Fenolne komponente i vitamin C kao izvori antioksidativne aktivnosti ploda crne ribizle (Ribes nigrum L.)

The content of some important phenolic compounds (kaempferol, myricetin, quercetin, and ellagic acid), total phenolics (TPH), vitamin C, and total antioxidant capacity (TAC) in the fruit of three black currant cultivars (Ben Lomond, Ben Sarek and Malling Juel) were studied. The content of individual phenolic compounds showed variability among the studied cultivars. The main flavonol found in cv. Malling Juel was kaempferol (1.60 μg g-1 FW), whereas the lowest values of myricetin (5.46 μg g-1 FW) and quercetin (7.65 μg g-1 FW) were also observed in the fruit of this cultivar. Ellagic acid content was the highest in cv. Ben Lomond (12.90 μg g-1 FW), which is also characterized by lower values of individual flavonols compared to other cultivars tested. However, the highest TPH level was recorded in cv. Ben Lomond (4.71 mg g-1FW). Vitamin C content in fruit of cv. Malling Juel was at a very high level (141.4 mg 100g-1), whereas cv. Ben Lomond expressed the highest level of TAC (7.60 mg asc g-1 FW). Overall, the content and profile of phenolic compounds in the black currant cultivars showed significant contribution to the expressed antioxidant capacity which was confirmed by positive correlation between TPH and TAC obtained in this study. Besides total phenolics, vitamin C is also a significant contributor to the measured antioxidant capacity in black currant fruit indicating that some cultivars with lower phenolic content may express high TAC.Rad prikazuje rezultate trogodišnjih ispitivanja sadržaja važnih fenolnih jedinjenja (flavonola - kampferola, miricetina i kvercetina, elaginske kiseline i ukupnih fenola), vitamina C, kao i vrednosti antioksidativnog kapaciteta registrovane u plodu tri sorte crne ribizle Ben lomond, Ben sarek i Moling džuel. Istraživanja su realizovana u periodu od 2004. do 2006. godine u laboratorijama Katedre za voćarstvo Poljoprivrednog fakulteta Univerziteta u Beogradu i Instituta za multidisciplinarna istraživanja iz Beograda. Ustanovljeno je variranje u sadržaju pojedinih individualnih fenolnih komponenti između ispitivanih sorti crne ribizle, pri čemu je kod sorte Moling džuel registrovan najveći prosečni sadržaj kampferola (1,60 μg g-1), ali i najniže prosečne vrednosti sadržaja miricetina (5,46 μg g-1) i kvercetina (7,65 μg g-1). Među ispitivanim sortama crne ribizle najveći sadržaj elaginske kiseline imala je sorta Ben lomond (12,90 μg g-1), koja se odlikuje nešto nižim vrednostima sadržaja flavonola u plodu, ali i najvećim sadržajem ukupnih fenola za ispitivani period (4,71 mg g-1). U pogledu sadržaja vitamina C, sorta Moling džuel je pokazala superiornost (141,4 mg 100g-1), dok se najvećim antioksidativnim kapacitetom ploda za trogodišnji period ispitivanja odlikuje sorta Ben lomond (7,60 mg ask g-1). Na osnovu većine analiziranih parametara može se konstatovati da sadržaj i profil fenolnih komponenata prisutnih u plodovima ispitivanih sorti crne ribizle, ima značajan doprinos u ispoljenoj antioksidativnoj aktivnosti, što potvrđuje i pozitivna korelativna zavisnost između sadržaja ukupnih fenola i antioksidativnog kapaciteta ploda. Pored ukupnih fenola, značajan doprinos antioksidativnom kapacitetu ploda daje i vitamin C. To objašnjava pojavu da su neke sorte posedovale visok antioksidativni kapacitet ploda uz, istovremeno registrovan, umeren sadržaj fenolnih jedinjenja

Određivanje odstojanja "S" između starih i novih tahimetrijsko snimljenih detaljnih tačaka

Određivanje odstojanja "S" između starih i novih tahimetrijsko snimljenih detaljnih tačaka

Određivanje odstojanja "S" između starih i novo tahimetrijsko snimljenih detaljnih tačaka

Određivanje odstojanja "S" između starih i novo tahimetrijsko snimljenih detaljnih tačaka

Određivanje odstojanja "S" između starih i novih tahimetrijsko snimljenih detaljnih tačaka

Određivanje odstojanja "S" između starih i novih tahimetrijsko snimljenih detaljnih tačaka

Određivanje odstojanja "S" između starih i novo tahimetrijsko snimljenih detaljnih tačaka

Određivanje odstojanja "S" između starih i novo tahimetrijsko snimljenih detaljnih tačaka

Effect of cadmium stress on antioxidative enzymes during the germination of Serbian spruce [Picea omorika (Pan..) Purkynĕ]

When considering the effect of heavy metals on trees generally and on forest ecosystems especially,  importance is given to their influence on seed germination in metal polluted soil. There is insufficient data on  this subject, especially when conifers are concerned. In this work, the influence of high cadmium  concentrations on percentage germination, specific activities and isoenzyme patterns of catalase (CAT),  superoxide dismutase (SOD), and peroxidase (POD) during the germination of Serbian spruce [Picea omorika (Pan..) Purkynĕ] was studied. Cadmium chloride concentrations of up to 0.1 mM did not cause an inhibition of germination, while 1 mM concentration inhibited germination and the activities of catalase, superoxide  dismutase and peroxidase. The isoenzyme profile of catalase and superoxide dismutase did not change at high cadmium concentrations, while peroxidase expression of basic peroxidase (B5) with pI value of 9.1 increased. This isoform of POD can play an important role in the early development of Serbian spruce and its defense mechanism against heavy metals.Key words: Seed germination, catalase, peroxidase, superoxide dismutase, heavy metals

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

The objective of this work was to evaluate the biochemical composition of six berry types belonging to Fragaria, Rubus, Vaccinium and Ribes genus. Fruit samples were collected in triplicate (50 fruit each) from 18 different species or cultivars of the mentioned genera, during three years (2008 to 2010). Content of individual sugars, organic acids, flavonols, and phenolic acids were determined by high performance liquid chromatography (HPLC) analysis, while total phenolics (TPC) and total antioxidant capacity (TAC), by using spectrophotometry. Principal component analysis (PCA) and hierarchical cluster analysis (CA) were performed to evaluate the differences in fruit biochemical profile. The highest contents of bioactive components were found in Ribes nigrum and in Fragaria vesca, Rubus plicatus, and Vaccinium myrtillus. PCA and CA were able to partially discriminate between berries on the basis of their biochemical composition. Individual and total sugars, myricetin, ellagic acid, TPC and TAC showed the highest impact on biochemical composition of the berry fruits. CA separated blackberry, raspberry, and blueberry as isolate groups, while classification of strawberry, black and red currant in a specific group has not occurred. There is a large variability both between and within the different types of berries. Metabolite fingerprinting of the evaluated berries showed unique biochemical profiles and specific combination of bioactive compound contents

Fizičko-hemijska i antioksidativna svojstva sorti i samoniklih vrsta rodova Fragaria i Rubus

The paper presents three years study results (2004-2006) of more important pomological properties and antioxidant capacity in the fruit of strawberry, raspberry and blackberry. A comparison was made between cultivars and wild relatives of each species (Fragaria vesca L., Rubus idaeus L., and Rubus fruticosus L.). It was found out that studied wild species expressed significantly lower values of physical fruit properties in comparison to those determined by commercial cultivars. With regard to chemical fruit composition, wild species showed better results for most of studied parameters. Total phenolics expressed higher values in the wild strawberry and blackberry in comparison to the studied cultivars, and consequently the highest levels of antioxidant capacity were recorded in F. vesca (5.78 mg g-1 FW), followed by R. fruticosus (4.95 mg g-1 FW). Concerning raspberries, the most widely grown cultivar in Serbia, 'Willamette', possessed higher antioxidant capacity than those for R. idaeus (1.41 mg ask g-1 FW). A positive correlation observed in this study between total phenolics and antioxidant capacity indicate the fact that phenolic compounds had significant contribution in expressed antioxidant activities.Rad prikazuje rezultate trogodišnjih ispitivanja važnijih pomoloških osobina i antioksidativnog kapaciteta ploda, koji su komparativno proučavani kod samoniklih vrsta jagodastih voćaka: šumske jagode (Fragaria vesca L.), samonikle maline (Rubus idaeus L.) i samonikle kupine (Rubus fruticosus L.) uzetih sa prirodnih staniš ta i kod dve komercijalno značajne sorte svake pomenute vrste: jagode (Marmolada i Madlen), maline (Willamette i Meeker) i kupine (Thornfree i Čačanska bestrna). Ustanovljeno je da su među fizičkim osobinama ploda, značajno niže vrednosti mase i dimenzija ploda ispoljile ispitivane samonikle vrste jagodastih voćaka u poređenju sa komercijalnim sortama, dok su u pogledu hemijskog sastava ploda kod većine analiziranih parametara samonikle vrste pokazale superiornost. Rezultati sadržaja ukupnih fenola i antioksidativnog kapaciteta ploda ukazuju da su šumska jagoda (4,69 mg g-1 i 5,78 mg g-1) i samonikla kupina (3,20 mg g-1 i 4,95 mg g-1) ispoljile statistički značajno veće vrednosti u poređenju sa komercijalnim sortama. Izuzetak predstavlja samonikla malina kod koje je antioksidativni kapacitet ploda ispoljio nižu prosečnu vrednost (1,41 mg g-1) u poređenju sa sortom Willamette (3,13 mg g-1). Pozitivna linearna korelacija registrovana između sadržaja ukupnih fenola i antioksidativnog kapaciteta ploda ukazuje na činjenicu da su fenolna jedinjenja imala značajan doprinos u ispoljenoj antioksidativnoj aktivnosti

Maternal effect of continuous light on seed properties in a short day plant Chenopodium rubrum L. (Chenopodiaceae)

Environmental effects on morphological and physiological properties of offspring which occurs during development of mother plant are called maternal environmental effects. Photoperiod is one of the crucial environmental factors according to which plants modify numerous physiological processes. Maternal effect of photoperiod in a short day plant Chenopodium rubrum extends through the whole life cycle of offspring and persist to the second generation, photoperiod during induction and evocation of flowering of mother plants showing the key influence. Here we show that also non-inductive photoperiod preceding flowering induction of mother plants shows its maternal effect on offspring properties: seed size, seed germination and seed protein composition. Presented data argues in favor of earlier suggested that relative amounts of seed proteins represent an “archive“ of photoperiods experienced by mother plants during their lives

Can glial cells save neurons in epilepsy?

Epilepsy is a neurological disorder caused by the pathological hyper-synchronization of neuronal discharges. The fundamental research of epilepsy mechanisms and the targets of drug design options for its treatment have focused on neurons. However, approximately 30% of patients suffering from epilepsy show resistance to standard anti-epileptic chemotherapeutic agents while the symptoms of the remaining 70% of patients can be alleviated but not completely removed by the current medications. Thus, new strategies for the treatment of epilepsy are in urgent demand. Over the past decades, with the increase in knowledge on the role of glia in the genesis and development of epilepsy, glial cells are receiving renewed attention. In a normal brain, glial cells maintain neuronal health and in partnership with neurons regulate virtually every aspect of brain function. In epilepsy, however, the supportive roles of glial cells are compromised, and their interaction with neurons is altered, which disrupts brain function. In this review, we will focus on the role of glia-related processes in epileptogenesis and their contribution to abnormal neuronal activity, with the major focus on the dysfunction of astroglial potassium channels, water channels, gap junctions, glutamate transporters, purinergic signaling, synaptogenesis, on the roles of microglial inflammatory cytokines, microglia-astrocyte interactions in epilepsy, and on the oligodendroglial potassium channels and myelin abnormalities in the epileptic brain. These recent findings suggest that glia should be considered as the promising next-generation targets for designing anti-epileptic drugs that may improve epilepsy and drug-resistant epilepsy.kategorija casopsisa M2