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The objective of this study was to determine and compare the content of total anthocyanins (TACY), total phenolics (TPC) and total antioxidant activity (TAA) of the fruit of 'Bluecrop' highbush blueberry grown under different nutrient management practices in a soilless production system. A field study was carried out in a highbush blueberry plantation situated near Belgrade (Serbia), during the period of 2016-2017. The orchard was planted in the spring of 2016 in 50 l polypropylene pots with 5-year-old nursery plants. Each pot was filled with the mix of pine sawdust (60%), white peat (30%) and perlite (10%), and placed at a distance of 0.8 m within the row and 3.0 m between the rows (4,170 bushes ha-1 ). The following fertilizer treatments were evaluated: 1. organic fertilizers (Org); 2. mineral fertilizers (Min) and 3. a combination of organic and mineral fertilizers (Org-Min). Soluble NPK fertilizers were applied with irrigation water, whereas granulated mineral and pelleted organic fertilizers were mixed with the substrate. Fruit samples were collected in triplicate at the beginning of ripening, full maturity and the end of the harvest season. No significant effect of harvest time on each of the tested parameters was observed, whereas the content of TACY did not even differ under various fertilizer treatments. TPC in the fruit significantly increased in Org and Org-Min treatments (139.8 and 139.3 mg eq GA 100 g-1 FW, respectively) compared to Min treatment (122.7 mg eq GA 100 g-1 FW), while a considerably high TAA level was found only in berries under Org-Min treatment (0.53 mg asc g-1 FW). Cilj ovog istraživanja bio je da se odredi i uporedi sadržaj ukupnih antocijana i ukupnih fenola, kao i antioksidativna aktivnost u plodu sorte visokožbunaste borovnice 'Bluecrop' gajene u supstratu pod uticajem različitih načina ishrane. Poljsko istraživanje je izvedeno u proizvodnom zasadu borovnice koji se nalazi u blizini Beograda (Srbija), tokom perioda 2016-2017. godine. Zasad je podignut u proleće 2016. godine sadnjom petogodišnjih biljaka u saksije od polipropilenske folije zapremine 50 l. Svaka saksija je ispunjena supstratnom smešom sastavljenom od strugotine četinara (60%), belog treseta (30%) i perlita (10%). Primenjeno rastojanje sadnje je 0,8 m u redu i 3,0 m između redova (4.170 žbunova po ha). Ispitivana je primena sledećih đubriva: 1. organska đubriva (Org); 2. mineralna đubriva (Min) i 3. kombinovana primena organskih i mineralnih đubriva (OrgMin). Rastvorljiva NPK đubriva su primenjivana kroz sistem za navodnjavanje, dok su granulisana mineralna i peletirana organska đubriva mešana sa supstratom. Uzorci plodova su uzimani u 3 ponavljanja na početku, sredini i na kraju sezone berbe. Vreme berbe nije ispoljilo značajan uticaj na testirane parametre, dok se sadržaj ukupnih antocijana nije razlikovao čak ni pod uticajem primenjenih đubriva. Sadržaj ukupnih fenola u plodu bio je značajno povećan u Org i Org-Min tretmanima (139,8, odnosno 139,3 mg ekv. gal. kis./100 g sv.m.pl.), dok je značajno veća ukupna antioksidativna aktivnost ustanovljena u plodovima iz OrgMin tretmana (0,53 mg ask./g sv.m.pl.).

A heterotrophic model system was established in our studies in order to differentiate the effect of high salt concentrations in external medium on growth and sugar metabolism in roots from the effect of reduced sugar availability resulting from decreased photosynthesis under salinity. Soluble sugar content and the activity of acid invertase in root cultures of salt-tolerant (ST) and salt-sensitive (SS) Schenkia spicata (L.) Mansion genotypes were investigated during exposure to different NaCI concentrations (0-200 mM). Their response to severe salinity was characterized by a metabolic adjustment that led to the accumulation of sucrose (Suc) in root tissues. There was clear evidence that cell wall invertase (CW-Inv) is, the major contributor to the Suc/hexose ratio in roots during exposure to elevated salinity. The results of CW-Inv activity and immunodetection assays in our study suggest that the regulation of CW-Inv expression is most likely achieved in a salt stress dependent manner. Also, NaCI modulated soluble acid invertase (SA-Inv) expression differentially in SS and ST genotypes of S. spicata. Regardless of the salt treatment, genotype, or the amount of enzyme, SA-Inv activity was generally low, indicating regulation at the posttranslational level. The results suggest no direct role of SA-Inv in the regulation of the root tissue carbohydrate pool and therefore in the control of the availability of glucose and fructose for the primary metabolism and/or osmotic adjustment in the present heterotrophic model system, 2012 Elsevier GmbH. All rights reserved. Serbian Ministry of Education and Science [173024, 173028, 173040]

Ganoderma lucidum is a well-known medicinal mushroom species in which polysaccharides are one of the major sources of biological activity. The species was considered as a species-complex due to significant variations in morphological, biochemical, and genetic features among populations with a worldwide distribution. This fact was the basis for setting the aim of this research: to study intraspecific diversity in polysaccharide production and intracellular sugar composition among selected G. lucidum strains. The presence of intraspecific diversity among 10 G. lucidum strains, from different areas worldwide, was noted. Values of produced mycelia biomass and intracellular polysaccharides were found in wide ranges (3.1-28.2 g L-1 and 20.0-53.3 mg g(-1), respectively), while differences in extracellular polysaccharide amounts were minor (0.2-1.5 mg mL(-1)). The significant quantitative and qualitative differences in intracellular sugar composition were noted. Glucose was the predominant sugar in almost all strains except one (HAI 447), where sucrose was dominant. The potential of polysaccharide production and intracellular sugar composition could be one more taxonomic criterion for strain characterization within G. lucidum. The differences in intracellular sugar composition and proportions could be reflected in features of produced polysaccharides and also in their biological activities. Ministry for Science and Technological Development of Serbia [173032, 173040]

Anticancer activities of various extracts of the medicinal mushroom, Ganoderma lucidum, have been widely demonstrated and are mainly associated with the presence of different bioactive polysaccharides and triterpenoids. We have evaluated and compared in vitro and in vivo the antitumor effects of two preparations from Ganoderma lucidum: a methanol extract containing total terpenoids (GLme) and a purified methanol extract containing mainly acidic terpenoids (GLpme). Both extracts inhibited tumor growth of B16 mouse melanoma cells inoculated subcutaneously into syngeneic C57BL/6 mice and reduced viability of B16 cells in vitro, whereby GLme exhibited stronger effect. Furthermore, anticancer activity of GLme was demonstrated for the first time against two other rodent tumor cell lines, L929-mouse fibrosarcoma and C6-rat astrocytoma. The mechanism of antitumor activity of GLme comprised inhibition of cell proliferation and induction of caspase-dependent apoptotic cell death mediated by upregulated p53 and inhibited Bcl-2 expression. Moreover, the antitumor effect of the GLme was associated with intensified production of reactive oxygen species, whereas their neutralization by the antioxidant, N-acetyl cysteine, resulted in partial recovery of cell viability. Thus, our results suggest that GLme might be a good candidate for treatment of diverse forms of cancers. Serbian Ministry of Science [143029, 143016]

A wide range of sucrose, fructose, and glucose levels in culture media was tested in vitro in order to determine those that provide optimum growth, morphogenesis, and the production of secondary metabolites in Nepeta rtanjensis Diklic and Milojevic shoots. The effect of different concentrations of the carbohydrates in culture media on the internal carbohydrate status of N. rtanjensis shoots was also determined. Our results show that in vitro growth and development of N. rtanjensis, as well as nepetalactone accumulation, are significantly affected by both the type of carbohydrate and its concentration in the culture medium. Glucose proved to be the most efficient carbon and energy source. null