35 research outputs found
Green biomass of perennial crops as valuable source of protein and phytonutrients
Long-term predictable and reliable protein supply for food and feed production is one of the great challenges of today's agriculture both in Hungary and other EU countries. Considering economical, ethical, environmental and ecological aspects of food/feed proteins it is urgent to find alternative sources with technologies besides soy. Among alternative plantbased protein the green biomass has gained an intensive attention. Hungary is self-sufficient in alfalfa and grasses as dedicated green protein source. At the same time green biomass of alfalfa is more than only protein source, it is a rich repository of essential fatty acids and phytonutrients. The quality and quantity of phytochemicals partially depending on the processing of green biomass. After wet fractionation leaf protein concentrate (LPC) as potenital final product can be obtained from the green juice fraction using any coagulation method. The theoretical basis of this process is included in the concept of green biorefinery.
In our work the phytochemical composition of fractionated alfalfa green biomass was evaluated, with special regard to LPC fraction as directly exploitable, protein-rich (40 – 45 m/m% N) feed/food source. UHPLC-ESI-MS was applied to identify different phytonutrients. The phenolic compounds were significant part of the identified compounds. Among flavonoids 2 flavones were dominant mostly in the forms of glucosides. Just few flavone aglycones could be identified such as apigenin and luteolin. Hydroxylated methoxyflavone could be isolated from green juice and fiber fractions. Three isoflavones were found such as ononin; alfalone and formonetin. Nine saponins could be identified and seven unknown saponin aglcyons
The Importance Of Epigenetic Alterations In The Development Of Epstein-Barr Virus-Related Lymphomas
Epstein-Barr virus (EBV), a human gammaherpesvirus, is associated with a series of malignant tumors. These include lymphomas (Burkitt’s lymphoma, Hodgkin’s disease, T/NK-cell lymphoma, post-transplant lymphoproliferative disease, AIDS-associated lymphoma, X-linked lymphoproliferative syndrome), carcinomas (nasopharyngeal carcinoma, gastric carcinoma, carcinomas of major salivary glands, thymic carcinoma, mammary carcinoma) and a sarcoma (leiomyosarcoma). The latent EBV genomes persist in the tumor cells as circular episomes, co-replicating with the cellular DNA once per cell cycle. The expression of latent EBV genes is cell type specific due to the strict epigenetic control of their promoters. DNA methylation, histone modifications and binding of key cellular regulatory proteins contribute to the regulation of alternative promoters for transcripts encoding the nuclear antigens EBNA1 to 6 and affect the activity of promoters for transcripts encoding transmembrane proteins (LMP1, LMP2A, LMP2B). In addition to genes transcribed by RNA polymerase II, there are also two RNA polymerase III transcribed genes in the EBV genome (EBER 1 and 2). The 5′ and internal regulatory sequences of EBER 1 and 2 transcription units are invariably unmethylated. The highly abundant EBER 1 and 2 RNAs are not translated to protein. Based on the cell type specific epigenetic marks associated with latent EBV genomes one can distinguish between viral epigenotypes that differ in transcriptional activity in spite of having an identical (or nearly identical) DNA sequence. Whereas latent EBV genomes are regularly targeted by epigenetic control mechanisms in different cell types, EBV encoded proteins may, in turn, affect the activity of a set of cellular promoters by interacting with the very same epigenetic regulatory machinery. There are EBNA1 binding sites in the human genome. Because high affinity binding of EBNA1 to its recognition sites is known to specify sites of DNA demethylation, we suggest that binding of EBNA1 to its cellular target sites may elicit local demethylation and contribute thereby to the activation of silent cellular promoters. EBNA2 interacts with histone acetyltransferases, and EBNALP (EBNA5) coactivates transcription by displacing histone deacetylase 4 from EBNA2-bound promoter sites. EBNA3C (EBNA6) seems to be associated both with histone acetylases and deacetylases, although in separate complexes. LMP1, a transmembrane protein involved in malignant transformation, can affect both alternative systems of epigenetic memory, DNA methylation and the Polycomb-trithorax group of protein complexes. In epithelial cells LMP1 can up-regulate DNA methyltransferases and, in Hodgkin lymphoma cells, induce the Polycomb group protein Bmi-1. In addition, LMP1 can also modulate cellular gene expression programs by affecting, via the NF-κB pathway, levels of cellular microRNAs miR-146a and miR-155. These interactions may result in epigenetic dysregulation and subsequent cellular dysfunctions that may manifest in or contribute to the development of pathological changes (e.g. initiation and progression of malignant neoplasms, autoimmune phenomena, immunodeficiency). Thus, Epstein-Barr virus, similarly to other viruses and certain bacteria, may induce pathological changes by epigenetic reprogramming of host cells. Elucidation of the epigenetic consequences of EBV-host interactions (within the framework of the emerging new field of patho-epigenetics) may have important implications for therapy and disease prevention, because epigenetic processes are reversible and continuous silencing of EBV genes contributing to patho-epigenetic changes may prevent disease development
Identification of Bioactive Phytochemicals in Leaf Protein Concentrate of Jerusalem Artichoke (Helianthus tuberosus L.)
Jerusalem artichoke (JA) is widely known to have inulin-rich tubers. However, its fresh
aerial biomass produces significant levels of leaf protein and economic bioactive phytochemicals.
We have characterized leaf protein concentrate (JAPC) isolated from green biomass of three Jerusalem
artichoke clones, Alba, Fuseau, and Kalevala, and its nutritional value for the human diet or
animal feeding. The JAPC yield varied from 28.6 to 31.2 g DM k
Refining high-quality leaf protein and valuable co-products from green biomass of Jerusalem artichoke (Helianthus tuberosus L.) for sustainable protein supply
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Comparison of Wet Fractionation Methods for Processing Broccoli Agricultural Wastes and Evaluation of the Nutri-Chemical Values of Obtained Products
The main objective of this study was to increase the economic value of broccoli green agro-waste using three wet fractionation methods in the shadow of green biorefinery and the circular economy. Product candidates were obtained directly by using a mechanical press, and indirectly by using microwave coagulation or via lactic acid fermentation of green juice. The leaf protein concentrates (LPC) fractions displayed significantly higher dry matter content and crude protein content (34–39 m/m% on average) than the green juice fraction (27.4 m/m% on average), without considerable changes in the amino acids composition ratio. UHPLC-ESI-ORBITRAP-MS/MS analysis showed that kaemferol and quercetin are the most abundant flavonols, forming complexes with glycosides and hydroxycinnamic acids in green juice. Lacto-ermentation induced a considerable increase in the quantity of quercetin (48.75 μg·g−1 dry weight) and kaempferol aglycons (895.26 μg·g−1 dry weight) of LPC. In contrast, chlorogenic acid isomers and sulforaphane disappeared from LPC after lactic acid fermentation, while microwave treatment did not cause significant differences. These results confirm that both microwave treatment and lacto-fermentation coagulate and concentrate most of the soluble proteins. Also, these two processes affect the amount of valuable phytochemicals differently, so it should be considered when setting the goal