Jasminka Milivojevic

Classification and fingerprinting of different berries based on biochemical profiling and antioxidant capacity

O objetivo deste trabalho foi avaliar a composicao bioquimica de seis especies de pequenas frutas dos generos Fragaria, Rubus, Vaccinium e Ribes. As amostras das frutas foram coletadas em triplicata (com 50 frutas cada) de 18 diferentes especies ou cultivares dos generos mencionados, durante tres anos (2008 a 2010). Os teores individuais de acucares, acidos orgânicos, flavonois e acidos fenolicos foram determinados por cromatografia liquida de alta performance (HPLC), e os fenois totais (FT) e a capacidade antioxidante total (CAT), por meio de espectrofotometria. As analises de componente principal (ACP) e de agrupamento hierarquico (AH) foram utilizadas para avaliar as diferencas no perfil bioquimico das frutas. Os maiores teores de compostos bioativos foram encontrados em Ribes nigrum e em Fragaria vesca, Rubus plicatus e Vaccinium myrtillus. ACP e AH foram capazes de discriminar parcialmente as frutas com base em sua composicao bioquimica. Os acucares totais e individuais, a miricetina, o acido elagico, FT e CAT foram os parâmetros que mais impactaram na avaliacao da composicao bioquimica das pequenas frutas. AH fez a separacao de amora-preta, framboesa e mirtilo como grupos isolados, porem a classificacao do morango, da groselha-preta e da groselha-vermelha, em um grupo especifico, nao ocorreu. Ha grande variabilidade entre e dentro dos diferentes tipos de frutas vermelhas. A identificacao de metabolitos das pequenas frutas mostrou perfis bioquimicos unicos e combinacoes especificas de teores de compostos bioativos.

Sugar and organic acids profile in the fruits of black and red currant cultivars.

In this study, three black currant cultivars (Ben Sarek, Ben Lomond and Malling Juel) and three red currant cultivars (Industrija, Rondom and Red Versailles) were compared in terms of fruit quality by high-performance liquid chromatography analysis in order to determine sugars and organic acids profiles in their fruits. Among the analysed individual sugars, fructose was determined to be the major component in all studied cultivars. Cv Ben Lomond exhibited the highest levels of glucose (78,8 mg g-1 FW), fructose (117,6 mg g-1 FW) and sucrose (10,1 mg g-1 FW) in comparison to the other tested black currant cultivars. Among investigated red currant cultivars the highest amounts of glucose (81,1 mg g-1 FW), fructose (113,1 mg g-1 FW) and sucrose (14,5 mg g-1 FW) were recorded in the fruits of cv Industrija, as well as the richest content of total sugars (208,7 mg g-1 FW). The same tendency was noticed considering the organic acids content (citric and malic), that is, the highest levels were registered with the cv Industrija (0,32 mg g-1 FW and 0,13 mg g-1 FW, respectively). Black currant cv Ben Sarek displayed the highest contents of citric and malic acids (0,68 mg g-1 FW and 0,14 mg g-1 F, respectively). Generally, dominant share of total acids was exhibited by citric acid in all studied black and red currant cultivars. These results point to the fact that the chemical fruit composition of currants significantly varied among the genotypes of each species analysed. .

How to improve strawberry productivity, nutrients composition, and beneficial rhizosphere microflora by biofertilization and mineral fertilization?

Abstract The main objective of this study was to investigate and compare the effects of fertilizer types on the counts of soil microorganisms, the mineral leaf composition, and productivity of three strawberry cultivars in the period 2012–2013. Two types of fertilizers were applied—mineral and microbiological. Significantly higher number of Azotobacter, ammonifiers, oligonitrophils, and total microbial count were observed under biofertilizers treatment. Significantly higher counts of fungi and actinomycetes were obtained under mineral fertilizer treatment, compared to other fertilizer treatments. The use of mineral fertilizer led to the most favorable balance of macronutrients and micronutrients in the leaf. In 2012, the generative potential and yield increased after mineral fertilization, whereas in 2013 these parameters were positively affected by mineral fertilizer and Biofertilizer 1. Given the obtained results, in order to improve technology of strawberry production, a partial substitution of mineral fertilizers by microbiological ones can be recommended.

Effect of Prohexadione-Ca and young canes removal on physiological characteristics of leaf and fruit in raspberry cultivar ‘Willamette’

The research was designed to evaluate the effect of growth regulator Prohexadione-Ca (ProCa) and young canes removal on the changes of photosynthetic pigment content and modification activities of antioxidant enzyme defense system in leaves and fruits of raspberry cultivar ‘Willamette’ (Rubus idaeus L.). The experiment was performed in the period of 2011-2012. It consisted of five treatments: control - no treatment; 2ProCa - with 2 ProCa applications; Z - one removal of young canes; Z+2ProCa - young canes removal with 2 ProCa applications; 2Z - two removals of young canes. The first series of young canes were removed for the first time in mid-April and for the second time at the begining of May. In 2ProCa and Z+2ProCa treatments foliar application of ProCa was carried out twice during the period of April-May in interval of three weeks, i.e. when the primocane growth reached 30 cm in height. The following concentrations of ProCa: 125 ppm (first application) and 200 ppm (second application) were applied. Significantly higher mean values of chlorophyll b content were registered in the 2ProCa (42.84 μg•g-1 FW) and Z+2ProCa (46.12 μg•g-1 FW) treatment. The highest SOD and POD activities were found in leaves of new young canes which developed after the young canes removal was applied. Z+2ProCa treatment significantly increased CAT activity in raspberry leaves (63.51 U mg-1 prot.). Both of implemented measures, especially applied in combination, resulted in higher activity of CAT, POD and SOD enzymes in the fruits of the examined cultivar. [Projekat Ministarstva nauke Republike Srbije, br. 46008 i br. 173040]