Sida hermaphrodita seeds as the source of anti - Candida albicans activity.

Sida hermaphrodita is a perennial herbaceous plant with potential economic importance; however, there is no information about its antimicrobial properties. The aim of our study was to analyze the morphology and metabolic activity of Candida albicans cells after exposure to the extract from S. hermaphrodita seeds, determine its cytotoxicity against human skin fibroblasts and carry out chemical analysis of the extract. Microscopic analysis showed that the crude seed extract (CSE) caused a significant decrease in the metabolic activity of fungal cells, clear cell deformation, and budding disturbances. The analysis of cytotoxicity showed no influence of the extract on the fibroblasts. The CSE and seed extract after dialysis (DSE) were analyzed using electrophoretic, chromatographic, and spectroscopic methods. SDS-PAGE electrophoresis showed the presence of proteins and carbohydrate compounds in the extract. The Raman spectroscopy analysis of the DSE confirmed the presence of proteins, while FTIR analyses revealed the occurrence of albumin-type proteins. The NMR and GC-MS analyses showed the presence of carbohydrates in the seed extract. The MALDI and ESI LC-MS/MS analysis of the CSE and the DSE fractions revealed the occurrence of vicilin-type and plant lipid transfer proteins. The seed extract is a promising formulation to use in C. albicans infections.

Analysis of AGP contribution to the dynamic assembly and mechanical properties of cell wall during pollen tube growth.

Arabinogalactan proteins as cell wall structural proteins are involved in fundamental processes during plant development and growth. The aim of this study was to evaluate AGP function in the distribution of pectin, cellulose and callose along Fragaria x ananassa pollen tube and to associate the cell wall structure with local mechanical properties. We used Yariv reagent which interacts with AGPs and allows the observation of the assembly of cell walls without AGPs performing their function. Cytochemical, immunofluorescence labelling and atomic force microscope have been used to characterize the changes in cell wall structure and stiffness. It was shown that disordering of the structure of AGP present in cell walls affects the localization of cellulose, pectins and the secretion of callose. Changes in cell wall assembly are relevant to pollen tube mechanical properties. The stiffness gradient lengthwise through the axis of the pollen tube has demonstrated a significantly higher Young's modulus of the shank region than the growth zone. It has been revealed that the apex of the pollen tube cultured in the presence of Yariv reagent is stiffer (1.68 MPa) than the corresponding region of the pollen tube grown under control conditions (0.13-0.27 MPa). AGP affects the structure of the cell wall by changing the distribution of other components and the modification of their localization, and hence it plays a significant role in the mechanical properties of the cell wall.

Structural network of arabinogalactan proteins (AGPs) and pectins in apple fruit during ripening and senescence processes.

The cell wall is an essential framework determining the overall form of the plant cell. Our study was focused on the distribution of arabinogalactan proteins (AGPs), arabinan, and homogalacturonan in fruit cells during ripening and storage with emphasis on quantitative analysis of their presence in particular regions of the cell wall - plasma membrane. The localization of the examined compounds was determined with immunohistochemistry techniques and immunogold labelling. Spatio-temporal colocalization between AGPs epitopes - [ßGlcA(1→3)-αGalA(1→2)Rha] recognized by JIM13 and MAC207 antibodies, and arabinan labelled by the LM16 antibody was detected in the inner cell wall layer, in association with the plasma membrane. The specific arrangement of AGP and arabinan epitopes differentiated them from homogalacturonan epitopes, consisting of GalA residues recognized by LM19 and LM20 antibodies in all the examined fruit maturity stages. The disruption of cell wall - plasma membrane continuum, observed during ripening-associated softening process, was associated with both the substantial decrease of AGPs, pectins content and with remodeling of their arrangement. The results indicate that the textural properties of fruit during growth and postharvest storage, an attribute of fruit quality becoming selection criteria for consumers, depend on the existence of dynamic network organizing polysaccharides and glycoproteins in the extracellular matrix.

Analysis of antifungal and anticancer effects of the extract from Pelargonium zonale.

The extract from Pelargonium zonale stalks exhibits activity against Candida albicans and exerts an effect on the HeLa cell line. The action against C. albicans cells was analysed using light, CLSM, SEM, and TEM microscopes. The observations indicate that the extract influenced fungal cell morphology and cell metabolic activity. The morphological changes include cell wall damage, deformations of cell surfaces, and abnormalities in fungal cell shape and size. Cells of C. albicans treated with the extract exhibited disturbances in the budding pattern and a tendency to form agglomerates and multicellular chains. The P. zonale extract caused a significant decrease in the metabolic activity of C. albicans cells. Cells died via both apoptosis and necrosis. The antitumor activity of the extract was analysed using the MTT assay. The P. zonale extract exhibited minor cytotoxicity against the HeLa cell line but a dose-dependent cytopathic effect was noticed. The P. zonale extract is a promising source for the isolation of antifungal and anticancer compounds.