scholarly journals Determination of Total Phenolic and Flavonoid Content in Small Berries

2021 ◽  
Vol 83 (9) ◽  
pp. 579-583
Author(s):  
Renata Bellová ◽  
Dana Blahútová ◽  
Eva Culková ◽  
Peter Kubatka ◽  
Peter Tomčík

The authors of this article applied the determination of phenolic and flavonoid content in small berries to create a didactic cycle based on student-centered active learning (SCAL) in which students actively participated in the topic while studying and profile-forming as future biology and chemistry teachers. The fundamental part of the proposed didactic cycle is that students solve the following task: Determine the phenolic and flavonoid content in berries (Vaccinium myrtillus L., Vaccinium vitis-idaea L., and Vaccinium corymbosum L.) in your region. The submitted interdisciplinary topic is relevant to everyday life, and it aroused interest and enthusiasm among students. The students had the opportunity to test their theoretical knowledge in practical experimental research, and they attempted to work as researchers.

2021 ◽  
Vol 64 (1) ◽  
Author(s):  
Aslı Özkök ◽  
Merve Keskin ◽  
Aslı Elif Tanuğur Samancı ◽  
Elif Yorulmaz Önder ◽  
Çiğdem Takma

AbstractThis study aimed to determine the standard amount of antioxidant content and compounds of the propolis for the standardization of propolis. For this purpose, the total flavonoids, total phenolic, CUPRAC antioxidant capacity content and the diversity of phenolic and flavonoid components of these propolis samples were found by HPLC determined at the 23 propolis samples which were collected different regions of Turkey. Beside that, the similarities and differences of these 23 provinces to each other according to their antioxidant capacities were investigated by multidimensional scaling analysis. The total flavonoid content in the propolis samples were determined between 21.28 and 152.56 mg CE/g. The total phenolic content in the propolis samples was found between 34.53 mg and 259.4 mg GAE/g. CUPRAC antioxidant capacity of the propolis samples and antioxidant range was found from 95.35 to 710.43 mg TE/g. Also, 4 flavonoid [Quercetin (min.1.12–max.4.14 mg/g), Galangin (min.0.72–max.40.79 mg/g), Apigenin (min.1.07–max.17.35 mg/g), Pinocembrin (min.1.32–max.39.92 mg/g] and 6 phenolic acid [Caffeic acid (min.1.20–max.7.6 mg/g), p-Coumaric acid (min.1.26–max.4.47 mg/g), trans-Ferulic acid (min.1.28–max.4.92 mg/g), Protocatechuic acid (1.78 mg/g), trans-Cinnamic acid (min.1.05–max.3.83 mg/g), Caffeic Acid Phenethyl Ester (CAPE) (min.1.41–max.30.15 mg/g)] components were detected as mg/g, in different ratios in propolis samples collected from different regions. The feature of this study, so far, is to have the maximum number of samples representing the Turkish propolis, and so is thought to help to national and international propolis standard workings.


2018 ◽  
Vol 8 (3) ◽  
pp. 114-118
Author(s):  
Tabasum Ali ◽  
Amreen Naqash ◽  
Rukhsar Wadoo ◽  
Rumaisa Rashid ◽  
Ghulam Nabi Bader

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4399
Author(s):  
Norhasnida Zawawi ◽  
Pei Juin Chong ◽  
Nurul Nadhirah Mohd Tom ◽  
Nurkhairina Solehah Saiful Anuar ◽  
Salma Malihah Mohammad ◽  
...  

Honey is a well-known natural sweetener and is rich in natural antioxidants that prevent the occurrence of oxidative stress, which is responsible for many human diseases. Some of the biochemical compounds in honey that contribute to this property are vitamins and phenolic compounds such as phenolic acids and flavonoids. However, the extent to which these molecules contribute towards the antioxidant capacity in vitro is inconsistently reported, especially with the different analytical methods used, as well as other extrinsic factors that influence these molecules’ availability. Therefore, by reviewing recently published works correlating the vitamin, total phenolic, and flavonoid content in honey with its antioxidant activities in vitro, this paper will establish a relationship between these parameters. Based on the literature, vitamins do not contribute to honey’s antioxidant capacity; however, the content of phenolic acids and flavonoids has an impact on honey’s antioxidant activity.


Author(s):  
Sayed A. El-toumy ◽  
Joslin Y. Salib ◽  
Nabila H. Shafik ◽  
Asmaa S. Abd Elkarim ◽  
Gihan A. Mick

<p><strong>Objective: </strong>The current study was to deal the isolation and identification of secondary metabolites from <em>Polygonum equisetiforme</em> and evaluation of antioxidant activity of its extract.</p><p><strong>Methods: </strong>The methanol-water extract (7:3) of the air-dried aerial parts of <em>Polygonum equisetiforme</em> was fractionated and separated to obtain the isolated compounds by different chromatographic techniques. Structures of these compounds were elucidated by UV and 1D⁄2D H⁄ C NMR spectroscopy and compared with the literature data. The crude extract was evaluated for <em>in vitro</em> antioxidant activity using the 2,2 diphenyl dipicryl hydrazine (DPPH) method.</p><p><strong>Results: </strong>Ten secondary metabolites were isolated from <em>Polygonum equisetiforme</em> in this study. Of which three new flavonoids named as 3,5,7,2’,5’ pentahydroxyflavone 3-<em>O</em>-b-D-glucopyranoside (1), 3,5,7,2’,5’ pentahydroxyflavone 3-<em>O</em>-b-D-glucopyranoside 8 C-sulphated (2) and quercetin 3-<em>O-β</em>-D-glucucorinde 6''-methyl ester 8-sulphated (3) as well as quercetin 3-<em>O-β</em>-D-glucucorinde methyl ester (4), quercetin 3-<em>O-</em>β-D-glucopyranoside (5), quercetin 7-<em>O-β-</em>D-glucopyranoside (6),<em> </em>quercetin(7)<sub>, </sub>myricetin (8), <em>P</em><sub>-</sub>methoxy gallic acid methyl ester (9) and gallic acid (10). The antioxidant potential of <em>P. equisetiforme</em> extract was evaluated by investigating it's total phenolic and flavonoid content and DPPH radical scavenging activity whereby the extract showed significant antioxidant activity (IC<sub>50 </sub>= 37.45 μg/ml). The total phenolic and flavonoid content was found to be 130.79±5.502 and 45.8±1.63 μg/ml, respectively.</p><p><strong>Conclusion: </strong><em>Polygonum equisetiforme</em> is a promising medicinal plant, and our study tends to support the therapeutic value of this plant as an antioxidant drug.</p>


2018 ◽  
Vol 47 (4) ◽  
pp. 953-959
Author(s):  
Kishwar Jahan Shethi ◽  
Mohammad Zashim Uddin

To evaluate the antioxidant potential of less valued green leafy vegetables of Bangladesh, the methanolic extracts of Alternanthera sessilis, A. philoxeroides, A. paronychioides, Glinus oppositifolius and Portulaca oleracea were subjected to assay for total phenolic content, total flavonoid content and DPPH free radicle scavenging activity. Among the studied materials, A. sessilis showed the highest phenolic and flavonoid content. However, G. oppositifolius presented the lowest phenolic content (14.53 ± 0.48 mg of GAE/g of sample) and P. oleracea exhibited minimum (7.005 ± 0.25 mg of RUE/g of sample) flavonoid content. DPPH radical scavenging activity was found to increase with increase in the concentration of each individual material. A. philoxiroides (IC50 = 6.07 ± 0.27 μg/ml) was found as the most active in DPPH radical percentage inhibition, which was followed by A. sessilis (IC50 = 7.17 ± 0.67 μg/ml). Interestingly, A. paronychioides, in spite of having good amount of total phenolic and flavonoid content, showed less DPPH scavenging activity. No linear relationship was found to exist in case of the total phenolic, flavonoid content and DPPH scavenging activity among G. oppositifolius, P. oleracea and A. paronychioides. The results from different methods may differ substantially because each complex chemical reaction generates unique values. However, all the five plants exhibited creditable antioxidant activity and thus consumption of these vegetables may play important role in combating oxidative stresses and thereby help in retaining good health.


OALib ◽  
2017 ◽  
Vol 04 (11) ◽  
pp. 1-9
Author(s):  
Jinting Azieana ◽  
Mohd Noor Zainon ◽  
Abdullah Noriham ◽  
Mat Nor Rohana

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