共查询到20条相似文献,搜索用时 46 毫秒
1.
Sushant Singh Abhay Narayan Singh Anil Verma Vikash Kumar Dubey 《Applied biochemistry and biotechnology》2013,171(7):1545-1558
Biodegradable polycaprolactone (PCL) nanosphere encapsulating superoxide dismutase (SOD) and catalase (CAT) were successfully synthesized using double emulsion (w/o/w) solvent evaporation technique. Characterization of the nanosphere using dynamic light scattering, field emission scanning electron microscope, and Fourier transform infrared spectroscopy revealed a spherical-shaped nanosphere in a size range of 812?±?64 nm with moderate protein encapsulation efficiency of 55.42?±?3.7 % and high in vitro protein release. Human skin HaCat cells were used for analyzing antioxidative properties of SOD- and CAT-encapsulated PCL nanospheres. Oxidative stress condition in HaCat cells was optimized with exposure to hydrogen peroxide (H2O2; 1 mM) as external stress factor and verified through reactive oxygen species (ROS) analysis using H2DCFDA dye. PCL nanosphere encapsulating SOD and CAT together indicated better antioxidative defense against H2O2-induced oxidative stress in human skin HaCat cells in comparison to PCL encapsulating either SOD or CAT alone as well as against direct supplement of SOD and CAT protein solution. Increase in HaCat cells SOD and CAT activities after treatment hints toward uptake of PCL nanosphere into the human skin HaCat cells. The result signifies the role of PCL-encapsulating SOD and CAT nanosphere in alleviating oxidative stress. 相似文献
2.
Abraham Alberto Ramírez-Mendoza Mario Alberto Ramírez-Herrera Cesar Ricardo Cortez-lvarez Sendar Daniel Nery-Flores Aldo Rafael Tejeda-Martínez Marina María de Jesús Romero-Prado María Luisa Mendoza-Magaa 《Molecules (Basel, Switzerland)》2022,27(14)
Ozone (O3) is an oxidating tropospheric pollutant. When O3 interacts with biological substrates, reactive oxygen and nitrogen species (RONS) are formed. Severe oxidative damage exhausts the endogenous antioxidant system, which leads to the decreased activity of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD). Curcumin (CUR) is a natural polyphenol with well-documented antioxidant and anti-inflammatory properties. The aim of this work is to evaluate the effects of curcumin on CAT, GPx, and SOD activity and the inhibition of oxidative damage after the acute and chronic exposure to O3. Fifty male Wistar rats were divided into five experimental groups: the intact control, CUR-fed control, exposed-to-O3 control, CUR-fed (preventive), and CUR-fed (therapeutic) groups. These two last groups received a CUR-supplemented diet while exposed to O3. These experiments were performed during acute- and chronic-exposure phases. In the preventive and therapeutic groups, the activity of plasma CAT, GPx, and SOD was increased during both exposure phases, with slight differences; concomitantly, lipid peroxidation and protein carbonylation were inhibited. For this reason, we propose that CUR could be used to enhance the activity of the antioxidant system and to diminish the oxidative damage caused by exposure to O3. 相似文献
3.
Influence of modified atmosphere treatment on post-harvest reactive oxygen metabolism of pomegranate peels 总被引:1,自引:0,他引:1
AbstractModified atmosphere storage can regulate the reactive oxygen metabolism of fruits and vegetables, reduce the accumulation of hazardous free radicals, and mitigate the peroxidation degree of fruit membrane lipids. In this study, different gas matching ratios were adopted for the modified atmosphere treatment of pomegranate fruits. Up to 120 d of storage, compared with the control treatment, the H2O2 and malonaldehyde (MDA) contents in treatment 2 decreased by 8.88% and 18.28%, respectively, when the activities of superoxide dismutase (SOD), catalase (CAT) and ascorbic acid peroxidase (APX) in treatment 2 increased by 21.44%, 117.38% and 114.95%, the ascorbic acid (ASA) and glutathione (GSH) contents in treatment 2 also increased by 116.83% and 50%, these results showed that treatment 2 (6.0% O2, 6.0% CO2) could effectively regulate various indexes of the reactive oxygen metabolism of pomegranate peels, maintain the normal physiological actions of the fruits, and postpone the ripening and senescence of histocytes. Under treatment 4 (10.0% O2, 10.0% CO2), H2O2 contents in the pomegranate peel significantly increased, and the activities of SOD, CAT and APX significantly reduced. ASA and GSH were degraded, the MDA content abruptly increased, the membrane lipid peroxidation accelerated, and the cytomembrane structure was destroyed. 相似文献
4.
Nayely Leyva-Lpez Melissa Peraza-Arias Anaguiven Avalos-Soriano Crisantema Hernndez Cynthia E. Lizrraga-Velzquez J. Basilio Heredia 《Molecules (Basel, Switzerland)》2021,26(20)
Oxidative stress in aquatic organisms might suppress the immune system and propagate infectious diseases. This study aimed to investigate the protective effect of polyphenolic extracts from spent coffee grounds (SCG) against oxidative stress, induced by H2O2, in C. viridis brain cells, through an in vitro model. Hydrophilic extracts from SCG are rich in quinic, ferulic and caffeic acids and showed antioxidant capacity in DPPH, ORAC and FRAP assays. Furthermore, pretreatment of C. viridis brain cells with the polyphenolic extracts from SCG (230 and 460 µg/mL) for 24 h prior to 100 µM H2O2 exposure (1 h) significantly increased antioxidant enzymes activity (superoxide dismutase and catalase) and reduced lipid peroxidation (measured by MDA levels). These results suggest that polyphenols found in SCG extracts exert an antioxidative protective effect against oxidative stress in C. viridis brain cells by stimulating the activity of SOD and CAT. 相似文献
5.
Seung Sik Lee Eun Mi Lee Sung Hyun Hong Sang-Ho Yoo Jae-Young Cho In Chul Lee Byung Yeoup Chung 《Radiation Physics and Chemistry》2012,81(8):1132-1135
Cyanidin-3-O-xylosylrutinoside (cya-3-O-xylrut), a major pigment in Schizandra chinensis Baillon, was effectively removed by gamma irradiation of greater than 2 kGy, whereas quercetin, the most abundant of the flavonoids and has anti-inflammatory and anti-allergic effects, could be generated by degradation of cya-3-O-xylrut. In the present study, we investigated the effect of combination treatment of gamma irradiation and hydrogen peroxide (H2O2) on the formation of quercetin through the degradation of cya-3-O-xylrut. Cya-3-O-xylrut was significantly degraded (~93%) by gamma irradiation at 2 kGy and it was completely removed by a combination treatment (0.2% H2O2 and 2 kGy gamma ray). The formation of quercetin was significantly appeared at 2 kGy of gamma ray, together with disappearance of cya-3-O-xylrut. The quercetin formation by gamma ray is 3.2 μg/ml and combination treatment is 7.7 μg/ml. Therefore, the combination treatment of H2O2 and gamma ray is more effective to convert cya-3-O-xylrut into quercetin than gamma irradiation only. In conclusion, gamma ray combined with H2O2 would be a promising tool for bio-conversion of organic compounds. 相似文献
6.
Superoxide Dismutase Activity of the Naturally Occurring Human Serum Albumin–Copper Complex without Hydroxyl Radical Formation
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Ryunosuke Kato Dr. Matofusa Akiyama Prof. Dr. Hiroyoshi Kawakami Prof. Dr. Teruyuki Komatsu 《化学:亚洲杂志》2014,9(1):83-86
The superoxide radical anion (O2.?) is biologically toxic and contributes to the pathogenesis of various diseases. Here we describe the superoxide dismutase (SOD) activity of human serum albumin (HSA) complexed with a single CuII ion at the N‐terminal end (HSA–Cu complex). The structure of this naturally occurring copper‐coordinated blood serum protein has been characterized by several physicochemical measurements. The O2.? dismutation ability of the HSA–Cu (1:1) complex is almost the same as that of the well‐known SOD mimics, such as MnIII‐tetrakis(N‐methylpyridinium)porphyrin. Interestingly, the HSA–Cu complex does not induce a subsequent Fenton reaction to produce the hydroxyl radical (OH.), which is one of the most harmful reactive oxygen species. 相似文献
7.
Previous research found Potentilla fruticosa leaf extracts (PFE) combined with green tea polyphenols (GTP) showed obvious synergistic effects based on chemical mechanisms. This study further confirmed the synergy of PFE + GTP viewed from bioactivities using the microbial test system (MTS). The MTS antioxidant activity results showed the combination of PFE + GTP exhibited synergistic effect and the ratio 3:1 showed the strongest synergy, which were in accordance with the results in H2O2 production rate. The combination of PFE + GTP promoted CAT and SOD enzyme activity and their gene expression especially at the ratio 3:1. Therefore, the synergism of PFE + GTP may be due to the promotion of CAT and SOD genes expression which enhanced the CAT and SOD enzyme activities. These results confirmed the synergy of PFE + GTP and could provide theoretical basis to produce a compounded tea made of a mixture of leaves from Potentilla species. 相似文献
8.
Qian Wang Zhiliang Gao Kaijie Zhao Peiyu Zhang Qi-Zhi Zhong Qun Yu Shumei Zhai Jiwei Cui 《中国化学快报》2022,33(4):1917-1922
The intrinsic hypoxic tumor microenvironment and limited accumulation of photosensitizers(PSs) result in unsatisfied efficiency of photodynamic therapy(PDT).To enhance the PDT efficiency against solid tumors,a functional oxygen self-supplying and PS-delivering nanosystem is fabricated via the combination of catalase(CAT),chlorin e6(Ce6) and metal-phenolic network(MPN) capsule.It is demonstrated that the CAT encapsulated in the capsules(named CCM capsules) could catalyze the degradation of hydrog... 相似文献
9.
Fan Yang Jie Wang Chunxi Liu Xiaochen Xu Shunan Shan Zhihua Xia Xiaowei Sun 《Journal of solution chemistry》2012,41(6):976-993
The affinities of apigenin, chrysin, daidzein and quercetin for human serum albumin (HSA) were studied in the presence and absence of Pb2+, Ni2+, Zn2+, Mg2+ and Mn2+. The fluorescence intensities of HSA decrease remarkably with increasing concentration of these four flavonoids. Adding apigenin and chrysin resulted in blue-shifts of HSA from ?? em=336 to 332 nm and 330 nm, respectively. However, quercetin showed an obvious red-shift of HSA from ?? em=336 to 347 nm whereas daidzein hardly affected the ?? em of HSA. The ?? em shifts induced by flavonoids in the presence of mental ions were much bigger than those in the absence of these ions. Pb2+, Ni2+, Zn2+, Mg2+ and Mn2+ increased the quenching constants of these four flavonoids for HSA by 19.2?% to 43?%, 47.7?% to 117?%, 23.3?% to 64.4?%, 9.29?% to 42.2?% and 18?% to 55.6?%, respectively. The affinities of apigenin, chrysin, daidzein and quercetin for HSA increased about 9.49?%, 3.63?%, 5.73?% and 2.32?%, respectively, in the presence of Pb2+. Ni2+ improved the affinities of apigenin, chrysin, daidzein and quercetin for HSA by about 4.79?%, 0.85?%, 11.91?% and 10.55?%, respectively. Zn2+ enhanced the affinities of apigenin, chrysin, daidzein and quercetin for HSA by about 1.03?%, 1.34?%, 1.96?% and 13.14?%, respectively. Mg2+ increased the affinities of apigenin, chrysin, daidzein and quercetin for HSA by about 2.03?%, 0.7?%, 1.39?% and 2.07?%, respectively. Mn2+ increased the affinities of apigenin, chrysin, daidzein and quercetin for HSA by about 2.46?%, 6.71?%, 12.3?% and 4.10?%, respectively. 相似文献
10.
Sander Bekeschus Abraham Lin Alexander Fridman Kristian Wende Klaus-Dieter Weltmann Vandana Miller 《Plasma Chemistry and Plasma Processing》2018,38(1):1-12
A comparative study of two plasma sources (floating-electrode dielectric barrier discharge, DBD, Drexel University; atmospheric pressure argon plasma jet, kINPen, INP Greifswald) on cancer cell toxicity was performed. Cell culture protocols, cytotoxicity assays, and procedures for assessment of hydrogen peroxide (H2O2) were standardized between both labs. The inhibitory concentration 50 (IC50) and its corresponding H2O2 deposition was determined for both devices. For the DBD, IC50 and H2O2 generation were largely dependent on the total energy input but not pulsing frequency, treatment time, or total number of cells. DBD cytotoxicity could not be replicated by addition of H2O2 alone and was inhibited by larger amounts of liquid present during the treatment. Jet plasma toxicity depended on peroxide generation as well as total cell number and amount of liquid. Thus, the amount of liquid present during plasma treatment in vitro is key in attenuating short-lived species or other physical effects from plasmas. These in vitro results suggest a role of liquids in or on tissues during plasma treatment in a clinical setting. Additionally, we provide a platform for correlation between different plasma sources for a predefined cellular response. 相似文献
11.
Chrysin, 7-hydroxyflavone, and quercetin were studied for their affinities with human serum albumin (HSA) in the presence and absence of Fe2+ and Co2+. The fluorescence intensities of HSA decrease remarkably with increasing concentration of the tested flavonoids. Chrysin resulted in a blue-shift of the emission line λ em of HSA from 336 to 330 nm whereas quercetin showed an obvious red-shift of λ em from 336 to 347 nm. However, the extents of the λ em shifts induced by flavonoids in the presence of mental ions are much bigger than those of the corresponding systems in the absence of mental ions. Fe2+ and Co2+ increased the quenching constants of the tested flavonoids for HSA by 12.4–48.1 and 15.0–66.7 %, respectively. The affinities of 7-hydroxyflavone, chrysin and quercetin for HSA increased by about 6.42, 7.38 and 0.62 %, respectively, in the presence of Fe2+. Co2+ increased the affinities of 7-hydroxyflavone, chrysin, and quercetin for HSA about 8.43, 7.86 and 11.73 %, respectively. 相似文献
12.
Maria Michela Cesare Francesca Felice Veronica Conti Luca Cerri Ylenia Zambito Marco Romi Giampiero Cai Claudio Cantini Rossella Di Stefano 《Molecules (Basel, Switzerland)》2021,26(14)
Background: Tomato by-products contain a great variety of biologically active substances and represent a significant source of natural antioxidant supplements of the human diet. The aim of the work was to compare the antioxidant properties of a by-product from an ancient Tuscan tomato variety, Rosso di Pitigliano (RED), obtained by growing plants in normal conditions (-Ctr) or in drought stress conditions (-Ds) for their beneficial effects on vascular related dysfunction. Methods: The antioxidant activity and total polyphenol content (TPC) were measured. The identification of bioactive compounds of tomato peel was performed by HPLC. HUVEC were pre-treated with different TPC of RED-Ctr or RED-Ds, then stressed with H2O2. Cell viability, ROS production and CAT, SOD and GPx activities were evaluated. Permeation of antioxidant molecules contained in RED across excised rat intestine was also studied. Results: RED-Ds tomato peel extract possessed higher TPC than compared to RED-Ctr (361.32 ± 7.204 mg vs. 152.46 ± 1.568 mg GAE/100 g fresh weight). All extracts were non-cytotoxic. Two hour pre-treatment with 5 µg GAE/mL from RED-Ctr or RED-Ds showed protection from H2O2-induced oxidative stress and significantly reduced ROS production raising SOD and CAT activity (* p < 0.05 and ** p < 0.005 vs. H2O2, respectively). The permeation of antioxidant molecules contained in RED-Ctr or RED-Ds across excised rat intestine was high with non-significant difference between the two RED types (41.9 ± 9.6% vs. 26.6 ± 7.8%). Conclusions: RED-Ds tomato peel extract represents a good source of bioactive molecules, which protects HUVECs from oxidative stress at low concentration. 相似文献
13.
Lixia Chen Yang Zhang Xinming Zhang Ruijuan Lv Rongtian Sheng Ruimeng Sun Ting Du Yuhan Li Yanfei Qi 《Molecules (Basel, Switzerland)》2022,27(1)
Anticancer treatment is largely affected by the hypoxic tumor microenvironment (TME), which causes the resistance of the tumor to radiotherapy. Combining radiosensitizer compounds and O2 self-enriched moieties is an emerging strategy in hypoxic-tumor treatments. Herein, we engineered GdW10@PDA-CAT (K3Na4H2GdW10O36·2H2O, GdW10, polydopamine, PDA, catalase, CAT) composites as a radiosensitizer for the TME-manipulated enhancement of radiotherapy. In the composites, Gd (Z = 64) and W (Z = 74), as the high Z elements, make X-ray gather in tumor cells, thereby enhancing DNA damage induced by radiation. CAT can convert H2O2 to O2 and H2O to enhance the X-ray effect under hypoxic TME. CAT and PDA modification enhances the biocompatibility of the composites. Our results showed that GdW10@PDA-CAT composites increased the efficiency of radiotherapy in HT29 cells in culture. This polyoxometalates and O2 self-supplement composites provide a promising radiosensitizer for the radiotherapy field. 相似文献
14.
High concentration glucose in diabetes mellitus may stimulate nonenzymatic glycation of proteins. Hemoglobin (Hb) and human serum albumin (HSA) are among the most sensitive proteins for the modification by glucose. In this paper, we report our study of Hb and HSA modification by glucose using electrochemical methods. Compared with native Hb, it is found that highly glycated Hb presents lower electron transfer reactivity and electrocatalytic activity toward O2 and H2O2, and the glycation is glucose concentration and time dependent. Meanwhile, the changes of the electrochemical signal of heme after binding with HSA and glycated HSA have also suggested that proteins modified by high concentration glucose lasting for months and years in diabetes mellitus might be the reason for diabetes mellitus complication. 相似文献
15.
The models of oxidative damage-induced aging were established by adding ethanol (C2H5OH), hydrogen peroxide (H2O2) and 6-hydroxydopamine (6-OHDA) to zebrafish embryos in this research. To find effective protective drugs/foods, Salvianolic acid B (Sal B) was added after the embryos were treated by these oxidative reagents. After being treated with ethanol, H2O2 and 6-OHDA, the morphological changes were obvious and the deformities included spinal curvature, heart bleeding, liver bleeding, yolk sac deformity and pericardial edema, and the expression of oxidative stress-related genes Nrf2b, sod1 and sod2 and aging-related genes myl2a and selenbp1 were significantly up-regulated compared to the control group. While after adding 0.05 μg/mL and 0.5 μg/mL Sal B to the ethanol-treated group, death rates and MDA levels decreased, the activity of antioxidant enzyme (SOD, CAT and GSH-Px) changed and Nrf2b, sod1, sod2, myl2a, selenbp1, p53 and p21 were down-regulated compared to the ethanol-treated group. The bioinformatics analysis also showed that oxidative stress-related factors were associated with a variety of cellular functions and physiological pathways. In conclusion, Sal B can protect against aging through regulating the Keap1/Nrf2 pathway as well as antioxidative genes and enzyme activity. 相似文献
16.
Shokoofeh Hajihashemi Ali Akbar Ehsanpour 《Applied biochemistry and biotechnology》2014,172(8):4038-4052
This investigation was carried out with the aim of determining the effect of paclobutrazol (PBZ) (0 and 2 mg l?1) and polyethylene glycol (PEG) (0, 2, 4 and 6 %?w/v of PEG 6000) treatments on antioxidant system of Stevia rebaudiana Bertoni under in vitro condition. Analysis of data showed that PEG treatment significantly increased hydrogen peroxide (H2O2) and phenolic contents, while PBZ treatment limited the effect of PEG on them. Our data revealed that PEG treatment significantly increased total antioxidant capacity, catalase (CAT), ascorbate peroxidase (APX), polyphenol oxidase (PPO) and peroxidase (POD) activity, while it inversely decreased glutathione reductase (GR) activity. The superoxide dismutase (SOD) activity was not affected by PEG treatment. PBZ treatment induced significantly higher levels of CAT and GR activity and lower levels of SOD activity in PEG-treated plants. PBZ in combination with PEG resulted in no significant difference on APX activity with PEG treatment alone. PBZ treatment prevented the effect of PEG on the PPO activity. PEG (with or without PBZ) treatment increased the ascorbate pool, whereas total glutathione level was not affected by PEG. Our finding indicated that PBZ reduced the negative effect of PEG treatment by quenching H2O2 accumulation and increasing the CAT activity. Collectively, the antioxidant capacity of S. rebaudiana in PEG treatment condition was associated with active enzymatic and non-enzymatic defence systems which partly could be improved by the PBZ treatment. In addition, a higher accumulation of phenolic compounds leads to a more potent reactive oxygen species scavenging activity in S. rebaudiana. 相似文献
17.
R. Cai R. Baba K. Hashimoto Y. Kubota A. Fujishima 《Journal of Electroanalytical Chemistry》1993,360(1-2)
Electron transfer from photoexcited TiO2 particles to dissolve oxygen (O2), and then to an active center of superoxide dismutase (SOD), was investigated by a slurry electrode technique. As a result of electron transfer, the superoxide anion (O2−) was formed initially, and was then further converted effectively into H2O2 by SOD catalysis. At a constant applied potential of 0.6 V (vs. SCE), an increase in photocurrent resulting from oxidation of O2− and H2O2 on a SnO2 working electrode was observed. However, such an increase in photocurrent decreased rapidly on the addition of catalase, which is a scavenger of H2O2. 相似文献
18.
The redox reaction is a normal process of biological metabolism in the body that leads to the production of free radicals. Under conditions such as pathogenic infection, stress, and drug exposure, free radicals can exceed normal levels, causing protein denaturation, DNA damage, and the oxidation of the cell membrane, which, in turn, causes inflammation. Acanthopanax senticosus (A. senticosus) flavonoids are the main bioactive ingredients with antioxidant function. H2O2-treated RAW 264.7 cells and DSS-induced colitis in mice were used to evaluate the antioxidant properties of A. senticosus flavonoids. The results show that A. senticosus flavonoids can significantly downregulate the levels of ROS and MDA in H2O2-treated RAW 264.7 cells and increase the levels of CAT, SOD, and GPx. A. senticosus flavonoids can also increase the body weights of DSS-induced colitis mice, increase the DAI index, and ameliorate the shortening of the colon. ELISA experiments confirmed that A. senticosus flavonoids could reduce the level of MDA in the mouse serum and increase the levels of SOD, CAT, and GPx. Histopathology showed that the tissue pathological changes in the A. senticosus flavonoid group were significantly lower than those in the DSS group. The Western blot experiments showed that the antioxidant capacity of A. senticosus flavonoids was accomplished through the Nrf2 pathway. In conclusion, A. senticosus flavonoids can relieve oxidative stress in vivo and in vitro and protect cells or tissues from oxidative damage. 相似文献
19.
Linyu Li Qunce Huang Shuyin Zhang Shuaipeng Zhao 《Applied biochemistry and biotechnology》2013,171(4):1072-1083
To understand the effect of enhanced UV-B radiation and low-energy N+ ion beam radiation on the response of photosynthesis, antioxidant enzymes, and lipid peroxidation in rice seedlings, Oryza sativa was exposed to three different doses of low-energy N+ ion beam and enhanced UV-B alone and in combination. Enhanced UV-B caused a marked decline in some photosynthetic parameters (net photosynthetic rate, transpiration rate, and stomatal conductance) and photosynthetic pigments, whereas it induced an increase in hydrogen peroxide (H2O2) accumulation, the rate of superoxide radical production, and the content of malondialdehyde (MDA). Enhanced UV-B also induced an increase in the activity of antioxidant enzymes (superoxide dismutase [SOD], peroxidase (POD), and catalase [CAT]) and some nonenzymatic antioxidants such as proline. Under the combined treatment of enhanced UV-B and low-energy N+ ion beam at the dose of 3.0?×?1017 N+ cm?2, the activity of antioxidant compounds (SOD, POD, CAT, proline, and glutathione), photosynthetic pigments, and some photosynthetic parameters (net photosynthetic rate, transpiration rate, and stomatal conductance) increased significantly; however, the MDA content, H2O2 accumulation, and rate of superoxide radical production showed a remarkable decrease compared with the enhanced UV-B treatment alone. These results implied that the appropriate dose of low-energy N+ ion beam treatment may alleviate the damage caused by the enhanced UV-B radiation on rice. 相似文献
20.
Fluorescence spectroscopic studies on binding of a flavonoid antioxidant quercetin to serum albumins
Beena Mishra Atanu Barik K. Indira Priyadarsini Hari Mohan 《Journal of Chemical Sciences》2005,117(6):641-647
Binding of quercetin to human serum albumin (HSA) was studied and the binding constant measured by following the red-shifted
absorption spectrum of quercetin in the presence of HSA and the quenching of the intrinsic protein fluorescence in the presence
of different concentrations of quercetin. Fluorescence lifetime measurements of HSA showed decrease in the average lifetimes
indicating binding at a location, near the tryptophan moiety, and the possibility of fluorescence energy transfer between
excited tryptophan and quercetin. Critical transfer distance (R
o
) was determined, from which the mean distance between tryptophan-214 in HSA and quercetin was calculated. The above studies
were also carried out with bovine serum albumin (BSA). 相似文献