Evaluation of secondary metabolites, antioxidant activity, and color parameters of Nepali wines

Oxidative Stress and Antioxidants-A Critical Review on In Vitro Antioxidant Assays

Antioxidants have been widely studied in the fields of biology, medicine, food, and nutrition sciences. There has been extensive work on developing assays for foods and biological systems. The scientific communities have well-accepted the effectiveness of endogenous antioxidants generated in the body. However, the health efficacy and the possible action of exogenous dietary antioxidants are still questionable. This may be attributed to several factors, including a lack of basic understanding of the interaction of exogenous antioxidants in the body, the lack of agreement of the different antioxidant assays, and the lack of specificity of the assays, which leads to an inability to relate specific dietary antioxidants to health outcomes. Hence, there is significant doubt regarding the relationship between dietary antioxidants to human health. In this review, we documented the variations in the current methodologies, their mechanisms, and the highly varying values for six common food substrates (fruits, vegetables, processed foods, grains, legumes, milk, and dairy-related products). Finally, we discuss the strengths and weaknesses of the antioxidant assays and examine the challenges in correlating the antioxidant activity of foods to human health.

Biochemical Traits, 1H NMR Profile and Residual DNA Content of ‘Asprinio’, White Wine from Campania Region (Southern Italy)

‘Asprinio’ is a white dry wine characteristic for its acidity and aromatic flavour, known as emerging DOP wine in Southern Italy. Nevertheless, little information is available on the metabolomic profile of this wine. Thus, in this paper we evaluated the colourimetric parameters, ¹H NMR profiles and free amino acids content of ‘Asprinio’ wines, bottled by two different wineries (hereafter ‘Asprinio_A’ and ‘Asprinio_B’) collected in 2019 and 2020, using ‘Greco di Tufo’ for comparison. The colourimetric parameters are similar for both ‘Asprinio’ wines and differ from ‘Greco di Tufo’ wines. On the other hand, both ¹H NMR and free amino acid content profiles show different chemometric profiles among the three wines analysed, although the profiles are similar for both vintages. Moreover, the multivariate analyses carried out highlight differences between ‘Asprinio_A’ and ‘Asprinio_B’, which exbibit also different residual yeast and plant DNA. Overall, considering that the two-manufacturing wineries use 100% ‘Asprinio’ grape, the difference retrieved between the two ‘Asprinio’ wines could be explained by the different grapevine training systems: ‘vite maritata’ (training system inherited from Etruscans) for ‘Asprinio_A’ and ‘guyot’ for ‘Asprinio_B’.

Determination of Antiradical Activity, Total Phenolic, and Total Flavonoid Contents of Extracts and Fractions of Langsat (Lansium domesticum Coor.) Seeds

Lansium domesticum Coor. is a fruit species from the Meliaceae family, which is a tropical plant native to Southeast Asia. Local citizens call it langsat, longkong, or duku and have used it as traditional medicine. The seeds of L. domesticum are used as a fever medicine, its bark is used to treat scorpion sting, and its leaves are used to repel mosquitoes. Because of its various uses, it is necessary to explore the antiradical potential of L. domesticum seeds. This study aims to determine the antiradical potential of L. domesticum seeds extract and fractions by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and to discover compounds that act as antiradical. Lansium domesticum seed powder was macerated with methanol, and then the extract was concentrated using a rotary evaporator and fractionated by n-hexane and ethyl acetate. The antiradical assay was conducted on extract and fractions by using DPPH radicals. Phenolic and flavonoid contents from extract and fractions were also tested. The ethyl acetate fraction obtained strong antiradical potential with an IC50 value of 8.938 � 0.031 �g/mL. Total phenolic and flavonoid contents of ethyl acetate fraction were higher with values ??of 58.25 � 0.501 mgGAE/g sample and 75.123 � 0.175 mgQE/g sample, respectively. Correlation of phenolic and flavonoid contents, which inhibited radicals had R2 values ??of 0.9182 and 0.7658. Ethyl acetate fraction of L. domesticum seeds had very strong antiradical activity. Further isolation is expected to be conducted to discover which compounds are the most responsible as antiradical.