Fluctuations in Phenolic Content and Antioxidant Capacity of Green Vegetable Juices during Refrigerated Storage

Characterization, Antioxidant Potential, and Pharmacokinetics Properties of Phenolic Compounds from Native Australian Herbs and Fruits

In recent decades, plant bioactive phenolic compounds gained much attention due to their various health benefits. Therefore, this study aimed to analyze native Australian river mint (Mentha australis), bush mint (Mentha satureioides), sea parsley (Apium prostratum), and bush tomatoes (Solanum centrale) for their bioactive metabolites, antioxidant potential, and pharmacokinetics properties. LC-ESI-QTOF-MS/MS was applied to elucidate these plants' composition, identification, and quantification of phenolic metabolites. This study tentatively identified 123 phenolic compounds (thirty-five phenolic acids, sixty-seven flavonoids, seven lignans, three stilbenes, and eleven other compounds). Bush mint was identified with the highest total phenolic content (TPC-57.70 ± 4.57 mg GAE/g), while sea parsley contained the lowest total phenolic content (13.44 ± 0.39 mg GAE/g). Moreover, bush mint was also identified with the highest antioxidant potential compared to other herbs. Thirty-seven phenolic metabolites were semi-quantified, including rosmarinic acid, chlorogenic acid, sagerinic acid, quinic acid, and caffeic acid, which were abundant in these selected plants. The most abundant compounds' pharmacokinetics properties were also predicted. This study will develop further research to identify these plants' nutraceutical and phytopharmaceutical potential.

Correlation between Solid Content and Antioxidant Activities in Umbelliferae Salad Plants

The aim of this study is to evaluate the antioxidant properties of 70% methanolic extracts and the correlation between several antioxidant activities in selected Umbelliferae plants, based on total phenolic content (TPC) and total flavonoid content (TFC). For Umbelliferae plants extracts, the IC₅₀ of DPPH radical (100 μM) quenching activities for extract, TPC, and TFC were 39∼179 μg dry weight (DW)/mL, 14.08∼38.11 μg TPC/mL, and 0.36∼1.51 μg TFC/mL, respectively. The oxygen radical absorbance capacity (ORAC) of extracts ranged from 11.44 to 42.88 mg Trolox equivalent (TE)/g DW extract, whereas ORAC for TPC and TFC was 47.40∼240.19 mg TE/g and 0.72∼11.22 g TE/g, respectively. The TPC had a superior linear correlation (r²=0.817) with 2,2’-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) values. Of the 14 Umbelliferae plant extracts, Sanicula rubiflora, Sanicula chinensis, Torilis japonica, Torilis scabra, and Angelica fallax showed the strongest antioxidant activity.