scholarly journals Extraction optimization of raspberry proanthocyanidins and determination of its antioxidant activities in vitro

2021 ◽  
pp. 693-712
Author(s):  
Hao Shi ◽  
Xiangyu Zhou ◽  
Xiaoe He ◽  
Renhui Ding ◽  
Rencai Wang ◽  
...  
2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Musbau Adewunmi Akanji ◽  
Samson Olasunkanmi Olukolu ◽  
Mutiu Idowu Kazeem

The leaves of Aerva lanata are one of the indigenous medicinal plants used in the management of diabetes mellitus and its associated complications in Africa. However, its effect on the activities of diabetes-related enzymes has not been investigated. This study evaluated the in vitro inhibitory effects of different extracts of the A. lanata leaf on the activities of diabetes-related enzymes (α-amylase and α-glucosidase) and chemically induced free radicals. Aqueous, ethanol, and hydroethanol extracts of A. lanata leaves were subjected to a standard enzyme inhibition assay followed by determination of modes of inhibition of the enzymes. The antioxidant activities of the extracts were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS). The results obtained showed that the hydroethanol extract of the A. lanata leaf optimally inhibited both α-amylase (IC50: 2.42 mg/mL) and α-glucosidase (IC50: 0.23 mg/mL). The Lineweaver-Burk plot revealed that the mode of inhibition of both enzymes by the hydroethanol extract was uncompetitive. However, the hydroethanol and aqueous extracts displayed the best DPPH and ABTS radical-scavenging ability, respectively. It can be concluded that the A. lanata extract inhibited the activities of both α-amylase and α-glucosidase uncompetitively, which may be attributed to its free radical-scavenging properties and rich phenolic composition.


Author(s):  
Manal Mortady Hamed ◽  
Aboelfetoh Mohamed Abdalla ◽  
Mosad Ahmed Ghareeb ◽  
Said Abdelhalim Saleh

Objective: The objective of this study was undertaken to estimate the total phenolic contents (TPCs), in vitro antioxidant of different solvent extracts of M. oleifera leaves, oral acute toxicity and LD50 determination of the 85% methanolic extract as well as the chromatographic isolation and identification of the extract constituents.Methods: The antioxidant activity of different solvent extracts of Moringa oleifera leaves were estimated using three antioxidant assays and the total phenolic contents (TPCs) were also evaluated using Folin-Ciocalteu’s assay. The n-BuOH extract undergoes further chromatographic isolation owing to the high antioxidant activity using 2, 2'-diphenyl-1-picrylhydrazyl radical (DPPH) method, which resulted in the isolation of seven compounds.Results: The results showed that the TPCs values of the tested extracts were varied from 309.52 to 43.28 mg gallic acid equivalent/g dry extract. The reducing power antioxidant activities (RPAA) were 0.434, 0.402, 0.395, 0.149, 0.143 and 0.124, while the total antioxidant capacity (TAC) values were 316.43, 203.35, 181.56, 86.70, 76.62 and 50.83 mg ascorbic acid equivalent/g dry extract; for n-BuOH, EtOAc, 85% MeOH, H2O, CH2Cl2, and pet. ether extracts, respectively. The oral acute toxicity study of the 85% methanol extracts of M. oleifera and M. peregrina revealed that; their LD50 values were 3458.3 and 4125 mg/kg respectively, thus the two plants could be classified as slightly toxic in the scale of Hodge and Sterner which reflected their nutrient values as edible plants. The isolated compounds were identified on the basis of their 1H and 13C-NMR spectra as; cis-p-coumaric acid 4-O-(2'-O-β-D-apiofuranosyl)-β-D-glucopyranoside (1), chlorogenic acid (2), niazirin (3), 3,4-dihydroxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(l→2)-α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-β-D-glucopyranoside (4), gallic acid (5), taxifolin (6), and benzyl-carbamo-thioethionate (7).Conclusion: The M. oleifera leaves showed promising antioxidant activities and slightly toxic behavior.


2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
A. A. Famuwagun ◽  
K. A. Taiwo ◽  
S. O. Gbadamosi ◽  
D. J. Oyedele ◽  
R. E. Aluko ◽  
...  

Optimization of the yield, total phenolic content (TPC), and total antioxidant activities (TAA) of polyphenol concentrates extracted from Solanum macrocarpon leaves was studied using response surface methodology. The process variables investigated included extraction temperature (30, 50, and 70°C), extraction time (2, 4, and 6 h), and dried leaf powder : water ratio (1 : 10, 1 : 20, and 1 : 30 w/v). Box–Behnken design resulted in 15 experimental runs. The results showed the following optimum extraction conditions: temperature, 49.05°C; extraction time, 243 min; leaf powder : water ratio, 1 : 22 w/v. The optimized extraction conditions gave polyphenol concentrate yield, TPC, and TAA values of 24.94%, 421.09 mg GAE/g, and 23.81 mg AAE/g, respectively. Results of the in vitro antioxidant activities of the polyphenol concentrate showed 2, 2-diphenyl-2-picrylhydrazyl hydrate, metal chelating ability, and ferric reducing ability values of 76.78%, 80.22%, and 56.46 mg AAE/g, respectively. The study concludes that the experimental values compared closely with the predicted values, which indicates suitability of the model employed for polyphenol extraction optimization from dried S. macrocarpon leaves.


Molecules ◽  
2020 ◽  
Vol 25 (20) ◽  
pp. 4685
Author(s):  
Mahwish Salman ◽  
Anam Tariq ◽  
Anam Ijaz ◽  
Shazia Naheed ◽  
Abeer Hashem ◽  
...  

Lactic acid bacteria (LAB) can synthesize antimicrobial compounds (AMCs) with nutritional and bioprotective properties in crops and food products. In the current study, AMCs of Lactobacillus coryniformis BCH-4 were evaluated to control fungal spoilage in maize grains. On maize grains treated with 75%–100% (v/v) concentrated AMCs, no fungal growth was observed even after 72 h of Aspergillus flavus inoculation. Proximate analysis of treatments A1 (raw grains), A2 (A. flavus inoculated grains) and A3 (A. flavus + AMCs inoculated grains) revealed that moisture was significantly (p ≤ 0.05) high in A2 than A3 and A1. Meanwhile, protein, fat, fiber and ash contents were significantly decreased in A2 compared to A1 and A3. Moreover, β-carotene contents were not statistically different between A1 and A3, while in A2 it was significantly decreased. HPLC analysis revealed the presence of 2-oxopropanoic acid, 2-hydroxypropane-1,2,3-tricarboxylic acid, 2-hydroxybutanedioic acid, 2-hydroxypropanoic acid, propanedioic acid and butanedioic acid, which also showed antifungal activity against Aspergillus flavus. FTIR spectroscopy revealed the presence of hydroxyl, carbonyl and ester-groups along with organic and fatty acids, thereby indicating their participation in inhibitory action. Furthermore, the AMCs were found to be a good alternative to chemical preservatives, thereby not only preserving the nutritive qualities but increasing the shelf life as well.


2021 ◽  
Vol 15 (6) ◽  
pp. 513-528
Author(s):  
Hatice Kızıltaş ◽  
Zeynebe Bingöl ◽  
Ahmet C. Gören ◽  
Saleh H. Alwasel ◽  
İlhami Gülçin

To evaluate the antioxidant activity of evaporated ethanolic extract of Ferula orientalis L. (EEFO) and lyophilized water extract of Ferula orientalis L. (WEFO) several in vitro antioxidant methods such as ABTS•+ scavenging activity, DPPH· scavenging activity, Fe3+reduction method, cupric ions (Cu2+) reduction capacity, and metal ion (Fe2+)-binding activities using ferrozine reagent were separately performed. Also, BHT, α-tocopherol and ascorbic acid were used as the standard antioxidant molecules. Moreover, some phenolic compounds that are responsible for antioxidant abilities of EEFO and WEFO were determined by LC-HRMS. EEFO and WEFO demonstrated effective antioxidant abilities when compared with the standards. EEFO demonstrated IC50 values of 1.946 µg/mL against acetylcholinesterase (AChE), 0.815 µg/mL against α-glycosidase, and 0.675 µg/mL against α-amylase.


2020 ◽  
Vol 4 (3) ◽  
pp. 200010
Author(s):  
Xiaojing Shena ◽  
Xiaojing Shena ◽  
Weiwei Jiang ◽  
Weiwei Jiang

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