The Experts below are selected from a list of 28179 Experts worldwide ranked by ideXlab platform
Hong Gao - One of the best experts on this subject based on the ideXlab platform.
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antibacterial effect of 3 p trans coumaroyl 2 hydroxyquinic acid a Phenolic Compound from needles of cedrus deodara on cellular functions of staphylococcus aureus
RSC Advances, 2018Co-Authors: Jinrong Bai, Xiaoyan Liu, Lijin Liu, Kai Zhong, Yina Huang, Hong GaoAbstract:A natural Phenolic Compound, 3-p-trans-coumaroyl-2-hydroxyquinic acid (CHQA) from needles of Cedrus deodara, has been reported to exhibit strong antibacterial activity. In this study, the molecular structural requirements of CHQA for the antibacterial activity and its effect on the cellular functions of Staphylococcus aureus were investigated. The structure–activity relationship analysis revealed that the p-coumaric acid moiety of CHQA was critical for the antibacterial activity, while the esterification between p-coumaric acid and 2-hydroxyquinic acid was unfavorable. Studies of the cellular metabolism demonstrated that CHQA induced a significant decrease in the intracellular ATP concentration but no proportional increase in the extracellular ATP. It was also found that CHQA slightly increased the respiratory activity and succinate dehydrogenase activity of S. aureus. Meanwhile, CHQA decreased the DNA synthesis of S. aureus and directly interacted with DNA through the groove binding mode.
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antibacterial activity and membrane disruptive mechanism of 3 p trans coumaroyl 2 hydroxyquinic acid a novel Phenolic Compound from pine needles of cedrus deodara against staphylococcus aureus
Molecules, 2016Co-Authors: Jinrong Bai, Kai Zhong, Yina Huang, Yan Jiang, Hong GaoAbstract:Recently, we reported that a novel Phenolic Compound isolated from Cedrus deodara, 3-p-trans-coumaroyl-2-hydroxyquinic acid (CHQA), exhibits a potent antioxidant activity. The present study aimed to evaluate the antibacterial activity of CHQA against eleven food-borne pathogens and to elucidate its mechanism of action against Staphylococcus aureus. The results from minimum inhibitory concentration (MIC) determinations showed that CHQA exhibited moderate inhibitory effects on all of the tested pathogens with MIC values ranging from 2.5–10 mg/mL. Membrane potential measurements and flow cytometric analysis demonstrated that CHQA damaged the cytoplasmic membrane of S. aureus, causing a significant membrane hyperpolarization with a loss of membrane integrity. Moreover, CHQA induced an increase in membrane fluidity and conformational changes in membrane protein of S. aureus, suggesting that CHQA probably acts on the cell membrane by interactions with membrane lipid and protein. Transmission electron microscopic observations further confirmed that CHQA disrupted the cell membrane of S. aureus and caused severe morphological changes, which even led to leakage of intracellular constituents. These findings indicated that CHQA could have the potential to serve as a natural antibacterial agent to control and prevent the growth of pathogens in food and in food-processing environments.
Khadija Essafi-benkhadir - One of the best experts on this subject based on the ideXlab platform.
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The Phenolic Compound Kaempferol overcomes 5-fluorouracil resistance in human resistant LS174 colon cancer cells
Scientific Reports, 2019Co-Authors: Ichrak Riahi-chebbi, Soumaya Souid, Houcemeddine Othman, Meriam Haoues, Habib Karoui, Alain Morel, Najet Srairi-abid, Makram Essafi, Khadija Essafi-benkhadirAbstract:Resistance to 5-Fluorouracil chemotherapy is a major cause of therapeutic failure in colon cancer cure. Development of combined therapies constitutes an effective strategy to inhibit cancer cells and prevent the emergence of drug resistance. For this purpose, we investigated the anti-tumoral effect of thirteen Phenolic Compounds, from the Tunisian quince Cydonia oblonga Miller, alone or combined to 5-FU, on the human 5-FU-resistant LS174-R colon cancer cells in comparison to parental cells. Our results showed that only Kaempferol was able to chemo-sensitize 5-FU-resistant LS174-R cells. This Phenolic Compound combined with 5-FU exerted synergistic inhibitory effect on cell viability. This combination enhanced the apoptosis and induced cell cycle arrest of both chemo-resistant and sensitive cells through impacting the expression levels of different cellular effectors. Kaempferol also blocked the production of reactive oxygen species (ROS) and modulated the expression of JAK/STAT3, MAPK, PI3K/AKT and NF-κB. In silico docking analysis suggested that the potent anti-tumoral effect of Kaempferol, compared to its two analogs (Kaempferol 3-O-glucoside and Kampferol 3-O-rutinoside), can be explained by the absence of glucosyl groups. Overall, our data propose Kaempferol as a potential chemotherapeutic agent to be used alone or in combination with 5-FU to overcome colon cancer drug resistance.
Lijuan Liu - One of the best experts on this subject based on the ideXlab platform.
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chemiluminescence of cerium iv rhodamine 6g Phenolic Compound system
Journal of Photochemistry and Photobiology A-chemistry, 2006Co-Authors: Hua Cui, Qunlin Zhang, Aung Myint, Lijuan LiuAbstract:Abstract The oxidation reaction between cerium(IV) and rhodamine 6G in sulfuric acid medium underwent weak chemiluminescence (CL). The effects of 53 organic Compounds of interest on cerium(IV)–rhodamine 6G chemiluminescence were investigated by a flow injection procedure, and 32 Phenolic Compounds were found to enhance CL. Phenolic Compounds mainly include phenols, polyphenols, Phenolic acids, hydroxycinnamic acids and flavonoids. The correlation between CL and molecular structure was systematically studied. It was noteworthy that Phenolic hydroxyls were the main active groups for the generation of CL. The magnitude of CL was related to the type and position of substituents in the benzene ring. The maximal emission wavelength of CL spectra for all tested Phenolic Compounds was at about 555 nm, and luminophors were assigned to rhodamine 6G. Based on the studies of kinetic process and the spectra of CL, fluorescence and UV–vis absorption, a CL mechanism has been proposed to be due to that rhodamine 6G and Phenolic Compound are oxidized by cerium(IV) to form the excited-state cerium(III), which transfers energy to rhodamine 6G, resulting in light emission. However, on the other hand, if the oxidation products of some Phenolic Compounds such as benzoquinone or ketone could significantly quench the emissive rhodamine 6G via energy transfer, no light emission was observed for such Compounds as hydroquinone and catechol.
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sensitive determination of Phenolic Compounds using high performance liquid chromatography with cerium iv rhodamine 6g Phenolic Compound chemiluminescence detection
Journal of Chromatography A, 2005Co-Authors: Qunlin Zhang, Hua Cui, Aung Myint, Mei Lian, Lijuan LiuAbstract:Abstract A simple, selective and sensitive determination method of 20 Phenolic Compounds has been developed using high-performance liquid chromatography (HPLC) with chemiluminescence detection. The method is based on the chemiluminescent enhancement by Phenolic Compound of the cerium(IV)-rhodamine 6G system in sulfuric acid medium. Twenty Phenolic Compounds were separated on a XDB-C 8 column with a gradient elution using a mixture of methanol and 1.0% acetic acid as a mobile phase. Under the optimized conditions, a linear working range extends 2 orders of magnitude with the relative standard deviations of intra- and inter-day precision below 4.0%, and the detection limits (S/N = 3) were in the range of 1.5–82.1 ng/ml. The chemiluminescence reaction was compatible with the mobile phase of high-performance liquid chromatography. The proposed method has been successfully applied to the assay of Phenolic Compounds in red wine without any pretreatment.
Jinrong Bai - One of the best experts on this subject based on the ideXlab platform.
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antibacterial effect of 3 p trans coumaroyl 2 hydroxyquinic acid a Phenolic Compound from needles of cedrus deodara on cellular functions of staphylococcus aureus
RSC Advances, 2018Co-Authors: Jinrong Bai, Xiaoyan Liu, Lijin Liu, Kai Zhong, Yina Huang, Hong GaoAbstract:A natural Phenolic Compound, 3-p-trans-coumaroyl-2-hydroxyquinic acid (CHQA) from needles of Cedrus deodara, has been reported to exhibit strong antibacterial activity. In this study, the molecular structural requirements of CHQA for the antibacterial activity and its effect on the cellular functions of Staphylococcus aureus were investigated. The structure–activity relationship analysis revealed that the p-coumaric acid moiety of CHQA was critical for the antibacterial activity, while the esterification between p-coumaric acid and 2-hydroxyquinic acid was unfavorable. Studies of the cellular metabolism demonstrated that CHQA induced a significant decrease in the intracellular ATP concentration but no proportional increase in the extracellular ATP. It was also found that CHQA slightly increased the respiratory activity and succinate dehydrogenase activity of S. aureus. Meanwhile, CHQA decreased the DNA synthesis of S. aureus and directly interacted with DNA through the groove binding mode.
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antibacterial activity and membrane disruptive mechanism of 3 p trans coumaroyl 2 hydroxyquinic acid a novel Phenolic Compound from pine needles of cedrus deodara against staphylococcus aureus
Molecules, 2016Co-Authors: Jinrong Bai, Kai Zhong, Yina Huang, Yan Jiang, Hong GaoAbstract:Recently, we reported that a novel Phenolic Compound isolated from Cedrus deodara, 3-p-trans-coumaroyl-2-hydroxyquinic acid (CHQA), exhibits a potent antioxidant activity. The present study aimed to evaluate the antibacterial activity of CHQA against eleven food-borne pathogens and to elucidate its mechanism of action against Staphylococcus aureus. The results from minimum inhibitory concentration (MIC) determinations showed that CHQA exhibited moderate inhibitory effects on all of the tested pathogens with MIC values ranging from 2.5–10 mg/mL. Membrane potential measurements and flow cytometric analysis demonstrated that CHQA damaged the cytoplasmic membrane of S. aureus, causing a significant membrane hyperpolarization with a loss of membrane integrity. Moreover, CHQA induced an increase in membrane fluidity and conformational changes in membrane protein of S. aureus, suggesting that CHQA probably acts on the cell membrane by interactions with membrane lipid and protein. Transmission electron microscopic observations further confirmed that CHQA disrupted the cell membrane of S. aureus and caused severe morphological changes, which even led to leakage of intracellular constituents. These findings indicated that CHQA could have the potential to serve as a natural antibacterial agent to control and prevent the growth of pathogens in food and in food-processing environments.
Ichrak Riahi-chebbi - One of the best experts on this subject based on the ideXlab platform.
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The Phenolic Compound Kaempferol overcomes 5-fluorouracil resistance in human resistant LS174 colon cancer cells
Scientific Reports, 2019Co-Authors: Ichrak Riahi-chebbi, Soumaya Souid, Houcemeddine Othman, Meriam Haoues, Habib Karoui, Alain Morel, Najet Srairi-abid, Makram Essafi, Khadija Essafi-benkhadirAbstract:Resistance to 5-Fluorouracil chemotherapy is a major cause of therapeutic failure in colon cancer cure. Development of combined therapies constitutes an effective strategy to inhibit cancer cells and prevent the emergence of drug resistance. For this purpose, we investigated the anti-tumoral effect of thirteen Phenolic Compounds, from the Tunisian quince Cydonia oblonga Miller, alone or combined to 5-FU, on the human 5-FU-resistant LS174-R colon cancer cells in comparison to parental cells. Our results showed that only Kaempferol was able to chemo-sensitize 5-FU-resistant LS174-R cells. This Phenolic Compound combined with 5-FU exerted synergistic inhibitory effect on cell viability. This combination enhanced the apoptosis and induced cell cycle arrest of both chemo-resistant and sensitive cells through impacting the expression levels of different cellular effectors. Kaempferol also blocked the production of reactive oxygen species (ROS) and modulated the expression of JAK/STAT3, MAPK, PI3K/AKT and NF-κB. In silico docking analysis suggested that the potent anti-tumoral effect of Kaempferol, compared to its two analogs (Kaempferol 3-O-glucoside and Kampferol 3-O-rutinoside), can be explained by the absence of glucosyl groups. Overall, our data propose Kaempferol as a potential chemotherapeutic agent to be used alone or in combination with 5-FU to overcome colon cancer drug resistance.