24 research outputs found
Exquisite wild mushrooms as a source of dietary fiber: analysis in electron-beam irradiated samples
In the present study, electron-beam irradiation was applied to dried samples of Boletus edulis and Macrolepiota procera to evaluate the effects on their fiber composition. Both species presented an important percentage of dietary fiber, soluble and insoluble in different ratios. These high fiber levels are an interesting feature, allowing considering mushrooms as an alternative source of dietary fibers in the highly competitive market of fiber-enriched food products. In B. edulis samples, insoluble fiber and total fiber amounts were significantly lower in samples irradiated with 10 kGy, but soluble fiber had no significant changes for any of the assayed doses, while total available carbohydrates were significantly lower in unirradiated samples. M. procera samples irradiated with 6 kGy presented less total fiber, insoluble fiber and carbohydrates, but the same dose allowed the highest contents in soluble dietary fiber. In general, the irradiated samples, especially for higher doses, gave some significant changes in the total available carbohydrates and dietary fibers content. Nevertheless, the resulting differences still allow considering these species as good natural fiber sources, maintaining their potential health effects, while promoting a clean way to disinfest and decontaminate these highly perishable products.Authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support to research centres CIMO (PEst-OE/AGR/UI0690/2011), REQUIMTE (PEst-C/EQB/LA0006/2011) and ALIMNOVA research group from UCM. Ă‚. Fernandes and J.C.M. Barreira thank FCT, POPH-QREN and FSE for their grants (SFRH/BD/76019/2011 and SFRH/BPD/72802/2010, respectively). Dr. A. Rafalski, for e-beam irradiations and Prof. A. Chmielewski, General Director of the Institute of Nuclear Chemistry and Technology, Warsaw, Poland, for allowing e-beam irradiations
Effects of gamma irradiation on macro and microelements of Boletus edulis Bull.: Fr. and Hydnum repandum L.: Fr.
Mushrooms are considered excellent sources of minerals, being necessary to know the levels of essential elements in the edible species [1]. Mineral elements are classified in macro (e.g., Ca, Mg, Na, K) and microelements (e.g., Fe, Cu, Mn, Zn) with functions that include maintaining acid-base balance, osmotic regulation, oxygen transport and enzymatic cofactors [2-3]. Mushrooms need special caution in their conservation. Accordingly, treatments such as gamma rays have been applied to improve their shelf life and reduce health hazards caused by pathogenic microorganisms [4]. In this work, gamma irradiation was applied to Boletus edulis Bull.: Fr. and Hydnum repandum L.: Fr. to assess the effects on the minerals composition. The fruiting bodies were collected in Trás-os-Montes (Northeast of Portugal) in November 2012. Fresh samples were irradiated in experimental equipment with four 60Co sources, at 1 and 2 kGy. The studied mushrooms presented high levels of macro and microelements. Up to the applied doses, some significant differences were observed. However, in most cases, changes did not follow a marked tendency, being more likely to be derived from the natural variability in mineral accumulation as a result of mushroom growth in different ecosystems. Hence, irradiation treatment, using gamma rays up to 2 kGy, is a suitable technique to disinfest and/or decontaminate wild mushrooms, independently of their species or physical state
Electron-beam irradiation at low doses preserves dietary fiber content in Boletus edulis Bull.: Fr. wild mushroom
Mushrooms are considered a good source of non-digestible carbohydrates, which represent a group of dietary fiber with various beneficial health effects to humans e.g., improve the function of the alimentary tract, helps lower postprandrial blood glucose, insuline and cholesterol, strengthens the immune system and antitumor activity [1]. Due to delicate nature, mushrooms suffer severe conservation problems and have to be processed to extend their short shelf-life. Drying is one of the most used processes for preserving mushrooms and, for decontamination, electron-beam irradiation also proved its technological feasibility to be safely used for reduce food losses [2]. In the present study, electron-beam irradiation (2, 6 and 10 kGy) was applied to dried samples of Boletus edulis Bull.: Fr. in order to evaluate the effects on fiber composition. The fruiting bodies were collected in Trás-os-Montes (Northeast of Portugal) in November 2012 and dried at 30 ºC in an oven. The irradiation was performed at the Institute of Nuclear Chemistry and Technology, in Warsaw, Poland. The determination of total available carbohydrate was carried out by the Anthrone method [3]. AOAC enzymatic-gravimetric methods, 993.19 and 991.42 were used for soluble and insoluble dietary fiber analysis [4]. B. edulis presented an important percentage of dietary fiber, soluble and insoluble in different ratios. The irradiated samples, especially for higher doses, gave some significant changes in total available carbohydrates and dietary fibers content; but, a lower dose (2 kGy) preserves carbohydrates, soluble and insoluble fiber content. Electron-beam irradiation at low doses is a feasible choice to extend mushrooms shelf-life and preserves the dietary fiber content.FCT and COMPETE/QREN/UE- strategic projects PEst-OE/AGR/UI0690/2011 (CIMO) and PEst-C/EQB/LA0006/2011 (REQUIMTE); grant SFRH/BD/76019/2011 to A. Fernandes and SFRH/BPD/72802/2010 to J. Barreir
Stability of total folates/vitamin B9 in irradiated watercress and buckler sorrel during refrigerated storage
The suitability of post-packaging gamma radiation treatment for preserving total folates or vitamin B9 in watercress (Nasturtium officinale R. Br.) and buckler sorrel (Rumex induratus Boiss. & Reut.) during storage at 4 °C was evaluated. Comparable amounts of total folates were found in fresh, non-stored samples of both species. In watercress, the irradiation treatment of up to 5 kGy reduced the loss of total folates caused by 7 days of storage. In turn, the 12-day storage period did not affect the total folate content of buckler sorrel (while the 2 kGy dose decreased the initial levels), evidencing that packaging and refrigeration are enough for preservation. These results suggest that the suitability of post-packaging irradiation for preserving total folates may depend not only on the applied dose but also on the plant matrix under analysis. In addition, new data useful to complete food composition tables or databases is provided.The authors are grateful to the Foundation for Science and Technology ( FCT , Portugal) and FEDER under Programme PT2020 for financial support to CIMO ( UID/AGR/00690/2013 ), REQUIMTE/LAQV ( UID/QUI/50006/2013 – POCI/01/0145/FERDER/007265) and C2TN ( UID/Multi/04349/2013 ) and the Grant of J. Pinela (UID/AGR/00690/2013_DNAABN); and to the ALIMNOVA Research Group (Project UCM-252/2017).info:eu-repo/semantics/publishedVersio
SOCS2 Influences LPS Induced Human Monocyte-Derived Dendritic Cell Maturation
Dendritic cells (DCs) are highly specific antigen presenting cells, which link innate and adaptive immune responses and participate in protecting hosts from invading pathogens. DCs can be generated in vitro by culturing human monocytes with GM-CSF and IL-4 followed by LPS induced DC maturation. We set out to study the suppressor of cytokine signaling (SOCS) proteins during maturation and activation of human monocyte-derived DCs from peripheral blood in vitro. We found that the expression of SOCS2 mRNA and protein is dramatically up-regulated during DC maturation. Silencing of SOCS2 using siRNA, inhibited DC maturation as evidenced by a decreased expression of maturation markers such as CD83, co-stimulatory molecules CD40, CD86 and HLA-DR. Furthermore, silencing of SOCS2 decreased LPS induced activation of MAP kinases (SAKP/JNK, p38, ERK), IRF3, decreased the translocation of the NF-ÎşB transcription factor and reduced downstream gene mRNA expression. These results suggest a role for SOCS2 in the MyD88-dependent and -independent TLR4 signaling pathways. In conclusion, our results demonstrate that SOCS2 is required for appropriate TLR4 signaling in maturating human DCs via both the MyD88-dependent and -independent signaling pathway
Influence of Neonatal Hypothyroidism on Hepatic Gene Expression and Lipid Metabolism in Adulthood
Thyroid hormones are required for normal growth and development in mammals. Congenital-neonatal hypothyroidism (CH) has a profound impact on physiology, but its specific influence in liver is less understood. Here, we studied how CH influences the liver gene expression program in adulthood. Pregnant rats were given the antithyroid drug methimazole (MMI) from GD12 until PND30 to induce CH in male offspring. Growth defects due to CH were evident as reductions in body weight and tail length from the second week of life. Once the MMI treatment was discontinued, the feed efficiency increased in CH, and this was accompanied by significant catch-up growth. On PND80, significant reductions in body mass, tail length, and circulating IGF-I levels remained in CH rats. Conversely, the mRNA levels of known GH target genes were significantly upregulated. The serum levels of thyroid hormones, cholesterol, and triglycerides showed no significant differences. In contrast, CH rats showed significant changes in the expression of hepatic genes involved in lipid metabolism, including an increased transcription of PPARα and a reduced expression of genes involved in fatty acid and cholesterol uptake, cellular sterol efflux, triglyceride assembly, bile acid synthesis, and lipogenesis. These changes were associated with a decrease of intrahepatic lipids. Finally, CH rats responded to the onset of hypothyroidism in adulthood with a reduction of serum fatty acids and hepatic cholesteryl esters and to T3 replacement with an enhanced activation of malic enzyme. In summary, we provide in vivo evidence that neonatal hypothyroidism influences the hepatic transcriptional program and tissue sensitivity to hormone treatment in adulthood. This highlights the critical role that a euthyroid state during development plays on normal liver physiology in adulthood
New foods: a case study of Portuguese “Serra da Estrela” cheese incorporated with chestnuts flowers
The “Serra da Estrela” is the most well-known Portuguese cheese, made from ewe’s milk for
centuries, granted a Protected Designation of Origin (PDO) in 1996 by the European Union. To this date, not
many studies have been carried out regarding the nutritional profile of this cheese. Chestnut flowers are usually
leftovers of the nut harvest, and, being a very interesting flower in terms of antioxidants and antimicrobials, the
incorporation of this by-product into the cheese may be of interest to both the farmers and food industry. For
one, it could become an additional source of income for the agrarian, while being a natural antimicrobial and
antioxidant, reducing the need of chemical conservatives, which is a growing concern among the food industries.
Herein, nutritional profiles of three samples are reported: control cheese, cheese incorporated with lyophilized
powdered flower and cheese incorporated with lyophilized flower decoction. The main differences regarding
macronutrients composition and energetic value will be assessed, along with an overview of individual free
sugars, tocopherols and fatty acids
Gene expression profile of the aging process in rat liver: Normalizing effects of growth hormone replacement
The mechanisms that control life span and age-related phenotypes are not well understood. It has been suggested that aging or at least some of its symptoms are related to a physiological decline in GH levels with age. To test this hypothesis, and to improve our understanding of the cellular and molecular mechanisms behind the aging process, we have analyzed age-induced changes in gene expression patterns through the application of DNA chip technology. In the present study, the aging process was analyzed in rat liver in the presence or absence of GH replacement. Out of 3,000 genes printed on the microarrays, approximately 1,000 were detected in the rat liver. Among these, 47 unique transcripts were affected by the aging process in male rat livers. The largest groups of age-regulated transcripts encoded proteins involved in intermediary metabolism, mitochondrial respiration, and drug metabolism. Approximately 40% of the differentially expressed gene products were normalized after GH treatment. The majority of those transcripts have previously not been shown to be under GH control. The list of gene products that showed normalized expression levels in GH-treated old rats may shed further insight on the action and mechanism behind the positive effects of GH on, for example, fuel metabolism and body composition observed in different animal and human studies