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INFLUENCE OF EXTRACTION CONDITIONS ON CONTENT OF BIOLOGICALLY ACTIVE SUBSTANCES FROM POMACE OF CABERNET SAUVIGNON AND RARA NEAGRA GRAPES
Get PDFGrape pomace contains many anthocyanins, catechins, flavonoids, phenolic acids, and stilbenes, so it must be utilized. The research used grape pomace from Cabernet Sauvignon and Rara Neagra, harvested in 2023. When creating the absorption spectra, a high content of anthocyanins was observed – components that describe the most significant increases in the spectral line at wavelengths between 510 and 550 nm, specific to these phenolic compounds, confirming the participation of anthocyanins in the formation of the color of grapes as main constituents. Studying the anthocyanin content showed that most pigments that gave the red color were found in acidulated samples of Cabernet Sauvignon, with an extraction temperature of 40°C. The same trend was observed in the acidulated extract of Rara Neagra with extraction temperatures of 40°C and 55°C. When determining the total phenolic content, values ranged between 4.59-5.16 mg GAE/g DW for Cabernet Sauvignon and 4.62-5.98 mg GAE/g DW for Rara Neagra. The antioxidant activity varied in Cabernet Sauvignon between 72.06-86.4%, and in Rara Neagra between 76.79-88.64%. The lowest values were recorded in the non-acidulated samples: 72% for Cabernet Sauvignon and 76.8% for Rara Neagra. As a result, acidulated extracts were the richest in biologically active substances
REFLECTIONS CONCERNING INTERNSHIPS FOR THE CAR ELECTRICIAN-ELECTRONICS QUALIFICATION
Get PDFWork-based learning is an essential area for both the private and public sectors, contributing to the development of the economic and social sector. In this regard, various studies and analyses are conducted to highlight the best workplace training practices. In this article, the authors aim to present the results obtained through a survey of students during their internship for the auto electrician-electronics trade. The research methods used were quantitative (242 respondents) and qualitative (43 questions) and aimed at the way of carrying out the internships for the car electrician-electronics qualification, the results obtained during the research being highlighted. The authors believe that the results presented in this article are relevant not only to the secondary technical vocational training field but also beyond
PHYSICAL SELF-ESTEEM OF ALBINOS IN KINSHASA AND ITS EXPLANATORY FACTORS
Get PDFThe aim of this research was to assess the physical self-esteem of albinos in the Democratic Republic of Congo (more specifically, those living in the city-province of Kinshasa), and to identify the most explanatory factors. With this in mind, a physical self-esteem inventory was applied to 70 albinos living in Kinshasa, members of the Mwimba Texas Association. Following the administration of this inventory, it was found that the albinos surveyed had positive physical self-esteem. This positive self-esteem manifested itself in a positive perception of: (1) overall self, (2) physical value, (3) physical appearance and (4) strength. The study of explanatory determinants made it possible to target two factors that influenced all the dimensions of the self-esteem of the subjects surveyed (support of entourage and perception of albinos by entourage)
VISUAL ARTS EDUCATION FOR DESIGN STUDENTS FROM THE PERSPECTIVE OF MUSEUM EDUCATION IN A SOCIAL CONTEXT
Get PDFThe article is a theoretical-practical study, focused on valorization of the visual arts education for design students in the context of museum education. The paper reveals fundamental concepts, identifies certain perspectives to researches in the targeted field. Additionally, it specifies and describes several essential educational aspects, such as the objectives of visual arts education; the value axes centered on visual arts education; cognitive processes developed by design students during activities carried out in museums; educational actions regarding the optimization of visual arts education for design students; strategies and methods (scientific documentation, analysis and synthesis, conversation, product study, etc.) of enhancing visual arts education for design students. The study specifies, analyzes, and validates the positive impact of activities conducted in museum spaces on the visual arts education of design students, focused on achieving these aspects in the context of university-museum collaboration. In conclusion, an approach to visual arts education of design students from the perspective of national and universal artistic heritage can ensure both the optimization of initial training for design students and lifelong education
IMPLEMENTAREA METODEI PCR PENTRU IDENTIFICAREA TULPINILOR PATOGENE ALLORHIZOBIUM VITIS CE PROVOACĂ CANCERUL BACTERIAN AL VIȚEI-DE-VIE
Get PDFIn the process of obtaining grapevine clones free from viral diseases and bacterial cancer, there are often cases where protoclones, seemingly healthy, well-developed, and with high yields, are found to be latently infected with bacterial cancer. This disease is most caused by agrobacteria from the genus Allorhizobium vitis and sometimes by Agrobacterium tumefaciens, and it is one of the most destructive diseases for grapevines from an economic perspective. The bacterial pathogen exists systemically in grapevines and spreads through infected propagation material. In the present study the Triplex End-Point PCR method was used for accurate and rapid identification of pathogenic strains of agrobacteria. One-year-old mature vines from 6 varieties and forms of grapevines were taken for the research. Microbiological testing on Roy & Sasser semiselective medium showed that five of the six plants tested were positive for Agrobacterium spp. infection. The positive tested samples were subjected to PCR testing. The presence of PehA gene, which is used to identify Allorhizobium vitis and to differentiate it from Agrobacterium tumefaciens, was confirmed in all tested samples. The virF and virD regions associated with the production of nopalins, octopins and vitopns were also detected. The test results suggested that the method allows for the reliable detection of pathogenic cultures carrying the tumor-inducing plasmid. The obtained results contribute to the development of strategies to combat bacterial cancer infections and improve phytosanitary selection practices for grapevine propagation material.
În procesul de obținere a clonelor de viță de vie libere de boli virale și de cancer bacterian, adesea se observă cazuri în care plantele, aparent sănătoase, bine dezvoltate și cu o producție ridicată, se dovedesc a fi infectate latent cu cancer bacterian. Această boală este cauzată cel mai des de agrobacterii din genul Allorhizobium vitis și uneori de Agrobacterium tumefaciens și este una dintre cele mai distructive boli, din perspectivă economică, pentru vița de vie. Patogenul bacterian există sistemic în vița de vie și se răspândește prin materialul de propagare infectat. În prezentul studiu a fost utilizată metoda PCR Triplex End-Point pentru identificarea precisă și rapidă a tulpinilor patogene de agrobacterii. Pentru realizarea cercetărilor au fost prelevate vițe mature de un an de la 6 soiuri și forme de viță de vie. Testarea microbiologică pe mediul semiselectiv Roy & Sasser a demonstrat că cinci dintre cele 6 plante testate au prezentat rezultate pozitive pentru infecția cu Agrobacterium spp. Loturile testate pozitiv au fost transferate la etapa investigației prin metoda PCR. În toate probele testate a fost confirmață prezența genei PehA (466 bp), care servește pentru identificarea bacteriei Allorhizobium vitis și pentru diferențierea ei de Agrobacterium tumefaciens. De asemenea s-au detectat regiunile virF (382 bp) și virD (320 bp) asociate cu producția de nopaline, octopine și vitopine, ce servesc drept sursă de nutrienți pentru bacterii. Rezultatele testărilor au sugerat că metoda permite detectarea fiabilă a culturilor patogene purtătoare de plasmida inductoare de tumori. Rezultatele obținute contribuie la dezvoltarea strategiilor de combatere a infecțiilor cu cancer bacterian și la îmbunătățirea practicilor de selecție fitosanitară a materialului de multiplicare viticol
METHODOLOGY APPLIED IN THE CONSTRUCTION OF STRUCTURES USING NATURAL AND ALTERNATIVE MATERIALS FOR STABILIZATION WORKS IN ROAD CONSTRUCTION
Get PDFThe analysis of the current state of applications and the results of studies carried out at international level have led to the approach of an eco-efficient methodology for the recovery of waste generated from construction activities, demolition, and the addition of alternative stabilising materials to obtain optimized structures capable of providing a higher quality of the works carried out. Three types of stabilising slurry agents were selected for the experimental programme: the water-based polymer product AggreBind (AGB-BT), the Terra 3000 solution based on the Power binder, and the Earthzyme polysemantic product. Experimental studies on the use of these types of products in earthworks for stabilizing embankments, building and repairing road systems and industrial platforms have shown significant increases in strength and bearing capacity. The use of these environmentally beneficial alternative materials has led to significant reductions in construction time, decreasing total construction and maintenance costs in the short and long term
EXPLORING THE MICRO AND MACRO TERROIR OF FETEASCĂ NEAGRĂ WINE FROM MOLDOVA
Get PDFThis study delves into the intricate realm of Moldovan winemaking, focusing on the iconic Fetească Neagră grape variety. The research highlights the importance of indigenous grape varieties in shaping a unique wine identity for the region. Drawing on the concept of terroir, the study investigates the microbial terroir specific to three designated geographical regions in Moldova during the 2022 vintage. The research employs a multifaceted approach, combining climate data analysis, mini vinification experiments, microbial DNA extraction, and sensory evaluation techniques. Results reveal significant variations in climatic conditions and microbial diversity across the three regions, influencing the sensory characteristics of the resulting wines. On vintage 2022 the Codru is temperature， and the Stefan-Voda and Vadul lui Traian are warm climates. All the 3 regions are moderately dry. The Stefan Voda is 14.0%， and manifests the highest ethanol content among the regions, alongside the lowest pH level. The sensory evaluations show Stefan Voda evincing heightened creaminess, Codru showcasing prominent herbal nuances, and Vadul lui Traian displaying elevated scores in berry, cherry, violet, and black pepper descriptors. Through meticulous analysis, the study underscores the dynamic interplay between environmental factors, microbial communities, and wine attributes, shedding light on the complex tapestry of Moldovan winemaking. Ultimately, this research contributes to a deeper understanding of terroir-driven wine production and emphasizes the importance of preserving indigenous grape varieties to uphold the distinctiveness of Moldovan wines on the global stage
HARNESSING GRAPE POMACE: NUTRITIONAL ASPECTS, RECOVERY AND EXTRACTION TECHNIQUES FOR HEALTH BENEFITS
Get PDFNowadays, grapes represent the third most widely cultivated horticulture crop in the world. For the Republic of Moldova, grapes have been recognized as the most culturally important crop. About 70% of the total production of Moldovan grapes is processed in the wine industry, 30 % of which are by-products that tend to be not fully exploited, being frequently burned or landfilled. Due to its chemical composition, grape pomace is one type of agricultural waste that can be used to achieve sustainability in the food business by converting waste into useful resources. In this sense, the pomace chemical composition, with demonstrated antioxidant potential, is a viable source of biologically active compounds, as a cheap agricultural waste product, for the development of functional products. This paper is an overview of the characteristics and potential uses of wine industry waste, namely grape pomace and explores the implementation of eco-friendly technologies that have the potential to convert this perishable material into a unique ingredient, unveiling fresh opportunities for the grape pomace's utilization and consumption
Eu3+ AS A LUMINESCENT PROBE FOR LOCAL SITE SYMMETRY IN Eu(III) COORDINATION COMPOUNDS
Get PDFThe paper deals with the use of tripositive ion Eu3+ as a luminescent probe for the evaluation of the local site symmetry in coordination compounds with europium(III) content. The energy levels of the Eu3+ multiplets in the ligand matrix may be split by the crystal field into a maximum number of 2J+1 components, depending on the site symmetry of the Eu3+ ion. Analysis of photoluminescence spectra provides information on the local site symmetry of the compound. The topic is discussed with reference to literature data as well as own experimental results obtained in the Laboratory of Optoelectronics "A. Andries" of the Institute of Applied Physics. This work gives a deeper insight into the spectral characteristics of Eu3+ ions in ligand matrices and can be a guiding support for investigation of photoluminescence in Eu(III) complexes
OIL CROP POMACE AS A POTENTIAL SOURCE OF PROTEIN AND DIETARY FIBER
Get PDFThe oil industry market is promising worldwide, including in the Republic of Moldova. The growth of vegetable oil production has led to the formation of a large amount of waste – oil crop pomace (meal), which is usually discarded or used in small quantities as animal feed and becomes a serious environmental problem. The aim of this work is to analyze and study different kinds of oil crop pomace, which can be used as a functional ingredient in product development due to its beneficial components, dietary fiber, and protein. This review presents the classification of meals, the methods of their production, chemical composition, protein, and dietary fiber extraction methods, also their characteristics are discussed. Harmless extraction methods are preferred as they reduce the number of reagents used, reduce waste, and increase the yield. The review presents physicochemical parameters of protein concentrates, isolates, and dietary fibers, which are actively used for valuable food additives production, used as low-calorie ingredients or texture stabilizers in the formulations of various food products