scholarly journals Effect of drying techniques on the retention of antioxidant activities of Saskatoon berries

Author(s):  
Pranabendu Mitra ◽  
Venkatesh Meda ◽  
Rick Green

The main objective of this research was to compare the retention of antioxidant activity and total anthocyanin content of Saskatoon berries dried by freeze drying, microwave-vacuum drying, thin layer hot air drying and vacuum drying. Antioxidant activity of berry samples was determined by DPPH radical scavenging and ABTS radical scavenging, and the pH differential method was used to determine total anthocyanin content of the berry samples. The results showed that the freeze dried Saskatoon berries exhibited the highest retention of anthocyanin and antioxidant activity among the dried samples, followed by microwave-vacuum dried berries, thin layer hot air dried berries and vacuum dried berries. There were significant differences between the berry samples at P<0.05.  DPPH radical scavenging and ABTS radical scavenging were correlated linearly with an R2 value of 0.99 at P<0.05 showing their effectiveness for the determination of the antioxidant activity of the Saskatoon berries. However, the DPPH radical scavenging assay was more effective than the ABTS radical scavenging assay. The results also showed that antioxidant activity of the berries was highly correlated with the total anthocyanin content of the fruit. The reduction of anthocyanin in dried berry samples was linearly correlated with the reduction of DPPH radical scavenging with an R2 value of 0.97 at P<0.05 and, also, linearly correlated with the reduction of ABTS radical scavenging with an R2 value of 0.88 at P<0.05.

2013 ◽  
Vol 2 (2) ◽  
Author(s):  
Pranabendu Mitra ◽  
Venkatesh Meda ◽  
Rick Green

The main objective of this research was to compare the retention of antioxidant activity and total anthocyanin content of Saskatoon berries dried by freeze drying, microwave-vacuum drying, thin layer hot air drying and vacuum drying. Antioxidant activity of berry samples was determined by DPPH radical scavenging and ABTS radical scavenging, and the pH differential method was used to determine total anthocyanin content of the berry samples. The results showed that the freeze dried Saskatoon berries exhibited the highest retention of anthocyanin and antioxidant activity among the dried samples, followed by microwave-vacuum dried berries, thin layer hot air dried berries and vacuum dried berries. There were significant differences between the berry samples at P<0.05.  DPPH radical scavenging and ABTS radical scavenging were correlated linearly with an R2 value of 0.99 at P<0.05 showing their effectiveness for the determination of the antioxidant activity of the Saskatoon berries. However, the DPPH radical scavenging assay was more effective than the ABTS radical scavenging assay. The results also showed that antioxidant activity of the berries was highly correlated with the total anthocyanin content of the fruit. The reduction of anthocyanin in dried berry samples was linearly correlated with the reduction of DPPH radical scavenging with an R2 value of 0.97 at P<0.05 and, also, linearly correlated with the reduction of ABTS radical scavenging with an R2 value of 0.88 at P<0.05.


2018 ◽  
Vol 71 (6) ◽  
pp. 399 ◽  
Author(s):  
Jothinathan Sathiya Savithri ◽  
Perumal Rajakumar

Novel triazole bridged dendrimers with rhodamine B derivative as surface groups have been achieved using click chemistry by both divergent and convergent approaches. Rhodamine B decorated dendrimers 1, 2, and 3 were synthesised up to the second generation with spirolactam grafted at the terminal. The UV and fluorescence intensity increases with the increase in the dendritic generation. The synthesised rhodamine B decorated dendrimers show significant antioxidant behaviour compared with the standards butylated hydroxy toluene (BHT) and gallic acid when tested by 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging assay and hydroxyl radical scavenging assay methods, respectively. Rhodamine B decorated higher generation dendrimers exhibit better antioxidant activity than the lower generation dendrimers due to the presence of a greater number of triazole branching units and rhodamine B derivative surface units.


Author(s):  
GAURAV SHARMA ◽  
ANKITA THAKUR ◽  
SOHAN LAL ◽  
ROHIT KUMAR NADDA

Objective: The objective of the present study was the analysis of phytochemicals in various extracts of Azadirachta indica leaves, comparative evaluation of antibacterial activity of the various extracts of A. indica leaves against Escherichia coli and Staphylococcus aureus, and comparative evaluation of antioxidant activity in various extracts of A. indica leaves using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. Methods: Various extracts were prepared by crushing the samples. Antibacterial susceptibility test, various phytochemical tests for qualitative analysis, and DPPH radical scavenging assay for antioxidant activity were performed. Results: The result suggested that alkaloids, flavonoids, and terpenoids were present in all the four extracts. Tannins were absent in the ethyl acetate extract, and phenols were only present in the ethyl acetate extract. Sterols and phlobatannins were absent in all the four extracts. Saponins were only present in the aqueous extract, and amino acids were only present in the ethyl acetate extract. The bacterial strains S. aureus and E. coli were used against the different extracts of A. indica leaves, i.e., methanol, chloroform, ethyl acetate, and aqueous. Conclusion: The results suggested that bioactive compounds found in leaves of A. indica contribute to its pharmacological activities.


2018 ◽  
Vol 38 (1) ◽  
pp. 1
Author(s):  
Nanik Suhartatik ◽  
Akhmad Mustofa

Anthocyanin is a bioactive component which give basic color of red, purple, and blue to blackish foodstuffs. So, the anthocyanin could be developed as a natural pigment in foodstuffs, but it is unstable. Several studies have been conducted to improve its stability in the food system. The purpose of this study was to analyze the stability of anthocyanin in isotonic beverages as food system with the addition of copigmentation compound derived from star fruit flower extract. The stability of the isotonic beverage was tested at some heating temperatures and storage periods. Isotonic drink were formulated using anthocyanin extracted from glutinous rice flour. Isotonic beverages consist of sucrose, fructose, sodium benzoate, citric acid, KCl, and K2PO4 which were regulated containing anthocyanin equivalent to 25 mg/L. Added ingredients to increase the stability of anthocyanin in isotonic drinks was 5% star-fruit flower extract. During storage, the phenolic content, anthocyanin, and antioxidant activity of isotonic beverages were observed. The results showed that heating process declined the anthocyanin content significantly, from 25 mg/L to 2.82 mg/L. Decreased level of anthocyanin also occurred during storage. Heating at 50, 65, and 70 °C gave no significant difference of phenol content. Similar to its ability to capture DPPH radicals (% RSA DPPH, radical scavenging activity 2.2-diphenyl-1-picrylhydrazyl). Increasing the temperature from 50 to 70 °C would increase the stability of anthocyanin, total phenolic, and also the antioxidant activity. Meanwhile, storage would decrease the anthocyanin content but increase the phenolic content and the antioxidant activity. ABSTRAKAntosianin merupakan komponen bioaktif dan warna dasar bahan makanan yang berwarna merah, ungu, biru hingga kehitaman. Antosianin berpotensi dikembangkan sebagai pewarna alami untuk makanan, akan tetapi pigmen ini bersifat tidak stabil. Beberapa penelitian telah dilakukan untuk meningkatkan stabilitasnya dalam sistem pangan. Tujuan dari penelitian ini adalah untuk menganalisis stabilitas antosianin dalam minuman isotonik sebagai sistem pangan dengan penambahan senyawa kopigmentasi yang berasal dari ekstrak bunga belimbing. Stabilitas minuman isotonik diuji pada beberapa suhu pemanasan dan periode penyimpanan. Minuman isotonik diformulasikan menggunakan antosianin hasil ekstraksi dari tepung beras ketan hitam. Minuman isotonik terdiri dari sukrosa, fruktosa, Na-benzoat, asam sitrat, KCl, dan K2PO4 yang diatur mengandung antosianin setara dengan 25 mg/L. Bahan yang ditambahkan untuk meningkatkan stabilitas antosianin pada minuman isotonik adalah ekstrak bunga maya (belimbing) 5%. Selama penyimpanan diamati kadar fenolik, kadar antosianin, dan aktivitas antioksidan dari minuman isotonik. Hasil penelitian menunjukkan bahwa proses pemanasan menyebabkan penurunan yang signifikan dari kadar antosianin, dari semula 25 mg/L menjadi hanya 2,82 mg/L saja. Penurunan kadar antosianin terjadi juga selama penyimpanan. Perlakuan suhu 50, 65, dan 70 °C memberikan perbedaan kadar fenolik yang tidak signifikan. Begitu pula dengan kemampuannya untuk menangkap radikal DPPH (% RSA DPPH, radical scavenging activity 2,2-diphenyl-1-picrylhydrazyl). Kenaikan suhu dari 50 menjadi 70 °C, meningkatkan stabilitas antosianin, meningkatkan kadar fenolik, dan aktivitas antioksidannya. Sementara proses penyimpanan membuat kadar antosianin semakin menurun dan meningkatkan kadar fenolik serta aktivitas antioksidannya.


2020 ◽  
Vol 13 (4) ◽  
pp. 2093-2099
Author(s):  
Nazim Hussain ◽  
Bibhuti Bhushan Kakoti ◽  
Mithun Rudrapal ◽  
Zubaidur Rahman ◽  
Mokinur Rahman ◽  
...  

Cordia dichotoma Forst.has been used in the management of pain and inflammations in traditional medicine. However, the anti-inflammatory activity of the methanolic extract of C. dichotoma(MECD) bark has not been reported so far. This work was, therefore, aimed at investigating the anti-inflammatory activity of C. dichotomabark extract. The antioxidant activity was evaluated to justify the anti-inflammatory action of MECD on the basis of its radical scavenging property. The extract of C. dichotomawas obtained by Soxhlation of bark powder using methanol as solvent. The anti-inflammatory activity was determined by the carrageenan induced paw edemamodel in ratsat two different dose levels, viz., 250 and 500 mg/kg. The antioxidant activity was evaluated using DPPH radical scavenging assay. The antioxidant activity was performed in vitro by DPPH radical scavenging assay using ascorbic acid as the standard drug. In anti-inflammatory activity, maximum inhibition of edema was observed after 4 hours of experimental period. At lower test dose (250 mg/kg b.w.), the percentage inhibition of paw edema was 29.7 %, while 48.6 % inhibition of edema was observed at higher dose (500 mg/kgb.w.). The percentage inhibition of paw edema was significant relative to the control group. The standard indomethacin group also exhibited sufficiently high level of anti-inflammatory effect with 56% inhibition of paw edema at 5 mg/kg dose. In in vitroantioxidant activity, the MECD exhibited good DPPHradical scavenging activity with the IC50 vale of 62.46 µg/ml, whereas the standard drug, ascorbic acid showed comparatively more antioxidant activity with IC50 of 27.66 µg/ml.However, our study scientifically validates the folkloric claim as well as traditional uses of C. dichotomaas anti-inflammatory medication. It is suggested that the anti-inflammatory activity of C. dichotomamay be due to the antioxidant potential of phenolic phytoconstituents or plant flavonoids present in the methanolic bark extract.


2011 ◽  
Vol 6 (11) ◽  
pp. 1934578X1100601
Author(s):  
Mudasir A. Tantry ◽  
Aziz A. Rahman

Bioassay guided fractionation of an ethanolic extract of Polygonum amplexicaule D. Don led to the isolation of amplexicine, a new flavan-3-ol (1), along with khellactone (2). The structure of the isolates was established by UV, IR, HRESI/MS and NMR, including 1D and 2D experiments. Compound 1 exhibited considerable antioxidant activity in a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay.


2015 ◽  
Vol 10 (11) ◽  
pp. 1934578X1501001
Author(s):  
Diane Patricia Apie Gossan ◽  
Abdulmagid Alabdul Magid ◽  
Philomène Akoua Yao-Kouassi ◽  
Damien Le Faucheur ◽  
Antoine Ahibo Coffy ◽  
...  

A new flavonol diglycoside, rhamnocitrin-3- O-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside, was isolated from the leaves of Ventilago Africana. in addition to 11 known flavonoids. Their structures were determined by spectroscopic methods including 1D- and 2D-NMR, and HR-ESI-MS analysis. The isolated compounds were evaluated for their antioxidant activity by using DPPH radical-scavenging assay. Compounds 4, 7–9 have discrete to good antioxidant potential with EC50 values ranging from 20.9 to 40.4 μM. compared with ascorbic acid (EC50 60 μM) used as positive control.


2014 ◽  
Vol 92 (12) ◽  
pp. 1163-1168 ◽  
Author(s):  
Razieh Azimi ◽  
Robabeh Baharfar

A series of spiro-pyranoxindole derivatives were prepared in good yields via a three-component reaction of isatins with activated methylene reagents and kojic acid using 1,4-diazabicyclo[2.2.2]octane (DABCO) immobilized on mesoporous SBA-15 as a heterogenized organocatalyst in aqueous media. The synthesized compounds were evaluated for their antioxidant activity by a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay.


F1000Research ◽  
2018 ◽  
Vol 7 ◽  
pp. 1839
Author(s):  
Harlinda Kuspradini ◽  
Indah Wulandari ◽  
Agmi Sinta Putri ◽  
Sabeti Yulis Tiya ◽  
Irawan Wijaya Kusuma

Background: Litsea angulata is a plant species belonging to Lauraceae family that is distributed throughout Indonesia, Malaysia, and New Guinea. The seeds have been traditionally used by local people in Kalimantan, Indonesia for the treatment of boils; however, there is no information about the potency of its branch, bark and leaves yet. This study aimed to determine the antioxidant, antimicrobial activity as well as the phytochemical constituent of Litsea angulata branch, bark, and leaves. Methods: Extraction was performed by successive maceration method using n-hexane, ethyl acetate, and ethanol solvent. Antioxidant activity was evaluated by DPPH radical scavenging assay. The antimicrobial activity using the 96 well-plate microdilution broth method against Staphylococcus aureus and Streptococcus mutans. Results: Based on the phytochemical analysis, it showed that extract of L. angulata contains alkaloids, flavonoids, tannins, terpenoids, and coumarin. The results showed that all extracts of plant samples displayed the ability to inhibit DPPH free radical formation and all tested microorganisms. Conclusions: L. angulata contains secondary metabolites such as alkaloids, flavonoids, tannins, terpenoids, carotenoids, and coumarin. The antioxidant activity on different plant extracts was a range as very strong to weak capacity. All extracts in this study could inhibit the growth of S. aureus and S. mutans.


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