Andreea Stănilă

Bioactive compounds and antioxidant activity of Rosa canina L. biotypes from spontaneous flora of Transylvania

BackgroundThe theoretical, but especially the practical values of identifying the biochemical compounds from the Rosa canina L. fruits are of present interest, this aspect being illustrated by the numerous researches. It was reported that the Rosa canina L. fruit, with its high ascorbic acid, phenolics and flavonoids contents, have antioxidant, antimutagenic and anticarcinogenic effects.This study was performed on order to evaluate the amount of the main phytochemicals (vitamin C, total polyphenols, and total flavonoids) content and their antioxidant activity.ResultsThe results obtained revealed that the average amounts of vitamin C within the studied genotypes were: 360.22 mg/100 g frozen pulp (var. transitoria f. ramosissima, altitude 1250 m) and 112.20 mg/100 g frozen pulp (var. assiensis, altitude 440 m), giving a good correlation between the vitamin C content of the rosehip and the altitude. The total polyphenols content varied from 575 mg/100 g frozen pulp (var. transitoria f. ramosissima) to 326 mg/100 g frozen pulp (var. lutetiana f. fallens). The total flavonoids content showed the highest value for var. assiensis variant 163.3 mg/100 g frozen pulp and the lowest value attributed to var. transitoria f. montivaga 101.3 mg/100 g frozen pulp. The antioxidant activity of eight rose hip extracts from wild Transylvania populations was investigated through DPPH method. The antioxidant activity revealed a good correlation only with vitamin C content and total polyphenols.ConclusionEight Rose hip fruit species were compared taking into consideration the ascorbic acid, total polyphenols, total flavonoids contents and their antioxidant activity. Based on these results, two of the rosehip genotypes that were analysed could be of perspective for these species’ amelioration, due to their content of phytochemicals mentioned above. These varieties are var. transitoria f. ramosissima (Bistrita-Nasaud, Agiesel) and var. transitoria f. montivaga (Bistrita-Nasaud, Salva) which can be used as a potential source of natural antioxidants.

Effects of Extraction Solvents on the Quantification of Free Amino Acids in Lyophilised Brewer’s Yeast

The aim of this work was to test some solvents in order to improve the free amino acids extraction from lyophilised brewer’s yeast. The brewer’ yeast was treated with four types of extraction solvents: Solvent I – acetonitrile 25%/HCl 0.01M (ACN); Solvent II – ethanol 80%; solvent III – HCl 0.05M/deionized water (1/1 volume); Solvent IV – HCl 0.05M/ethanol 80% (1/1 volume). The supernatants were analysed by HPLC-DADESI-MS method. Acetonitrile provided the less quantities and number of amino acids extracted due to its weaker polarity. Solvent II and IV (ethanol, respectively acidified ethanol), which have an increased polarity, extracted 15 amino acids due to the addition of HCl in solvent IV. Solvent III (acidified water) proved to be the best extraction solvent for the amino acids from brewer’s yeast providing the separation of 17 compounds: GLN, ASN, SER, GLY, ALA, ORN, PRO, HIS, LYS, GLU, TRP, LEU, PHE, ILE, AAA, HPHE, TYR.

Nitrates in Food, Health and the Environment

Over the last 25 years, many national and international agencies have been concerned with pollution of the Romanian environment, particularly in soil andwater, food (such as animal and plant products), and its impact on human health. Contamination with nitrates due to an overloading of soil with fertilizers, especially before 1989, combined with an inappropriate management of animal waste (rich in organic nitrogen), resulted in a cascade of problems with food safety and health. An examination of such events and conflicts associated with nitrate contamination in Romania over the last 20 years and solutions to this problem, from different national and international studies, are presented here. The European Union’s Council Directive 91/676/EEC Official Journal, 1991, known as the Nitrates Directive, was formulated to prevent health and ecological problems resulting from farm practices. This EU Directive, which also includes the Code for Good Agricultural Practices, is being implemented at a national level as part of a national strategy for reducing Romania’s impact on environmental pollution.