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1
المؤلفون: Petra Pavelková, Ales Krmela, Věra Schulzová
المصدر: Acta Chimica Slovaca. 13:6-12
مصطلحات موضوعية: chemistry.chemical_classification, 0404 agricultural biotechnology, Chromatography, chemistry, 010401 analytical chemistry, 04 agricultural and veterinary sciences, General Medicine, 040401 food science, 01 natural sciences, Carotenoid, Hplc dad, 0104 chemical sciences
الوصف: Marigold flowers (Tagetes patula and Calendula officinalis) were chosen for analysis because they are the most often used source of lutein and its isomer zeaxanthin for the production of food supplements on the Czech market. Direct extraction and extraction with alkaline hydrolysis were compared to detect free or bound carotenoids. For carotenoid separation, C18 and C30 columns were used. A new method for determination of carotenoid content in food supplements in form of capsules has been developed and validated. All matrices were analysed by high-performance liquid chromatography with diode array detection (HPLC-DAD). It has been found that alkaline hydrolysis is required for both Marigold flowers and food supplements to release lutein from ester bonds to fatty acids. In Calendula officinalis lutein in the concentration of 807—1472 mg·kg−1 of dry matter was detected. Tagetes patula has been identified as a better lutein source with the content of 5906—8677 mg·kg−1 of dry matter. It has been found that the content of lutein and zeaxanthin in commercial food supplements (Lutein Complex Premium and Occutein Brillant) is consistent with the declared quantity. Linearity of the HPLC-DAD method ranged from 0.1—20 μg·mL−1 with the limit of quantification (LOQ) of 1.7 mg·kg−1 for lutein in Marigold flowers and 200 mg·kg−1 in food supplements. Repeatability was 2.3 % for lutein in all tested matrices.
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2
المؤلفون: Ales Krmela, Jana Hajslova, Hana Chmelarova, Vera Schulzova, Martin Koudela, Cenek Novotny
المصدر: Cells
Volume 10
Issue 4
Cells, Vol 10, Iss 784, p 784 (2021)مصطلحات موضوعية: 0106 biological sciences, carrot cultivars, Antioxidant, farming conditions, medicine.medical_treatment, Ethyl acetate, Ecological and Environmental Phenomena, Coumaric acid, spontaneous infection, 01 natural sciences, Article, chemistry.chemical_compound, Metabolomics, metabolomic fingerprinting, medicine, carotenes, Food science, Cultivar, 6-methoxymellein, lcsh:QH301-705.5, Plant Diseases, Principal Component Analysis, 010401 analytical chemistry, Carotene, Agriculture, General Medicine, Ascorbic acid, Carotenoids, 0104 chemical sciences, Daucus carota, 6-Methoxymellein, chemistry, lcsh:Biology (General), Metabolome, ascorbic acid, 010606 plant biology & botany
الوصف: Carrot serves as a source of health-beneficial phytochemicals for human diet whose content is affected by agroecological conditions. The effect of conventional, integrated and organic farming on ascorbic acid (AA) and α,β-carotene levels of new carrot cultivars Cortina F1 and Afalon F1 was investigated and their metabolomic profiles were measured by direct analysis in real time ion source coupled with a high-resolution mass spectrometer (DART-HRMS). Cortina and Afalon exhibited high levels of AA and total carotenes under all agroecological conditions tested that fluctuated in broad ranges of 215–539 and 173–456 mg AA.kg–1 dry biomass and 1069–2165 and 1683–2165 mg carotene.kg–1 dry biomass, respectively. The ratio of β- to α-carotene in both cultivars was about 1.3. The most important variable for the PCA and the partial least squares discriminant analysis (PLS-DA) models for ethyl acetate extracts measured in positive and negative ionization mode was 6-methoxymellein (6-MM). Total carotene content and 6-MM levels were higher in the organic carrot compared to the conventional one and were correlated with a higher level of spontaneous infection. Other important compounds identified were sitosterol, hexose and various organic acids including antioxidant ferulic and coumaric acids. The findings allow comparison of metabolomic profiles and the AA and carotene contents of both cultivars with those of other commercially used carrots.
وصف الملف: application/pdf
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3
المؤلفون: D Revenco, R Koplik, Ales Krmela, Vera Schulzova, P Kastanek, Milena Stranska-Zachariasova, Jana Hajslova, T Fulin, Jana Kohoutkova, Monika Jiru
المصدر: J Food Sci Technol
مصطلحات موضوعية: 0106 biological sciences, chemistry.chemical_classification, 0303 health sciences, Lutein, 030309 nutrition & dietetics, Chlorella vulgaris, food and beverages, chemistry.chemical_element, 01 natural sciences, Bioavailability, 03 medical and health sciences, chemistry.chemical_compound, chemistry, Scenedesmus obliquus, 010608 biotechnology, Vischeria helvetica, Original Article, Food science, Carotenoid, Selenium, Food Science, Polyunsaturated fatty acid
الوصف: In line with the growing interest in humans’ nutrition, production of microalgae-based functional foods characterized by an increased content of bioactive substances is attractive. The aim of this study was to investigate the potential of microalgae as additives to feed for laying hens, to enrich the eggs with polyunsaturated fatty acids (PUFA) and selenium/carotenoid antioxidants. Our results showed that supplementation of hens by feed containing 1% of Trachydiscus minutus or 1% of Japonochytrium marinum leads to increase of long-chain PUFA in eggs by 26–66%. Addition of 1% of Scenedesmus obliquus to feed causes the increase of lutein and cantaxanthin in eggs by 48% and 18%, respectively, and addition of 0.5% selenium enriched Chlorella vulgaris increases the final content of organic selenium in eggs by 100–152%. As concerns selenium, it is important to notice that its bioavailability has to be considered. Despite the higher concentration of total selenium in Vischeria helvetica than in C. vulgaris, its bioaccessibility in Vischeria was limited, thus out of usage for feeding purposes. Administration of combinations of selenium enriched Chlorella + Japonochytrium and Chlorella + Schizochitrium verified the increased concentrations of organic selenium, PUFA, as well as carotenoids, with no adverse effect on quality and productivity of eggs. The study confirmed the potential of both traditional as well as new microalgae to be used as feed supplements for functional eggs production. The supplementation of hens by specific microalgae combinations could be advantageous in terms of spectrum of bioactive compounds present. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13197-020-04896-3) contains supplementary material, which is available to authorized users.
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5a6225fad9de3879b9c22d21b5248121
https://europepmc.org/articles/PMC8405822/ -
4
المؤلفون: Ales Krmela, Mariana Tesarova
المصدر: Trendy ekonomiky a managementu. 2020, XIV, č. 35, s. 59-72. ISSN 1802-8527.
مصطلحات موضوعية: Process management, business.industry, Process (engineering), Value proposition, 05 social sciences, Value capture, 010501 environmental sciences, Business model, sustainability, 01 natural sciences, business model adaptation, Product (business), Manufacturing, business model, 0502 economics and business, Sustainability, Business, environmental sustainability, Adaptation (computer science), 050203 business & management, 0105 earth and related environmental sciences
الوصف: Purpose of the article: The article aims at understanding and description of how and why the business model (BM) of an incumbent manufacturing B2B company adapts, collaboratively with a dominant customer, through measures leading to an improved environmental sustainability performance. The research question was: How is a business model of an incumbent, businessto-business company adapted through the inclusion of environmental sustainability measures, with the customer’s involvement? Methodology/Methods: A qualitative research approach, drawing on a descriptive-explanatory, single case study conducted on a Czech manufacturing company active in the field of steel processing was performed. The study draws on the analysis of the focal company’s internal and external documents related to sustainability, as well as on semi-structured interviews with the examined company’s executives. The analysis also include the externally available sustainability related documents of a dominant customer. Scientific Aim: Understanding the impact of the environment-related sustainability measures on the adaptation of the extant BM of the focal company, and the role a dominant customer plays in the process. Findings: The inclusion of environment-related sustainability measures leads to an adaptation of the process and the product, as well as of the focal company’s BM and most of its key elements. A value capture by the focal company has been identified as the mainly affected element of a BM through both cost savings and a more business gained. The element value proposition adapts towards a “greener company”. The core logic of the BM remains unchanged. Conclusions: B2B incumbent companies implement environmental sustainability measures into their BMs, aiming to contribute to the preservation of the environment. The economic side continues to be carefully considered. It can even be a trigger of implementation. The large customers get strongly involved in the process, contributing to the adaptation of all four key elements of the BM. The BM’s adaptation happens dynamically, in incremental steps.
وصف الملف: text; application/pdf
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cd2a10aa6686a36cc6f0dfa19101f51e
https://hdl.handle.net/11012/195029 -
5
المؤلفون: Iveta Šimberová, Peter Kita, Ales Krmela
المصدر: 10th International Scientific Conference “Business and Management 2018”.
مصطلحات موضوعية: Product innovation, 05 social sciences, Sustainable innovation, Scientific literature, 010501 environmental sciences, Space (commercial competition), Business model, 01 natural sciences, Competition (economics), Resource (project management), 0502 economics and business, Business, Limited resources, 050203 business & management, Industrial organization, 0105 earth and related environmental sciences
الوصف: The objective of the paper is to dynamically capture the changes and trends in the innovation of business models of industrial enterprises, which owing to the incorporation of any other potential stakeholders in value creation, addresses the issue of limited resources for product innovation. The methodological objectives of the paper are based on the theory of systems approach and the Resource Base View (RBV). A primary literary source review on papers and studies published in peer-reviewed journals has been conducted. Our view, which has received increasing attention in the scientific literature, is associated with opportunities, but also barriers arising from the changes and trends in the environment as a challenge for sustainable innovation of the business model by means of finding a new space for innovation in areas where competition is not active. The main output show, that business models should be viewed from a dynamic perspective. The basis for this is the prospect of developing or innovating of the business model as a result of internal and external changes over time. DOI: https://doi.org/10.3846/bm.2018.18
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_________::2a475c5639b76d38180eba2541709224
https://doi.org/10.3846/bm.2018.18 -
6
المؤلفون: Martin Koudela, Vera Schulzova, Katerina Svobodova, Cenek Novotny, Ales Krmela, Jana Hajslova
المصدر: Molecules, Vol 23, Iss 8, p 1855 (2018)
Molecules : A Journal of Synthetic Chemistry and Natural Product Chemistry
Molecules
Volume 23
Issue 8مصطلحات موضوعية: 0106 biological sciences, Antioxidant, medicine.medical_treatment, Pharmaceutical Science, Context (language use), Brassica, Environment, 01 natural sciences, Antioxidants, Article, Analytical Chemistry, Glucobrassicin, lcsh:QD241-441, chemistry.chemical_compound, ecological system, 0404 agricultural biotechnology, lcsh:Organic chemistry, Drug Discovery, medicine, Alternaria brassicicola, Humans, Food science, Physical and Theoretical Chemistry, glucosinolates, Albatros cultivar, Czech Republic, biology, integrated system, Plant Extracts, head cabbage, fungal infection, Organic Chemistry, Fungi, 04 agricultural and veterinary sciences, target cultivar, Ascorbic acid, biology.organism_classification, 040401 food science, chemistry, Sinigrin, Chemistry (miscellaneous), Glucosinolate, Molecular Medicine, lipids (amino acids, peptides, and proteins), ascorbic acid, 010606 plant biology & botany, Sulforaphane
الوصف: Nutritional value and disease-preventive effects of cabbage are well-known. Levels of the antioxidant compounds ascorbic acid (AA) and glucosinolates (GSL) in new Czech cabbage cultivars were determined in the context of different production systems. The contents of AA and GSLs in cabbage biomass were determined by HPLC. Individual GSLs were identified according to their exact masses with sinigrin used as the external standard. Artificial infection with A. brassicicola generally raised the AA levels. The major GSLs (&ge
10 mg kg&minus
1) were glucobrassicin, sinigrin, and glucoiberin. Indole and aliphatic GSLs were present, but no aromatic ones were detected. Ecological growth conditions and the artificial fungal infection increased the total content of GSLs and, also, of the methoxylated indole GSLs. Sulforaphane, iberin, indole-3-carbinol, and ascorbigen resulting from the hydrolysis of GSLs were found in both cultivars. The amounts and profiles of GSLs present in the two Czech cultivars demonstrated their good nutritional value. The decomposition products sulforaphane, iberin, indole-3-carbinol, and ascorbigen detected improve its health-promoting qualities and represent a suitable component of the human diet.وصف الملف: application/pdf
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