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Ultrasound as Green Technology for the Valorization of Pumpkin Leaves: Intensification of Protein Recovery
No full textThe recovery of valuable nutritional compounds, like proteins, from waste streams and by-products is a key strategy for enhancing production sustainability and opening up new market potential. This research aimed to use high-intensity ultrasound as an innovative technique to extract the soluble proteins from the pumpkin leaves. The impact of various sonication amplitudes and duration periods on protein yield, functional properties, antioxidant qualities, and structural characteristics, were studied. Utilization of ultrasound technology significantly increased the yield of pumpkin leaf protein by up to 40%—six times higher than maceration. The ultrasound extraction provided a RuBisCO-rich protein fraction with high radical scavenging and chelating activities, especially at 40% amplitude. Cavitation modified the tertiary and secondary structures of leaf proteins: the amount of α-helix changed based on amplitude (12.3–37.7%), the amount of random coil increased to 20.4%, and the amount of β-turn reduced from 31 to 18.6%. The alteration of the protein fluorescence spectrum (blue shift in spectrum) provides further evidence that ultrasound alters the proteins’ molecular structure in comparation with maceration; the maximum tryptophan fluorescence intensity decreased from 22.000 to 17.096. The hydrophobicity values of 76.8–101.5 were substantially higher than the maceration value of 53.4, indicating that ultrasound improved the hydrophobicity of protein surfaces. Ultrasound resulted in a significant increase in solubility in an acidic environment with the increase in sonication amplitude. A 2.4-fold increase in solubility at pH 2 becomes apparent (20% amplitude; 43.1%) versus maceration (18.2%). The emulsifying ability decreases from 6.62 to 5.13 m2/g once the sonication amplitude increases by 20–70%. By combining the ultrasound periods and amplitudes, it is possible to create high-value protein leaf extracts with improved properties which can find real application as food additives and dietary supplements
Multilayer PDDA-based nanocoatings with lignin, pectin and carrageenan decorated with Ag nanoparticles for antibacterial and UV protective cotton fabric
No full textAg nanoparticles (NPs) are well established as extraordinary agents with a broad biocidal activity. Although small amounts of Ag NPs can impart excellent antimicrobial activity to cotton, strong reducing agents commonly applied in their synthesis are not environmentally friendly and hence, a demand for environmentally benign alternative is growing. The impregnation of cotton with Ag NPs usually requires modification of fibers, which can enhance their binding efficiency. The aim of this study was to highlight the influence of coating with different polyelectrolyte combinations possessing the flame retardant potential on the synthesis of Ag NPs, and further on the antimicrobial activity and UV protection of impregnated cotton fabrics. Namely, layer-by-layer deposition of poly (diallyldimethylammonium chloride) (PDDA) in combination with natural polymers lignin, pectin or carrageenan on cotton fabrics was performed. After the sorption of Ag+ ions from 20 mM solution of AgNO3, in situ synthesis of Ag NPs on cotton fabric was accomplished using a gallic acid, as an environmentally friendly reducing agent.
Chemical and morphological changes were assessed by FTIR spectroscopy and FESEM analysis, respectively. Ag NPs were successfully synthesized on all fabricated samples. Unlike in the case of cotton fabric coated with 8 bilayers of PDDA/pectin where single Ag NPs were uniformly scattered over the fiber surface, agglomerated Ag NPs appeared on the surface of cotton fibers coated with 8 bilayers of PDDA/lignin and PDDA/carrageenan.
Antibacterial activity of fabricated textile nanocomposites was tested against Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus. All fabricated samples provided excellent reduction of S. aureus colonies (98-99%) and moderate reduction of E. coli colonies (83.6-96%).
The presence of nanocoatings on cotton fabric significantly improved the UV protection. Cotton fabrics alone did not provide any UV protection. Coating with PDDA/lignin led to extraordinary increase of UPF (~650) and maximum UPF rating of 50+. Coating with PDDA/pectin and PDDA/carrageenan resulted in increase of UV protection but only UPF rating of 50 was reached. Desired UPF rating of 50+ was achieved after subsequent impregnation of these samples with Ag NPs
Xanthene-1,8(2H)-dione as a building block in supramolecular chemistry
No full textA plethora of medicinal and agrochemical applications have made xathene derivatives a popular research topic and the
subject of numerous research papers and dissertations [1]. Xanthene represents an integral part of several marketed drugs
including methantheline bromide (antimuscarinic), propantheline bromide (anticholinergic) and rhodomyrtone (antibacterial)
[2]. In this work, 3,3,6,6-tetramethyl-9-(3-chloro-4-hydroxyphenyl)-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione (1)
and 3,3,6,6-tetramethyl-9-(3,4-dibromo-4-hydroxyphenyl)-3,4,5,6,7,9-hexahydro-1H- xanthene-1,8(2H)-dione (2) (Fig.1),
were synthesized through condensation of dimedone and the appropriate aromatic aldehyde. The single crystal X-ray
analysis revealed that the main structural feature in 1 represents the chains parallel to the a-axis formed by C–H···O
interaction between neighbouring asymmetric units, which are further organised into zipper-like double chains via O–H···O
hydrogen bonds and Cl···π interactions. In 2, alternating asymmetric units are linked by O–H···O hydrogen bonds, C–H···O
and Br···Br interactions into supramolecular chain along the a-axis, while C–H···O and C–H···π interactions led to further
networking. The Hirshfeld surface analysis was used to obtain a preliminary insight into the proportion and nature of the
intermolecular interactions in the crystal structure, while the quantum-chemical calculations of interaction energies identified
dimeric motifs, which represent different recognition modes, with the most significant contribution to the overall energy of
the crystal structure
Bioactivity of gentamicin-loaded hydroxyapatite/poly(vinyl alcohol)/chitosan composite coatings aimed for orthopedic application
No full textFollowing orthopedic surgery, bacterial infection may lead to significant complications related to inflammation in the peri-implant region, including the potential for implant loosening. To address this concern, the surface of metallic implants was modified through the application of bioactive and antibacterial coatings, aiming to mitigate these issues.ExcellMater Conference 2024: Innovative Biomaterials for Novel Medical Devices, Belgrade, Serbia, April 10-12, 202
Established and emerging prebiotics for gut microbiota
No full textThe concept of prebiotics was introduced more than two decades ago, but these bioactive molecules
still represent an attractive area of research. This is due to their close connection with the intestinal microbiota
and, consequently, of the entire human organism. Prebiotics are used as a food source by gut microbes, releasing
various metabolites, of which short-chain fatty acids are key molecules in ensuring the normal functioning of
the colon. Within the framework of this article, an overview of published scientific studies in the last year (from
March 2023 to March 2024), on the impact on the intestinal microbiota residents of two groups of prebiotics
(established and emerging), is given. The prebiotic effect of established prebiotics has been confirmed based
on available in vitro and in vivo studies, while emerging prebiotics’ effect yet needs to be elucidated by in vivo
studies. The available information shows novelties in the field of health benefits and modifications of established
prebiotics, as well as the potential of many polyphenols and polysaccharides from different natural sources to
exhibit prebiotic activity. Presented data give insight into the effect of prebiotics on beneficial and pathogenic
microbes, and potential effective solutions for preserving health and suppressing diseases. A detailed analysis of
the latest scientific publications in this field is of great importance for the food, confectionery, pharmaceutical and
other industries that use prebiotics as an integral part of their products, to improve the quality of existing ones or
to develop new ones
Pholyphenols, antioxidant activity and oxidation stability of cocoa and cocoa products
No full textResearch has shown that cocoa and cocoa products possess polyphenols as major constituents
whose dietary consumption has been associated to beneficial effects. Cocoa and cocoa products,
namely cocoa liquor, cocoa powder and chocolates (milk and dark chocolates) may present
varied polyphenol contents and possess different levels of antioxidant potentials.
The main aim of this research was monitoring changes in total polyphenols content, then
individual polyphenols such as epicatechin and catechin, theobromine, as well as changes in
antioxidant capacity and oxidation stability during chocolate production. We monitored changes
in the following samples: fermented unroasted cocoa beans, roasted cocoa beans, cocoa liquor,
cocoa powder, dark chocolates with 55% cocoa solids and milk chocolate with 36% cocoa solids.
We conducted the tests at the Swisslion chocolate factory situated
factory in Serbia that produces chocolate starting from cocoa beans.
During the process of roasting of cocoa beans, the content of catechin decreased by 29.2%,
epicatechin by 12.2%, theobromine by 10.4%, and total polyphenols by 21.7% compared to
unroasted cocoa beans. In cocoa liquor, we have an additional decreasing of total polyphenols
compared to roasted cocoa beans by 21.1%. Given that in the production of chocolate, except
cocoa raw materials, other raw materials such as milk and sugar are used, the addition of which
causes an additional reduction of polyphenols. In that sense, we got dark chocolate with the
decreased content of total polyphenols compared to cocoa liquor by 65.5%, while in milk
chocolate we got a reduction of 75.1%.
The addition of raw materials and the content of low-fat cocoa parts have a decisive influence on
antioxidant capacity and oxidation stability
Функционални сладолед у праху
No full textФункционални сладолед у праху са укусом ванилина. Сладолед садржи хидролизоване протеине сурутке и инулин, а са овим додацима и измењеном рецептуромје богат извор антиоксиданаса. протеина и влакана и носи следеће нутритивне и здравствене бенефите: извор је протеина, богат извор влакана, LIGHT масти. Протеини доприносе одржавању нормалних костију, одржавању и повећању мишићне масе, инулин из цикорије доприноси нормалном раду црева повећањем учесталости столице
Design and Characterization of Liposomal-Based Carriers for the Encapsulation of Rosa canina Fruit Extract: In Vitro Gastrointestinal Release Behavior
No full textThe increasing demand for natural compounds as an alternative to synthetic antioxidants and conservans has led to the utilization of secondary plant metabolites in the food industry, as these bioactive compounds possess great antioxidative and antimicrobial properties without side effects on human health. Despite this, the sensitivity of plant-derived compounds is a restrictive factor in terms of their full potential. The current research aimed to characterize rosehip-fruit-extract-loaded liposomes (non-treated and UV-irradiated) in terms of their density, surface tension, viscosity, chemical composition (FTIR and HPLC analyses), and thermal behavior. In the storage stability study, the vesicle size, polydispersity index (PDI), zeta potential, conductivity, and mobility of the liposomes were monitored. FTIR analysis confirmed that the plant compounds were successfully loaded within the carrier, while no chemical reaction between the rosehip fruit extract and phospholipids was detected. The results of the HPLC analysis evidence the high potential for liposomal encapsulation to protect sensitive bioactives in the rosehip fruit extract from the degrading effect of UV irradiation. The size of the rosehip-fruit-extract-encapsulated liposomes increased on the seventh day of storage from 250 nm to 300 nm, while the zeta potential values were between −21 mV and −30 mV in the same period and further stabilized over 60 days of monitoring. In Vitro release studies in water and simulated gastrointestinal fluids showed that the presence of enzymes and bile salts (in intestinal fluid) enhanced the rosehip–polyphenol permeability from liposomes (70.3% after 6 h) compared with their release in water after 24 h and in gastric fluid after 4 h (38.9% and 41.4%, respectively). The obtained results indicate that the proliposome method was an effective method for rosehip fruit extract liposomal encapsulation and for the delivery of these plant-derived bioactives in foods
Innovative and Patented Liposome-Based Drug Carriers
No full textLiposome-based drug carriers are multipurpose colloidal drug delivery systems developed mainly for targeted therapy. Researchers have expanded their research on liposomes due to their unique characteristics (e.g., non-toxicity, biodegradability, biocompatibility, and non-immunogenicity). This review summarizes historical advances, from the first scientific papers and patents to the latest inventive solutions, in the field of liposome-based drug carriers and their production processes. Various bibliometric studies on the use of liposomes as drug carriers have been published; nevertheless, they focus on published scientific works rather than patent documents. Patent information is important for the pharmaceutical, nutraceutical, and cosmetic industries because technical knowledge in patent documentation is often not published in any other document. The research in this review was conducted using the Espacenet—European Patent Office database, with keywords and classification codes defined by the International Patent Classification. Innovative formulations, including the usage and administration route, are broadly researched to produce effective and safe drug delivery systems with negligible side effects. Global patenting trends in liposome drug carriers’ production process were also discussed, and this evaluation unifies up-to-date development in this field. Patent database reviews and analyses could help as inspiration for future investigations as well as for problem-solving resources
Valorisation of Blackcurrant Pomace by Extraction of Pectin-Rich Fractions: Structural Characterization and Evaluation as Multifunctional Cosmetic Ingredient
No full textBlackcurrant pomace is a widely available waste stream derived from the industrial production of juice rich in pectin and unextracted polyphenols. Since pectin, an emerging class of gastrointestinal prebiotics, is also a common cosmetic ingredient, the aim of this work was to evaluate blackcurrant pomace as a source of pectin-rich fractions suitable for application in prebiotic cosmetics. Hereby, this raw material was valorised by sequential extraction of acid-soluble (by citric acid, CAP) and Ca-bound (by ammonium oxalate, AOPP) pectic polysaccharides. Both fractions had favourable physicochemical features and a similar degree of methyl-esterification between low- and high-methoxyl pectin (approx. 50%), but CAP had significantly higher galacturonic acid content (72.3%), branching, and purity. Regardless of that, both had very high oil (18.96 mL/g for CAP and 19.32 mL/g for AOPP) and water (9.97 mL/g for CAP and 7.32 mL/g for AOPP)-holding capacities and excellent emulsifying properties, making them promising cosmetic ingredients. The polyphenol content was 10 times higher in CAP, while corresponding antioxidant activity was 3-fold higher. Finally, the influence of varying CAP and AOPP concentrations on common skin pathogen, Staphylococcus aureus, and beneficial skin bacteria, Staphylococcus epidermidis, was examined. The results show significant prebiotic potential of two pectic fractions since they were capable of selectively stimulating S. epidermidis, while S. aureus growth was inhibited, whereas CAP demonstrated a particularly high capacity of up to 2.2, even with methicillin-resistant S. aureus