(1)Chemical Engineering Faculty, Mendeleev University of Chemical Technology, 9 
Miusskaya Square, Moscow 125047, Russia.

The protonation of a number of 4,6-dihydroxypyrimidine derivatives is studied, 
and the features of the electronic spectra of free bases and protonated forms 
are considered. It is shown that the alkyl substituents in position 2 increase 
the basicity of the compound, and the nitro group in position 5 leads to its 
decrease. In an acid medium (0.1-99.5% H2SO4), 4,6-dihydroxypyrimidine, 
6-hydroxy-2-methylpyrimidine-4(3H)-one, and 
6-hydroxy-2-ethylpyrimidine-4(3H)-one have two protonation stages, barbituric 
acid is protonated in three stages, and 
6-hydroxy-2-methyl-5-nitropyrimidine-4(3H)-one and 
6-hydroxy-2-ethyl-5-nitropyrimidine-4(3H)-one form a monocation.

© 2021 The Authors. Published by American Chemical Society.

DOI: 10.1021/acsomega.1c00671
PMCID: PMC8190809
PMID: 34124438

Conflict of interest statement: The authors declare no competing financial 
interest.


5. Phys Chem Chem Phys. 2021 Apr 22;23(15):9096-9108. doi: 10.1039/d1cp00845e.

Prototropic forms of hydroxy derivatives of naphthoic acid within deep eutectic 
solvents.

Khokhar V (1), Pandey S .

Author information:
(1)Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New 
Delhi - 110016, India. sipandey@chemistry.iitd.ac.in.

Deep eutectic solvents (DESs) are not only recognized as benign and inexpensive 
alternatives to ionic liquids, they offer a unique solvation milieu due to the 
varying H-bonding capabilities of their constituents. Proton-transfer involving 
a probe and its prototropic forms strongly depend on the H-bonding nature of the 
solubilizing media. The presence of prototropic forms of three probes, 
1-hydroxy-2-naphthoic acid (1,2-HNA), 3-hydroxy-2-naphthoic acid (3,2-HNA), and 
6-hydroxy-2-naphthoic acid (6,2-HNA) is investigated in two DESs, named 
ChCl:urea and ChCl:glycerol, constituted of H-bond acceptor choline chloride and 
different H-bond donors, urea and glycerol, respectively, in a 1 : 2 mole ratio 
under ambient conditions. While 1,2-HNA and 3,2-HNA exhibit an intramolecular 
H-bonding ability, 6,2-HNA does not. In contrast to common polar solvents, where 
the monoanionic emitting form of 1,2-HNA is also supported along with the 
neutral one, in both the DESs only the neutral emitting form exists. Addition of 
acid to the two DESs, respectively, fail to generate the monocationic form of 
the probe. Addition of a base to ChCl:urea results in the generation of the 
monoanionic form; even a very high strength of the base fails to generate the 
monoanionic emitting form in ChCl:glycerol. Relatively higher H-bond donating 
acidity of ChCl:glycerol results in added hydroxyl getting involved in H-bonding 
with alcohol functionalities of ChCl:glycerol leading to the absence of proton 
extraction to create the monoanionic form of the probe. Only the monoanionic 
emitting form of 3,2-HNA is present in ChCl:urea; in ChCl:glycerol, due to its 
higher H-bond donor acidity, the neutral emitting form is also detected. 
Addition of high strength of acid to ChCl:urea does result in formation of the 
neutral emitting form. Addition of an aqueous base results in the formation of 
the dianionic form of 3,2-HNA in ChCl:urea; however, in ChCl:glycerol, the added 
base fails to convert the neutral form of this probe to the monoanionic form as 
efficiently as that in ChCl:urea. The monoanionic (carboxylate) form of 6,2-HNA 
exits in ChCl:urea, whereas the neutral form is present in ChCl:glycerol due to 
its higher H-bond donating acidity. Addition of an acid can induce a shift in 
prototropic equilibrium towards the neutral form of 6,2-HNA in ChCl:urea; no 
change is observed in the behavior of this probe in ChCl:glycerol as the acid is 
added. Both the DESs support the dianionic form of 6,2-HNA in the presence of 
the base; the added base helps extract both -OH and -COOH protons of this probe. 
The H-bond donor component of the DES is clearly established to play a critical 
role in the prototropic behavior of the probe.

DOI: 10.1039/d1cp00845e
PMID: 33885096