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Opis: Proper processing of natural material is crucial to obtain an extract with high content of biologically active components. Dried, grinded ginger roots were extracted by ultrasonic method and supercritical extraction with CO2 . The aim of the study was to determine if a mixture of the two types of extracts attained by different methods and solvents exhibits better bioavailability than each extract itself. Therefore, both extracts were analytically evaluated and then mixed in a ratio of 1:1. The supercritical extract (SCG extract) and the mixed extract (mixG extract) had high antioxidant activity (78% and 73%) and total phenols (827 mg/g ext. and 1455 mg/g ext.), which is also consistent with the levels of gingerol (303 mg/g ext. and 271 g/g ext.) and shogaol (111 mg/g ext. and 100 g/g ext.) in the extracts. In comparison to both pure extracts higher levels of total phenols were found in the extract mixG. This could be the reason for the significant inhibition of melanoma cells and antimicrobial potential (against Staphylococcus aureus, Escherichia coli, and Candida albicans). The combination of the extracts resulted in a significant increase in the inhibition of selected microbial and melanoma cells WM-266-4 compared to the control. Cell viability decreased below 60% when mixG extract was applied. Antimicrobial activity has been confirmed.
Ključne besede: ginger, supercritical fluid extraction, ultrasound-assisted extraction, antimicrobial activity
Objavljeno v DKUM: 09.05.2025; Ogledov: 0; Prenosov: 0
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Opis: In this research, a new approach to enzyme inactivation in flour was presented by supercritical technology, considered a sustainable technology with lower energy consumption compared to other technologies that use ultra-high temperature processing. Total protein concentration and the activity of enzymes -amylase, lipase, peroxidase, polyphenol oxidase, and protease were determined in flour pre-treated with scCO2. During the study, it was observed that the activity of enzymes such as lipase and polyphenol oxidase, was significantly reduced under certain conditions of scCO2 treatment, while the enzymes -amylase and protease show better stability. In particular, polyphenol oxidase was effectively inactivated below the 60% of preserved activity at 200 bar and 3 h, whereas -amylase under the same conditions retained its activity. Additionally, the moisture content of the scCO2-treated spelt flour was reduced by 5%, and the fat content was reduced by 58%, while the quality of scCO2-treated flour was maintained. In this regard, the sustainable scCO2 process could be a valuable tool for controlling the enzymatic activity of spelt flour since the use of scCO2 technology has a positive effect on the quality of flour, which was verified by the baking performance of spelt flour with the baked spelt bread as an indicator of quality.
Ključne besede: food treatment, spelt flour, proteins, supercritical carbon dioxide, enzyme inactivation, defatted flour, carbon dioxide solubility
Objavljeno v DKUM: 17.04.2025; Ogledov: 0; Prenosov: 1
Celotno besedilo (2,72 MB)
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Opis: In this study, a novel biodegradable poly(lactic-co-glycolic) acid coating containing a model anti-inflammatory drug (ketoprofen) was prepared on TiAl6V4 substrate for use in orthopedic medicine by a two-step process combining drop casting and supercritical CO2-assisted foaming. The prepared coating was first investigated by surface analysis techniques using time-of-flight secondary ion mass spectrometry and X-ray photoelectron spectroscopy. The combined results confirmed the loading of ketoprofen and its homogeneous spatial distribution in the coating. 3D profilometry revealed increased surface roughness of the coating compared to the bare TiAl6V4 substrate, which is favorable for cell adhesion. Furthermore, the electrochemical measurements (i.e., electrochemical impedance spectroscopy and potentiodynamic curve measurements) demonstrated that the coating application significantly mitigated corrosion compared to the bare TiAl6V4 substrate. In vitro drug release tests revealed extended drug release in simulated body fluids with zero-order release kinetics. Finally, the promising cell testing results using adipose-derived mesenchymal stem cells and osteoblasts confirmed the applicability of the coating for implants. Overall, the results of this study highlight the significant potential of the developed bioactive coating for future orthopedic applications.
Ključne besede: TiAlV, bioactive coating, implants, PLGA, supercritical foaming, ketoprofen
Objavljeno v DKUM: 14.03.2025; Ogledov: 0; Prenosov: 4
Celotno besedilo (4,80 MB)

Opis: Cannabinoids are the main active ingredients of Cannabis sativa L., obtained by a suitable extraction method and decarboxylation, in which the acid forms of the cannabinoids are converted into active forms. Supercritical CO2 extraction method and decarboxylation process were optimized for 7 cannabinoids (CBD, CBDA, THC, THCA, CBGA, CBN and CBC). The optimal extraction conditions for all cannabinoids were determined at a temperature of 60 °C and a pressure of 300 bar to 550 bar. At higher temperatures and reaction times, a significant depletion of neutral cannabinoids was observed. The optimal conditions of the decarboxylation process varied depending on the component. For the CBD component, which could be measured in the highest concentrations (560 mg/g), the optimal conditions were 140 °C and 10 min. The study can be an important model for predicting the behavior of cannabinoids under certain parameters.
Ključne besede: supercritical fluids, extraction, cannabinoids, decarboxilation, Cannabis sativa I
Objavljeno v DKUM: 08.01.2025; Ogledov: 0; Prenosov: 7
Celotno besedilo (10,15 MB)

Opis: The 20th European Meeting on Supercritical Fluids (EMSF 2024) was hosted by the Faculty of Chemistry and Chemical Engineering of the University of Maribor from 26 May to 29 May 2024 in Maribor, Slovenia. The EMSF 2024 was a joint event of the International Society for the Advancement of Supercritical Fluids (ISASF) and the European Federation of Chemical Engineering (EFCE) Working Party on High Pressure Technology (WP HPT) Event No. 807. This symposium provided an excellent opportunity for engineers, chemists, physicists, food technologists, and biologists to meet and discuss new ideas, review ongoing challenges, present potential solutions, and identify future issues related to high pressure technologies and supercritical fluids. The aim of the meeting was to deepen connections between researchers, establish new contacts, and promote synergies and partnerships between researchers. The symposium presented the latest advances in high-pressure process technologies that can contribute to the further development of the field.
Ključne besede: supercritical fluids, fundamental data, novel materials, industrial applications, research and development
Objavljeno v DKUM: 24.07.2024; Ogledov: 161; Prenosov: 34
Celotno besedilo (12,44 MB)
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