Physicochemical and Biochemical Characterization, Total Phenolic and Energy Value from Bulbs of Different Onion (Allium cepa L.) Varieties in Senegal

The purpose of this study is to investigate the physicochemical properties of some local varieties of onion (Allium cepa L.) and compare them with an imported variety, all collected in May 2021. Proteins, reducing sugars, lipids, and polyphenol content were estimated according to the AFNOR standardized methods. The determination of calcium, magnesium, iron, sodium, potassium and phosphorus was performed by atomic absorption spectrophotometer coupled with a CCD detector. The results highlighted an average acidity of 0.377% ± 0.002% lower than the value of the imported variety which is 0.520% ± 0.001%. Local varieties have a pH ranging from 6.35 ± 0.003 to 6.42 ± 0.004, while the variety has a pH of 6.36 ± 0.003. The ash and dry matter contents vary respectively from 4.788% ± 0.004% to 8.253% ± 0.003% and 7.945% ± 0.021% to 11.945% ± 0.007% for the local varieties. Moreover, the imported one has ash and dry matter contents of 5.175% ± 0.007% and 10.035% ± 0.021% respectively. The results show that the protein, reducing sugar and lipid contents in the local onion varieties vary respectively from 2.815 ± 0.000 to 15.634 ± 0.001 g·100 g-1;4.691 ± 0.001 to 12.596 ± 0.002 g·100 g-1 and 0.006 ± 0.001 to 0.050 ± 0.057 g·100 g-1. Furthermore, the imported variety has a protein, reducing sugar and lipid content of 5.649 ± 0.002;8.565 ± 0.002 g·100 g-1 and 0.011 ± 0.010 g·100 g-1 respectively. The maximum levels of total polyphenols are obtained in the imported variety, Bellani and Gandiol, respectively 9.973 ± 0.001, 4.535 ± 0.002, and 3.425 ± 0.006 mg EAG/g of dry matter. The local varieties have a significant calorific intake of between 35.451 ± 0.001 and 112.980 ± 0.003 kcal·100 g-1 compared to the imported one with an energy value of 56.953 ± 0.001 kcal·100 g-1 of dry matter. The bulbs of different onion varieties studied have a fairly high content of mineral elements. The potassium content of local varieties is between 502.16 ± 0.06 mg·100 g-1 and 582.77 ± 0.04 mg·100 g-1 while the imported variety has a content of 536.62 ± 1.30 mg·100 g-1. They note that the local varieties have a better calcium content (249.75 ± 0.07 to 434.20 ± 0.57 mg·100 g-1) and magnesium (142.15 ± 0.07 to 162.60 ± 0.42 mg·100 g-1) than the imported variety (229.58 ± 0.04 mg·100 g-1) except for the varieties White Grano (228.29 ± 0.01 mg·100 g-1) and Rouge Amposta (117.00 ± 0.42 mg·100 g-1) respectively. These results reveal that Gandiol, Dayo and Orient F1 are nutritionally found better due to their higher antioxidant property, proteins, carbohydrates, and reducing sugar and should be included in diets to supplement our daily allowance needed by the body.

Quantification of Total Phenols, Total Flavonoids, Total Anthocyanins and Evaluation of Antioxidant and Antiradical Activities of Detarium Senegalense Extracts from Chad

The aim of the present work is to assess the value of Detarium Senegalense by determining the content of total phenols, total flavonoids and total anthocyanins, and by evaluating the free radical scavenging activity of Detarium Senegalense extracts. For this purpose, sequential extraction using solvents of increasing polarity was essential. The various extracts obtained underwent phytochemical and biochemical analyses. Phytochemical screening revealed the presence of flavonoids, alkaloids, tannins, polyphenols, anthocyanins and steroids/terpenes. Quantitative analysis of total polyphenols, total flavonoids and total anthocyanins yielded the following results: total flavonoids (0.803 ± 0029 mg EQ/100g P for acetone extract of roots and 0.871 ± 0.401 mg EQ/100g P for methanol extract of leaves);total polyphenols (23.298 ± 12.68 mg EAG/100g P for acetone extract of roots and 24.69 ± 0.49 401 mg EAG/100g P for methanol extract of leaves);total monomeric anthocyanins (44.697 ± 0.939 mg EC3G/100g P and 16.699 ± 0.193 mg EC3G/100g P respectively for acetone and methanol extracts of stem bark). DPPH free radical scavenging activity was 1.674 ± 0.023 mg/mL for the acetone extract and 0.934 ± 0.24 mg/mL for the methanol extract of roots. .

Evaluation of Phytochemical Analysis and Total Phenol Content of Proso Millet and Barnyard Millet

Whole grains of proso and barnyard millets were sequentially extracted using different solvents(hexane,chloroform,ethyl acetate,and methanol).Phytochemical analysis was performed qualitatively,and the total phenolic content in the extracts of proso and barnyard millets was quantified.Alkaloids and cardiac glycosides were identified in all solvent extracts of both millets.Anthraquinone and glycosides yielded negative results in all solvent extracts of both millets.Among all the solvent extracts,methanol extracts of proso and barnyard millets showed the presence of major compounds such as flavonoids,terpenoids,amino acids,tannins,and phenolics compounds.The maximum amount of phenols was found in methanolic extracts of proso and barnyard millets(0.669±0.003 and 0.625±0.003),followed by the chloroform extract of proso and barnyard millets(0.284±0.002 and 0.257±0.003).The minimum amount of phenolics was found in the acetone extract of proso and barnyard millets.The methanol extract of both millets showed the presence of major compounds with high phenolic content.

Correlation Between Antioxidation and the Content of Total Phenolics and Anthocyanin in Black Soybean Accessions

The objective of this study was to investigate the correlations between antioxidations and the contents of the total phenolics and anthocyanin in 127 accessions of black soybean. A T-test, a fast clustering procedure, and a correlation coefficient analysis were used for experimentation. The variation ranges of the total antioxidant capacity （TAC）, the total phenolics, and anthocyanin contents in 127 black soybean accessions were 0.44-3.56, 7.05-74.82, and 0.22-1.87 mg g-l, respectively, displaying significant genotype differences. The major differences in TAC, the total phenolics, and the anthocyanin contents existed among various types of accessions from geographical regions. The differences between the accessions from black and yellow soybeans, spring and autumn, summer and autumn, Dongbeichun and Nanfangchun, Dongbeichun and Nanfangxia, Beifangchun and Nanfangchun, and Beifangchun and Nanfangxia were significant at 0.01 or 0.05 levels, respectively. The general tendency was that the TAC, the total phenolics, and the anthocyanin contents of Beifangchun accessions were higher than that of Dongbeichun ones, while that of Nanfangchun accessions were the worst. 127 black soybean accessions could be clustered into 6 clusters, which consisted of 3, 24, 20, 31, 37, and 12 accessions, respectively. The most significant （P 〈 0.01） correlations existed respectively between the TAC and the total showed that the total substances phenolics content, and the TAC and the anthocyanin content of black soybean. The results phenolics and anthocyanin in black soybean seed coat were the important antioxidation

Antioxidant activity and total phenolic content of essential oils and extracts of sweet basil(Ocimum basilicum L.)plants

The present study was conducted to evaluate the chemical composition and antioxidant activity of the essential oils and ethanol extracts of Ocimum basilicum L.obtained from Assiut,Minia and BeniSuef of Egypt.The major constituents of sweet basil essential oils from three locations were linalool,estragole,methyl cinnamate,bicyclosesquiphellandrene,eucalyptol,-bergamotene,eugenol,-cadinene and germacrene D by the method of GC–MS.The relative concentration of these compounds varies.The basil extracts contained appreciable levels of total phenolic contents and exhibited good DPPH radical scavenging capacity higher than that of essential oils.The highest TPC(82.45 mg PE/g)and maximum radical scavenging activity with IC50 value(1.29 mg/mL)was obtained from Minia basil extract.High correlation between antioxidant activity and total phenolic contents of basil extracts was observed.High variation in free radical scavenging activity of essential oils was found.The essential oil from Minia basil showed high activity in DPPH radical scavenging with IC50(11.23 mg/mL)and contained the highest content of phenolic(41.3 mg PE/g).On contrary,low correlation between antioxidant activity and total phenolic contents of basil essential oils from different locations.The results of the present investigation demonstrated significant variations in the antioxidant activities of sweet basil essential oils and extracts from Egypt.

Volatile components,total phenolic compounds,and antioxidant capacities of worm-infected Gomphidius rutilus

This study evaluated the effects of worm infection on the volatile components,total phenolic compounds,and antioxidant capacities of Gomphidius rutilus.G.rutilus without worms(GW),G.rutilus infected by a small amount of worms(GS;infected area<50%),and G.rutilus infected by a large amount of worms(GL;infected area>50%)were investigated.The volatile components of G.rutilus were analyzed by simultaneous distillation–extraction(SDE)and headspace solid-phase microextraction(HS-SPME)using gas chromatography–mass spectrometry(GC–MS).A total of 17 and 19 types of volatile compounds were detected,including ketones,alcohols,benzene,alkenes,aldehydes,esters,acids,and alkanes.Alcohols comprised the most abundant compound in GL,GS,and GW.The relative content of 1-octen-3-ol was the highest in all mushrooms.The concentration of eight-carbon(C8)compounds relative to the total volatile compounds varied widely,ranging from 40%(GW)to 64.34%(GS)and 84.42%(GS)and to 91.59%(GL),respectively,among the three samples.The antioxidant capability and the total phenolic contents of G.rutilus were evaluated in this study.The highest total phenolic content(TPC)of 192.23 mg GAE/g was found in GL,which differed significantly(P<0.05)from the latter two samples,whereas the lowest value of 156.11 mg GAE/g was found in GW.ABTS radical cation scavenging activity,FRAP ferric reducing antioxidant capacity(FRAP)radical scavenging activity,and oxygen radical absorbance capacity(ORAC)were investigated to screen the antioxidant properties of extracts.The contents of total phenolic compounds and their antioxidant capacities in vitro showed significant correlations(P<0.01).Among the three types of samples,the phenolic compounds of GL exhibited the highest antioxidant capacity,showing the values of 0.089 mM TE/g for ABTS,0.949 mM Fe^2+E/g for FRAP,and 1.952 M TE/g for ORAC.However,regarding the total antioxidant capacity,GS exhibited the highest antioxidant capacity,showing the values of 0.002648 mM TE/g for ABTS,0.004437 mM Fe^2+E/g for FRAP,and 0.256μM TE/g for ORAC.In conclusion,HS-SPME was more suitable for the extraction of volatile aroma components from G.rutilus.GL had the most abundant aroma components.GL had the highest TPC and antioxidant capacity compared with those of GS and GW,whereas GS showed the opposite results.Interestingly,GS was found to have the highest total antioxidant capacity in vitro.Based on these measured indicators,worm infection had no negative effect on the quality of G.rutilus.Therefore,worm-infected G.rutilus can also be consumed by humans.

Evaluation of Antioxidants, Total Phenolics and Antimicrobial Activities of Ethyl Acetate Extracts From Fungi Grown on Rice Straw

Rice straw(RS)collected from Egyptian agricultural environment(Al-Masied village-Alsharqia Governorate-Egypt)was used as substrate for three fungal isolates namely:4b,1Asp,Pleurotus ostreatus NRRL 3501 and mixed culture of(4b,1Asp).Isolates number 4b and 1Asp were identified using the molecular technique(18S rRNA).Isolate 4b and 1Asp,were identified as Trichoderma saturnisporum MN1-EGY and Aspergillus niger MN2-EGY,respectively.Trichoderma saturnisporum MN1-EGY extract exhibited the highest antimicrobial activity compared to the other fungal extracts.Total phenolic,antimicrobial and antioxidant activities were also determined from the ethyl acetate extract of rice straw inoculated by these fungi.The antioxidant scavenging concentration(SC50)values of the tested samples were 88.84,91.45,94.65 and 100.0μg/ml,respectively for Pleurotus sp.,Aspergiluus niger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.,after 15 days incubation,compared to ascorbic acid as positive control with SC50 value equal to 8.0μg/ml.Total phenolic contents(TPCs)were maximum in Pleurotus sp.extract and found to be the most polyphenolic enriched sample(380.64 mg GAE/g dry extract)compared to extracts of Aspergiluusniger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.(261.89,198.52,and 119.80 mg GAE/g dry extract),respectively.The GC-MS analysis has been also performed for the promising extracts.

Phytochemical Screening, Total Phenolic and Antioxidant Activity of Numerous Extracts from Leaves and Bark of <i>Bauhinia rufescens</i>Lam

Researches for natural antioxidants that play an important role in the prevention of diseases linked to free radicals have increased in recent years. In this study, antioxidant activity of Bauhinia rufescens Lam which is a medicinal plant was investigated. The methanol extract, acetone extract and water extract of leaf and trunk bark had antioxidant activity. Three methods were used: 2,2-diphenyl-1picryl-hydrazyl (DPPH), 2,2’-Azino-bis-(3-ethylbenzoth iazoline-6-sulfonic acid) (ABTS) and ferric ion reducing power (FRAP) by spectrophotometry. Phytochemical screening was carried out followed by the quantification of the total phenolic by the Folin-Ciocalteu method. The analysis of variance (ANOVA) with the STATISTICA 7.1 software revealed significant differences (p < 0.05). Percentage inhibition (PI) and IC50 of the extracts were obtained using the OriginPro 8.5 software. These tests show that the bark is as rich in total phenolic as the leaves. The DPPH test shows that at 2.5 mg/ml, the bark and the leave have similar activity. Bark has a percentage inhibition (PI) of 86.55% ± 0.026% compared to the leave which PI is 85.63% ± 0.02%. As for the ABTS test, the bark extract reached its maximum activity at 2.5 mg/ml with a PI of 99.81% ± 0.012% compared to the leaf extract which has a PI of 99.61% ± 0.025%. The best IC50 of the extracts obtained with the DPPH radical is 0.139 ± 0.001 mg/ml (hydro-acetonic), 0.354 ± 0.001 mg/ml (hydromethanolic) and 0.840 ± 0.001 mg/ml (aqueous) on the bark. With ABTS test, it was obtained 0.351 ± 0.001 mg/ml (hydro-acetone;bark), 0.403 ± 0.001 mg/ml (hydro-acetone;leaves) and 0.474 ± 0.001 mg/ml (aqueous;bark). The reducing power of the leaves is slightly higher than that of the bark. Standard of ascorbic acid, has a PI of 94.86 ± 0.008% with an IC50 of 0.213 ± 0.001 mg/ml. Thus, it is easy to conclude that the bark of Bauhinia rufescens has a better activity than the leaves and the alcoholic extracts have given better results than the aqueous extract.

Estimation of Total Phenolic Compounds and Non-Targeted Volatile Metabolomics in Leaf Tissues of American Chestnut (<i>Castanea dentata</i>), Chinese Chestnut (<i>Castanea mollissima</i>) and the Backcross Breeding Generations

The American chestnut (Castanea dentata) was once a dominant tree species in the Appalachian Mountains and played a critical role in the ecological system. However, it was nearly eliminated by chestnut blight caused by the Ascomycetous fungus Cryphonectria parasitica. Identification of compounds specific to species and backcross hybrids may help further refine disease resistance breeding and testing. Phenolic compounds produced by plants are significant to their defense mechanisms against fungal pathogens. Therefore, an analytical platform has been developed to estimate the total phenolic content in leaf tissues of the American chestnut, Chinese chestnut (Castanea mollissima), and their backcross breeding generations (B3F2 and B3F3) using the Folin-Ciocalteu reagent assay with UV/Vis spectrophotometry which may be used to predict blight resistance. Adsorption (765 nm) results from leaf tissue extraction in methanol/water (95%:5% v/v) and pH 2, show that the variations among these four tree species are significant (ANOVA p = 2.3 × 10-7). The kinetics of phenolic compound solid-liquid extraction was elaborated using Peleg, second order, Elovich, and power law models. In addition, extensive analysis using headspace solid phase microextraction (SPME) gas chromatography and mass spectrometry was conducted to identify volatile organic compounds (VOCs) from the leaf of American chestnut, Chinese chestnut, and their backcross hybrids B3F2 and B3F3. A total of 67 VOCs were identified among all chestnut types. Many of the metabolites associated with the Chinese chestnut have been reported to have antifungal properties, whereas the native and hybrid American chestnut metabolites have not. Most of the antifungal metabolites showed the strongest efficacy towards the Ascomycota phylum. A partial least squares discriminant analysis (PLS-DA) model (R2X = 0.884, R2Y = 0.917, Q2 = 0.584) differentiated chestnut species and hybrids within the first five principal component (PCs).

Comparison of Total Phenolic Content and Total Antioxidant Activity in Local Red Wines Determined by Spectrophotometric Methods

In this study, the antioxidant activity of local red wines was determined by four different analytical methods: 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS?+) radical cation decolourisation, ferric reducing/antioxidants power (FRAP) and cupric ion reducing capacity in the presence of neocuproine (CUPRAC) for the evaluation of reducing power (PR). They were correlated with the total phenolic content (TPC) determined with the Folin-Ciocalteu’s reagent using gallic acid as a standard. The total polyphenol concentration was found to vary from 2599.90 to 4846.57 mg/L gallic acid equivalents (GAE). The total antioxidant activity determined by DPPH, ABTS, FRAP and CUPRAC methods was found to vary from 7.49 - 15.93 mmol/L, 12.02 - 24.73 mmol/L, 12.65 - 27.68 mmol/L and 13.19 - 31.07 mmol/L, respectively. The total phenolic contents of red wine samples exhibited a good correlation (p < 0.01) with antioxidant properties.

In vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah

Objective:To detect the in vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.Methods:The dry powder leaves of Tetrastigma were extracted with different organic solvent such as hexane.ethyl acetate,chloroform,butanol and aqueous methanol.The total phenolic and total flavonoids contents of the essential oil and various organic extracts such as hexane,ethyl acetate,chloroform,butanol and aqueous ethanol were determined by Folin-Ciocalteu method and the assayed antioxidant activity was determined in vitro models such as antioxidant capacity by radical scavenging activity usingα,α-diphenyl-β-picrylhydrazyl (DPPH) method.Results:The total phenolic contents of the essential oil and different extracts as gallic acid equivalents were found to be highest in methanol extract(386.22 mg/g) followed by ethyl acetate(190.89 mg/g).chloroform(175.89 mg/g).hexane(173.44 mg/g).and Imtanol extract (131.72 mg/g) and the phenolic contents not detected in essential oil.The antioxidant capacity of the essential oil and different extracts as ascorbic acid standard was in the order of methanol extract】ethyl acetate extract】chloroform】butanol】hexane extract also the antioxidant activity was not detected in essential oil.Conclusions:The findings show that the extent of antioxidant activity of the essential oil and all extracts are in accordance with the amount of phenolics present in that extract.Leaves of Tetrastigma being rich in phenolics may provide a good source of antioxidant.

Total phenolic, flavonoid content, and antioxidant activity of flour, noodles, and steamed bread made from different colored wheat grains by three milling methods

The objective of this study was to evaluate the effects of wheat variety, food processing, and milling method on antioxidant properties. Black wheat variety Heibaoshi 1 had the highest total phenolic content(659.8 μg gallic acid equivalents g-1), total flavonoid content(319.3 μg rutin equivalents g-1), and antioxidant activity, whereas light purple wheat variety Shandongzimai 1 had the lowest total flavonoid content(236.2 μg rutin equivalents g-1) and antioxidant activity. Whole wheat flour and partially debranned grain flour had significantly higher total phenolic contents, total flavonoid contents, and antioxidant activity than refined flour(P < 0.05). Compared with flour, total phenolic contents, total flavonoid contents and antioxidant activity decreased in noodles and steamed bread, whereas noodles had slightly higher total phenolic and flavonoid content than steamed bread. Antioxidant activities(by ferric reducing ability of plasma assay) of steamed bread made from whole wheat flour, partially debranned grain flour, and refined flour were 23.5%, 21.1%, and 31.6% lower, respectively, than the corresponding values of flour. These results suggested that black whole wheat flour and partially debranned grain flour are beneficial to human health.

Estimation of total phenolic content,in-vitro antioxidant and anti-inflammatory activity of flowers of Moringa oleifera

Objective:To evaluate and compare the antioxidant potential and anti-inflammatory activity of ethanolic extract of flowers of Moringa oleifera(M.oleifera)grown in Oman.Methods:Flowers of M.oleiferawere collected in the month of December 2012 and identified by a botanist.Alcoholic extract of the dry pulverized flowers ofM.oleiferawere obtained by cold maceration method.The ethanolic flower extract was subjected to preliminary phytochemical screening as the reported methods.Folin-Ciocalteu reagent was used to estimate total phenolic content.DPPH was used to determinein-vitroantioxidant activity and anti-inflammatory activity of flowers was investigated by protein denaturation method.Results:Phytochemical analysis of extract showed presence of major classes of phytochemicals such as tannins,alkaloids,flavonoids,cardiac glycosidesetc.M.oleiferaflowers were found to contain 19.31 mg/g of gallic acid equivalent of total phenolics in dry extract but exhibited moderate antioxidant activity.The anti-inflammatory activity of plant extract was significant and comparable with the standard drug diclofenac sodium.Conclusions:The results of our study suggest that flowers ofM.oleiferapossess potent anti-inflammatory activity and are also a good source of natural antioxidants.Further study is needed to identify the chemical compounds responsible for their anti-inflammatory activity.

Measurement of total phenolic content and antioxidant activity of aerial parts of medicinal plant Coronopus didymus

Objective: To evaluate the total phenolic content and compare the antioxidant activity of various solvent extracts and fractions from the aerial parts of Coronopus didymus through various assays. Methods: Total phenolic content was determined using the Folin-Ciocalteu assay and the in vitro antioxidant activity of a number of different extracts was investigated in a dose-dependent manner with three different methods: the 2,2-diphenyl-1-picrylhydrazyl(DPPH), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt(ABTS) and ferric reducing antioxidant power(FRAP) assays. A flavone was isolated from the most active ethanolic extract with high antioxidant activity using size exclusion chromatography. IC_(50) values were calculated for the DPPH and ABTS methods. The FRAP activity was assessed in terms of μM Fe(II) equivalent. Results: The phenolic content was found to be highest in the ethanol extract(CDA Et; 47.8 mM GAE) and the lowest in the dichloromethane extract(CDA DCM; 3.13 mM GAE). The ethanol extract showed high radical scavenging activity towards DPPH and ABTS radicals with IC_(50) values of(7.80 × 10~2) and(4.32 × 10~2) μg/m L, respectively. The most active ethanol extract had a FRAP value of 1 921.7 μM Fe(Ⅱ) equivalent. The isolated flavone F10C(5,7,4'-trihydroxy-3'-methoxy flavone) was far more effective for scavenging free radicals in the DPPH and ABTS assays with IC_(50) of 43.8 and 0.08 μg/m L, than the standard trolox, with IC_(50) values of 97.5 and 21.1 μg/m L, respectively. In addition, the flavone F10C and the standard ascorbic acid had FRAP values of 1 621.7 and 16 038.0 μM Fe(Ⅱ) equivalents, respectively. Conclusions: The total phenolic content of extracts in decreasing order is ethanol extract(CDA Et)> acetone extract(CDA ACE)> phenolic extract(CDA MW)> n-hexane extract(CDA nHX)> chloroform extract(CDA CHL)> dichloromethane extract(CDA DCM). The ordering of extracts in terms of antioxidant activity from highest to lowest is CDA Et> CDA MW> CDA DCM> CDA CHL> CDA ACE> CDA nHX in DPPH, ABTS and FRAP assays. A significant relationship is found between antioxidant potential and total phenolic content, suggesting that phenolic compounds are the major contributors to the antioxidant activity of Coronopus didymus.

GC-MS analysis,determination of total phenolics,flavonoid content and free radical scavenging activities of various crude extracts of Moringa peregrina(Forssk.) Fiori leaves

Objective:To perform phytochemical screening,estimate total phenolics,flavonoids and to evaluate antioxidant potential of Moringa peregrina(M.peregrina) leaves.Methods:The dried powdered leaves of M.peregrina(150 g) were extracted exhaustively by Soxhlet with ethanol and then fractionated into hexane,chloroform,ethy alacetate and methanol.All the prepared extracts were also analyzed by gas chromatography-mass spectrometry to identify and characterize the chemical compounds present in the crude extracts.Folin- Ciocalteu reagent and aluminium chloride colorimetric methods were used to estimate total phenolic and flavonoid content of extracts.Hydrogen peroxide and 1,1 diphenyl-2-picrylhydrazyl were used to determine in vitro antioxidant activity.Results:Phytochemical analysis of ethanol extract showed presence of major classes of phytochemicals.Gas chromatography-mass spectrometry results revealed presence of 19 phytoconstituents in hexane extract,6 in ethyl acetate and 7 compounds in methanolic extract.Methanol extract was found to contain the highest phenolic content and flavonoids.In vitro antioxidant activities of all crude extracts were significant and comparable with the standard ascorbic acid.Conclusions:Results of this study show that the leaves of M.peregrina are the rich source of phenolic compounds that can play an important role in preventing the progression of many diseases.

Total Phenolic Content and Antioxidant Activity of Red and Yellow Quinoa (<i>Chenopodium quinoa</i>Willd.) Seeds as Affected by Baking and Cooking Conditions

Seeds with colored testa (seed coat) contain high concentrations of polyphenolic compounds that exhibit high levels of antioxidant activity. Common processing procedures, such as cooking and baking, decrease the levels of these bioactive compounds and consequently, overall antioxidant activity. Here, the effects of baking and cooking processes were examined on total phenolic content (TPC), total flavonoid content (TFC) and ferric-reducing ability of plasma antioxidant activity (FRAP AA) of red and yellow quinoa seeds. Our results indicate that red quinoa seed contains significantly higher levels of TPC, TFC and FRAP AA than yellow quinoa seeds. In addition, cooked and baked quinoa seeds retain most of their TPC, TFC and FRAP AA in the final product. Thus, red quinoa seeds processed by these two methods might be considered a functional food, in addition to its traditional role of providing dietary proteins. Due to their high antioxidant activity, red quinoa seeds might also contribute significantly to the management and/or prevention of degenerative diseases associated with free radical damage.

Study of total phenol,flavonoids contents and phytochemical screening of various leaves crude extracts of locally grown Thymus vulgaris

Objective:To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol,flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al Jabal Al Akhdar,Nizwa.Sultanate of Oman.Methods:The leave sample was extracted with methanol and evaporated.Then it was defatted with water and extracted with different polarities organic solvents with increasing polarities.The prepare hexane,chloroform,ethyl acetate,hutanol and methanol crude extracts were used for their evaluation of total phenol,flavonoids contents and phytochemical screening study.The established conventional metliods were used for quantitative determination of total phenol,flavonoids contents and phytochemical screening.Results:Phytochemical screening for various crude extracts were tested and shown positive result for flavonoids,saponins and steroids compounds.The result for total phenol content was the highest in hutanol and the lowest in methanol crude extract whereas the total flavonoids contents was the highest in methanol and the lowest hexane crude extract.Conclusions:The crude extracts from locally grown Thymus vulgaris showed high concentration of flavonoids and it could be used as antibiotics for different curable and uncurable diseases.

Total Phenolic Content and Antioxidant Activity of Chickpea (<i>Cicer</i><i>arietinum</i>L.) as Affected by Soaking and Cooking Conditions

Chickpea lines with colored testa (seed coat) contain high levels of polyphenolic compounds that exhibit high levels of antioxidant activity. However, common processing procedures, such as soaking and cooking, may decrease the levels of these bioactive compounds and subsequent overall antioxidant activity. Here, the effects of soaking, cooking and steaming processes were examined in relation to total phenolic content (TPC), total flavonoid content (TFC) and ferric reducing ability of plasma antioxidant activity (FRAP AA) of colored chickpea seeds. All processing steps significantly reduced TPC, TFC and FRAP AA in all of the tested chickpea seeds. Nevertheless, soaking the seeds at room temperature (for 22 h) resulted in a smaller decrease in TPC, TFC and FRAP AA than soaking at 60℃ (for 2 h). Moreover, steaming was superior to cooking in terms of conserving polyphenol and antioxidant activity. The observed reduction in TPC was mainly due to leaching of these compounds from the seed coat into the soaking or cooking water. Based on these results, we suggest that soaking at room temperature for 22 h followed by steaming for 1 h is the best method for retaining TPC, TFC and FRAP AA of colored chickpea.

Effect of Gamma Irradiation on Total Phenolic Content and <i>in Vitro</i>Antioxidant Activity of Pomegranate (<i>Punica granatum</i>L.) Peels

Pomegranate peels were studied for the effect of gamma irradiation on microbial decontamination along with its effect on total phenolic content and in vitro antioxidant activity. Gamma irradiation was applied at various dose levels (5.0, 10.0, 15.0 and 25.0 kGy) on pomegranate peel powder. Both the values of total phenolic content and in vitro antioxi- dant activity were positively correlated and showed a significant increase (p < 0.05) for 10.0 kGy irradiated dose level immediately after irradiation and 60 days of post irradiation storage. At 5.0 kGy and above dose level, gamma irradia- tion has reduced microbial count of pomegranate peel powder to nil. Post irradiation storage studies also showed that, the irradiated peel powder was microbiologically safe even after 90 days of storage period.

Study on Polyphenol Oxidase Activity and Total Phenol Content of Docynia indica

[Objectives] To study the polyphenol oxidase (PPO) activity and total phenol content of Docynia indica .[Methods] The tender branches and petioles of the medicinal and edible plant D. indica were used as experimental materials, and the annual changes of total phenol content and polyphenol oxidase (PPO) activity were analyzed.[Results] pH 7.0 was the optimum value of polyphenol oxidase activity in D. indica plants;the best substrate was catechol with the concentration of 0.15 mol/L;the optimum temperature was 25 ℃.[Conclusions] The total phenol content of D. indica plants was the lowest in April, May and September of each year. The polyphenol oxidase activity of D. indica plants at flowering and fruiting stage was significantly higher than that at pre-flowering stage.