EKSTRAKCIJA I ANALIZA KONDENZIRANIH TANINA CASTANEA SATIVA MIIL.

Proanthocyanidins, also known as condensed tannins are widespread in woody plants, but are also found in certain forages. Castanea sativa Mill. are exploited for various purposes, but a little is known about potential of this species and possible application in diet and therapy. The parts of chestnut such as: seed, peeled seed, brown seed shell, red internal seed shell, leaves, catkin, spiny bur, as well as the new and old chestnut bark were extracted with 50% ethanol as an extragents. Contents of total phenolics and total flavonoids were measured by application of the standard colorimetric assay. The total condensed tannins content estimated was highest in red internal seed shell 15.29%CE (vanillin assay) and 3.12%CT (acid butanol assay). Also high content of total phenolic compounds and condensed tannins had extracts of catkin, brown seed shell of chestnut and new chestnut bark. Extracts of C. sativa Mill. can be a potential resource of natural tannins with possible application in diet and therapy.Proantocijanidini, poznati kao kondenzirani tanini su jako rasprostranjeni u drvenastim biljkama, a pronađeni su i u hrani. Castanea sativa Mill. se dosta koristi za različite namjene, međutim malo je poznat njegov potencijal i moguća primjena u dijeti i terapiji. Dijelovi kestena kao što su; cijeli plod, srž ploda, vanjska smeđa kora ploda, crvena unutrašnja kora ploda, list, resa, ježura, kao i nova i stara kora drveta su ekstrahirani primjenom 50% etanola kao ekstragensa. Sadržaj ukupnih fenola i flavonoida je određen primjenom standardnih kolorimetrijskih testova. Sadržaj ukupnih kondenziranih tanina je najviši u crvenoj unutrašnjoj kori 15,29%CE (vanilin test) i 3,12%CT (kiseli butanolni test). Visok sadržaj ukupnih fenolnih tvari i kondenziranih tanina je određen u ekstraktima rese, vanjske smeđe kore i nove kore drveta. Ekstrakti C. sativa Mill. mogu biti potencijalna sirovina koja sadrži prirodne tanine sa mogućom primjenom u dijeti i terapiji

KAPACITET EKSTRAKTA PITOMOG KESTENA ZA SUZBIJANJE LIPIDNE PEROKSIDACIJE

Permanent attention of researchers has been focused on the use of natural antioxidants to inhibit lipid peroxidation, or to protect the damage provoked by free radicals. Extracts of sweet chestnut, Lovran’s Marrone cultivar and grafted Italian ″Marrone″ cultivar obtained in two years (2006. and 2007.), were investigated for their capacity to remove lipid peroxidation in liposomes exposed to hydroxyl radical, and for their total phenolics and flavonoids content. Selected tissues of sweet chestnut (Castanea sativa Mill.) fruit, leaf, catkin, spiny burs, young and old bark of chestnut tree have been extracted under the same conditions using 50% ethanol and afterwards dry extracts of examined samples have been gained. All extracts, excluding those with low content of both, total phenolics and flavonoids, showed the ability to protect liposomes from lipid peroxidation. We find practical importance of results in the fact that extract of spiny burs could potentially have beneficial effects in diet of hypertensive patients.Pozornost istraživača plijeni mogućnost korištenja prirodnih antioksidansa u inhibiciji lipidne peroksidacije, ili za zaštitu od oštećenja prouzročenih slobodnim radikalima. U dvogodišnjem razdoblju (2006. i 2007.) istraživan je kapacitet ekstrakta pitomog kestena, kultivara Lovranski marun i cijepljeni Talijanski marun za suzbijanje lipidne peroksidacije na liposomima izloženim hidroksi radikalima, kao i sadržaj fenolnih tvari i flavonoida. Dijelovi ploda kestena (Castanea sativa Mill.), list, resa, ježevica, mlada i stara kora drveta ekstrahirani su pod istim uvjetima korištenjem 50% etanola, a nakon toga je iz istraživanih uzoraka dobiven suhi ekstrakt. Svi ekstrakti, osim onih s malim sadržajem ukupnih fenola i flavonoida, pokazuju sposobnost zaštite liposoma od lipidne peroksidacije. Praktični značaj rezultata istraživanja vidimo u mogućnosti korištenja ekstrakta ježevica u dijeti pacijenata oboljelih od hipertenzije

UKLANJANJE RADIKALA, ANTIMIKROBNA AKTIVNOST I SADRŽAJ FENOLNIH MATERIJA CASTANEA SATIVA EKSTRAKATA

Radical Scavenging and antimicrobial activity of extracts of three cultivar of Castanea Sativa Mill. have been examined. Leaf and catkins have been extracted under the same conditions by 50% ethanol as extragens, afterwards dry extracts of examined samples have been gained. Total phenolic content was determined by HPLC, subsequent to preliminary acid hydrolysis of samples. For determination of extract infl uence to creating and transformation of hydroxide (OH) radicals and (DPPH) radicals, extracts have been dissolved in distillated water and added to Fenton’s model system in concentration of 0.2 mg/ml. High value antioxidant activity (AA) in relation to hydroxyl radicals has turned out catkins from Lovran chestnut (59.09%). The greatest antiradical activity in relation to DPPH radicals occurred with extracts of catkins from domestic sweet chestnut (37.50). The antimicrobial tests have showed that ethanol extracts of leaf and catkins inhibited growth of Gram positive bacteria.Ispitivano je uklanjanje radikala i antimikrobna aktivnost ekstrakata, tri kultivara Castanea Sativa Mill. Lišće i rese su ekstrahirane pod istim uvjetima 50%-tnim etanolom kao ekstragensom, a zatim su dobiveni suhi ekstrakti ispitivanih uzoraka. Nakon izvršene kisele hidrolize uzoraka ukupne fenolne tvari su ordređene HPLC-om. Radi određivanja efekta ekstrakata na stvaranje i transformiranje hidroksil (OH) radikala i (DPPH) radikala, ekstrakti su rastvoreni u destiliranoj vodi i dodani u Fenton-ov model sistem, do fi nalne koncentracije od 0,2 mg/ml. Visoka vrijednost antioksidativne aktivnosti (AA) u odnosu na hidroksil radikale određena je za resu Lovranskog kestena (59,09%). Najveća antiradikalna aktivnost u odnosu na DPPH radikale je utvrđena kod ekstrakta rese domaćeg pitomog kestena (37,50). Antimikrobni test je pokazao da etanolni ekstrakti rese i lista inhibiraju rast Gram pozitivnih bakterija

EPR spin-trapping and spin-probing spectroscopy in assessing antioxidant properties: Example on extracts of catkin, leaves, and spiny burs of castanea sativa

Electron paramagnetic resonance (EPR) spin-trapping and spin-probing techniques were applied to determine antioxidant activity of extracts of catkin, leaves, and spiny burs of Castanea sativa against physiologically relevant reactive species-superoxide and hydroxyl radical generated in simple chemical systems and hydrogen peroxide applied on erythrocytes. Efflux of K + was used as a marker of membrane integrity. Chemical composition of extracts was analyzed using HPLC/DAD and LC/MS. Extracts showed high antioxidative capacity against superoxide but lower activity against hydroxyl radical. They protected fluidity and integrity of membranes of erythrocytes exposed to hydrogen peroxide. Levels of derivatives of ellagitannins showed positive correlation with the antioxidative activity of extracts. Therefore, ellagitannins from chestnut extracts could represent easily accessible natural antioxidants and beneficial component of human diet in pathophysiological conditions related to oxidative stress. In conclusion, EPR spectroscopy represents a valuable tool for evaluation of antioxidant activity in both hydrophilic and lipophilic media

GPCR-targeting nanobodies: attractive research tools, diagnostics, and therapeutics.

G-protein-coupled receptors (GPCRs) represent a major therapeutic target class. A large proportion of marketed drugs exert their effect through modulation of GPCR function, and GPCRs have been successfully targeted with small molecules. Yet, the number of small new molecular entities targeting GPCRs that has been approved as therapeutics in the past decade has been limited. With new and improved immunization-related technologies and advances in GPCR purification and expression techniques, antibody-based targeting of GPCRs has gained attention. The serendipitous discovery of a unique class of heavy chain antibodies (hcAbs) in the sera of camelids may provide novel GPCR-directed therapies. Antigen-binding fragments of hcAbs, also referred to as nanobodies, combine the advantages of both small molecules (e.g., molecular cavity binding, low production costs) and monoclonal antibodies (e.g., high affinity and specificity). Nanobodies are gaining ground as therapeutics and are also starting to find application as diagnostics and as high-quality tools in GPCR research. Herein, we review recent advances in the use of nanobodies in GPCR research. © 2014 Elsevier Ltd. All rights reserved

Bi-specific TCR-anti CD3 redirected T-cell targeting of NY-ESO-1- and LAGE-1-positive tumors

NY-ESO-1 and LAGE-1 are cancer testis antigens with an ideal profile for tumor immunotherapy, combining up-regulation in many cancer types with highly restricted expression in normal tissues and sharing a common HLA-A*0201 epitope, 157–165. Here, we present data to describe the specificity and anti-tumor activity of a bifunctional ImmTAC, comprising a soluble, high-affinity T-cell receptor (TCR) specific for NY-ESO-1157–165 fused to an anti-CD3 scFv. This reagent, ImmTAC-NYE, is shown to kill HLA-A2, antigen-positive tumor cell lines, and freshly isolated HLA-A2- and LAGE-1-positive NSCLC cells. Employing time-domain optical imaging, we demonstrate in vivo targeting of fluorescently labelled high-affinity NYESO-specific TCRs to HLA-A2-, NYESO- 1157–165-positive tumors in xenografted mice. In vivo ImmTAC-NYE efficacy was tested in a tumor model in which human lymphocytes were stably co-engrafted into NSG mice harboring tumor xenografts; efficacy was observed in both tumor prevention and established tumor models using a GFP fluorescence readout. Quantitative RT-PCRwas used to analyze the expression of both NY-ESO-1 and LAGE-1 antigens in 15 normal tissues, 5 cancer cell lines, 10 NSCLC, and 10 ovarian cancer samples. Overall, LAGE-1 RNA was expressed at a greater frequency and at higher levels than NY-ESO-1 in the tumor samples. These data support the clinical utility of ImmTAC-NYE as an immunotherapeutic agent for a variety of cancers