Correlation between Fructan Exohydrolase Activity and the Quality of Helianthus tuberosus L. Tubers

Jerusalem artichoke tubers have diverse applications in the food industry as well as in biotechnology. Their suitability depends mostly on the inulin content. Seasonal fluctuations of fructan exohydrolase activity responsible for inulin degradation was investigated in the tubers of three Jerusalem artichoke cultivars. The changes of fructan exohydrolase activity positively correlated with the changes of the content of total and short fructooligosaccharides. Therefore, to extract inulin with higher degree of polymerization for biotechnological purposes, the tubers of Jerusalem artichoke should be uprooted in autumn before the level of fructan exohydrolase reaches its maximum. If short fructooligosaccharides are desirable, the tubers in late autumn or spring tubers overwintered in soil are suitable

New β-Carotene-Chitooligosaccharides Complexes for Food Fortification: Stability Study

The application of β-carotene in food industry is limited due to its chemical instability. The drawback may be overcome by designing new delivery systems. The stability of β-carotene complexed with chitooligosaccharides by kneading, freeze-drying and sonication methods was investigated under various conditions. The first-order kinetics parameters of the reaction of β-carotene degradation were calculated. The complexation improved the stability of β-carotene at high temperatures and ensured its long-term stability in the dark at 4 °C and 24 °C, and in the light at 24 °C. In water solutions, the best characteristics were exhibited by the complexes prepared by freeze-drying and sonication methods. In the powder form, the complexes retained their colour for the period of the investigation of four months. The calculated total colour differences of the complexes were qualified as appreciable, detectable by ordinary people, but not large. Therefore, β-carotene-chitooligosaccharides complexes could be used as a new delivery system suitable for food fortification.This article belongs to the Special Issue Natural Carotenoids as Functional Food IngredientsThis research was funded by the European Social Fund under the No 09.3.3-LMT-K-712 “Development of Competences of Scientists, other Researchers and Students through Practical Research Activities” measure. Grant No 09.3.3-LMT-K-712-02-0039

Inactivation of Escherichia coli Using Nanosecond Electric Fields and Nisin Nanoparticles: A Kinetics Study

Nisin is a recognized bacteriocin widely used in food processing, however, being ineffective against gram-negative bacteria and in complex food systems. As a result, the research of methods that have cell wall–permeabilizing activity is required. In this study, electroporation to trigger sensitization of gram-negative bacteria to nisin-loaded pectin nanoparticles was used. As a model microorganism, bioluminescent strain of E. coli was introduced. Inactivation kinetics using nanosecond pulsed electric fields (PEFs) and nisin nanoparticles have been studied in a broad range (100–900 ns, 10–30 kV/cm) of pulse parameters. As a reference, the microsecond range protocols (100 μs × 8) have been applied. It was determined that the 20–30 kV/cm electric field with pulse duration ranging from 500 to 900 ns was sufficient to cause significant permeabilization of E. coli to trigger a synergistic response with the nisin treatment. The kinetics of the inactivation was studied with a time resolution of 2.5 min, which provided experimental evidence that the efficacy of nisin-based treatment can be effectively controlled in time using PEF. The results and the proposed methodology for rapid detection of bacteria inactivation rate based on bioluminescence may be useful in the development and optimization of protocols for PEF-based treatments

Continuation of the East Asian painting tradition in Dalia Dokšaitė's art

Straipsnis skirtas unikalaus mūsų ir plačiau žvelgiant Baltijos kraštų mene orientalistinio reiškinio Dalios Dokšaitės peizažinės tapybos analizei. Dailininkė savo kūrybinėmis bei pedagoginėmis nuostatomis įprasmina Rytų ir Vakarų estetikos bei dailės tradicijų sąveika. Autorė pagrindinį dėmesį sutelkia į Dokšaitės monochrominės ir polichrominės tapybos stiliaus ištakų ir savitumo atskleidimą, išryškina sąsajas su didingomis kinų ir japonų peizažinės tapybos tradicijomis, analizuoja tas Rytų Azijos estetines idėjas, kurios turėjo didžiausią poveikį savitai dailininkės peizažinės tapybos koncepcijai. Juk būtent Rytų Azijos peizažinė tapyba, kurios tradicijų tęsėja ir puoselėtoja tapo Dokšaitė, yra vienas rafinuočiausių pasaulinės dailės paveldo reiškinių, subtilių meninių vaizdinių kalba įkūnijančių gamtos ir būties pirmapradę harmoniją. Kaip parodoma straipsnyje, Dokšaitė ne tik tęsia Rytų Azijos peizažinės tapybos tradicijas, tačiau ir kūrybingai jungia jas su Lietuvos tautinės tapybos mokyklos tradicijomis.Article analyzes Dalia Dokšaitė's landscape painting that is a unique phenomenon of oriental art in both Lithuania and the Baltic countries. The artist's creative and pedagogical outlook gives the spectator a sense of interaction between Eastern and Western aesthetics and art traditions. The author of the article focuses on the disclosure of Dokšaitės monochrome and polychrome painting style and identity by highlighting linkages with the magnificent Chinese and Japanese landscape painting tradition, by analyzing East Asian aesthetic ideas that made great impact on the artist's original concept of landscape painting. Dokšaitė has become a successor to and a promoter of the traditions of East Asian landscape painting that belong the most sophisticated art heritages of the world expressed in a subtle visual language of art, embodied in the existence of natural and primordial harmony. However, as shown in the article, Dokšaitė not only continues in the vein of the magnificent traditions of East Asian landscape painting, but also combines them creatively with the Lithuanian national painting school

Kinetic Study of Encapsulated β-Carotene Degradation in Dried Systems: A Review

β-Carotene serves as a precursor of vitamin A and provides relevant health benefits. To overcome the low bioavailability of β-carotene from natural sources, technologies have been designed for its encapsulation in micro- and nano-structures followed by freeze-drying, spray-drying, supercritical fluid-enhanced dispersion and electrospraying. A technological challenge is also to increase β-carotene stability, since due to its multiple conjugated double bonds, it is particularly prone to oxidation. This review analyzes the stability of β-carotene encapsulated in different dried micro- and nano-structures by comparing rate constants and activation energies of degradation. The complex effect of water activity and glass transition temperature on degradation kinetics is also addressed, since the oxidation process is remarkably dependent on the glassy or collapsed state of the matrix. The approaches to improve β-carotene stability, such as the development of inclusion complexes, the improvement of the performance of the interface between air and oil phase in which β-carotene was dissolved by application of biopolymer combinations or functionalization of natural biopolymers, the addition of hydrophilic small molecular weight molecules that reduce air entrapped in the powder and the co-encapsulation of antioxidants of various polarities are discussed and compared, in order to provide a rational basis for further development of the encapsulation technologies

Kinetic Study of Encapsulated β-Carotene Degradation in Aqueous Environments: A Review

The provitamin A activity of β-carotene is of primary interest to address one of the world’s major malnutrition concerns. β carotene is a fat-soluble compound and its bioavailability from natural sources is very poor. Hence, studies have been focused on the development of specific core/shell micro- or nano-structures that encapsulate β-carotene in order to allow its dispersion in liquid systems and improve its bioavailability. One key objective when developing these structures is also to accomplish β-carotene stability. The aim of this review is to collect kinetic data (rate constants, activation energy) on the degradation of encapsulated β-carotene in order to derive knowledge on the possibility for these systems to be scaled-up to the industrial production of functional foods. Results showed that most of the nano- and micro-structures designed for β-carotene encapsulation and dispersion in the water phase provide better protection with respect to a natural matrix, such as carrot juice, increasing the β-carotene half-life from about 30 d to more than 100 d at room temperature. One promising approach to increase β-carotene stability was found to be the use of wall material, surfactants, or co-encapsulated compounds with antioxidant activity. Moreover, a successful approach was the design of structures, where the core is partially or fully solidified; alternatively, either the core or the interface or the outer phase are gelled. The data collected could serve as a basis for the rational design of structures for β-carotene encapsulation, where new ingredients, especially the extraordinary natural array of hydrocolloids, are applied

Screening of some vegetables for the biotransformation of bicyclo[3.3.1]nonane-2,6-diol diacetate

Vegetables as biocatalysts were screened for the stereoselective biotransformation of racemic bicyclo[3.3.1]nonane-2,6-diol diacetate. The best results were obtained using the roots of carrot (Daucus carota) and parsnip (Pastinaca sativa) and the rootstocks of ginger (Zingiber officinale). During the biotransformation of racemic bicyclo[3.3.1]nonane-2,6-diol diacetate the enzymatic hydrolysis took place. Under different reaction conditions, i.e. the reaction temperature and time, and using different plant material as biocatalyst, (1R,2R,5R,6R)-(+)-bicyclo[3.3.1]nonane-2,6-diol monoacetate or (1S,2S,5S,6S)-(-)-bicyclo[3.3.1]nonane-2,6-diol monoacetate were obtained as reaction products. (–)- Enantiomer with the optical purity of 29.3% was obtained at 25°C using parsnip as biocatalyst for 2 days and (+)- enantiomer with the optical purity of 44.1% was obtained at 30°C using carrot for 3 days

Preparation of nisin-loaded pectinchitooligosaccharides particles

Nowadays, food preservation plays a tremendous role in food industry. However, the majority of food preservatives are synthetic chemicals and most of them have a harmful effect on human health. Nisin is the one of the commonly used natural additives for dairy and canned food products. This bacteriocin is generally recognized as safe (GRAS) and has a number E234. Nisin is a small 3510 Da cationic peptide composed of 34 amino acid residues. Nisin is produced by Lactococcus lactis subsp. lactis and has the broad-spectrum antimicrobial activity against Gram – positive bacteria [1]. The action is based on the formation of pore in the bacterial cell wal

Iron oxide magnetic nanoparticles functionalized by nisin

Over the last decades iron oxide magnetic nanoparticles, mostly magnetite (Fe3O4) and maghemite (γ–Fe2O3), have increasingly attracted attention as an efficient tool in various fields of application [1]. Here, we present the preparation and characterization of iron oxide magnetic nanoparticles functionalized by nisin. Nisin is naturally produced by Lactococcus lactis subsp. lactis as a small cationic peptide composed of 34 amino acid residues and is a well-known bacteriocin approved as a food additive for food preservation [2]. Iron oxide magnetic nanoparticles were prepared by the co-precipitation method and characterized by X-ray diffraction method. Magnetic nanoparticles were stabilized by citric, ascorbic, gallic, or glucuronic acid coating and were functionalized by nisin using a simple and low-cost adsorption method (Fig. 1). Nisin loading was confirmed by FT-IR spectra, thermogravimetric analysis, and dynamic light scattering methods. Nisin-loaded iron oxide magnetic nanoparticles were stable for at least six weeks as judged by zeta-potential and hydrodynamic diameter measurements. The functionality of nisin-loaded iron oxide magnetic nanoparticles was demonstrated on Grampositive bacteria. Functionalized nanoparticles could find their application in innovative and emerging technologies as antimicrobials