p-Hydroxy-cinnamic acid

Antimalarial drug interactions of compounds isolated from Kigelia africana (Bignoniaceae) and their synergism with artemether, against the multidrug-resistant W2mef Plasmodium falciparum strain.[Pubmed: 21814840]

Parasitol Res. 2012 Feb;110(2):539-44.

For decades, drug resistance has been the major obstacle in the fight against malaria, and the search for new drugs together with the combination therapy constitutes the major approach in responding to this situation.
METHODS AND RESULTS:
The present study aims at assessing the in vitro antimalarial activity of four compounds isolated from Kigelia africana stem bark (atranorin - KAE1, specicoside - KAE7, 2β,3β,19α-trihydroxy-urs-12-20-en-28-oic acid - KAE3, and p-Hydroxy-cinnamic acid - KAE10) and their drug interactions among themselves and their combination effects with quinine and artemether. The antiplasmodial activity and drug interactions were evaluated against the multidrug-resistant W2mef strain of Plasmodium falciparum using the parasite lactate dehydrogenase assay. Three of the four compounds tested were significantly active against W2mef: specicoside (IC(50) = 1.02 ± 0.17 μM), 2β,3β,19α-trihydroxy-urs-12-en-28-oic acid (IC(50) = 1.86 ± 0.15 μM) and atranorin (IC(50) = 1.78 ± 0.18 μM), whereas p-Hydroxy-cinnamic acid showed a weak activity (IC(50) = 12.89 ± 0.87 μM). A slight synergistic effect was observed between atranorin and 2β,3β,19α-trihydroxy-urs-12-en-28-oic acid (Combination index, CI = 0.82) whereas the interaction between specicoside and p-Hydroxy-cinnamic acid were instead antagonistic (CI = 2.67).
CONCLUSIONS:
All the three compounds showed synergistic effects with artemether, unlike the slight antagonistic interactions of atranorin and 2β,3β,19α-trihydroxy-urs-12-en-28-oic acid in combination with quinine. K. africana compounds are therefore likely to serve as leads in the development of new partner drugs in artemether-based combination therapy.

Thymofolinoates A and B, new cinnamic acid derivatives from Euphorbia thymifolia.[Pubmed: 23157007]

Nat Prod Commun. 2012 Oct;7(10):1351-2.

Two new cinnamic acid derivatives, thymofolinoates A (1) and B (2) have been isolated from the chloroform soluble fraction of Euphorbia thymifolia and their structures assigned from 1H and 13C NMR spectra, DEPT and by 2 D COSY, HMQCand H MBC experiments. In addition, p-Hydroxy-cinnamic acid(3), 5-hydroxy-6,7,8,4'-tetramethoxy flavone (4), and 5-hydroxy-3',4',6,7,8-pentamethoxy flavone (5) have also been isolated for the first time from this species.

Antimicrobial activity of 4-hydroxybenzoic acid and trans 4-hydroxycinnamic acid isolated and identified from rice hull.[Pubmed: 9972252]

Biosci Biotechnol Biochem. 1998 Nov;62(11):2273-6.

METHODS AND RESULTS:
Two antimicrobial substances in rice hull were isolated and identified as 4-hydroxybenzoic acid and trans-4-Hydroxycinnamic acid by LC-MS, and 1H- and 13C-NMR. An evaluation of 50% inhibition of growth (IC50) revealed that the two substances had different inhibition profiles against various microorganisms.
CONCLUSIONS:
Most of the gram-positive and some gram-negative bacteria were sensitive to trans 4-hydroxycinnamic acid and 4-hydroxybenzoic acid at IC50 concentrations of 100-170 and 160 micrograms/ml, respectively.

In vitro evaluation of antioxidant and antibacterial activities of Rotula aquatica and Ancistrocladus heyneanus: Antioxidant and antimicrobial activity of medicinal plants.[Reference: WebLink]

J. Pharm. Res., 2013, 6(2):313-7.

In the present study, the antioxidant and antimicrobial activities of the medicinal plants Rotula aquatica and Ancistrocladus heyneanus were evaluated.
METHODS AND RESULTS:
Antioxidant activity of the plant extracts was determined by total antioxidant capacity, ABTS and DPPH free radical scavenging activity, inhibitory activity toward β-carotene bleaching and lipid peroxidation, and DNA protection activity. Total phenolic and flavonoid contents were also estimated and the major phenolics present in the extract were identified by RP-HPLC. Significant free radical scavenging activity and marked antibacterial activity against food related bacteria Escherichia coli and Salmonella typhi were exhibited by the plant extracts used in the study.
CONCLUSIONS:
The work validates the ethnobotanical usage of the important medicinal plants R. aquatica and A. heyneanus. The plants used in the study possess significant antioxidant and antimicrobial property and have the potential for application in pharmaceutical and food industries as food supplements and natural preservatives.

The bone anabolic carotenoids p-hydroxycinnamic acid and β-cryptoxanthin antagonize NF-κB activation in MC3T3 preosteoblasts.[Pubmed: 21475879]

Mol Med Rep. 2009 Jul-Aug;2(4):641-4.

The carotene p-hydroxycinnamic acid and the xanthophyll β-cryptoxanthin are members of the carotenoid family of plant-derived pigments, which are endowed with anti-osteoporotic properties in vivo. p-Hydroxycinnamic acid and β-cryptoxanthin have been demonstrated to stimulate osteoblastic bone formation while simultaneously repressing osteoclastic bone resorption in vitro. However, their mechanisms of action remain poorly elucidated. It is well established that the NF-;kgr;B signal transduction pathway plays a critical role in osteoclast differentiation. Moreover, we recently demonstrated that NF-κB activity potently antagonizes osteoblastic differentiation and mineralization in vitro.
METHODS AND RESULTS:
In this study, we used transient transfection assays of a NF-κB luciferase reporter to demonstrate that p-hydroxycinnamic acid and β-cryptoxanthin antagonize NF-κB activation in MC3T3 preosteoblastic cells.
CONCLUSIONS:
The data obtained suggest that NF-κB may be a common molecular target by which several bone active agents, including carotenoids, promote osteoblastic bone formation.

Yao Xue Xue Bao. 2014 Aug;49(8):1150-4.

Chemical constituents of lateral roots of Aconitum carmichaelii Debx.[Pubmed: 25322557]

In order to find the cardiotonic constituents of lateral roots of Aconitum carmichaelii Debx., the investigation was carried out.
METHODS AND RESULTS:
Silica gel column chromatography, Sephadex LH-20, medium-pressure MCI and reverse phase ODS column chromatography were used to separate the 90% EtOH extract of the lateral roots of Aconitum carmichaelii Debx. The structures of the isolated compounds have been identified by chemical properties and spectroscopic analyses. Ten compounds were isolated and their structures were elucidated as benzoic acid-5-hydroxy-2-benzoyl-amino methyl ester (1), honokiol (2), pinoresinol (3), salicylic acid (4), p-Hydroxy-cinnamic acid (5), songorine (6), karakoline (7), mesaconitine (8), hypaconitine (9) and 14-benzoylhypaconitine (10), separetely. Compound 1 is a new compound and its structure has been established by NMR, HR-ESI-MS, UV, IR and X-Ray.
CONCLUSIONS:
Compound 2-5 are isolated from the lateral roots of Aconitum carmichaelii Debx. for the first time.