scholarly journals Radical-Scavenging Activity and Ferric Reducing Ability ofJuniperus thurifera(L.),J. oxycedrus(L.),J. phoenicea(L.) andTetraclinis articulata(L.)

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Meryem El Jemli ◽  
Rabie Kamal ◽  
Ilias Marmouzi ◽  
Asmae Zerrouki ◽  
Yahia Cherrah ◽  
...  

Objective. The aim of this work is to study and compare the antioxidant properties and phenolic contents of aqueous leaf extracts ofJuniperus thurifera,Juniperus oxycedrus,Juniperus Phoenicea,andTetraclinis articulatafrom Morocco.Methods. Antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging ability, Trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP) assays. Also the total phenolic and flavonoids contents of the extracts were determined spectrophotometrically.Results. All the extracts showed interesting antioxidant activities compared to the standard antioxidants (butylated hydroxytoluene (BHT), quercetin, and Trolox). The aqueous extract ofJuniperus oxycedrusshowed the highest antioxidant activity as measured by DPPH, TEAC, and FRAP assays with IC50values of17.91±0.37 μg/mL,19.80±0.55 μg/mL, and24.23±0.07 μg/mL, respectively. The strong correlation observed between antioxidant capacities and their total phenolic contents indicated that phenolic compounds were a major contributor to antioxidant properties of these plants extracts.Conclusion. These results suggest that the aqueous extracts ofJuniperus thurifera,Juniperus oxycedrus,Juniperus phoenicea,andTetraclinis articulatacan constitute a promising new source of natural compounds with antioxidants ability.

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Shivraj Hariram Nile ◽  
S. H. Kim ◽  
Eun Young Ko ◽  
Se Won Park

The polyphenolic contents and the antioxidant activity of the skins and pulps of different grape cultivars were estimated using HPLC and DPPH antioxidant assay, respectively. The phenolics and flavonoids identified were quercetin, kaempferol, caffeic acid, p-coumaric acid, cinnamic acid, and (−)-epicatechin. The total phenolic contents were found to be the highest in the grape skin of Flouxa (>400 mg/100 g), followed by Campbell Early and Tamnara (>300 mg/100 g), and then by Red Globe and Ruby Seedless (>250 mg/100 g), and the total phenolic content was the lowest in Italia and Delaware (<60 mg/100 g). The antioxidant activities of the grape extracts varied from 12.5% (Ruby Seedless) to 60.2% (Hongiseul) for skins, whereas the antioxidant activities of the grape extracts varied from 35.4% (Campbell Early) to 84.5% (Hongiseul) for pulps. The grape pulps have stronger antioxidant activities than those of the grape skins. Our results suggest that the phenolic and flavonoid contents in extracts of grape skins and pulps showed statistically significant correlations with the free radical scavenging activity.


2016 ◽  
Vol 62 (1) ◽  
pp. 29-41 ◽  
Author(s):  
Marta Słowianek ◽  
Joanna Leszczyńska

SummaryIntroduction: Seasonings added to food enhance its flavor and texture. Some of them can also extend their shelf-lives thanks to the presence of antioxidant compounds. Objective: The aim of the study was to investigate twenty eight commercially available spices for the total phenolic contents and antioxidant activity. Methods: Total phenols were estimated according to the Folin-Ciocalteu method. Antioxidant activities of the extracts were determined with DPPH assay. Results: Our results showed that the most of analysed spices are rich in phenolic compounds and demonstrate good antioxidant activity. The total polyphenol content oscillated around 0.9-155.1 mg GAE/g with the lowest value for sesame and the highest for cinnamon. The DPPH radical scavenging ability expressed as % ranged from 4.1% for sesame to 94.9% for cloves. Moreover, a moderate correlation (r=0.63, p<0.05) was reported between antioxidant activity and total phenolics, revealing that phenolic compounds are the important antioxidant components in the examined spices. Conclusion: The study shows also that a lot of spices can serve as food preservatives and, at the same time, have a beneficial effect on human health.


Foods ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2058
Author(s):  
Franklin Brian Apea-Bah ◽  
Xiang Li ◽  
Trust Beta

White rice is an important staple food globally. It is a rich source of energy but is low in dietary phenolic antioxidants. This current research aimed at providing scientific evidence for an alternative rice dish that has increased phenolic-antioxidant health-promoting potential by combining white rice with red cowpea beans and cooking with dye sorghum leaves hydrothermal extract, as a source of natural colorant. Boiled white rice and the rice–cowpea–sorghum extract dish were freeze-dried, and the free and bound phenolic compounds of raw and cooked samples were extracted. Phenolic composition, total phenolic content (TPC), and antioxidant activities (measured by 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity, Trolox equivalent antioxidant capacity, and oxygen radical absorbance capacity methods) of the raw and cooked samples were determined. Combining white rice with cowpea seeds and sorghum leaves extract significantly (p < 0.0001) increased the TPC and antioxidant activities of the rice due to the higher TPC and antioxidant activities of cowpea and sorghum leaves. Although boiling caused substantial losses of flavonoids and anthocyanins in the rice–cowpea–sorghum extract composite meal, the resulting dish had higher TPC and antioxidant activities than boiled white rice. Compositing white rice with phenolic-rich pulses can be an innovative approach to providing alternative healthy rice dishes to consumers.


Author(s):  
Jagriti Chandrakar ◽  
Satish Dubey ◽  
Kundan Ojha ◽  
Rashmi Dehariya ◽  
Ashwini Kumar Dixit

Cordia macleodii, an important medicinal plant traditionally used for the treatment of various disorders, including wound healing, jaundice, gastric ulcer, hepatoprotective activity and antivenom potential, thus the plant showed the high antioxidant properties. Successive extraction of leaf and barks powder with methanol and water was tested for quantitative determination of total phenolics, total flavonoids and various in vitro antioxidant activities. Phytochemical screening of crude plant extracts revealed the presence of sterols, alkaloid, flavonoid, phenolic, Reducing sugar, glycosides, tannins and saponins. All extracts showed the significant total phenolic and flavonoid contents and as well as radical scavenging and iron-chelating activities. Among all, methanol leaf extract was observed to be higher antioxidant activity than that of other extract. The methanol extracts showed greater antioxidant activity by DPPH scavenging the free radical with IC50 values of 7.63 ± 0.38 μg gm-1 along with scavenged free radical in a concentration depended manner, which is compare to the standard ascorbic acid.  Our results revealed that the presence of grater antioxidant activity of C. macleodii extract may be due to the high level of flavonoid and phenolic content in the plant. These results clearly indicated that C. macleodii is an effective natural antioxidant. Key words: Cordia macleodii, antioxidant, radical scavenging, phenolics, flavonoid, phytochemical.


Antioxidants ◽  
2019 ◽  
Vol 8 (7) ◽  
pp. 215 ◽  
Author(s):  
Cai-Ning Zhao ◽  
Guo-Yi Tang ◽  
Shi-Yu Cao ◽  
Xiao-Yu Xu ◽  
Ren-You Gan ◽  
...  

Tea is among the most consumed drink worldwide, and its strong antioxidant activity is considered as the main contributor to several health benefits, such as cardiovascular protection and anticancer effect. In this study, the antioxidant activities of 30 tea infusions, which were obtained by the mimic of drinking tea of the public, from green, black, oolong, white, yellow and dark teas, were evaluated using ferric-reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) assays, ranging from 504.80 ± 17.44 to 4647.47 ± 57.87 µmol Fe2+/g dry weight (DW) and 166.29 ± 24.48 to 2532.41 ± 50.18 µmol Trolox/g DW, respectively. Moreover, their total phenolic contents (TPC) were detected by Folin-Ciocalteu assay and were in the range of 24.77 ± 2.02 to 252.65 ± 4.74 mg gallic acid equivalent (GAE)/g DW. Generally, Dianqing Tea, Lushan Yunwu Tea, and Xihu Longjing Tea showed the strongest antioxidant activities among 30 teas. Furthermore, the phenolic compounds in tea infusions were identified and quantified, with catechins most commonly detected, especially in green tea infusions, which were main contributors to their antioxidant activities. Besides tea polyphenols, considerable content of caffeine also presented in 30 tea infusions.


2009 ◽  
Vol 6 (2) ◽  
pp. 227-231 ◽  
Author(s):  
S. A. Adesegun ◽  
A. Fajana ◽  
C. I. Orabueze ◽  
H. A. B. Coker

The antioxidant activities of crude extract ofPhaulopsis fascisepalaleaf were evaluated and compared with α-tocopherol and BHT as synthetic antioxidants and ascorbic acid as natural-based antioxidant.In vitro, we studied its antioxidative activities, radical-scavenging effects, Fe2+-chelating ability and reducing power. The total phenolic content was determined and expressed in gallic acid equivalent. The extract showed variable activities in all of thesein vitrotests. The antioxidant effect ofP. fascisepalawas strongly dose dependent, increased with increasing leaf extract dose and then leveled off with further increase in extract dose. Compared to other antioxidants used in the study, α-Tocopherol, ascorbic acid and BHT,P. fascisepalaleaf extract showed less scavenging effect on α,α,-diphenyl-β-picrylhydrazyl (DPPH) radical and less reducing power on Fe3+/ferricyanide complex but better Fe2+-chelating ability. These results revealed thein vitroantioxidant activity ofP.fascisepala.Further investigations are necessary to verify these activitiesin vivo.


2021 ◽  
Author(s):  
Ahmed Al-Mustafa ◽  
Mohammad Al-Tawarah ◽  
Mohammed Sharif Al-Sheraideh ◽  
Fatima Attia Al-Zahrany

Abstract Background: We investigated Juniperus Phoenicea (J. Phoenicea) and Calicotome Villosa (C. Villosa) from Jordan for phenolic contents, antioxidant, anti β-Galactosidase activities, in an attempt to rationalize its use in lactose metabolism disorders. The kinetic parameters of leave extracts, galactose, glucose, fructose and acarbose were evaluated. Also, the thermodynamic parameters of the enzyme thermal inactivation were determined. Methods: JP and cv crude methanolic extracts were evaluated for 1,1-diphenyl,2-picrylhydrazyl (DPPH) free radical scavenging activity and ferric reducing antioxidant power (FRAP). Further, β-Galactosidase inhibitory activities were performed using O-nitrophenyl-beta-D-galactopyranoside as substrate. Moreover, total phenolic contents, flavonoids and flavonols of plants extracts were determined and expressed in mg of gallic acid equivalent (mg GAE/g dry extract) or rutin equivalent per gram of dry extract (mg RE/g dry extract).Results: Phytochemical screening of the crude extract of J. Phoenicea and C. Villosa leaves contained phenols, alkaloids, flavonoids, terpenoids, anthraquinones and glycosides. J. Phoenicea exhibited high flavonoids and flavonols contents than C. Villosa but both J. Phoenicea and C. Villosa contained high phenolic and showed concentration dependent DPPH scavenging activity, with J. Phoenicea (IC50 =11.1 μg/ml), C. Villosa (IC50 =15.6 μg/ml), respectively. According to FRAP assay, the antioxidant power activity of plants extracts was concentrations dependent. The β-galactosidase % inhibition was increased as the concentration of of J. phoenicea, C. villosa and rutin increased. The mode of inhibition of β-galactosidase by J. phoenicea (IC50= 65 µg/ml) and C. villosa (IC50= 700 µg/ml) extracts was non-competitive and mixed-inhibition, respectively. Also, rutin was affected in a competitive (IC50 = 75 µg/ml) inhibition. β-galactosidase half-life was 108 min at 55°C, thermodynamic parameters revealed an activation energy of 208.88 kJ mol-1 and the inactivation kinetic follows a first-order reaction with k-values ranges between 0.0862 and 0.0023 min-1. The enzyme showing a decreasing trend of enthalpy of denaturation (∆H°) as temperature increase but value of free energy of thermal denaturation (∆G°) for β-galactosidase was decreased with increasing in temperature. The calculated entropy of inactivation (∆S°) at each temperature showed positive values, which means there are no significant processes of aggregation.Conclusions: J.phoenicea and C.villosa have inhibiting effect on β-galactosidase activity. Thermodynamic approach shows an enzyme stable and suggests that inactivation mechanism is based on molecular structural changes.


2020 ◽  
Vol 122 (10) ◽  
pp. 3029-3038
Author(s):  
Seok Shin Tan ◽  
Seok Tyug Tan ◽  
Chin Xuan Tan

PurposeSalak (Salacca zalacca) is an underutilised fruit. The bioactivities of this fruit have rarely been studied scientifically. Thus, the present study aimed to determine the antioxidant activity of extracts derived from the peel, fruit and kernel of the Salak fruit, as well as the hypoglycemic and anti-hypertensive properties of Salak peel extracts.Design/methodology/approachThe peel, fruit and kernel of the Salak were extracted using distilled water, methanol and ethanol. Antioxidant activities, angiotensin-converting enzyme (ACE) and alpha-amylase inhibition properties of the extracts were estimated via in vitro standard methods. Besides, the total phenolic content (TPC) and total flavonoid content (TFC) of the extracts were also determined in the present study. The antioxidant activities of different parts of Salak extracts were determined by ferric-reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) methods. Percent of radical scavenging properties were calculated via DPPH assay. The hypoglycemic and anti-hypertensive properties of Salak peel were evaluated using alpha-amylase inhibition and ACE assays, respectively.FindingsFruit extracts of Salak in methanol were found to exhibit the highest TPC (10.27 ± 0.12 mg GAE/g), TFC (11.04 ± 0.89 mg CE/g) and antioxidant properties amongst all samples whereby the TPC and TFC were strongly correlated with antioxidant activities. On the other hand, distilled water extracted Salak kernel showed to have the lowest TPC (0.53 ± 0.05 mg GAE/g), TFC (0.37 ± 0.01 mg CE/g) and antioxidant properties amongst all the Salak extracts. Peel extracts exhibit comparable antioxidant activities with fruit extracts in the current findings. In addition, peel extracts indicated some extend of ACE and alpha-amylase inhibition activities regardless of the solvents used. Methanol and ethanol peel extracts indicated no significant difference (p < 0.05) ACE (98%) and alpha-amylase (90%) inhibition activities. However, distilled water extracted Salak peel showed significantly lower ACE and alpha-amylase inhibition in comparison to methanol and ethanol peel extracts.Originality/valueThe present findings suggested that the fruit of Salak exhibits the highest antioxidant properties, followed by the peel and lastly, the kernel, which shows the lowest antioxidant properties amongst all the samples. The results also indicated that the peel extracts have ACE and alpha-amylase inhibition activities.


2013 ◽  
Vol 11 (2) ◽  
pp. 191-197 ◽  
Author(s):  
Ishrat Nimmi ◽  
Ismet Ara Jahan ◽  
M Hemayet Hossain ◽  
Mohammad Burhan Uddin ◽  
M Sohel Rana ◽  
...  

A comparative study of antioxidant properties on two varieties of Phyllanthus (Phyllanthus niruiri L. & Phyllanthus urinaria L. leaves) growing in Bangladesh was done in the present study. Five complimentary test methods namely DPPH free radical scavenging activity, reducing power assay, total antioxidant capacity, total phenolic and flavonoid contents determination were used for the evaluation of antioxidant properties of two species of Phyllanthus. In the present investigation for the evaluation of antioxidant activities the concentration is expressed by the ratio of crude sample per solvent volume instead of extract weight per solvent volume. Based on these concentrations the investigated P. niruri L. and P. urinaria L. leaves extracts exhibited significant results. At 2 mg/ml concentration DPPH radical scavenging capacity of the methanol extract of both the plants was found to show significant (>90%) activity which is comparable to Ascorbic acid and BHA. In case of reducing power tests for both the extract, the activity of P. urinaria is comparable to that of BHA and AA and that of P. niruiri is comparable to BHA. P. niruiri showed better antioxidant potential than that of P. urinaria based on the observed results of their corresponding methanol extract. DOI: http://dx.doi.org/10.3329/dujps.v11i2.14579 Dhaka Univ. J. Pharm. Sci. 11(2): 191-197, 2012 (December)


2013 ◽  
Vol 8 (8) ◽  
pp. 1934578X1300800 ◽  
Author(s):  
Chahrazed Hamia ◽  
Nadhir Gourine ◽  
Hadjer Boussoussa ◽  
Mokhtar Saidi ◽  
Emile M. Gaydou ◽  
...  

The essential oil obtained by hydrodistillation of the flowers of Rhanterium adpressum Coss. & Durieu was analyzed using GC and GC-MS. The essential oil was very rich in monoterpene compounds. The major components identified were the monoterpene hydrocarbons: camphene (21.8%), myrcene (19.3%) and α-pinene (17.4%). Other compounds, including limonene, β-pinene and terpinol-4-ol, were present in low content (4–6%). The composition of the fatty acids in the lipid extract obtained from the flowers was also investigated by GC and GC-MS. The main fatty acids identified were palmitic (47.4%), oleic (12.9%) and stearic acids (10.6%). The total phenolic contents and the antioxidant activities were also evaluated for both extracts. The total phenolic contents were determined using the Folin-Ciocalteu reagent and the antioxidant activities were measured using three different assays: DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging activity, FRAP (ferric reducing antioxidant potential) and a molybdenum assay. As a result of these tests, the lipid extract exhibited the highest antioxidant activities in comparison with the essential oil extract.


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