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.

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.

Protein and Phenolic Contents and Antioxidant Activities of 14 Early Maturing Potatoes as Affected by Processing

The effects of processing and genotype (fourteen early potato varieties) were evaluated for their phytochemicals, total phenolics (TPC), total flavonoids (TFC), total anthocyanins (TAC), antioxidant activities measured by ORAC, FRAP and DPPH assays and protein content. While all these profiles were highly dependent on the potato variety and processing, F09085, F10090, French Fingerlings, Purple Fiesta, Red Thumb, Ciklamen and Norland were identified as nutritionally rich in phytochemicals such as TPC, TFC, TAC, higher antioxidant capacities and protein (p p p < 0.0001).

Antioxidant Activity and Phenolic Content of Okoubaka aubrevillei (Anunuebe) Fruit Pychnobotrya nitida (Osu) Leaf Extracts

The antioxidant activity and the total phenolic content of Okoubaka aubrevillei(Anunuebe)and Pychnobotrya nitida(Osu)plant extracts were investigated in this study to justify their ethno medicinal importance.The antioxidant activity of crude extracts of both plants was investigated using the scavenging effect on DPPH(2,2-Diphenyl-1-Picrylhydrazyl Radical)assay,while the total phenolic content was determined by the Folin-Ciocalteu reagent method.When compared to standard drug vitamin C at various concentrations,both extracts exhibited potent antioxidant activity that increased with increasing concentration of extracts.The high positive linear correlation between the antioxidant capacity and the total phenolic content suggests that the antioxidant capacity of both plants can be largely attributed to their phenolic compounds.Based on these findings,O.aubrevillei fruit and P.nitida leaf could be potential natural antioxidant sources for preventing free radical-induced diseases.

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.

Antioxidant,antimicrobial and total phenolic contents of Calophyllum symingtonianum

Objective:To determine the total phenolic content,antioxidant and antimicrobial activities of the extracts from Calophyllum symingtonianum.Methods:The extracts were tested for their antioxidant activity by the DPPH radical scavenging assay and the β-carotene bleaching assay,while the antimicrobial activity was determined by disc diffusion method.Results:All the tested extracts showed antioxidant and antimicrobial properties.The extracts showed moderate antimicrobial activity against Staphylococcus aureus with zone of inhibition values of 10,11 and 12 mm for n-hexane,dichloromethane and methanol extracts respectively at 30μg/disc.N-hexane showed low antimicrobial activity against Pseudomonas aeruginosa(5 mm)at 30μg/disc.The total phenolic test showed that methanol has high phenolic content(162.25 mg GAE/g of extract)compared to the other extracts.Conclusions:The ability of the extracts to inhibit microbial growth at a concentration of 30μg/disc indicated the its potent antimicrobial activity.

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

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.

Phenolic Profiles and Antioxidant Activity of Buckwheat (Fagopyrum esculentum Mench and Fagopyrum tartaricum L. Gaerth) Hulls, Brans and Flours

The extracts from hulls, brans and flours of Fagopyrum esculentum M6ench （FEM, three varieties） and Fagopyrum tartaricum L. Gaerth （FTG, seven varieties） were screened for free and bound phenolic content or total phenolic content （TPC）, as well as 1,1 diphenyl-2-picryl hydrazyl （DPPH） free radical scavenging activity and reducing power. Free phenolics were predominant in buckwheat hulls, brans and flours. FEM hulls extract exhibited the highest reducing power and DPPH free radical scavenging activity with the average ECs0 84.54 μg mL^-1 and IC50 11.54 μg mL^-1 respectively, FTG brans extract had the highest average TPC （24.87 mg GAE g^-1 DW）, and FEM flours extract showed the lowest TPC, reducing power and radical scavenging activity. Furthermore, the correlations among TPC, DPPH free radical scavenging activity and reducing power of all the samples were investigated. The rank correlation coefficient （rs） between reducing power and DPPH free radical scavenging activity of buckwheat hulls, between TPC and DPPH free radical scavenging activity of buckwheat flours were 0.76 and 0.79, respectively （P〈0.05）. However, there is no significant correlation between the remaining indexes of hulls and flours, as well as the ten buckwheat brans. This result indicated that some non-phenolic compounds also contributed to the total antioxidant activity in hulls, brans and flours of buckwheats. This study demonstrated that buckwheat hulls and brans, rather than flours, are good source of antioxidants.

Diversity of Antioxidant Content and Its Relationship to Grain Color and Morphological Characteristics in Winter Wheat Grains

The current interest in the health beneifts of whole wheat grain has prompted breeders to further increase the concentration of antioxidants in wheat. The objective of this study was to investigate the variation in antioxidant content among Chinese wheat grains and the relationship between antioxidants and grain color and morphological characteristics. A wide variation was observed in the total phenolic, carotenoid and lfavonoid contents, as well as the antioxidant activity （AOA）, of Chinese wheat varieties. Black wheat had the highest mean total phenolic, carotenoid and lfavonoid contents and the highest AOA, followed by red and white wheats. The grain color parameters were signiifcantly negatively correlated with total phenolic, carotenoid and lfavonoid contents and AOA among all of the wheat varieties examined, and grain weight was also signiifcantly negatively correlated with these traits. The same correlation between grain weight and antioxidant traits was also observed within individual groups of wheat, which indicates that grain weight may be used as an index for selecting wheat varieties with high AOA. Landraces had signiifcantly higher lfavonoid content than commercial wheat varieties. The results of this study may be useful for breeding nutrient-rich wheat varieties.

Transcriptional proffling between yellow-and black-seeded Brassica napus reveals molecular modulations on flavonoid and fatty acid content

Brassica napus is an important cash crop broadly grown for the vegetable and oil values.Yellow-seeded B.napus is preferred by breeders due to its improved oil and protein quality,less pigments and lignin compared with the blackseeded counterpart.This study compared the differences in flavonoid and fatty acid contents between yellow rapeseed from the progenies of B.napus-Sinapis alba somatic hybrids and the black-seeded counterpart using RNA-seq analysis.Through HPLC-PDA-ESI(-)/MSanalysis,it was found that phenylpropanoids and flavonoids(i.e.,isorhamnetin,epicatechin,kaempferol,and other derivatives)in yellow seed were significantly lower than those in black seed.The fatty acid(FA)content in yellow rapeseed was higher than that in black rapeseed due to the variation of C16:0,C18:0,C18:1,C18:2,and C18:3 contents.RNA-seq analysis of seeds at four and five weeks after flowering(WAF)indicated that differentially expressed genes(DEGs)between black and yellow rapeseeds were enriched in flavonoid and FA biosynthesis,including BnTT3,BnTT4,BnTT18,and BnFAD2.Also,genes related to FA biosynthesis,desaturation and elongation(FAD3,LEC1,FUS3,and LPAT2)in yellow seed were up-regulated compared to those in black seed,while genes involved in beta-oxidation cycle(AIM1 and KAT2)of yellow seed were down-regulated compared to those in black seed.The DEGs related to the variation of flavonoids,phenylpropanoids,and FAs would help improve the knowledge of yellow seed character in B.napus and promote rapeseed improvement.

Responses of Photosynthetic Pigment, Phenol and Total Saponin Contents of Panax notoginseng to Supplemental UV-B under Field Conditions

[Objective] The aim of this study was to investigate the content changes and their correlations of the photosynthetic pigment,phenols,including total phenols,total flavonoids and anthocyanins,and total saponins of the one-year-old P.notoginseng plants under supplemental UV-B stress in fields.[Method] The one-year-old plants were irradiated by UV-B in field for 1 min per day,and the plants under the UV-B lamp were regarded as a circle center,achieving an annular leaf-sampling.The photosynthetic pigment,phenols and total saponins of the leaves were determined spectrophotometrically.[Result] With the increase of sampling radius,the supplemental UV-B intensity decreased significantly,the contents of chlorophyll （Chl） a,Chl b,Chl （a＋b）,carotenoid （Car） and total photosynthetic pigment （Chl＋Car） of the leaves increased extremely significantly,the Chl a/b and total phenol content （TPC） decreased extremely significantly,but the Chl （a＋b）/Car changes were not significant.The contents of total flavonoids,anthocyanins and saponins all increased due to the increasing of UV-B,displaying dose effects.The UV-B intensity was positively correlated with the Chl a/b,and negatively with the Chl a,Chl b,Chl （a＋ b）,Car and （Chl＋Car） contents; and the two of TPC,total flavonoid content （TFC）,total anthocyanin content （TAC） and total saponin content （TSC） were positively correlated,all reaching extremely significant level.The UV-B intensity was positively and significantly correlated with the total flavonoid content （TFC）,negatively and significantly with the Chl （a＋b）/Car,and positively and insignificantly with the TPC,TAC and TSC.[Conclusion] For one-year-old plants of P.notoginseng,UV-B can decrease the contents of the Chl a,Chl b,Chl （a＋b）,Car and （Chl＋Car） and increase the Chl a/b and TPC,and,furthermore,induce the increases of the TFC,TAC and TSC in a dose-dependent manner.However,UV-B can hardly change the Chl （a＋b）/Car.The supplemental UV-B of well-suited dose might be one of the effective measures to improve the TSC of P.notoginseng.

Comparative assessment of total polyphenols, antioxidant and antimicrobial activity of different tea varieties of Bangladesh

Objective: To determine the total polyphenol content, antioxidant activity and antibacterial properties of the extracts of different Bangladeshi tea varieties such as flowery broken orange pekoe, broken orange pekoe, red dust and green tea.Methods: Total phenolic and flavonoid contents were determined by Folin–Ciocalteu and aluminum chloride colorimetric assay, respectively.The antioxidant capacity was determined by ferric ion reducing antioxidant power and phosphomolybdenum method.Antibacterial activity was evaluated by disc diffusion method in agar plate and subsequently, the minimum inhibitory concentration was determined by broth dilution method.Results: Total phenolic and flavonoid contents were significantly higher(P < 0.05) in green tea compared to other three black tea varieties.The green tea also showed a higher free radical scavenging and antioxidant activities than all the other tea varieties tested(P < 0.05).In addition, the extracts of all four tea varieties showed inhibitory activity against several pathogenic bacteria and also the same trend of higher antimicrobial activity of green tea than other tea varieties was observed.Conclusions: Taken together, the results of this study demonstrated that Bangladeshi tea,especially the green tea, may act as a substitute for natural antioxidants and as a promising antibacterial agent for beneficial influence in human health.

Fruit Yield and Quality, and Irrigation Water Use Efficiency of Summer Squash Drip-Irrigated with Different Irrigation Quantities in a Semi-Arid Agricultural Area

Fruit yield, yield components, fruit mineral content, total phenolic content, antioxidant activity and irrigation water use efifciency （IWUE） of summer squash responses to different irrigation quantities were evaluated with a ifeld study. Irrigations were done when the total evaporated water from a Class A pan was about 30 mm. Different irrigation quantities were adjusted using three different plant-pan coefifcients （Kcp, 100% （Kcp1）, 85% （Kcp2） and 70% （Kcp3））. Results indicated that lower irrigation quantities provided statistically lower yield and yield components. The highest seasonal fruit yield （80.0 t ha-1） was determined in the Kcp1 treatment, which applied the highest volume of irrigation water （452.9 mm）. The highest early fruit yield, average fruit weight and fruit diameter, length and number per plant were also determined in the Kcp1 treatment, with values of 7.25 t ha-1, 264.1 g, 5.49 cm, 19.95 cm and 10.92, respectively. Although the IWUE value was the highest in the Kcp1 treatment （176.6 kg ha-1 mm-1）, it was statistically similar to the value for Kcp3 treatment （157.1 kg ha-1 mm-1）. Total phenolic content and antioxidant activity of fruits was higher in the Kcp1 （44.27 μg gallic acid equivalents （GAE） mg-1 fresh sample） and in the Kcp2 （84.75%） treatments, respectively. Major （Na, N, P, K, Ca, Mg and S） and trace （Fe, Cu, Mn, Zn and B） mineral contents of squash fruits were the highest in the Kcp2 treatment, with the exception of P, Ca and Cu. Mineral contents and total phenolic content were signiifcantly affected by irrigation quantities, but antioxidant activity was not affected. It can be concluded that the Kcp1 treatment was the most suitable for achieving higher yield and IWUE. However, the Kcp2 treatment will be the most suitable due to the high fruit quality and relatively high yield in water shortage conditions.

A pilot study of antioxidant potential of endophytic fungi from some Sudanese medicinal plants

Objective: To evaluate the total phenolic content and total antioxidant capacity of ethyl acetate extracts of 21 endophytic fungi isolated from five Sudanese medicinal plants: Calotropis procera, Catharanthus roseus, Euphorbia prostrate, Vernonia amygdalina and Trigonella foenumgraecum. Methods: Crude extracts of endophytic fungi and their host plants were tested by classical Folin-Ciocalteu colorimetric method to determine the total phenolic content, also total antioxidant capacity was estimated using 1,1-diphenyl-2-picrylhydrazyl free radical scavenging in vitro method. Results: Among the endophytes, endophytic fungus Aspergillus sp. from Trigonella foenum-graecum seeds demonstrated the highest both total phenolic content in term of gallic acid equivalent(GAE) [(89.9±7.1 mg GAE/g)] and antioxidant activity for 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay [IC50:(18.0±0.1 μg/m L)]. A high positive linear correlation(R2=0.999 1) was found between total antioxidant capacity and total phenolic content of endophytic fungi isolated from Vernonia amygdalina. Conclusions: The present study revealed that some endophytic fungi from the five Sudanese medicinal plants could be a potential source of novel natural antioxidant compounds.

Antioxidant Activities of Nine Selected Culinary Spices from China

The antioxidant activities and the total phenolic contents of the water and/or ethanol extracts of the nine selected culinary spices from China were systematically investigated. Both ethanol extracts and water extracts had high ability of 1, 1-diphenyl-2-picrylhydrazyl（DPPH） radical scavenging, 2, 2＇-azinobis（3-ethylbenzthiazoline-6-sulphonic acid）（ABTS） radical scavenging and ferric reducing antioxidant power（FRAP）. The ethanol extract of Sichuan pepper showed the highest ability of DPPH radical scavenging. The extract with the highest ABTS radical scavenging effect was that of ethanol extract of cinnamon. Both ethanol and water extracts of cinnamon possessed the high ferric reducing antioxidant power（FRAP） with the values of 4 541.87 and 1 134.52 μmol of Fe（Ⅱ）/g. The extracts with high hydroxyl radical-mediated deoxyribose degradation were all the ethanol extracts as follows： cinnamon, bay leaf, Sichuan pepper, star anise and fennel. The extracts with high antioxidant activities also had the high contents of the phenols. The study indicated that these spices might be potentially be used as natural antioxidants in food.

Comparative analysis of antioxidant activities of essential oils and extracts of fennel(Foeniculum vulgare Mill.)seeds from Egypt and China

The present study was conducted to assay the antioxidant activities of essential oils and ethanol extracts of fennel(Foeniculum vulgare Mill.)seeds from Egypt and China.The major components of the Egyptian fennel essential oil were estragole(51.04%),limonene(11.45%),l-fenchone(8.19%)and trans-anethole(3.62%)by GC–MS analysis.Whereas,the major constituents of Chinese fennel essential oil were transanethole(54.26%),estragole(20.25%),l-fenchone(7.36%)and limonene(2.41%).The fennel seed extracts from Egypt and China contained appreciable levels of total phenolic contents(42.24 and 30.94 mg PE/g,respectively).The extracts exhibited good DPPH radical scavenging capacity with IC50(6.34 and 7.17 mg/g),respectively.A high variation in free radical scavenging activities of essential oils was observed.The Chinese fennel essential oil showed high activity in DPPH radical scavenging with IC50(15.66 mg/g).The Egyptian fennel essential oil showed very low activity with IC50(141.82 mg/g).The results of the present investigation demonstrated significant variations in the antioxidant activities of fennel essential oils and extracts from Egypt and China.

Seasonal variation and ecological importance of tannin and nutrient concentrations in Casuarina equisetifolia branchlets and fine roots

In this study,we investigated the effects of environmental factors on plant phenolic variability,seasonal dynamics of total phenolic content(TP),extractable condensed tannins(ECT),protein-bound condensed tannins(PBCT),fiber-bound condensed tannins(FBCT),total condensed tannins(TCT),protein precipitation capacity(PPC)and nutrient content in the branchlets and fine roots of Casuarina equisetifolia.TP and TCT concentrations in branchlets were lowest in the spring,then increased in summer and autumn,similar to the seasonal dynamics in air temperature.TP and TCT concentrations in fine roots were highest in summer,coinciding with heavy precipitation.In general,TP and TCT concentrations were higher in branchlets than in fine roots.No significant difference was found in C concentration among various seasons for either branchlets or fine roots.Branchlets had significantly higher N and P concentrations than fine roots in most seasons.The C/N and N/P ratios in branchlets were significantly lower than in fine roots in all seasons,except summer.The relationship between branchlets and fine roots was significant for C,P and FBCT,but no significant relationships were found for N,TP,ECT,PBCT and TCT.Additionally,TP and TCT content were each significantly correlated with PPC in branchlets and in fine roots.Both TP/N and TCT/N ratios were highest in the autumn for the branchlets and in the summer for fine roots.The results indicate that high temperatures lead to increased tannin production in branchlets,but that the tannin content in fine roots is mainly affected by precipitation.Tannin content was greater in branchlets than in fine roots,which may indicate that selective pressure is greater on branchlets than on fine roots.

Comparison of Antioxidant and Antimicrobial Activities of Acetone and Water Extracts of <i>Theobroma cacao</i>Beans

This present study compared antioxidant and antimicrobial activities of acetone and water extracts of Theobroma cacao beans against Escherichia coli. Total phenolic content (TPC) in both extracts was estimated by the Folin-Denis reagent. The present study showed that the 70% (v/v) acetone extract had a higher extraction yield and TPC (37% and 109 mg TAE g-1 dry weight) than the water extract (33% and 76 mg TAE g-1 dry weight). The antioxidant activities of both extracts were estimated by the DPPH Scavenging Assay. The extract obtained using 70% (v/v) acetone showed higher antioxidant activity (54%) compared to the antioxidant activity obtained using water (34%). Antimicrobial activities of acetone and water extracts from Theobroma cacao were measured against Escherichia coli and were screened by agar well diffusion method and further confirmed with the disc diffusion method. The bacterial growth was measured in Mueller Hinton agar. The extracts inhibited the growth of the Escherichia coli cultured, and the acetone extracts showed antimicrobial capacity comparable or equivalent, as seen in commercial ampicillin.

Polyphenols in Fruits and Vegetables and Its Effect on Human Health

Polyphenols represent a group of chemical substances common in plants, structurally characterized by the presence of one or more phenol units. Polyphenols are the most abundant antioxidants in human diets and the largest and best studied class of polyphenols is flavonoids, which include several thousand compounds. Numerous studies confirm that they exert a protective action on human health and are key components of a healthy and balanced diet. Epidemiological studies correlate flavonoid intake with a reduced incidence of chronic diseases, such as cardiovascular disease, diabetes and cancer. The involvement of reactive oxygen species (ROS) in the etiology of these degenerative conditions has suggested that phytochemicals showing antioxidant activity may contribute to the prevention of these pathologies. The present review deals with phenolic compounds in plants and reports on recent studies. Moreover, the present work includes information on the relationships between the consumption of these compounds, via feeding, and risk of disease occurrence, i.e. the effect on human health. Results obtained on herbs, essential oils, from plants grown in tropical, subtropical and temperate regions, were also reported.