Multivariate analysis for FTIR in understanding treatment of used cooking oil using activated carbon prepared from olive stone.

In this study, activated carbons prepared from the green and black olive stone (green OSAC and black OSAC) were used as adsorbents to investigate their removal efficiencies for oxidation products and polar compounds from used sunflower and corn cooking oils. The degree of oxidation level and polar compounds were evaluated using Fourier transform infrared (FTIR) with the principal component analysis and ultra-performance liquid chromatography. Two FTIR absorption peaks were used for the oil evaluation, namely 3007-3009 cm-1, which is related to C-H symmetric stretching vibration of the cis double bonds, and ~1743 cm-1, which is related to = CH and ester carbonyl stretching vibration of the functional groups of the triglycerides, C = O. The principal component analysis results showed significant variations in the oxidation level of the sunflower and the corn oils occurred after consecutive heating and French fries frying for 10 days. The oxidation products that are adsorbed on the surface of the OSAC forms π-complexes with the C = C parts of the OSAC system. It can be concluded that the prepared adsorbents can be promising, efficient, economically effective, and environmentally friendly alternative adsorbents for oil treatment applications.

Olive seed protein bodies store degrading enzymes involved in mobilization of oil bodies.

The major seed storage reserves in oilseeds are accumulated in protein bodies and oil bodies, and serve as an energy, carbon, and nitrogen source during germination. Here, the spatio-temporal relationships between protein bodies and several key enzymes (phospholipase A, lipase, and lipoxygenase) involved in storage lipid mobilization in cotyledon cells was analysed during in vitro seed germination. Enzyme activities were assayed in-gel and their cellular localization were determined using microscopy techniques. At seed maturity, phospholipase A and triacylglycerol lipase activities were found exclusively in protein bodies. However, after seed imbibition, these activities were shifted to the cytoplasm and the surface of the oil bodies. The activity of neutral lipases was detected by using α-naphthyl palmitate and it was associated mainly with protein bodies during the whole course of germination. This pattern of distribution was highly similar to the localization of neutral lipids, which progressively appeared in protein bodies. Lipoxygenase activity was found in both the protein bodies and on the surface of the oil bodies during the initial phase of seed germination. The association of lipoxygenase with oil bodies was temporally correlated with the appearance of phospholipase A and lipase activities on the surface of oil bodies. It is concluded that protein bodies not only serve as simple storage structures, but are also dynamic and multifunctional organelles directly involved in storage lipid mobilization during olive seed germination.

Electrophoretic profiling and immunocytochemical detection of pectins and arabinogalactan proteins in olive pollen during germination and pollen tube growth.

BACKGROUND AND AIMS: Cell wall pectins and arabinogalactan proteins (AGPs) are important for pollen tube growth. The aim of this work was to study the temporal and spatial dynamics of these compounds in olive pollen during germination. METHODS: Immunoblot profiling analyses combined with confocal and transmission electron microscopy immunocytochemical detection techniques were carried out using four anti-pectin (JIM7, JIM5, LM5 and LM6) and two anti-AGP (JIM13 and JIM14) monoclonal antibodies. KEY RESULTS: Pectin and AGP levels increased during olive pollen in vitro germination. (1 → 4)-ß-d-Galactans localized in the cytoplasm of the vegetative cell, the pollen wall and the apertural intine. After the pollen tube emerged, galactans localized in the pollen tube wall, particularly at the tip, and formed a collar-like structure around the germinative aperture. (1 → 5)-α-l-Arabinans were mainly present in the pollen tube cell wall, forming characteristic ring-shaped deposits at regular intervals in the sub-apical zone. As expected, the pollen tube wall was rich in highly esterified pectic compounds at the apex, while the cell wall mainly contained de-esterified pectins in the shank. The wall of the generative cell was specifically labelled with arabinans, highly methyl-esterified homogalacturonans and JIM13 epitopes. In addition, the extracellular material that coated the outer exine layer was rich in arabinans, de-esterified pectins and JIM13 epitopes. CONCLUSIONS: Pectins and AGPs are newly synthesized in the pollen tube during pollen germination. The synthesis and secretion of these compounds are temporally and spatially regulated. Galactans might provide mechanical stability to the pollen tube, reinforcing those regions that are particularly sensitive to tension stress (the pollen tube-pollen grain joint site) and mechanical damage (the tip). Arabinans and AGPs might be important in recognition and adhesion phenomena of the pollen tube and the stylar transmitting cells, as well as the egg and sperm cells.

Histochemical location of key enzyme activities involved in receptivity and self-incompatibility in the olive tree (Olea europaea L.).

Stigma-surface and style enzymes are important for pollen reception, selection and germination. This report deals with the histochemical location of the activity of four basic types of enzyme involved in these processes in the olive (Olea europaea L.). The detection of peroxidase, esterase and acid-phosphatase activities at the surface of the stigma provided evidence of early receptivity in olive pistils. The stigma maintained its receptivity until the arrival of pollen. Acid-phosphatase activity appeared in the style at the moment of anthesis and continued until the fertilization of the ovule. RNase activity was detected in the extracellular matrix of the styles of flowers just before pollination and became especially evident in pistils after self-pollination. This activity gradually decreased until it practically disappeared in more advanced stages. RNase activity was also detected in pollen tubes growing in pollinated pistils and appeared after in vitro germination in the presence of self-incompatible pistils. These findings suggest that RNases may well be involved in intraspecific pollen rejection in olive flowers. To the best of our knowledge this is the first time that evidence of enzyme activity in stigma receptivity and pollen selection has been described in this species.

Profiling and functional classification of esterases in olive (Olea europaea) pollen during germination.

BACKGROUND AND AIMS: A pollen grain contains a number of esterases, many of which are released upon contact with the stigma surface. However, the identity and function of most of these esterases remain unknown. In this work, esterases from olive pollen during its germination were identifided and functionally characterized. METHODS: The esterolytic capacity of olive (Olea europaea) pollen was examined using in vitro and in-gel enzymatic assays with different enzyme substrates. The functional analysis of pollen esterases was achieved by inhibition assays by using specific inhibitors. The cellular localization of esterase activities was performed using histochemical methods. KEY RESULTS: Olive pollen showed high levels of non-specific esterase activity, which remained steady after hydration and germination. Up to 20 esterolytic bands were identified on polyacrylamide gels. All the inhibitors decreased pollen germinability, but only diisopropyl fluorophosphate (DIFP) hampered pollen tube growth. Non-specific esterase activity is localized on the surface of oil bodies (OBs) and small vesicles, in the pollen intine and in the callose layer of the pollen tube wall. Acetylcholinesterase (AChE) activity was mostly observed in the apertures, exine and pollen coat, and attached to the pollen tube wall surface and to small cytoplasmic vesicles. CONCLUSIONS: In this work, for the first time a systematic functional characterization of esterase enzymes in pollen from a plant species with wet stigma has been carried out. Olive pollen esterases belong to four different functional groups: carboxylesterases, acetylesterases, AChEs and lipases. The cellular localization of esterase activity indicates that the intine is a putative storage site for esterolytic enzymes in olive pollen. Based on inhibition assays and cellular localization of enzymatic activities, it can be concluded that these enzymes are likely to be involved in pollen germination, and pollen tube growth and penetration of the stigma.

SNOM images of X-ray radiographs at nano-scale stored in a thin layer of lithium fluoride.

In this work, we report a method to observe soft X-ray radiographs at nanoscale of various kind of samples, biological and metallic, stored in a thin layer of lithium fluoride, employing scanning near-field optical microscopy with an optical resolution that reaches 50 nm. Lithium fluoride material works as a novel image detector for X-ray nano-radiographs, due to the fact that extreme ultraviolet radiation and soft X-rays efficiently produce stable point defects emitting optically stimulated visible luminescence in a thin surface layer. The bi-dimensional distribution of the so-created defects depends on the local nanostructure of the investigated sample.

Pla 1 1 and Ole e 1 pollen allergens share common epitopes and similar ultrastructural localization.

BACKGROUND: English plantain (Plantago lanceolata L.) and olive (Olea europaea L.) pollens are important causes of pollinosis in large areas of North America, Australia, and the Mediterranean basin. The major pollen allergens of both plants, Pla I 1 and Ole e 1, share 38.7% of their amino acid sequences. OBJECTIVE: To analyze putative cross-reactivity between these 2 proteins. METHODS: Several antibodies and patients' sera were used in immunoblot and immunocytochemistry experiments. RESULTS: Two anti-Pla I 1 antibodies were able to bind to 3 polypeptides from olive pollen protein extracts, which correspond to the 3 glycosylation isoforms of Ole e 1 (18-22 kDa) previously described. Moreover, Pla I 1 protein was found in the cytoplasm of both the vegetative and the generative cells of P lanceolata mature pollen. On olive pollen sections, these anti-Pla I 1 antibodies displayed significant labeling in the cytoplasm of the vegetative cell and in both the exine and the material adhering to this outer layer of the pollen wall. In addition, the anti-Ole e 1 antibody 10H1 was found to cross-react with proteins of similar masses (16-20 kDa) to Pla I 1 variants. In Plantago pollen sections, the 10H1 antibody recognized proteins located in the cytoplasm of both the vegetative and generative cells. Cross-reaction was confirmed using sera from patients allergic to either plant pollen. CONCLUSION: Both allergens share common epitopes, which can be cross-recognized by different antibodies and sera from different patients, although this antigenic similarity seems to have little clinical relevance.