This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Highlights • Uptake of carnosic acid and carnosol from rosemary supercritical extract. • Basolate... more Highlights • Uptake of carnosic acid and carnosol from rosemary supercritical extract. • Basolateral fraction of the extract showed an important anti-inflammatory activity. • The extract could be used in formulations for prevention of inflammatory diseases.
International Biodeterioration & Biodegradation, Oct 1, 2010
Seven Oyster mushroom strains were cultivated in wheat straw (WS) bags supplemented with 0 up to ... more Seven Oyster mushroom strains were cultivated in wheat straw (WS) bags supplemented with 0 up to 90% olive mill waste (OMW), a solid residue obtained from a two-phases olive oil production system. All mushroom strains could grow but high OMW concentrations resulted in a significant yield, biological efficiency and productivity decrease, retarding of pinning and flushing and loss of fruiting bodies quality. However, most of the mushroom strains showed no significant differences on cultivation parameters and fruiting bodies quality (except for colour) between control (WS) substrates or substrates supplemented up to 50% OMW (w/w). Addition of 50% OMW to WS substrates turned mushrooms lighter and less reddish. This colour shift was not due to enzymatic oxidations or inhibition since laccase and peroxidase activities were not differing from control. Total phenolic content and antioxidant activity were also similar and no phenolic compounds from OMW were detected in the fruiting bodies. Some of the analysed Pleurotus strains were better suited to grow on OMW supplemented substrates than others.
Heat-induced unfolding facilitates plant protein digestibility during in vitro static infant digestion
Food Chemistry, May 1, 2022
Soy protein is the main protein source for plant-based infant formula, whereas pea protein is con... more Soy protein is the main protein source for plant-based infant formula, whereas pea protein is considered as a potential alternative plant protein source. This study assessed the structural changes of soy and pea proteins after heating between 65 °C and 100 °C, and its effects on the in vitro digestibility in the context of infant digestion. We found that with increased heating intensity, both soy and pea proteins unfolded, manifested as the increased surface hydrophobicity, thereby potentially improving the accessibility to digestive enzymes. Their final in vitro digestibility increased from ∼ 30% of non-treated samples to ∼ 60% of 100 °C-heated samples for soy protein, and from ∼ 52% to ∼ 65% for pea protein. Surface hydrophobicity was strongly positively correlated to the overall digestibility. Therefore, the heating temperatures that enabled protein unfolding promoted the digestibility of soy and pea proteins under infant digestion conditions.
ScopeChitin, the most abundant polysaccharide found in nature after cellulose, is known for its a... more ScopeChitin, the most abundant polysaccharide found in nature after cellulose, is known for its ability to support wound healing and to lower plasma‐oxidized low‐density lipoprotein (LDL) levels. Studies have also revealed immunomodulatory potential but contradicting results are often impossible to coalesce through usage of chitin of different or unknown physicochemical consistency. In addition, only a limited set of cellular models have been used to test the bioactivity of chitin.Methods and ResultsChitin is investigated with well‐defined physicochemical consistency for its immunomodulatory potency using THP‐1 macrophages, impact on intestinal epithelial barrier using Caco‐2 cells, and fermentation by fecal‐derived microbiota. Results show that chitin with a degree of acetylation (DA) of ≈83%, regardless of size, does not affect the intestinal epithelial barrier integrity. Large‐sized chitin significantly increases acetic acid production by gut microbiota without altering the compo...
Heat treatment of β-lactoglobulin affects its digestion and translocation in the upper digestive tract
Food Chemistry, 2020
Heat treatment is a commonly applied unit operation in the processing of β-lactoglobulin containi... more Heat treatment is a commonly applied unit operation in the processing of β-lactoglobulin containing products. This does, however, influence its structure and thereby impacts its activity and digestibility. We describe how various heat-treatments of β-lactoglobulin change the digestibility using a modified version of the current consensus INFOGEST protocol. Additionally, protein was investigated for its translocation over the intestinal epithelial barrier, which would bring them in contact with immune cells. The extent of gastric digestibility was higher when the protein structure was more modified, while the influence of glycation with lactose was limited. Translocation studies of protein across Caco-2 cell monolayers showed a lower translocation rate of protein heated in solution compared to the others. Our study indicates that structural modifications after different heat-treatments of β-lactoglobulin increase in particular gastric digestibility and the translocation efficiency across intestinal epithelial cells.
Introduction: Adoptive T-cell treatments of solid cancers have evolved into a robust therapy with... more Introduction: Adoptive T-cell treatments of solid cancers have evolved into a robust therapy with objective response rates surpassing those of standardized treatments. Unfortunately, only a limited fraction of patients shows durable responses, which is considered to be due to a T cell-suppressive tumor microenvironment (TME). Here we argue that naturally occurring β-glucans can enable reversion of such T cell suppression by engaging innate immune cells and enhancing numbers and function of lymphocyte effectors. Areas covered: This review summarizes timely reports with respect to absorption, trafficking and immune stimulatory effects of β-glucans, particularly in relation to innate immune cells. Furthermore, we list effects toward well-being and immune functions in healthy subjects as well as cancer patients treated with orally administered β-glucans, extended with effects of β-glucan treatments in mouse cancer models. Expert opinion: Beta-glucans, when present in food and following uptake in the proximal gut, stimulate immune cells present in gut-associated lymphoid tissue and initiate highly conserved proinflammatory pathways. When tested in mouse cancer models, β-glucans result in better control of tumor growth and shift the TME toward a T cell-sensitive environment. Along these lines, we advocate that intake of β-glucans provides an accessible and immune-potentiating adjuvant when combined with adoptive T-cell treatments of cancer.
In vivo studies suggest that intestinal barrier integrity is dependent on mitochondrial ATP produ... more In vivo studies suggest that intestinal barrier integrity is dependent on mitochondrial ATP production. Here, we aim to provide mechanistic support, using an in vitro model mimicking the oxidative in vivo situation. Methods: Human Caco-2 cells were cultured for 10 days in culture flasks or for 14 days on transwell inserts in either glucose-containing or galactose-containing medium. Mitochondria were visualized and cellular respiration and levels of oxidative phosphorylation (OXPHOS) proteins were determined. Mitochondrial ATP depletion was induced using CCCP, rotenone, or piericidin A (PA). Monolayer permeability was assessed using transepithelial electrical resistance (TEER) and fluorescein flux. Gene expression and cellular distribution of tight junction proteins were analyzed. Results: Caco-2 cells cultured in galactose-containing, but not in glucose-containing, medium showed increased mitochondrial connectivity, oxygen consumption rates and levels of OXPHOS proteins. Inhibition of mitochondrial ATP production using CCCP, rotenone or PA resulted in a dose-dependent increase in Caco-2 monolayer permeability. In-depth studies with PA showed a six fold decrease in cellular ATP and revealed increased gene expression of tight junction proteins (TJP) 1 and 2, occludin, and claudin 1, but decreased gene expression of claudin 2 and 7. Of these, claudin 7 was clearly redistributed from the cellular membrane into the cytoplasm, while the others were not (TJP1, occludin) or slightly (claudin 2, actin) affected. In vivo studies suggest that intestinal barrier integrity is dependent on mitochondrial ATP production. Here, we aim to provide mechanistic support, using an in vitro model mimicking the oxidative in vivo situation. Conclusions: Well-functioning mitochondria are essential for maintaining cellular energy status and monolayer integrity of galactose grown Caco-2 cells. Energy depletion-induced Caco-2 monolayer permeability may be facilitated by changes in the distribution of claudin 7.
Tyrosinase‐related protein 1 (TYRP1) is one of three tyrosinase‐like glycoenzymes in human melano... more Tyrosinase‐related protein 1 (TYRP1) is one of three tyrosinase‐like glycoenzymes in human melanocytes that are key to the production of melanin, the compound responsible for the pigmentation of skin, eye, and hair. Difficulties with producing these enzymes in pure form have hampered the understanding of their activity and the effect of mutations that cause albinism and pigmentation disorders. Herein we show that the typical tyrosinase‐like subdomain of TYRP1 contains two zinc ions in the active site instead of copper ions as found in tyrosinases, which explains why TYRP1 does not exhibit tyrosinase redox activity. In addition, the structures reveal for the first time that the Cys‐rich subdomain, which is unique to vertebrate melanogenic proteins, has an epidermal growth factor‐like fold and is tightly associated with the tyrosinase subdomain. Our structures suggest that most albinism‐related mutations of TYRP1 affect its stability or activity.
Anti-freeze proteins: characteristics, mechanism of action and applications
Antivrieseiwitten hebben de eigenschap om het vriespunt te verlagen en rekristallisatie van ijs t... more Antivrieseiwitten hebben de eigenschap om het vriespunt te verlagen en rekristallisatie van ijs tegen te gaan. Deze eiwitten komen voor in poolvissen, insekten, planten en micro-organismen. Bovendien geven ze de ijskristallen een andere morfologie
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