The isolation of lectins by affinity chromatography with crosslinked hemicelluloses has been a common practice because of the variety of glycosides that they present, improving the isolation of different kinds of lectins, such as the galactose ligands.Lectins affinity for carbohydrates is so specific that a simple configuration of the chiral carbon can affect affinity, and there are lectins that are more related to alfa-galactosidic than beta-galactosidic residues, setting up that way, an anomeric recognition.The anomeric configuration of galactose residuesseems to have biological importance related to the behavior of some diseases and physiological processes. This work aimed to assess the anomeric recognition of two lectins reported as β-galactose ligands (PNA and ricin) and two lectins reported as α-galactose ligands (frutalin and jacalin) in two types of hemicellulose (xyloglucan of Tamarindus indica and galactomannan of Caesalpinia pulcherrima), subsequently crosslinked and used as chromatographic matrices. As a result,chromatographic profiles and retained fractions suggested preferential anomeric recognition by lectins for the hemicelluloses crosslinked. The galactomannan matrix retained 0,5mg of PNA lectin and 2,3mg of ricin lectin; meanwhile, the xyloglucan matrix retained 3,4mg of PNA and 3,2mg of ricin; results obtained by applying 5 mg of lectin. Ricin expresses a visible flexibility in anomeric recognition, while PNA shows a restricted recognition of β-galactose residues.Frutalin and jacalin did not show recognition of the xyloglucan matrix. This work proposes using hemicellulose reticles with epichlorohydrin as affinity chromatographic matrices for anomeric studies on recognizing galactose binding lectins.

The clay mineral associations in the Cretaceous-Tertiary Boundary (KTB) and in the Danian and Maastrichtian levels of sections from the Mediterranean and the Atlantic Domains have been studied. The Mediterranean sections have a single mineral association consisting of smectiteiltite and kaolinite, whereas the Atlantic sections have several associations: illite-chlorite, illite-R1 I-S-kaolinite and illite-R 1 I-S-chlorite. Data are presented relating to the influence of K-feldspars and Fe oxide sphemles on the clay mineral associations. Study of rare-earth elements shows that regional geological factors affect the clay mineralogy of the KTB, examples showing significant anthigenesis in the Mediterranean sections, and important detrital supply in all the Atlantic sections. We propose that the KTB studied in these marine sections is equivalent to the uppermost layer of the two-layered clay unit originating in a cloud of a vapourized bolide. Regional tectonic conditions have been responsible for differences in clay sedimentation in these geological domains and among the stratigraphic sections of the Atlantic Domain.

Non-absorbable glucids (NAG) like active hexose correlated compound (AHCC), inulin or fructooligosaccharides (FOS) are known to act as prebiotics, but they could exert different actions independent of their prebiotic activity. Here, we have tested the hypothesis that AHCC, inulin or FOS can regulate cytokine production in monocytes and enterocytes and induce differentiation in enterocytes in a prebiotic independent way.AHCC is a product prepared from the mycelium of edible Basidiomycete fungi that contains oligosaccharides (74 %), considered the main active ingredient of this product, Of these, nearly 20 % are partially acetylated alpha-1, 4 glucans. To test the influence of AHCC, inulin and FOS on IL-1b, IL-8 and TNF production by monocytes and the effect on enterocyte IL-8 production we added them (0.1-5 g/l of culture medium) to THP-1 cells, human peripheral blood monocytes, HT-29 cells and Caco-2 cells cultured to confluency and 1 week after confluency. The effects of lipopolysaccharide (LPS) added to the culture medium was also studied. After the addition of the products, cells were incubated for 24 h and cytokines were measured in the culture medium by ELISA. The involvement of the MAPK and the NFkB signalling pathways was studied adding different inhibitors (PD98059 for the MAPK ERK1/2, SB203580 for p38 MAPK, SP600125 for c-Jun N-terminal kinase (JNK) and Bay11-7082 for IkBa) to the cell culture medium 1 h before the products. Translocation of p50 and p65 to the nucleus was also studied. Confluent Caco-2 cells were used to study the effect of AHCC on disaccharidase and alkaline phosphatase activities as markers of intestinal differentiation.Our results show that AHCC increases the production of all the cytokines studied, while inulin and FOS only increase the production of IL-8. The effects of all the products assayed is dependent on both the effect on the MAPK and the NF-kB signalling pathways (Fig. 1). On the other hand, our results indicate that AHCC has no effect in the production of IL-8 either in HT-29 or Caco-2 cells in basal conditions. Nevertheless in both cell lines it inhibits IL-8 production after LPS stimulation. This effect is independent of the NF-kB signalling pathway since no decrease in IkB phosphorylation of nuclear p50 or p65 levels was observed in HT-29 cells. On the other hand AHCC added to confluent Caco-2 cells led to an increase in the activities of lactase, sucrase and maltase.The NAG tested stimulates the production of cytokines in monocytes, although AHCC exhibits a broader stimulatory effect. Furthermore, AHCC inhibits enterocyte IL-8 production after LPS stimulation and could induce enterocyte differentiation. In conclusion, our results indicate that NAG exert immunomodulatory and pro differentiation effects that are independent of their prebiotic actions. Therefore, our work describes a new mechanisms of action of NAG.

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