45 research outputs found
Ispitivanje nekih funkcionalnih svojstava mesa tolstolobika (Hypophthalmichthys molitrix Val.) i šarana Cyprinus carpio Lin
Water binding ability (WBA), held water (HW) and gel-forming properties of silver carp (Hypophthalmichthys molitrix Val) and carp (Cyprinus carpio Lin) meat were examined in this paper. Two variants of fish meat gels: A with 50% of meat and B with 60% of meat were examined at temperatures: 70 75, 80, 85 and 90°C. The variant A of silver carp meat gels has shown the maximum of WBA and HW at 80 oC, and the variant B at 75°C. In both variants of carp meat gels slow increase of WBA and HW with rise of temperature to 80°C was established. Silver carp meat gels have had better WBA than control gels (beef and poultry meat), and carp meat gels have better HW, but somewhat worse WBA than control gels. In gels of variant A of silver carp meat the highest module of elasticity (6.862 N/cm2) was found at thermal treatment at 85°C, but statistically significant differences in relation to other temperatures were not established. In variant B, with the rise of temperature, the module of elasticity increases; statistically significant differences were established among gels treated at 70 oC and others. Differences between variants A and B were statistically significant at all examined temperatures. Meat gels of silver carp have significantly lower module of elasticity compared to control gels. Under conditions of our experiment the module of elasticity of carp meat was below measuring limit.Nekonvencionalni tehnološki procesi, u preradi ribe, postaju sve zastupljeniji zahvaljujući mogućnostima koje pružaju u pogledu asortimana i racionalnom (ekonomičnom) iskorišćenju sirovine, i baziraju se na usitnjenom ribljem mesu ili surimiju kao sirovini. Kvalitet finalnog proizvoda uslovljen je funkcionalnim karakteristikama sirovine, kao što su sposobnost vezivanja vode i sposobnost geliranja i/ili uslovima toplotnog procesa. U ovom radu ispitivane su sposobnost vezivanja vode (SVV) i zadržavanja vode (HW) i sposobnost geliranja mesa belog tolstolobika (Hypophthalmichthys molitrix Val) i šarana (Cyprinus carpio Lin). SVV, HW i sposobnost geliranja varijanti gelova sa 50 i 60% mesa (A i B) ispitivane su na temperaturama: 70, 75, 80, 85 i 90°C. Varijanta A gelova od mesa tolstolobika pokazuje maksimalnu SVV i HW na 80°C, a varijanta B na 75°C. Obe varijante gelova od mesa šarana pokazuju blago povećanje SVV i HW sa porastom temperature do 80oC. Gelovi od mesa tolstolobika pokazuju znatno bolju SVV od kontrolnih gelova (goveđe i pileće meso), a gelovi od mesa šarana bolju HW, ali nešto lošiju SVV od kontrolnih gelova. Kod varijante gelova A od mesa tolstolobika najveći modul elastičnosti 6.862 N/cm2 utvrđen je pri toplotnoj obradi na 85oC, međutim, nisu utvrđene i statistički značajne razlike u odnosu na ostale temperature. Kod varijante B, sa povećanjem temperature povećava se i modul elastičnosti, statistički značajne razlike utvrđene su između gelova tretiranih na 70°C, i ostalih. Razlike između varijanti A i B su statistički značajne na svim ispitivanim temperaturama. Gelovi od mesa tolstolobika imaju statisički značajno manji modul elastičnosti, u odnosu na kontrolne gelove
Physiological and phytochemical characterization of plant species Rindera umbellata (Waldst. & Kit.) Bunge cultivated in vitro
Rindera umbellata је ретка и крајње угрожена биљна врста у Србији. Да би се успоставили протоколи за ex situ заштиту и обезбедио материјал за молекуларне и фитохемијске анализе успостављена је in vitro култура ове слабо испитане врсте. Оптимизација услова гајења заснивала се на варирању врсте и концентрације угљених хидрата (сахароза, глукоза и фруктоза) и фитохормона (гиберелна и јасмонска киселина) у подлози за гајење. Такође је испитиван утицај наведених регулатора растења на продукцију фармацеутски важних секундарних метаболита. In vitro растење и развиће биљака врсте R. umbellata је под утицајем како врсте, тако и концентрације примењеног шећера. Утврђено је да сахароза представља најбољи извор угљеника за in vitro раст, ожиљавање и аклиматизацију биљака, а да су концентрације од 0,3 и 1 М свих примењених шећера инхибиторне. Гиберелна киселина стимулише раст и издуживање стабла ових розетастих биљака, али не утиче значајно на процес ожиљавања. Јасмонска киселина је стимулисала in vitro раст и ожиљавање R. umbellatа, нарочито при нижим концентрацијама и на краткотрајним третманима. Највиша примењена концентрација овог фитохормона (200 μМ) инхибирала је све посматране процесе. Уочена су значајна варирања у квантитативном и квалитативном садржају секундарних метаболита зависно од начина гајења, фенофазе и тестираног биљног органа. Биљке врсте R. umbellata у природним условима синтетишу незасићене и засићене пиролизидинске алкалоиде. Биљке гајене in vitro синтетишу веома ниске концентрације искључиво засићених пиролизидинских алкалоида.
Фенолна једињења детектована су у листовима и корену ових биљака. Од фенолних киселина биљке из природе садрже више рузмаринске киселине у надземним деловима, док је садржај литоспермичне киселине Б у кореновима вишеструко већи од количине рузмаринске киселине. Сличан однос садржаја ових једињења запажен је и у биљкама које су гајене у in vitro култури. Иако су највише примењене концентрације сахарозе биле инхибиторне за растење, биљке при овим условима синтетишу највише фенолних једињења, флавоноида и рузмаринске киселине...Rindera umbellata is a rare and critically endangered plant species in Serbia. In order to optimize protocols for ex situ conservation and provide the materials for molecular and phytochemical analysis, a suitable method for in vitro propagation of this plant species was established. Optimization of the growing conditions was based on varying the type and concentration of carbohydrates (sucrose, glucose and fructose) and phytohormones (gibberellic acid and jasmonic acid) in the substrate. Furthermore, the effect of selected growth regulators on the production of pharmaceutically important secondary metabolites was investigated. In vitro growth and development of R. umbellata plants were significantly affected by both the type and the concentration of applied sugars. It was found that sucrose is the best carbon source for in vitro growth, rooting and acclimatization of the plants, and that the concentrations of 0.3 and 1 M of all applied sugars had an inhibitory effect. Gibberellic acid stimulated growth and stem elongation, but did not significantly affect the process of rooting. Jasmonic acid stimulated in vitro growth and rooting of R. umbellata, especially at lower concentrations, and after short-term treatments. Significant variations in quantitative and qualitative contents of secondary metabolites are noticed, which depended on the method of cultivation, growth stages and plant organs tested. Plants of R. umbellata grown under natural conditions synthesized both unsaturated and saturated pyrrolizidine alkaloids. In vitro grown plants synthesized a very low concentration of saturated alkaloids.
Phenol compounds were detected in the leaves and roots of the plants. The content of lithospermic acid B in the roots was several times greater than the amount of rosmarinic acid. A similar relation between the contents of rosmarinic acid and lithospermic acid B was observed in plants that were grown in vitro. Gibberellic acid did not affect the production of phenolic compounds in the shoots. However, total phenol content in roots increased, while the concentration of flavonoids, rosmarinic acid and lithospermic acid B decreased in relation to increasing concentrations of gibberellic acid..
Sensitivity of gypsy moth neurosecretory neurons to acute thermal stress
In gypsy moth caterpillars exposed to a temperature of 35°C (for 1, 12 and 24 h and caterpillars that were exposed to elevated temperature for 12 h and were allowed to recover for 12 h at 23°C), changes in the brain protein profiles and morphometric characteristics of A1’ medial and L2 lateral protocerebral neurosecretory neurons were analyzed. In all groups, protein bands with a molecular mass corresponding to that of members of heat-shock protein families were detected, indicating that acute exposure to this temperature likely induced the synthesis of HSP. Increased morphometric parameters of A1’ neurons and the large amount of neurosecretory material in the neuron body implicate that the temperature of 35°C is not in the temperature range that exerts stimulatory effects on growth and survival. Changes in the morphometric characteristics of L2 neurosecretory neurons from the lateral part of the protocerebrum, and retention of neurosecretory material in their cytoplasm indicate a low level of secretion
Biogenic amines in protocerebral A2 neurosecretory neurons of Lymantria dispar L. (Lepidoptera:Lymantriidae): Response to trophic stress
The number, morphometric parameters and amount of aminergic neurosecretory product of protocerebral A2 neurosecretory neurons were investigated in the fifth instar of Lymantria dispar caterpillars, following a suitable or unsuitable trophic regime. Caterpillars originated from two populations (Quercus rubra or Robinia pseudoacacia forest) and were differently adapted to trophic stress, i.e. feeding on locust tree leaves - unsuitable host plant. The number of neurosecretory neurons was higher in the caterpillars originated from Robinia population than in Quercus population, regardless of feeding. A2 neurosecretory neurons, nuclei and their nucleoli were larger in caterpillars fed with unsuitable leaves in both populations. There was more aminergic product in the A2 neurosecretory neurons of the caterpillars fed with unsuitable leaves independently of population origin
The influence of increased rearing density on medial protocerebral neurosecretory neurons of Lymantria dispar L. caterpillars
Morphometric changes of A1, A1' and A2 protocerebral dorsomedial neurosecretory neurons, total brain protein content and brain protein profiles were analyzed in 4th instar Lymantria dispar larvae under elevated rearing density, i.e. under intense stress when 5 larvae were kept in a petri dish (V = 80 ml), less intense stress when 5 larvae were kept in a plastic cup (V = 300 ml). In the control samples the larvae were reared in isolated conditions. Protein pattern changes in the brain were observed. Proteins with the following molecular masses: 30, 14, 10 and 3.4-2.5 kD were detected in the experimental groups. The size and cytological characteristics of protocerebral dorsomedial neurosecretory neurons were changed under elevated rearing density.U ovom radu je ispitivan uticaj povećane gustine gajenja na gusenice gubara Lymantria dispar L. Morfometrijske promene A1, A1' i A2 dorzomedijalnih neurosekretnih neurona protocerebruma, ukupna količina proteina u homogenatima mozga i proteinski profili mozga gusenica gubara 4. larvenog stupnja su ispitivani pod sledećim eksperimentalnim uslovima: intenzivan stres - 5 larvi je gajeno u petri šolji (V = 80 ml), manje intenzivan stres - 5 larvi je gajeno u plastičnim čašama (V = 300 ml) i kontrola - larve su gajene pojedinačno, u izolovanim uslovima. U proteinskim profilima promene su uočene u sledećim regionima molekulskih masa: 30, 14, 10, 3.4-2.5 kD. Veličina i citološke osobine protocerebralnih dorzomedijalnih neurosekretnih neurona se menjaju pod delovanjem povećane gustine gajenja.Projekat ministarstva br. 14303
Sensitivity of gypsy moth neurosecretory neurons to acute thermal stress
In gypsy moth caterpillars exposed to a temperature of 35°C (for 1, 12 and 24 h and caterpillars that were exposed to elevated temperature for 12 h and were allowed to recover for 12 h at 23°C), changes in the brain protein profiles and morphometric characteristics of A1' medial and L2 lateral protocerebral neurosecretory neurons were analyzed. In all groups, protein bands with a molecular mass corresponding to that of members of heat-shock protein families were detected, indicating that acute exposure to this temperature likely induced the synthesis of HSP. Increased morphometric parameters of A1' neurons and the large amount of neurosecretory material in the neuron body implicate that the temperature of 35°C is not in the temperature range that exerts stimulatory effects on growth and survival. Changes in the morphometric characteristics of L2 neurosecretory neurons from the lateral part of the protocerebrum, and retention of neurosecretory material in their cytoplasm indicate a low level of secretion.Projekat ministarstva br. 17302
The response of dorsomedial A1' and dorsolateral L2' neurosecretory neurons of Lymantria dispar L. caterpillars to the acute effects of magnetic fields
The morphometric changes (size of neurons and their nuclei) of protocerebral dorsomedial A1' and dorsolateral L2' neurosecretory neurons were analyzed in Lymantria dispar larvae after exposure to strong static (SMF, 235 mT) and extremely low frequency magnetic fields (ELF MF, 2 mT). Increase in the size of A1' neurons and their nuclei were observed after acute exposure to SMF. Decrease in the size of these neurons and their nuclei was observed after exposure to ELF MF. The size of L2' neurons and their nuclei tend to decrease after exposure to SMF and ELF MF. The quantification of protein bands within the Mr range corresponding to the large form of the prothoracicotropic neurohormone indicates that the amount of protein decreased after exposure to both types of magnetic fields.Projekat ministarstva br. 17302
The analysis of 2,3-dicarboxypropane-1,1-diphosphonic acid-coated magnetite nanoparticles under an external magnetic field and their radiolabeling for possible theranostic applications
The advances in nanotechnology are directed towards the development of new theranostic agents based on magnetic nanoparticles that can be used for both cancer detection and treatment. In this study, 2,3-dicarboxypropane-1,1-diphosphonic acid-coated magnetite nanoparticles (Fe 3 O 4 -DPD MNPs) were evaluated for their theranostic application using different methods. The magnetic hyperthermia efficiency of the Fe 3 O 4 -DPD MNPs was investigated in saline solution with ionic strengths between 0.05 and 1.0 mol dm −3 . For a better understanding of hyperthermia, the behavior of Fe 3 O 4 -DPD MNPs under a non-alternating magnetic field was studied, and the transparency of the sample was measured. Furthermore, the radiotracer method using the radionuclides 99m Tc and 90 Y was applied as a reliable and powerful method for evaluating the in vivo behavior of a nanoprobe; a high radiolabeling yield (>93%), in vitro and in vivo stability of the radiolabeled nanoparticles and high heating effect were observed, thus paving the way for the possible theranostic applications of Fe 3 O 4 -DPD MNPs.This is the peer-reviewed version of the following article:Perić, M.; Radović, M.; Mirković, M. D.; Nikolić, A. S.; Iskrenović, P.; Janković, D.; Vranješ-Đurić, S. The Analysis of 2,3-Dicarboxypropane-1,1-Diphosphonic Acid-Coated Magnetite Nanoparticles under an External Magnetic Field and Their Radiolabeling for Possible Theranostic Applications. New Journal of Chemistry 2019, 43 (15), 5932–5939. [https://doi.org/10.1039/c8nj06478d]
Biogenic amines in protocerebral A2 neurosecretory neurons of Lymantria dispar L. (Lepidoptera:Lymantriidae): Response to trophic stress
The number, morphometric parameters and amount of aminergic neurosecretory product of protocerebral A2 neurosecretory neurons were investigated in the fifth instar of Lymantria dispar caterpillars, following a suitable or unsuitable trophic regime. Caterpillars originated from two populations (Quercus rubra or Robinia pseudoacacia forest) and were differently adapted to trophic stress, i.e. feeding on locust tree leaves - unsuitable host plant. The number of neurosecretory neurons was higher in the caterpillars originated from Robinia population than in Quercus population, regardless of feeding. A2 neurosecretory neurons, nuclei and their nucleoli were larger in caterpillars fed with unsuitable leaves in both populations. There was more aminergic product in the A2 neurosecretory neurons of the caterpillars fed with unsuitable leaves independently of population origin.Projekat ministarstva br. 17302