Evaluation Of Free Radical Scavenging Activity Research Articles

Impact of storage conditions on the bioactive compounds and antioxidant capacity of commercial orange jam

Storage conditions are important factors for fruit jam quality and antioxidant potential. The effects of storage time and temperature on stability of bioactive compounds such as total phenolics and flavonoids and total antioxidant capacity of orange jam were investigated. The jam samples were stored for a period of 30 days at 25 and 35°C. Total phenolic content of samples was determined by the Folin-Ciocalteu method. Antioxidant capacity was determined by spectrophotometric methods and was based on the evaluation of free-radical scavenging activity (FRSA) using DPPH radical and ferric reducing power (FRP). In the current study, the results showed that by the end of storage, the bioactive compound contents and antiradical activity decreased significantly. Also, extremely significant correlation (p < 0.001) was observed between phenolic and flavonoid contents, and antioxidant capacity (FRSA and FRP) of orange jam. Regardless of the phenolic compound loss after storage, orange jams are good sources of substances with antioxidant potential.

In vitro Evaluation of Wild Fruits and Leaves for Potential Carbohydrate Hydrolyzing Enzyme Inhibition

Four wild foods dandelion leaf ‐ (Taraxacam officinale), grape (Vitis riparia) plantain (Plantago major), and beach plum (Prunus maritima) ‐, were extracted in water followed by C18 column extraction. The phenolic content was evaluated using the Folin‐Ciocalteau's Assay and determined to be 39.5 μg/mg GAEq, 116.2 μg/mg GAEq, 14.3 μg/mg GAEq, and 351.1 μg/mg GAEq for the dandelion, grape, plantain, and plum respectively. The antioxidant activity was evaluated in terms of free‐radical scavenging activity, by using the DPPH assay. Single dose evaluation showed that the sample with the highest free‐radical scavenging activity was the beach plum with 70.2% antioxidant activity, followed by grape with (58.6%), dandelion (50.0%), and plantain (44.9%). Dose‐dependent evaluation of free‐radical scavenging activity is currently underway. Previous reports have shown that phenolic phytochemicals are excellent inhibitors of carbohydrate hydrolyzing enzymes. To determine the possible effect of our samples for type 2 diabetes prevention, we will evaluate their dose‐dependent inhibitory effect against two major carbohydrate hydrolyzing enzymes (alpha‐glucosidase and alpha‐amylase). Completion of this research will provide the basic biochemical rationale for the deeper evaluation of samples with high inhibitory activity.

Evaluation of Free Radical-Scavenging Activity of Sea Urchin Pigments Using HPTLC with Post-Chromatographic Derivatization

Chromatographic separation, analysis of in situ radical-scavenging activity, and quantitative analysis of green sea urchin shell pigments were carried out by online HPTLC-DAD and HPTLC-DPPH methods. Methanol:chloroform:acetic acid:water (11:50:5:2, v/v) was selected as the best mobile phase on silica gel plates for the separation of the pigments. Two pigment spots, S1 and S2, were observed on the TLC plates, while echinochrome A was not detected in the pigment extract of green sea urchin shells. Based on the estimated ID50 values, the antiradical activity was S2 (0.043 μg) > S1 (0.058 μg) > echinochrome A (0.134 μg).

Chemical fingerprinting and evaluation of free-radical scavenging activity of multivitamin supplements

Chemical fingerprinting and evaluation of free-radical scavenging activity of multivitamin supplements