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1.
The amounts of flavonoid (myricetin , quercetin and kaempferol), antioxidant contents ( total phenolic and total flavonoid) and antioxidant activities (DPPH and FRAP) were analyzed in strawberry. Quantitative analysis of conjugated flavonoid contents were obtained after different hydrolysis concentration and reaction period . The highest yields of myricetin and quercetin were found with 1.0M HCl and a reaction period of 0.5 hr, however , for kaempferol was 1.0M HCl and a reaction period of 1hr , respectively. In the study, we also estimated the correlation coefficient of TPC, TFC, DPPH and FRAP. In addition , a positive correlation was observed ( r = 0.980, P < 0.05) between TPC and TFC, TPC and TFC are correlated to the DPPH activity (r = 0.913, P < 0.05 and r = 0.899 , P < 0.05 , respectively) , and to the FRAP activity ( r = 0.958, P < 0.05 and r = 0.936, P < 0.05, respectively), respectively. These results pointed out that strawberry generally possesses a high level of antioxidant activities, which could be linked to the levels of phenolic compounds in the fruit.  相似文献   

2.
The aim of present work was to assess the total phenolic content (TPC), total flavonoid content (TFC), phenolic compounds and antioxidant properties of various extracts of three Ceropegia spp.: Ceropegia spiralis, Ceropegia panchganiensis and Ceropegia evansii from Western Ghats of India. TPC of the samples varied from 0.3 ± 0.2 to 28.5 ± 0.3 mg TAE/g FW, whereas, TFC of the samples ranged between 0.1 ± 0.1 and 15.3 ± 0.3 mg RE/g FW. The major phenolic compounds identified were gallic acid, vanillin, cathechol and ferulic acid. All the extracts possess 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP) as well as metal chelating ability and this was also supported by significant correlation with TPC and TFC. To the best of our knowledge, this is the first paper presenting comprehensive data on TPC, TFC, phenolic profile and antioxidant properties of the Ceropegia spp.  相似文献   

3.
报道草莓中黄酮类物质含量的测定方法,并比较了总抗氧化成分与抗氧化活性(DPPH,FRAP)之间的相互关系.黄酮类物质的水解随着HCl浓度和水解时间的不同发生较大的差异,结果表明,总多酚类物质和总黄酮类物质之间有很高的相关关系,总多酚类物质和总黄酮类物质对DPPH有很高的相关关系,而且总多酚类物质和总黄酮类物质对FRAP的相关关系各为r=0.958, P <0.05和r=0.936, P <0.05,从结果可以推测:草莓体现出很强的抗氧化活性,这与草莓中的总多酚类物质成分密不可分.  相似文献   

4.
Non-destructive methods have been widely recognized for evaluating fruit quality traits of many horticultural crops and food processing industry. Destructive (analytical) test, and non-destructive evaluation of the quality traits were investigated and compared for ‘Red Rose’ tomato (Solanum lycopersicum L.) fruit grown under protected environment. Fresh tomato fruit at five distinctive maturity stages namely; breaker (BK), turning (TG), pink (PK), light-red (LR), and red (RD) were labeled and scanned using the handheld near infra-red (NIR) enhanced spectrometer at a wavelength range of 285–1200 nm. The labeled tomato samples were then measured analytically for flesh firmness, lycopene, β-carotene, total phenolic content (TPC) and total flavonoids content (TFC). The results revealed that quality traits could be estimated using NIR spectroscopy with a relatively high coefficient of determination (R2): 0.834 for total phenolic content, 0.864 for lycopene, 0.790 for total flavonoid content, 0.708 for β-carotene; and 0.679 for flesh firmness. The accumulation of Lyco and β-Car rapidly increased in tomatoes harvested between the TG and the LR maturity stages. Harvesting tomatoes at BK maturity stage resulted in significantly higher flesh firmness than harvesting at the later maturity stages. Tomato fruits had the lowest TPC and TFC contents at the earliest maturity stage (BK), while they had intermediate TPC and TFC levels at LR and RD maturity stages. NIR spectroscopic measurements of fruit firmness and lipophilic antioxidants in tomato fruit at various maturity stages were partially in accordance with those estimated by destructive (analytical) methods. Based on these findings, we recommend using non-destructive NIR spectroscopy as an effective tool for predicting tomato fruit quality during harvest stage and postharvest processing.  相似文献   

5.
A potential antioxidant resource: Endophytic fungi from medicinal plants   总被引:3,自引:0,他引:3  
Medicinal plants and their endophytes are important resources for discovery of natural products. Several previous studies have found a positive correlation between total antioxidant capacity (TAC) and total phenolic content (TPC) of many medicinal plant extracts. However, no information is available on whether such a relationship also exists in their endophytic fungal metabolites. We investigated the relationship between TAC and TPC for 292 morphologically distinct endophytic fungi isolated from 29 traditional Chinese medicinal plants. The antioxidant capacities of the endophytic fungal cultures were significantly correlated with their total phenolic contents, suggesting that phenolics were also the major antioxidant constituents of the endophytes. Some of the endophytes were found to produce metabolites possessing strong antioxidant activities. Several bioactive constituents from the fungal cultures and host plant extracts were identified. This investigation reveals that the metabolites produced by a wide diversity of endophytic fungi in culture can be a potential source of novel natural antioxidants.  相似文献   

6.
Salacia chinensis L. has various beneficial properties including antidiabetic and antioxidant activity. The S. chinensis fruit pulp (SCFP) was extracted with four different solvents (Methanol, ethanol, acetone and water) and was screened for total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (AOA). The AOA was assessed by evaluating the 1, 1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and metal chelating assay. Methanolic SCFP extract exhibited the highest phenolic content (3.20?±?0.12 mg GAE/g FW) whereas, ethanolic extract showed highest flavonoid content (0.31?±?0.68 mg RE/g FW). The methanolic extract possesses highest antioxidant activity towards DPPH (92.44 %), FRAP (1.939 O.D) and metal chelating activity (74.16 %). AOA (DPPH and FRAP) was significantly correlated with TPC. The results indicated that SCFP is a good natural source of antioxidant compounds for use in food and pharmaceutical industry.  相似文献   

7.
Modelling of anaerobic digestion systems is difficult because their performance is complex and varies significantly with influent characteristics and operational conditions. In this study, Adaptive Neuro-Fuzzy Inference System (ANFIS) were used for modelling of anaerobic digestion system of primary sludge of Kayseri municipal WasteWater Treatment Plant (WWTP). Effluent Volatile Solid (VS) and methane yield were predicted by the ANFIS. Two stage models were performed. In the first stage, effluent VS concentration was predicted using pH, VS concentration, flowrate of pre-thickened sludge and temperature of the influent as input parameters. In the second stage, effluent VS concentration in addition to first stage input parameters were used as input parameters to predict methane yield. The low Root Mean Square Error (RMSE) and high Index of agreement (IA) values were obtained with subtractive clustering method of a first order Sugeno type inference. The model performance was evaluated with statistical parameters. According to statistical evaluations, the models satisfactorily predict effluent VS concentration and methane yield.  相似文献   

8.
The effects of different conditioning treatments (fresh, freezing, freeze‐drying, oven‐drying and greenhouse‐drying) on the total phenolic content (TPC) and antioxidant activities of two brown algae, Sargassum muticum and Bifurcaria bifurcata, were investigated and compared. Phenolic compounds were extracted in a methanol/water (50:50) solution, and TPC was measured by the colorimetric Folin‐Ciocalteu assay. Antioxidant activity was assessed by the DPPH (2, 2‐diphenyl‐1‐picrylhydrazyl) radical scavenging assay and the β‐carotene bleaching method. The dried seaweeds showed lower phenolic contents and lower antioxidant capacities than the fresh and frozen ones, which suggests that the phenolic content and antioxidant activities are decreased by the drying treatments, especially, oven‐ and greenhouse‐drying. Relationships between TPC, antioxidant properties and conditioning treatments are discussed.  相似文献   

9.
This paper shows a quantitative relation between the regularization techniques, the generalization ability, and the sensitivity of the Multilayer Perceptron (MLP) to input noise. Although many studies about these topics have been presented, in most cases only one of the problems is addressed, and only experimentally obtained evidence is provided to illustrate some kind of correlation between generalization, noise immunity and the use of regularization techniques to obtain a set of weights after training that provides the corresponding MLP with generalization ability and noise immunity. Here, a new measurement of noise immunity for a MLP is presented. This measurement, which is termed Mean Squared Sensitivity (MSS), explicitly evaluates the Mean Squared Error (MSE) degradation of a MLP when it is perturbed by input noise, and can be computed from the statistical sensitivities (previously proposed) of the output neurons. The MSS provides an accurate evaluation of the MLP performance loss when its inputs are perturbed by noise and can also be considered a measurement of the smoothness of the error surface with respect to the inputs. Thus, as the MSS can be used to evaluate the noise immunity or the generalization ability, it gives a criterion to select among different weight configurations that present a similar MSE after training.  相似文献   

10.
This article presents an optimized ultrasound-assisted ethanolic extraction (UAEE) and characterization of selected high-value components from Gemlik olive fruit (GOF) harvested from Potohar region of Pakistan. Response surface methodology (RSM), involving central composite design (CCD), was applied to optimize the extraction variables i. e., temperature (25–65 °C), extraction time (15–45 min) and aqueous ethanol concentration (60–90 %) for optimal recovery of bioactives extract, total phenolic contents (TPC) and DPPH free radical scavengers. Under the optimized set of conditions such as 43 °C temperature, 32 min extraction time and 80 % aqueous ethanol, the best extract yield (218.82 mg/g), TPC (19.87 mg GAE/g) and DPPH scavenging activity (63.04 %) were recorded. A quadratic polynomial model was found to be reasonably fitted to the observed results for extract yield (p<0.0001 and R2=0.9941), TPC (p<0.0001 and R2=0.9891), and DPPH radical scavenging activity (p<0.0001 and R2=0.9692). Potent phenolic compounds were identified by GC/MS in GOF extract and considerable amount of essential fatty acids were also detected. The current findings support the use of UAEE as an effective green route for optimized recovery of high-value components from GOF and hence its applications can be extended to functional food and nutra-pharmaceutical developments.  相似文献   

11.
Thamnidium elegans CCF 1456, a filamentous fungus, was used to enhance the total phenolic content and radical scavenging activity of maize via solid-state fermentation. Thamnidium fermented maize (TFM) and unfermented maize (UFM) grains were extracted with 65% ethanol and dimethylsulfoxide (DMSO). Total phenolic content (TPC), and radical scavenging capacity — determined with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and radical cations of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS·+) found for TFM — were significantly (P < 0.05) higher on the 5th day of incubation than that of UFM extracts. A linear correlation was observed among TPC, DPPH and ABTS scavenging activities, and also among TPC and various carbohydrate-cleaving enzymes (α-amylase, β-glucosidase and xylanase), suggesting that this? strategy may help to enrich? TFM with improved phytochemical properties and antioxidant activities.  相似文献   

12.
The aim of this study was to test the effects of temperature on phenolic content of the brown seaweed Cystoseira amentacea. Phenolic compounds are secondary metabolites involved in different protection mechanisms as, for example, against grazers, epiphytes and UV radiation. Seasonal variations of phenolic content in C. amentacea were analysed and laboratory experiments, in which C. amentacea was exposed to an increase of temperature (25°C and 30°C), were performed. Total phenolic content (TPC) was determined colorimetrically with the Folin–Ciocalteu reagent. In C. amentacea, a seasonal pattern in TPC was observed, with a maximum value in winter-spring. C. amentacea responded significantly to the temperature treatments with a consistent decrease in TPC after 48 h.  相似文献   

13.

The present study was aimed at investigating the effects of different concentrations of sodium alginate (NaAlg) (0.075 and 0.15% (w/v)) on the production of secondary metabolites (SMs) and antioxidant activity of seven safflower genotypes under in vitro salinity stress. The results showed that total phenolic content (TPC), total flavonoids (TFD), total flavonols (TFL), anthocyanin (Ant), total antioxidant capacity (TAC), phenylalanine ammonia-lyase (PAL), catalase (CAT) activity, and lipid peroxidation significantly increased under salinity stress consisting of the concentration of 1.5% (w/v) of NaCl, but callus growth traits decreased. The highest amount of TPC, Ant, and callus growth traits was observed under the elicitation of the sample with the concentration of 0.075(%) NaAlg under salinity stress, but the highest amount for TFD, TFL, CAT, PAL, and TAC was observed under elicitation of the sample with the concentration of 0.15% of NaAlg under salinity stress. This indicated the superiority of NaAlg for elicitation to increase SMs in safflower under salinity stress. Overall, the results showed that genotypes of Mex.22-191 and GE62918 could be processed to produce SMs by eliciting NaCl in safflower as an important medicinal plant at cellular level. A positive and significant correlation between CAT and TPC was observed and indicates that phenolic compounds are the major contributors to the antioxidant potential in safflower. This new elicitor introduced new ways to select and exploit the best NaAlg concentration to develop SMs that are of tremendous importance in terms of commercial purposes along with medical features in safflower at cellular level.

  相似文献   

14.

Pomegranate (Punica granatum L.) has widely been used as a fruit and in folk medicine since ancient civilizations in the world. It is now known that bioactive compounds present in pomegranates attribute to its therapeutic potential. Harvesting at the correct maturity stage is one of the key factors deciding the quality of harvest for consumption in fresh or value-added forms. Identification of the correct maturity stage (harvesting index) is particularly difficult for cultivars having yellowish peel and pinkish arils (sarcotesta). We studied the changes in total phenolic content (TPC), antioxidant activity (AOX), punicalagin α and β contents, color indices, total soluble solids (TSS), and expression of anthocyanin biosynthetic pathway genes from flowering to harvesting in the pomegranate cultivar Nimali, having red flowers, yellow peels, and pinkish arils at maturity over two growing seasons. Interestingly, there was no seasonal variation observed in any of the parameters over two cultivation seasons. Although the β punicalagin content did not change, the TPC, AOX, punicalagin α contents in both peel and arils gradually decreased from flowering to maturity. Though the TPC of both peels and arils, AOX and total punicalagin content of peel did not change significantly 140 days after flower initiation, the TPC and the total punicalagin of arils reached a stable level at 160 days. The TSS in both peels and arils increased significantly with the maturity having the highest values at 180 days. The peel color changed from green to yellow with maturity with a significant increase in l* and b* values and significant decrease in a* value. Nevertheless, the aril color changed from pale white to pink with the maturity with significant reduction of l* and b* values and significant increase of a* value. Changes in pomegranate dihydroflavonol 4-reductase (DFR), flavanone 3-hydroxylase (F3H), and leucoanthocyanidin dioxygenase (anthocyanidin synthase-ANS) gene expression in Nimali arils correlated with its color changes during maturity. These findings support to identify the harvesting index of Nimali ensuring the maximum nutritional and health benefits of pomegranate flower, arils, and peels for different downstream uses.

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15.
Our previous study showed that flowers of Agastache rugosa had higher phenolic levels and higher antibacterial and antioxidant capacity compared to those of the leaves and stems. The aim of this study was to provide information on the variation in primary and secondary metabolites during flower development in A. rugosa by using high performance liquid chromatography (HPLC) and assays of total anthocyanin (TAC), flavonoid (TFC), and phenolic content (TPC), as well as gas chromatography time-of-flight mass spectrometry (GC-TOFMS) analysis. Assays of TPC, TAC, and TFC showed that the floral bud (stage I) contained higher TPC than did the partially open flower (stage II) and fully open flower (stage III). However, the TFC was the highest at stage II, and the highest TAC was observed at stage III. Furthermore, HPLC analysis revealed that the level of total phenylpropanoids, including rosmarinic acid, tilianin, acacetin, 4-hydroxybenzoic acid, caffeic acid, chlorogenic acid, trans-cinnamic acid, rutin, (-)-epicatechin, quercetin, and kaempferol, was higher in stages I and II, but the concentrations of rutin and rosmarinic acid were highest in stage III. A total of 43 compounds, including amino acids, organic acids, phenolic compounds, sugars, photorespiration-related compounds, and intermediates of the tricarboxylic acid cycle, were identified through GC-TOFMS analysis. Of these compounds, most amino acids decreased during flower development. In contrast, the increase in concentrations of glucose and sucrose were observed from stages I to III. In this study, health-beneficial compounds were identified and quantified in flowers of A. rugosa. Accordingly, our results suggests that A. rugosa flowers can potentially be used as biomaterials for pharmaceuticals, cosmetics, food, and related industries.Supplementary informationThe online version contains supplementary material available at (10.1007/s12298-021-00945-z).  相似文献   

16.
Although the physiological states of hypertrophic remodeling and congestive heart failure have been intensively studied, less is known about the transition from one to the other. The use of genetically engineered murine models of heart failure has proven valuable in characterizing the progression of remodeling and its ultimate decompensation to failure. Mice deficient in the cytoskeletal muscle LIM-only protein (MLP) are known to present with a clinical picture of dilated cardiomyopathy and transition to failure as adults. Longitudinal high-field magnetic resonance (MR) cardiac imaging provided a time course of remodeling where an improvement in ejection fraction and stroke volume (15- vs. 31-wk MLP(-/-) mice; P < 0.0001) was temporally concurrent with an abrupt phase of end-diastolic chamber dilatation. Hemodynamic analysis conducted throughout that dilatation phase showed improved ratio of maximum first derivative of pressure to end-diastolic pressure (dP/dt(max)/EDP; 15- vs. 31-wk MLP(-/-) mice; P < 0.0005), ratio of minimum first derivative of pressure to EDP (dP/dt(min)/EDP; 15- vs. 31-wk MLP(-/-) mice; P < 0.003), and developed pressure (15- vs. 31-wk MLP(-/-) mice; P < 0.0001) levels in the MLP(-/-) mice. Computational modeling techniques were used to estimate the EDP volume relationship, revealing that although MLP hearts possess a stiffer stress-strain relation, chamber compliance increased as a function of dilatation. This detailed physiological characterization during a phase of rapid anatomical remodeling suggests that systolic function in the MLP(-/-) mice may temporarily improve as a result of alterations in chamber compliance, which are mediated by dilatation. In turn, a balance may exist between exploiting the Frank-Starling mechanism and altering chamber compliance that maintains function in the absence of hypertrophic growth. Though initially compensatory, this process may exhaust itself and consequently transition to a maladaptive course.  相似文献   

17.
Cultivation of Spirulina platensis using ammonium salts or wastewater containing ammonium as alternative nitrogen sources is considered as a commercial way to reduce the production cost. In this research, by analyzing the relationship between biomass production and ammonium- N consumption in the fed-batch culture of Spirulina platensis using ammonium bicarbonate as a nitrogen nutrient source, an online adaptive control strategy based on optical density (OD) measurements for controlling ammonium feeding was presented. The ammonium concentration was successfully controlled between the cell growth inhibitory and limiting concentrations using this OD-based feedback feeding method. As a result, the maximum biomass concentration (2.98 g/l), productivity (0.237 g/l·d), nitrogen-to-cell conversion factor (7.32 gX/gN), and contents of protein (64.1%) and chlorophyll (13.4 mg/g) obtained by using the OD-based feedback feeding method were higher than those using the constant and variable feeding methods. The OD-based feedback feeding method could be recognized as an applicable way to control ammonium feeding and a benefit for Spirulina platensis cultivations.  相似文献   

18.
19.
Propolis is one of the mixtures with the widest biological activity among natural products used in complementary medicine. HSV-1 is a highly contagious and endemic virus. Available drugs are insufficient for recurrent HSV-1 infections. Therefore, new approaches to treat HSV-1 infections are still being developed. In this study, it was aimed to investigate the inhibition effect of ethanolic Anatolian propolis extracts obtained from the Eastern Black Sea Region (Pazar, Ardahan, and Uzungöl) on HSV-1. In addition to the total phenolic (TPC) and the total flavonoid content (TFC), the phenolic profiles of the extracts were analyzed by HPLC-UV. The antiviral activity of the extracts were tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), quantitative Real Time Polymerase Chain Reaction (qRT-PCR), and plaque reduction tests, and the results were evaluated statistically. It was determined that the total amount of phenolic substances varied between 44.12 and 166.91 mg GAE/g, and the total flavonoid content of the samples varied between 12.50 and 41.58 (mg QUE/g). It was shown that all propolis samples used in the current study were effective against HSV-1, but the higher phenolic compounds contained in the samples showed the higher activity. The results show that ethanolic propolis extracts are promising candidates for HSV-1 treatment.  相似文献   

20.
In present study, the capabilities of multiple linear regression (MLR) and adaptive neuro-fuzzy inference system (ANFIS) in developing pedotransfer functions (PTFs) for estimating geometric mean diameter (GMD) and mean weight diameter (MWD), from routine soil properties and combination of routine soil properties and fractal dimension of aggregates were evaluated. For this reason 101 samples were collected form the Northwest of Iran and some their properties such as soil texture, pH, cation exchange capacity (CEC), and organic matter (OM), fractal dimension of aggregates between number-diameter (Dn), mass-diameter (Dmt), and bulk density-diameter (Dmy) were determined and used as an input variables for determining of mean weight diameter (MWD) and geometric mean diameter (GMD) by MLR and ANFIS PTFs. Results showed that the application of fractal dimension of aggregates as a predictor in two methods improved the accuracy of PTFs. As well as, results showed that ANFIS have greater potential for determination of the relationships between soil aggregate stability indices and other soil properties in compared with MLR. Therefore using of adaptive neuro-fuzzy inference system (ANFIS) in developing pedotransfer functions is recommended.  相似文献   

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