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Thesis (Ph. D.)--Swedish University of Agricultural Sciences, 2001. / Includes bibliographical references.

Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Food Science." Includes bibliographical references (p. 53-56).

Šio darbo tikslas yra tirti Lietuvos serbentinių amarų biologiją, įvairovę ir sistematiką. Lietuvoje registruota 14 serbentinių amarų rūšių (Rakauskas, Rupais, Juronis, 1992). Amarai tyrimams buvo rinkti 2003-2005 metais Vilniaus ir Kretingos rajonuose bei Kuršių nerijoje. Be to, panaudota medžiaga, saugoma Vilniaus Universiteto Zoologijos katedros kolekcijoje. 2003-2005 metais Lietuvoje buvo rasta 10 serbentinių amarų rūšių, registruotos naujos Cryptomyzus alboapicalis radimvietės mūsų šalyje, ir rastos tris Lietuvai naujos amarų rūšys: Aphis lamiorum, Cryptomyzus ulmeri ir Hyperomyzus lampsanae. Vilniaus Universiteto Zoologijos katedros kolekcijoje rasta 13 serbentinių amarų rūšių. Patikrinus kolekcinę medžiagą, pirmą kartą Lietuvoje rasti Eriosoma grossulariae rūšies amarai. Nustatytos naujos Cryptomyzus korschelti, Hyperomyzus pallidus ir Nasonovia ribisnigri radimvietės. Pirmą kartą Lietuvoje registruotas Cryptomyzus stachydis nuo Stachys silvatica ir Galeopsis sp.. Cryptomyzus galeopsidis ir Cryptomyzus maudamanti yra morfologiškai labai panašios rūšys, kartais jas sunku teisingai apibūdinti. Per tyrimų laikotarpį Cryptomyzus maudamanti rūšies amarų Lietuvoje nerasta. Kanoninės diskriminantinės funkcijos, pateiktos apibūdinimo raktuose (Guldemond 1991a; Heie 1994), negali patikimai atskirti C. galeopsidis ir C. maudamanti (17 ir 18 lentelės). Naudojant Čekijos Mokslų Akademijos Entomologijos Instituto kolekcinę medžiagą buvo atlikta diskriminantinė analizė ir gauta... [toliau žr. visą tekstą] / The aim of this study was to learn about the biology and diversity of currant aphids in Lithuania. 14 currant aphid species have been recorded in Lithuania (Rakauskas, Rupais, Juronis, 1992). For this study aphids were collected in Vilnius and Kretinga districts and on Curonian spit in 2003-2005. Currant aphid collection stored at the Department of Zoology, Vilnius University, was also analyzed. In 2003-2005 10 species of currant aphids were found in Lithuania, new collection sites of Cryptomyzus alboapicalis were detected and three new to Lithuania aphid species: Aphis lamiorum, Hyperomyzus lampsanae and Cryptomyzus ulmeri were found. 13 currant aphid species are stored at the collection of Department of Zoology, Vilnius University. Eriosoma grossularia was found after checking the collection material with a new Daniellson’s identification key to genus Eriosoma. More collection sites of Hyperomyzus pallidus, Cryptomyzus korschelti and Nasonovia ribisnigri were detected. Cryptomyzus stachydis from Stachys silvatica and Galeopsis sp. was registered in Lithuania for the first time. Cryptomyzus maudamanti and Cryptomyzus galeopsidis are two morphologically very similar species, and in some cases it is difficult to identify them correctly. Cryptomyzus maudamanti was not found in Lithuania during this study period. Canonical discriminant function offered in the identification keys (Guldemond 1991a; Heie 1994) proved to be not reliable to discriminate between C. galeopsidis and C... [to full text]

Darbo tikslas: ištirti juodųjų serbentų (Ribes nigrum L.) produktų, pasižyminčių antioksidantinėmis savybėmis įtaką triušių virškinimo procesams ir produktyvumui. Darbo tikslas įgyvendintas sprendžiant šiuos uždavinius: 1) aukštos apykaitynės energijos gautos iš padidinto riebalų kiekio racionų sudarymas, žolės miltus pakeičiant juodųjų serbentų išspaudomis; 2) nustatyti triušių kūno svorio, priesvorio, pašarų sąnaudų su juodaisiais serbentais sąveiką; 3) ištirti juodųjų serbentų išspaudų įtaką atskirų virškinimo trakto segmentų turinio pH ir sausųjų medžiagų kiekiui;4) nustatyti juodųjų serbentų išspaudų įtaką klubinės žarnos turinio klampumui, aklosios žarnos turinio amoniako kiekiui; 5) ištirti trumpųjų grandinių riebalų rūgščių (TGRR) koncentraciją ir sudėtį aklojoje žarnoje; 6) nustatyti juodųjų serbentų išspaudų įtaką aklosios ir gaubtinės žarnų turinio baltymų, bakterijų fermentiniams (α- ir β-galaktozidaziniams, gliukozidaziniams, α- ir β-gliukozidaziniams ir β-gliukuronidazidaziniams) aktyvumams ir lakiųjų riebalų rūgščių (LRR) kiekiams; 7) nustatyt ipoveikį triušių antioksidantinio aktyvumo rodikliams; 8) nustatyti poveikį biocheminiams kraujo rodikliams; 9) ištirti triušių aterogeniškumo ir atsparumo insulinui rodiklius. Išvados: 1) Juodųjų serbentų išspaudų naudojimas pakeičiant žolės miltus, patvirtino hipotezę, kad jos gali būti laikomos veiksminga ir prieinama pašarų sudedamąją dalimi triušių racionuose. 2) Raciono papildymas juodųjų serbentų išspaudomis... [toliau žr. visą tekstą] / Researches were conducted in the Animal Husbandry Department of the Veterinary Academy of Lithuanian Health Sciences University, also in the vivarium of Lithuanian Veterinary Academy and in the Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences. New Zealand rabbits were used for the researches. All rabbits were calved over one cycle of reproduction (50 percent were male and 50 percent were female). All rabbits were assigned to four groups of five individuals each. The rabbits of the control group (K) were fed a standard diet; the group KP was fed a standard diet with increased fat volume. The rabbits of the group E were subjected to a standard diet with the addition of blackcurrant polyphenolic extract (1,5 percent), the animals of the group EP were fed a standard diet with increased fat volume + blackcurrant extract (1,5 percent). Duration of the research was 45 days. Rabbits were stored in the individual flat-bottomed wire cages in closed room. Over the research all rabbits were fed and watered ad libitum. The research included observation of rabbit growth dynamics, level of ammonia in the substance of cecum, activity of microbe ferments, short-chain fatty acids, and research of overall wellness. Thegoalofthepaper: to investigate the effect of blackcurrant (Ribes nigrum L.) products distinguishing for antioxidant features on digestive processes and productivity of rabbits. The goal of the paper has been achieved by solving the following... [to full text]

Growing numbers of morbidity and mortality due to the cancer and coronary heart disease is recognized as the increasing challenge in the world. The initial stage of these diseases, early diagnosis and treatment are the main objectives of current researches. According to Lithuanian Health Information Centre morbidity and mortality due to these diseases in Lithuania exceed average of European Union. The oxidative stress occurs in cells as a result of normal physiological processes and environmental interactions, and the complex antioxidant defense system are of particular importance in protecting biological systems against oxidative damage by free radicals. Recently polyphenols and anthocyanins containing foods and preparations have attracted attention due to their health promoting benefits. Anthocyanins make one of the main groups of flavonoids, and represent polyphenolic compounds, that are found in vegetables and fruits, particularly in berries. An important effect of anthocyanins is the scavenging of oxygen-derived free radicals. They can interfere with few different free radical-producing systems, and can increase the function of the endogenous antioxidants. The aim of the research is to choose sources for the products with antioxidant activity from plants cultivated in Lithuania, evaluate quality and antioxidant activity of black currant, red currant and chokeberry products, to develop and evaluate technologies of phytopharmaceuticals with antioxidant activity... [to full text]

This diploma thesis deals with the elemental analysis of soft fruit species such as currants and gooseberries. The theoretical part contains botanical description of both species, then description of nutritional properties of the individual analyzed elements and ends with a list of analytical methods suitable for elemental analysis in the food science and with a description of preparation. The experimental part deals with sample preparation and its analysis afterwards with spectroscopic techniques. Samples of different varieties of gooseberries, black, red and white currant from “Výzkumný a šlechtitelský ústav ovocnářský v Holovousích, s.r.o.” have been used for the analysis. Samples were mineralized in concentrated HNO3 and analyzed by ICP-OES technique. Difference in resultant concentrations of the analyzed elements (Ca, Cu, Fe, K, Mg, Mn, Na, P, Zn) between individual varieties were statistically compared by Tukey’s multiple comparison method and results achieved have been as well compared with the results reported in available literature.

This master thesis deals with the assessment of aroma active compounds in fruits of currant (Ribes spp.). The theoretical part was focused on basic characteristics and chemical composition of currants, as well as the basic principles of techniques used: solid phase micro extraction (SPME), gas chromatography (GC) and sensory analysis. The main aim of the experimental part was to determine aroma active compounds in currants using SPME-GC-FID method. The profile and scale tests were used for assessment of sensory quality and tastiness of fruits. In total 18 varieties, among them 6 white, 6 red and 6 black currants, were evaluated. Fifty aroma active compounds were identified including 21 alcohols, 10 aldehydes, 2 acids, 8 ketones and 9 esters. The results were statistically evaluated using principal component analysis (PCA) to investigate the influence of single compounds on sensory quality of fruits.

The work deals with the chemical analysis of juices selected varieties of black currant (Ribes nigrum L.). The theoretical part is divided into three main chapters. In the first chapter there are short botanical characteristics of black currants, content of biologically active substances in fruit and utilization of black currant fruit in food industry. In the second chapter there are characteristics, importance and methods of determination of phenolic compounds. Vitamin C is describe in the last chapter, its characteristics, importance and methods of determination. Experimental part describes determination of three chemical characteristic of black currant fruits: content of total phenolic compounds, content of total anthocyanins and content of vitamin C. Twelve modern varieties of black currant were selected for determination. Based on these results, it is possible to deduce the more important varieties. The content of total phenolic compounds was in the range of 326,7–641,4 mg•100 g-1 in all samples. The content of total anthocyanins was analysed in the range from 102,5 to 284,5 mg•100 g-1 in all samples. And content of vitamin C was in the range from 82,0 to 379,1 mg•100 g-1 in all samples. The overall comparison of the varieties of black currant was found, the varieties Ceres, Ben Hope, Ben Lomond, Démon and Ometa are the most promising varieties in terms of the content of the above mentioned compounds.

Diploma thesis deals with currant (Ribes L.) and substances which currants contain especially anthocyanin pigments, vitamin C and antioxidants. In theoretical part is described basic characteristic about plant, including varieties of currants. The following chapters include a list of active substances which the fruit contains and also the list of some possibilities of processing and utilization of currant especially in the food industry. Big attention is given to anthocyanins, their characteristics, utilization in the food industry, factors that affect their stability and especially methods of determination. In conclusion, the theoretical part describes importance and methods of determination of vitamin C and antioxidant capacity. Selected nutritional parameters were determined in fifteen known and in three unknown varieties of currants. Anthocyanins were measured spectrophotometrically and determined by HPLC in color samples. By pH differential method was evaluated a content of monomeric and polymeric pigments. By HPLC method were identified individual anthocyanin pigments contained in fruits. Also, content of ascorbic acid was determined by HPLC in all varieties. Antioxidant capacity of white currants measured by DPPH was compared.