how to calculate ec50 value for antioxidant activity usinghow to calculate ec50 value for antioxidant activity using

Chye, F. Y., Wong, J. Y., and Lee, J.-S. (2008). Asample = Absorbance of sample after 45 min. The concentration that provokes a response of 50 in this experiment is not the EC50. All water and methanolic extracts possess phenolics compounds and flavonoids. The antioxidant activity was calculated by using the following equation. Could you (or anybody else) please further explain how to do that. Food Sci. (2014) investigated the antioxidant activity and the total polyphenol amount, of methanol extracts of mycelium and fruiting body of P. sajor-caju, P. ostreatus and P. sapidus. FIGURE 2. Screening of radical scavenging activity of some medicinal and aromatic plant extracts. 2014, 18. Othman A, Ismail A, Ghani NA, Adenan I. Antioxidant capacity and phenolic content of cocoa beans. This value is particularly important in pharmacology, because it serves as an indication of drug potency. In this analysis, the dried samples showed higher radical scavenging activity of ABTS than the fresh samples (Table 6). Arbaayah, H. H., and Umi, K. Y. In general, values of antioxidant activity of extracts of fresh samples were higher with respect to the dried samples. Bio. Yim et al. TABLE 4. Res. 8600 Rockville Pike where ln is natural log, a is the initial absorbance (at 470 nm) at time 0, b is the absorbance (at 470 nm) at 20, 40, 60, 80, 100 or 120 min and t is the initial absorbance (470 nm) at time 0. The EC50 values were calculated from the graph which represents the concentration of the sample required to scavenge 50% of the chelating effect. Guzmn et al. Chia-Chi, C., Ming-Hua, Y., Hwei-Mei, W., and Jiing-Chuan, C. (2002). (2011) found in methanol extracts of P. ostreatus and P. dryinus high antioxidant 11600 and 2385.71 M de FeSO4/g. Concentration changes of malondialdehyde across the cerebral vascular bed and shedding of L-selectin during carotid endarterectomy. Pro- and antioxidative properties of medicinal mushroom extracts. Slowly, 0.5 mL sample was taken and was mixed with 1.5 mL of 95% ethanol, 0.1 mL of 10% aluminum chloride, 0.1 mL of 1 M potassium acetate and 2.8 mL of distilled water. The hydroxyl radical scavenging activity of EESTG and the positive controls (BHT and quercetin) at different concentrations (50, 100, 200, 400, 800 g/ml) are shown in Figure 6. [4] IC 50 values can be used to compare the potency of two antagonists. (2015). After 30 min incubation in the dark and at room temperature, absorbance (A) was measured at 518 nm using a UV/VIS spectrometer -T70. Nanjo F, Goto K, Seto R, Suzuki M, Sakai M, Hara Y. Scavenging effects of tea catechins and their derivatives on 1,1-diphenyl-2-picrylhydrazyl radical. Food Process Technol. The result is normally expressed using the EC 50 value, defined as the concentration of antioxidant that causes a 50% decrease in the DPPH absorbance. Here is what I do, so just tell me if I`m doing it right: x-axis is log values of concentration, y is Inhibition(%) than I plot that, and perform DoseResp analysis(just by opening the dialog, selecting DoseResp under function and than I click fit). Koudou J, Roblot G, Wylde R. Tannins constituents of Terminalia glaucescens. It was observed that the antioxidant activity measured by FRAP was positively correlated to the concentration of the polyphenols. The aqueous extracts showed similar values about 45 mg GAE/g. The spawn was obtained by inoculation of wet and sterile wheat grains (500 g) with 10 mycelium plugs taken from the peripheral of a colony by using a sterile cork borer (4 mm diam). They also found in their methanol extracts a low antioxidant activity of mushroom Hydnum repandum with 145.50 M de FeSO4/g. After incubation for 45 min, absorbance was determined in a spectrophotometer at 517 nm. Biomed. 50, 60726077. Association of Official Analytical Chemists [AOAC] (2000). Metal ion chelating activity was expressed as mg GAE/L. We evaluated the total phenolic content (TPC), total flavonoid content (TFC), DPPH free radical scavenging, reducing power, total antioxidant based on phosphomolybdate method, hydroxyl radical scavenging and -carotene-linoleate bleaching activities of the extract. Slowly, 0.5 mL of sample was added to 4.5 mL of distilled water and was mixed with 0.2 mL of the FolinCiocalteu phenol reagent and 0.5 mL saturated solution of Na2CO3, finally 4.3 mL of distilled water was added to the solution. After cooling, the absorbance was measured at 532 nm against a blank containing deoxyribose and buffer. The different results also suggested that antioxidant activity couldnt be by polyphenols. The absorbance was read at 20 min intervals for 2 h at 470 nm, using UV/VIS spectrometer T70. Asia 35, 326331. (2009). Weigand MA, Laipple A, Plaschke K, Eckstein HH, Martin E, Bardenheuer HJ. Mau, J. L., Lin, H. C., and Chen, C. C. (2002). TABLE 3. You do this on the Parameters tab. TABLE 5. The EC50 values were calculated from the graph which represents the concentration of the sample required to scavenge 50% of the ABTS or DPPH free radicals. nikolajeremic. Tecnol. In addition to the phytochemicals, fungi have also been considered as a source of biologically active substances that can be used to reduce oxidative damage in humans and useful in disease prevention (Chye et al., 2008; Fatih et al., 2010; Adebayo et al., 2012; Shirmila and Radhamany, 2012). (2016), reported that the mushrooms do not contain flavonoids, and those found in the hyphae could be due to the facility of these organisms to absorb many nutrients and compounds from the substrate where they grow or from neighboring plants by spreading their hyphae or forming mycorrhizae. 26, 12311237. [25] An aliquot of 0.1 ml of the fractions (50-800 g/ml) was combined with 1.0 ml of reagent (0.6 M sulfuric acid, 28 mM sodium phosphate and 4 mM ammonium molybdate). Both extracts of A. brasiliensis showed higher content of total flavonoids than extracts of A. bisporus. Ferric reducing antioxidant power assay was measured according to the procedure described by Sudha et al. The Review of Natural Products I, Facts and Comparison; p. 637. It was observed that the DPPH radical scavenging activity was positively correlated to the concentration of the extract. 139). Malic acid was the most abundant organic acid (1.82 g/100 g), followed by citric acid (0.88 g/100 g), then fumaric acid (0.26 g/100 g) and oxalic acid (0.09 g/100 g). The dried sample was grinded to powder, sieved and packed into polythene bags and stored at 4C. (2011) reported the flavonoids content from ethanolic, cold water and hot water extracts of two strains of Grifola frondosa; values were 1.093.05 and 0.110.76 mg EQ/g of sample dry, respectively. Quantitation of nine organic acids in wild mushrooms. doi: 10.1016/S2221-1691(12)60194-4. The total antioxidant capacity was expressed as g equivalents of BHT by using the standard BHT graph. Korley, K. N., Tawia Odamtten, G., Obodai, M., Appiah, V., Akuamoa, F., Adu-Bobi, A. K., et al. In methanol extracts of Pleurotus sp. Food Chem. 21, 661668. doi: 10.2306/scienceasia1513-1874.2009.35.326, Re, R., Pellegrini, N., Proteggente, A., Pannala, A., Yang, M., and Rice-Evans, C. (1999). Miller AL. Nutritional quality and antioxidant activity of selected edible wild mushrooms. Values are the average of duplicate experiments and represented as mean standard deviation, EC 50 values of -ethanol extract of the stem bark of Terminalia glaucescens [EESTG] and the standard, vit. Reducing power assay of methanolic extracts of fresh P. ostreatus. 77, 229235. Sudha et al. This mixture was incubated at room temperature for 30 min in darkness. We found the value of the TPC of the extract to be 596.57g GAE/mg extract. Both values are lower than those reported in this study for the aqueous extract of fresh fruiting body obtained by boiling (9.92 0.05 mg GAE/g) and the aqueous extract of the dry fruiting body obtained at room temperature (11.36 mg GAE/g). Barros, L., Joo, F. M., Queirs, B., Ferreira, I. C., and Baptista, P. (2007). Velioglu YS, Mazza G, Gao L, Oomah BD. doi: 10.1016/j.jff.2016.05.005, Gioti, E. M., Fiamegos, Y. C., Skalkos D. C., and Stalikas, C. D. (2009). Values are the average of three replicates DS. The value reported was lower compared with that observed in this investigation in methanolic extract obtained at room temperature and boiling of the dried fruiting body with EC50 = 217.24 1.31 and 76.63 0.070 mg GAE/L, respectively. The baseline is about 20%, and the maximum is 100%, so the EC50 is the concentration of agonist that evokes a response of about 60% (halfway between 20% and 100%). Test samples were kept at 37C for 1 h. The free radical damage imposed on the substrate, deoxyribose, was measured using the thiobarbituric acid test. Our result confirms the presence of flavonoids in the extract based on quercetin as the reference compound and the TFC expressed in microgram quercetin equivalents per milligram (g QE/mg) of dry extract. Antioxidative properties of xanthan on the autoxidation of soybean oil in cyclodextrin emulsion. J. The statistical estimation gave similar EC 50, but the five-parameter GraphPa. 5, 161166. 3 Posts. Antioxidant flavonoids: Structure, function and clinical usage. Fungi produce a considerable amount of metabolites, including vitamin C, vitamin E, and beta-carotene as well as phenolic compounds, known as excellent antioxidants (Barros et al., 2007; Chye et al., 2008; Yin et al., 2008; Fatih et al., 2010; Keles et al., 2011; Adebayo et al., 2012; Shirmila and Radhamany, 2012). Flora of West Pakistan; pp. (2009). Figure 1 shows our result on the reducing power activity of EESTG. Gil-Ramrez, A., Pavo-Caballero, C., Baeza, E., Baenas, N., Garcia-Viguera, C., Marn, F. R., et al. Superoxide, superoxide dismutase and oxygen toxicity. Food Sci. In general, the extracts of dried samples showed higher reducing power than the extracts of fresh samples and tend to show greater reducing power by aqueous than methanolic extracts. Quercetin and BHT (50800 g/ml) were used as positive controls. 6, 4147. Study on in vitro antioxidant potential of some cultivated Pleurotus species (Oyster mushroom). The results were also expressed as AEAC (Ascorbic acid equivalent antioxidant capacity) i.e. Antioxidants in fruits and vegetables-the millennium's health. The value obtained by second and third region was higher than the value reported for the aqueous extracts (obtained by boiling) of dried and fresh fruiting bodies and methanolic extract (obtained at room temperature) of fresh fruiting body. Chloroform was removed at room temperature under vacuum at reduced pressure using a rotary evaporator (RE-52A, Shanghai Ya Rong Biochemistry Instrument Factory, Shanghai). The ABTS+ solution was diluted with water to an absorbance of 0.70 (0.02) at 734 nm. (2008) with some modifications. 111. [25] A correlation between degradation rate and bleaching of -carotene displays that EESTG with the lowest -carotene degradation rate exhibited the highest antioxidant activity. It was identified by a plant taxonomist in the Department of Botany, University of Ibadan, Nigeria and a voucher specimen was deposited in the Herbarium of same Department with the Herbarium number UIH-22404. Your choice of modeling IC50 or EC50 is simply based on whether you're modeling an inhibitor (antagonist) or a stimulant (agonist). J. The absorbance was measured at 700 nm. doi: 10.1016/j.fct.2012.02.013, Joan-Hwa, Y., Hsiu-Ching, L., and Jeng-Leun, M. (2002). The percentage of the radical scavenging activity (RSA) was calculated based on the following equation: Acont and Asample are the absorbance values (at 518 nm) for the control and sample, respectively. Total phenolic content was expressed as mg of Gallic acid equivalents (GAE) per gram of dry sample (mg GAE/g). The results of the metal ion chelating activity indicate that all extracts tested had acted. Analysis of total phenols and other oxidation substrates and antioxidants by means of Folin-Ciocalteu reagent. Koleva II, van Beek TA, Linssen JP, de Groot A, Evstatieva LN. Resour. The antioxidant activity measured by FRAP method was observed in all extracts (Table 3). Furthermore, treatment of boiling for extraction favored the DPPH radical scavenging activity, since these extracts showed higher activity than the extracts obtained at room temperature, except for the methanol extract of dry fruiting body and dry primordium obtained at room temperature, which they showed the lowest values of EC50 (30.89 1.83 and 26.99 0.47 mg GAE/L, respectively). Singleton, V. L., Orthofer, R., and Lamuela-Ravents, R. M. (1999). USA. In pharmacology, a dose-response experiment determines the effects of a drug on cells grown in vitro. The reaction mixture was incubated at 37C for 10 min and the absorbance was measured at 593 nm. For fresh samples, methanolic extract of primordium and aqueous extract of the fruiting body, showed the highest polyphenols values, 12.06 0.02 and 9.92 0.05 mg GAE/g, respectively. Several research had proven the antioxidant activity of different mushrooms. Still, it is necessary to enrich the diet with antioxidants (Adebayo et al., 2012) contained in food to help the organism to reduce oxidative damage (Joan-Hwa et al., 2002; Fatih et al., 2010). 2, 392401. Food Res. 2, 247251. Karachi: Ferozsons; 1978. [36] The principle of this assay involves the activity of an antioxidant compound which leads to reduction of the hexavalent form of molybdenum [Mo (VI)] to the pentavalent form [Mo (V)], and the formation of a green phosphate/Mo (V) complex at acidic pH and at higher temperature. All the analyses were run in triplicate and averaged. The methanolic extract (obtained by boiling) of the dried micelium of this study, showed better chelating activity (EC50 = 13.17 0.13 mg GAE/L) than the petroleum ether extract of Pleurotus sp. Two milliliter (2 ml) aliquots of the emulsion were pipetted into test tubes and immediately placed in a water bath at 50C. One peculiarity of this method is that it allows testing of both lipophilic and hydrophilic compounds[37,38] in comparison to other methods that are restricted in the nature of antioxidants that they can be used to quantify. Reducing power assay of aqueous extracts of fresh P. ostreatus. 299, 152178. We choose the convention for the remaining article to discuss the half-maximal response in terms of IC50. The results suggested that antioxidant activity could be due to polyphenols, but mainly by different molecules or substances present in the extracts. It was observed that aqueous extracts showed generally higher DPPH radical scavenging activity than methanol extract samples in both dry and fresh. Free radical scavenging and total phenolic contents from methanolic extracts of. Shirmila, J. G., and Radhamany, P. M. (2013). Sci. 50 g/ml), EESTG, ascorbic acid and butylated hydroxytoluene (BHT) had activity values corresponding to 0.0830 0.0101, 0.0247 0.0055, and 0.1750 0.0113, respectively. One ml of 1% thiobarbituric acid (TBA) and 1.0 ml 2.8% trichloroacetic acid (TCA) were added to the test tubes and were incubated at 100C for 20 min. (2012) reported the flavonoids content in ethyl acetate, methanol and hot water extracts of P. eous, reaching values of 6.38 to 7.79 mg catechin equivalents (CAE)/g extract. Agro. At the minimum concentration of extract/standards used in this study (i.e. All tests were performed in triplicate and the graph was plotted with the average of the three determinations. Specifically, EESTG displayed a significantly (P < 0.001) higher anti-oxidant activity when compared to BHT, and the activity of EESTG was higher than that of quercetin although not significant (P = 0. The results of the metal ion chelating activity indicate that all extracts tested had activity (Table 4). Sorry, I forgot to ask, also how do I calculate standard deviation for IC50 given the SE?? Arbaayah and Umi (2013) reported a high content of flavonoids from ethanol extracts of various species of Pleurotus, with values of 1.40 to 29.80 mg QE/g. Asample = Absorbance of sample after 6 min. Antioxidant activity and chemical study of the fungus Pleurotus djamor collected in Crdoba. (2012) reported 32.21 mg GAE/g in the methanol extract of P. eryngii. doi: 10.1007/s10068-012-0086-1, Valentao, P., Lopez, G., Valente, M., Barbosa, P., Andrade, P. B., Silva, B. M., et al. Using the DoseResp or Logistic function will calculate EC50/IC50 values. This affirms the potency of the extract because of its higher anti-oxidant activity as compared with the controls. EC 50 represents the concentration at which a substance exerts half of its maximal response. Lister E, Wilson P. Lincoln, New Zealand: Crop Research Institute; 2001. Sci. (2014). 156406. This fact still promisingly indicates the presence of potent phytoconstituents in EESTG that have the capability to scavenge hydroxyl radicals although the activities of such components may have been shielded by the presence of other components in the heterogenous extract. Gan, C. H., Nurul, A. 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) was dissolved in water to a 7 mM concentration. Gan et al. Don't over interpret the EC50. After incubation for 6 min, absorbance was determined in spectrophotometer at 734 nm. The GC Mass analysis revealed in some samples, mainly of the fruiting body the presence of methyltartronic acid (RT 20.185) which could be the responsiblity of the antioxidant activity. J. Microbiol. In general, the flavonoids content was reported with a low value, representing a very small percentage of the total polyphenol content, however, the majority of the extracts presented antioxidant activity. For obtaining extracts, mycelium, primordia, and fruiting bodies, both fresh and dried samples were used. Accessibility Jacob RA. Oxford: Clarendon Press; 1989. In general, extracts of the fruiting body had a high amount of polyphenols, followed by primordium and by the mycelium (Table 1). Author HE-B analyzed the statistical analysis. doi: 10.1016/j.foodchem.2006.07.038. The supernatant (0.5 mL) was added with 0.5 mL of deionised water and 0.1 mL of 0.1% FeCl3. TABLE 2. Food Chem. Furthermore, Nuran et al. Antioxidant properties of wild edible mushrooms. The reducing power of all samples was concentration dependent (Figures 14). Phenolics have received much scientific attention because they are the most widely-spread secondary metabolites in the plant kingdom and aside this, they are also known as sources of potential natural antioxidants because of their abilities to act both as efficient radical scavengers and metal chelators.[30]. Antioxidant and antidiabetic activities of extracts from Cirsium japonicum roots. Recently, it has been reported the role in health of natural antioxidants from different herbs and infusions (Chye et al., 2008; Fatih et al., 2010), seeds, oil seeds, cereals, vegetables, fruits, leaves, roots, and spices (Mau et al., 2002). Antioxidant properties of several commercial mushrooms. Recently, antioxidant activity (AOA) assays using cerium oxide . Food Chem. Biotechnology Research Center- CRBt Constantine ALGERIA. L-ascorbic acid solution (50 l, at the concentrations of 50-800 g/ml in ethanol) was used as positive control [i.e. Auddy B, Ferreira M, Blasina F, Lafon L, Arredondo F, Dajas F, et al. [40] to be 546.1, 852.8, 983.8 and 1,222.5 g/ml respectively, as compared to 145.54 g/ml and 33.72 g/ml which we obtained for EESTG and ascorbic acid respectively. Song and Leo (2008) quantified polyphenols in aqueous extracts obtained with hot water of Ganoderma lucidum, reported 0.1282.78 mg GAE/mL, and for A. brasiliensis 0.512 and 0.0853 mg GAE/mL. EC50 value, defined as the concentration of the sample leading to 50% reduction in the initial DPPH concentration, was obtained from a calibration curve for the extract. (2012). [34] It is evident from our findings that the extract possesses antioxidant activity in a concentration-dependent manner, which may imply its relevance in attenuating oxidative damage to cellular components and thereby prevent oxidative stress. Summed up together, the EC 50 and AEAC values obtained for EESTG imply that the extract contains phytochemicals with antioxidant properties. doi: 10.1080/11358120809487626. Food Chem. The reducing power of the extract was investigated by the Fe3+-Fe2+ transformation in the presence of the fractions as described by Fejes et al. Int. The antioxidant capacities of Kyoho skin, seed, and flesh extracts were determined using DPPH and ABTS assays and a suitable statistical program was tested for the prediction of EC 50 values of Kyoho skin, seed, and flesh extracts obtained by DPPH and ABTS assays. Front. Phenolic profiles of selected edible wild mushrooms as affected by extraction solvent, time and temperature. Author MT-T managed the literature searches. Prieto P, Pineda M, Aguilar M. Spectrophotometric quantitation of antioxidant capacity through the formation of a phosphomolybdenum complex: Specific application to the determination of vitamin E. Kulisic T, Radonic A, Katalinic V, Milos M. Use of different methods for testing antioxidative activity of oregano essential oil. Screening of antioxidant activity of three Indian medicinal plants, traditionally used for the management of neurodegenerative diseases. 43, 15081515. The data were analyzed using Sigma Stat software. Following evaporation, 50 ml of distilled water was added to the mixture, and then shaken vigorously to form an emulsion. Official Method of Analysis 17th Edn. Invitro antioxidant activities, total phenolics and flavonoid of wild edible mushroom Macrolepiota mastoidea (FR.) Only, the aqueous extracts of dry samples were not positively correlated to the concentration of the polyphenols. The higher the AEAC value, the greater is the antioxidant activity. In the case of extracts from dried samples, the highest value of reducing power it showed by aqueous extract obtained by boiling of fruiting body with a value of 0.701 0.003, and the methanol extract obtained at room temperature of mycelium showed 0.645 0.009, both at a concentration of 100 mg GAE/L (Figures 1 and 2). (2016). Petrovi, J., Glamolija, J., Stojkovi, D., iri, A., Barros, L., Ferreira, I. C. F. R., et al. Jeena et al. Studies on aldose reductase inhibitors from medicinal plant of sinfito, Potentilla candicans, and further synthesis of their related compounds. This calculator generates an IC 50 value typically thought of as the relative IC 50. The properties of the reducing power can be an indicator of antioxidant potential of compound evaluated (Meir et al., 1995). The methanol extracts of dried samples showed low values (between 0.62 0.012.39 0.02 mg GAE/g).