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Rosehip fruits, characterized by their high concentrations of bioactive compounds and antioxidant activity (AA), have been traditionally used to make jams, infusions, and juices. Thus, the objective of this research was to evaluate the stability of rosehip juice by determining the concentrations of bioactive compounds and total phenols and the AA using chromatographic and spectroscopic methods. The stability of the juice was evaluated with three treatments and different storage conditions, namely, unpasteurized–refrigerated, pasteurized–room temperature, and pasteurized–refrigerated, and measurements were taken for eight months. Individual and total phenolic compounds, evaluated by chromatographic methods, reported differences until the end of this study. The total phenolic compounds by Folin–Ciocalteu method presented an average decrease of 57% in the three treatments in relation to the initial conditions. On the other hand, the ascorbic acid content decreased considerably, disappearing at week six. Furthermore, for the unpasteurized–refrigerated and pasteurized–refrigerated samples, a correlation was found between flavonols, total phenols, ascorbic acid, and antioxidant activity determined by the TEAC method. For the pasteurized–room temperature samples, correlations were found between the levels of several flavonols, hydroxycinnamic acid, total phenols, and ascorbic acid and the antioxidant activity determined by the CUPRAC method. The stability of the compounds was mainly correlated with the storage conditions of the juice and not with pasteurization. The highest stability was observed for the unpasteurized–refrigerated and pasteurized–refrigerated samples. Although the concentrations of the compounds evaluated decreased during this study, significant levels of AA persisted, providing beneficial characteristics for consumer health. [ABSTRACT FROM AUTHOR]

Malabar spinach (Basella alba), amaranth (Amaranthus tricolor), and sweet potato (Ipomoea batatas) are leafy vegetables found in Southwest China. The variation of chlorophyll, carotenoids, ascorbic acid, total flavonoids, phenolic compounds, and antioxidant capacity was studied in the leaves and stems of the three vegetables. The content of main health-promoting compounds and the antioxidant capacity in the leaves were higher than that in the stems, indicating that the leaves of the three vegetables possess greater nutritional value. The trend of total flavonoids in all three vegetables was similar to the trend of antioxidant capacity, suggesting that the total flavonoids may be the major antioxidants wihin these vegetables. Eight individual phenolic compounds were detected in three different vegetables. The most abundant levels of individual phenolic compounds in the leaves and stems of malabar spinach, amaranth, and sweet potato were 6′-O-feruloyl-d-sucrose (9.04 and 2.03 mg g−1 DW), hydroxyferulic acid (10.14 and 0.73 mg g−1 DW), and isorhamnetin-7-O-glucoside (34.93 and 6.76 mg g−1 DW), respectively. Sweet potato exhibited a higher total and individual phenolic compound content compared to malabar spinach and amaranth. Overall, the results demonstrate that the three leafy vegetables possess high nutritional value, and could be used not only for consumption but also in various other fields, including medicine and chemistry. [ABSTRACT FROM AUTHOR]

The mushroom is an important food for the rural tribal populations in Manipur, because of its high nutritional contents. In this study, we report on the nutritional profile of three wild edible mushrooms consumed by the tribal populations of Manipur viz.: Macrocybe gigantea J124; Lactifluus leptomerus J201 and Ramaria thindii J470. The studied mushrooms possess a high protein content of 37.6%, 20.8% and 16.4%, respectively. They have a high vitamin C content with low vitamin B1, B2 and folic acid. Among the three mushrooms, M. gigantea J124 possesses the highest mineral content, followed by R. thindii J470 and L. leptomerus J201. The total phenolic content of L. leptomerus J201, M. gigantea J124 and R. thindii J470 were 26.206, 29.23 and 30.99 mg GAE/g, with flavonoid content of 6.646, 6.854 and 9.187 mg quercetin/g, respectively. R. thindii J470 has the highest TPC and TFC content, which correlates with its DPPH radical scavenging activity. The IC50 values for R. thindii J470, M. gigantea J124 and L. leptomerus J201 are 242.0 µg/mL, 550.4 µg/mL and 689.0 µg/mL, respectively, which suggest that the higher content of phenolic compounds in R. thindii J470 contributes to its radical scavenging properties. [ABSTRACT FROM AUTHOR]

The benefits of natural honeybee products (e.g., honey, royal jelly, beeswax, propolis, beevenom and pollen) to the immune system are remarkable, and many of them are involved in the induction of antibody production, maturation of immune cells and stimulation of the immune system. The type of plants in the geographical area, climatic conditions and production method have a significantly influence on the nutritional quality of honey. However, this variability can influence consumer liking by the sensory attributes of the product. The aim of this work was to compare the most popular honeys from Poland in terms of nutritional value, organoleptic properties and antioxidant activity. In the study, five varieties of honey (honeydew, forest, buckwheat, linden and dandelion) from conventional and organic production methods were tested. The nutritional characteristics of honey samples included acidity, content of water, sugars, vitamin C, HMF and phenolics (total and flavonoids), while honey color, taste, aroma and consistency were investigated in the organoleptic characteristics. The antioxidant activity was determined in water- and ethanol-soluble honey extracts using DPPH and ORAC tests. The results showed that organoleptic and nutritional characteristics of popular Polish honeys differ significantly in relation to plant source and production method. The significant effect of honey variety on the content of HMF, saccharose and phenolics, as well as acidity and antioxidant capacity were noted. The impact of variety and variety × production method interaction was significant in the case of the content of vitamin C, glucose and fructose. A visible difference of buckwheat and forest honeys from other samples was observed. The highest content of total phenolics with antioxidant activity based on the SET mechanism was found in buckwheat honeys, while forest honeys were richer in flavonoids. [ABSTRACT FROM AUTHOR]