Among the high value compounds derived from agricultural res

Among the high value compounds derived from agricultural residues there are enzymes with industrial application. The extraction processes have been focused on the development of new strategies that guarantee high recovery rates with maximum activity (Nadar et al., 2017). The residues of these two fruits have been widely used to obtain proteolytic enzymes and other products. Recently, the use of fresh pineapple peels and core in enzymatic and fermentative processes, for obtaining wine and cooking vinegar with antioxidant properties, has been reported (Roda et al., 2017, Roda et al., 2016). In addition to the use of pineapple stems for the extraction of starch with high content of amylose and amylopectin, and higher solubility than cassava or corn starch (Nakthong et al., 2017). Additionally, the extraction of bromelain from fresh peels, core, stem and crown has been evaluated (Ketnawa et al., 2012) and different methods have been applied to obtain purified extracts using biphasic systems (Ketnawa et al., 2010), precipitation methods (Seguí and Fito, 2018) and ultrafiltration methods (Nor et al., 2016). Papaya latex has been used for the extraction of papain. For this purpose precipitation methods with polyethylene glycol and ammonium sulfate have been evaluated (Nitsawang et al., 2006) as well as polyvinyl sulfonate (Braia et al., 2013) and recovery processes of papain using alginate as macro-ligand (Rocha et al., 2016). Other parts of the plant (green fruits, leaves, stems and petioles) have been used to obtain crude extracts with proteolytic activity (Galindo-Estrella et al., 2009). Most of the methods developed for enzyme extraction have focused on the development of aqueous biphasic systems for purification using neutral salts, polymers or ligands (Nadar et al., 2017), similar to those previously described with pineapple and papaya. However, in these cases, only the use of fresh residue for extraction is contemplated, because of the ease with which the enzymes tend to degrade or denature during pretreatment of the same.
Materials and methods
Results and discussion
Conclusions
Acknowledgements
Introduction Functional plasticity of hmg-coa reductase belonging to the innate and adaptive immune system is necessary for the generation of robust immune responses while minimizing detrimental effects toward the host. CD4+ T cell plasticity has been extensively studied in recent years (O’Shea and Paul, 2010). A plasticity index has been proposed for the various T helper cell lineage subsets, with each subset possessing different lineage flexibility (Murphy and Stockinger, 2010). Of the numerous CD4+ T cell subsets, peripherally generated T regulatory (Treg) cells and T helper (Th) 17 cells are regarded as plastic (Bailey-Bucktrout et al., 2013, Boniface et al., 2010, Gagliani et al., 2015, McGeachy et al., 2007, Mukasa et al., 2010, Yang et al., 2008) whereas functional stability has been attributed toward thymic derived Treg (tTreg) cells (Miyao et al., 2012), Th1, and Th2 cell lineages. Both Th2 cells (Adeeku et al., 2008, Hegazy et al., 2010, Peine et al., 2013, Taylor et al., 2006) and tTreg cells (Feng et al., 2014, Laurence et al., 2012, Zhou et al., 2009) have been demonstrated to be plastic in disease conditions. In light of these studies, Th1 cells remain the lineage with the least evidence of functional flexibility. Furthermore, the molecular mechanisms that influence lineage stability in Th1 cells are poorly defined (Brown et al., 2015). In contrast to work on cytokine signaling (O’Shea and Paul, 2010), the role of co-receptors in mediating functional plasticity has received minimal attention. One such co-inhibitory molecule that has been implicated in Th cell plasticity is programmed death ligand-1 (PDL-1 or B7-H1). In our previous work, we have found that PDL-1 can induce Foxp3 in human Th1 cells (Amarnath et al., 2011), consistent with work in murine naive T cells (Francisco et al., 2009). In the tumor microenvironment, PDL-1 expression coincides with increased intra-tumor Foxp3+ T cells (Duraiswamy et al., 2013, Jacobs et al., 2009), suggesting that PDL-1 may play a role in maintaining Foxp3 expression in CD4+ Th cell subsets. PDL-1 binds to its receptor PD-1 on T cells which signals through the inhibitory phosphatase SHP1 (Chemnitz et al., 2004). SHP1 or SHP2 recruitment results in STAT de-phosphorylation (Amarnath et al., 2011, Taylor et al., 2017), potentially destabilizing the transcriptional signature of Th1 cell lineage.