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1.
Chem Biodivers ; 17(11): e2000707, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33025751

ABSTRACT

Lodoicea maldivica (J.F.Gmel.) Pers. (Arecaceae), 'Coco de Mer', is a palm, growing as endemic in the Seychelles islands. Its fruit weighs up to 20 kg and is characterized by a fleshy and fibrous envelope surrounding the nutlike portion. The present work combines a morpho-anatomical and a phytochemical analysis of the fruit exocarp and mesocarp. The exocarp is composed by a layer of palisade cells. The mesocarp is characterized by vascular bundles and by sclereids. In the aerenchyma, the internal zone of the mesocarp, cells aggregates were positive to phenols, while idioblasts were positive to terpenes. We performed a GC/MS analysis with a semi-quantitative relative amount calculation of the recorded compounds. The GC/MS essential oil profile revealed the dominance of acyclic sesquiterpenoids (53.95 %), followed by bicyclic sesquiterpenoids (31.69 %), monoterpenes (11.89 %) and monocyclic sesquiterpenoids (2.44 %). The terpenes detected in higher amounts, ß-caryophyllene and bicyclogermacrene, are known for activity against insect larvae, but have been proposed as antiviral candidates against SARS-CoV-2. The third compound in amount, aromadendrene, is active against bacteria and, again, known to possess insecticidal properties.


Subject(s)
Cocos/chemistry , Fruit/chemistry , Oils, Volatile/analysis , Anti-Bacterial Agents/analysis , Antiviral Agents/analysis , Azulenes/analysis , Betacoronavirus/drug effects , COVID-19 , Cocos/ultrastructure , Coronavirus Infections/drug therapy , Fruit/ultrastructure , Gas Chromatography-Mass Spectrometry , Humans , Insecticides/analysis , Monoterpenes/analysis , Pandemics , Pneumonia, Viral/drug therapy , SARS-CoV-2 , Sesquiterpenes/analysis
2.
Molecules ; 25(1)2020 Jan 06.
Article in English | MEDLINE | ID: mdl-31935819

ABSTRACT

In recent years, the biomimetic potential of lignified or partially lignified fruit pericarps has moved into focus. For the transfer of functional principles into biomimetic applications, a profound understanding of the structural composition of the role models is important. The aim of this study was to qualitatively analyze and visualize the functional morphology of the coconut endocarp on several hierarchical levels, and to use these findings for a more precise evaluation of the toughening mechanisms in the endocarp. Eight hierarchical levels of the ripe coconut fruit were identified using different imaging techniques, including light and scanning electron microscopy as well as micro-computer-tomography. These range from the organ level of the fruit (H0) to the molecular composition (H7) of the endocarp components. A special focus was laid on the hierarchical levels of the endocarp (H3-H6). This investigation confirmed that all hierarchical levels influence the crack development in different ways and thus contribute to the pronounced fracture toughness of the coconut endocarp. By providing relevant morphological parameters at each hierarchical level with the associated toughening mechanisms, this lays the basis for transferring those properties into biomimetic technical applications.


Subject(s)
Biomimetics , Cocos/cytology , Cocos/ultrastructure , Biomimetics/methods , Cocos/anatomy & histology , Mechanical Phenomena , Structure-Activity Relationship
3.
Food Chem ; 276: 129-139, 2019 Mar 15.
Article in English | MEDLINE | ID: mdl-30409575

ABSTRACT

This study investigated the structural characteristics of oil bodies from mature coconut (Cocos nucifera L.) fruit. The ultrastructure and the distribution of oil bodies in coconut endosperm were investigated using cryo-scanning electron microscopy. The interfacial characteristics of the oil bodies in suspensions isolated using two different protocols were studied using confocal laser scanning microscopy (CLSM), and the oleosins stabilizing the oil bodies were characterized using sodium dodecyl sulfate polyacrylamide electrophoresis. The oil bodies were found to be preferentially accumulated in endosperm tissues away from the inner endosperm and had a polydisperse size distribution, both intracellularly and in suspensions. The CLSM of oil bodies revealed uniform distribution of proteins and phospholipids at the interface along with glycolipids. Six different proteins were found to be associated with oil bodies some of which were disulfide-linked. This work provides new insights into the structure of coconut oil bodies and mechanisms for their stabilization.


Subject(s)
Cocos/ultrastructure , Endosperm/ultrastructure , Lipid Droplets/ultrastructure , Cocos/chemistry , Endosperm/chemistry , Lipid Droplets/chemistry , Microscopy, Confocal , Phospholipids/analysis , Plant Proteins/analysis
4.
Gac. méd. Caracas ; 121(2): 156-160, abr.-jun. 2013. ilus, graf
Article in Spanish | LILACS | ID: lil-718915

ABSTRACT

Se presenta el caso clínico de un paciente a quien la caída de un coco y el consecuente traumatismo sobre su cara. produjo una fractura del piso orbitario con atrapamiento muscular, diplopía no diagnosticada y confundida con un aneurisma cerebral. Se hacen consideraciones sobre este tipo de accidentes en playas arenosas donde abundan cocoteros. La comparación de su frecuencia con ataques de tiburón y acerca de cómo un artículo médico puede ser tergiversado por el autor y convertido en noticia de prensa como para obtener el Ig Premio Nobel de Medicina con base a "una investigación que no puede o no debe ser duplicada" logros que primero hacen reir y después pensar e intertan celebrar lo inusual, imaginativo y espolear el interés por la ciencia, la medicina y la tecnología


We present the clinical case of a patient who, after being hit the face by a falling coconut, with consequent trauma to his face, fractured his orbital floor with muscle entrapment and undiagnosed diplopia which was mistaken for a brain aneurysm. We make considerations about such accidents on sandy beaches where coconut trees abound, compare its frequency with shark attacks and discuss how a medical article can be misrepresented by its autor and become news in order to obtain the nomination for the Ig Nobel Prize for medicine based on "research that cannot or should not be duplicated; achievements that first make you laugh and then make you and try to celebrate the unusual, imaginative and spur interest in science, medicine and technology


Subject(s)
Aged , Diplopia/etiology , Enophthalmos/etiology , Facial Bones/injuries , Cocos/ultrastructure , Orbital Fractures/complications , Tomography/methods
5.
Bioresour Technol ; 99(17): 8476-84, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18558484

ABSTRACT

Plant fibres are capacious for sorption of metal ions, and can be used in water cleaning. Knowledge about the sorption will help in selection of the fibre and optimisation of its chemical modification, if any. The aim of this paper is to investigate the connection, if any, between the distribution of lignin and pectin and the loading of Pb and Zn on coir (mesocarp fibres from Cocos nucifera L.). The coir consisted mainly of xylem and a fibre sheath. The lignin was evenly distributed in the cell walls of the fibre sheath, but in the xylem, there was no detectable content in the compound middle lamella, and a smaller content of lignin in the secondary walls than in the walls of the fibre sheath. The only detectable content of pectin in the fibre sheath walls was in the middle lamella, cell corners and extracellular matrix, while in the xylem, the pectin was almost evenly distributed in the wall, with a higher concentration in the middle lamella and cell corners. All cell walls facing the lacuna had a high content of pectin. The metal ions were mainly loaded on the xylem and cell walls facing the lacuna, maybe with an additional trend to be loaded on the large fibres. Lead was distributed on and across the whole secondary wall. Zinc was loaded on the secondary walls, but there was no information about the distribution across the wall. If there is a simple correlation between the loading of metal ions and the distribution of lignin or pectin, these investigations point at no correlation with lignin and a positive correlation with pectin. It has to be stressed that these conclusions are made on limited material and are therefore preliminary in nature.


Subject(s)
Cocos/metabolism , Lead/isolation & purification , Lignin/metabolism , Pectins/metabolism , Zinc/isolation & purification , Adsorption , Biodegradation, Environmental , Cocos/cytology , Cocos/ultrastructure , Fluorescence , Microscopy, Electron, Scanning , X-Rays
6.
J Hazard Mater ; 154(1-3): 337-46, 2008 Jun 15.
Article in English | MEDLINE | ID: mdl-18035483

ABSTRACT

Adsorption isotherm and kinetics of methylene blue on activated carbon prepared from coconut husk were determined from batch tests. The effects of contact time (1-30 h), initial dye concentration (50-500 mg/l) and solution temperature (30-50 degrees C) were investigated. Equilibrium data were fitted to Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models. The equilibrium data were best represented by Langmuir isotherm model, showing maximum monolayer adsorption capacity of 434.78 mg/g. The kinetic data were fitted to pseudo-first-order, pseudo-second-order and intraparticle diffusion models, and was found to follow closely the pseudo-second-order kinetic model. Thermodynamic parameters such as standard enthalpy (DeltaH degrees), standard entropy (DeltaS degrees) and standard free energy (DeltaG degrees) were evaluated. The adsorption interaction was found to be exothermic in nature. Coconut husk-based activated carbon was shown to be a promising adsorbent for removal of methylene blue from aqueous solutions.


Subject(s)
Carbon/chemistry , Cocos , Coloring Agents/chemistry , Methylene Blue/chemistry , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/chemistry , Water Purification/methods , Adsorption , Cocos/ultrastructure , Diffusion , Kinetics , Microscopy, Electron, Scanning , Porosity , Surface Properties , Thermodynamics
7.
Bioprocess Biosyst Eng ; 28(3): 165-73, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16220267

ABSTRACT

Coir fiber belongs to the group of hard structural fibers obtained from coconut husk. As lignin is the main constituent of coir responsible for its stiffness, microbes that selectively remove lignin without loss of appreciable amounts of cellulose are extremely attractive in biosoftening. Five isolated strains were compared with known strains of bacteria and fungi. The raw fiber treated with Pseudomonas putida and Phanerocheate chrysosporium produced better softened fiber at 30+/-2 degrees C and neutral pH. FeSO4 and humic acid were found to be the best inducers for P. chrysosporium and P. putida, respectively, while sucrose and dextrose were the best C-sources for both. Biosoftening of unretted coir fibers was more advantageous than the retted fibers. Unlike the weak chemically softened fiber, microbial treatment produced soft, whiter fibers having better tensile strength and elongation (44.6-44.8%) properties. Scanning electron microscopy photos showed the mycelia penetrating the pores of the fiber, removing the tylose plug and degrading lignin.


Subject(s)
Cocos/chemistry , Nuts/chemistry , Phanerochaete/growth & development , Pseudomonas putida/growth & development , Cocos/ultrastructure , Nuts/ultrastructure , Phanerochaete/ultrastructure , Pseudomonas putida/ultrastructure
8.
Micron ; 36(2): 169-75, 2005.
Article in English | MEDLINE | ID: mdl-15629648

ABSTRACT

We have evaluated the parasitism of the red scale insect of the date palm (Phoenicococcus marlatti) by entomopathogenic fungi, using light microscopy (LM), scanning electron microscopy (SEM) and low temperature scanning electron microscopy (LTSEM). Beauveria bassiana, Lecanicillium dimorphum and Lecanicillium cf. psalliotae, were inoculated directly on the scale insects or on insect infested plant material. We found that L. dimorphum and L. cf. psalliotae developed on plant material and on scale insects, making infection structures. B. bassiana was a bad colonizer of date palm leaves (Phoenix dactylifera L.) and did not parasite the scale insects.


Subject(s)
Cocos/microbiology , Cocos/ultrastructure , Fungi/pathogenicity , Fungi/cytology , Fungi/ultrastructure , Microscopy, Electron, Scanning/methods , Plant Leaves/microbiology , Plant Leaves/ultrastructure
9.
Pflugers Arch ; 444(1-2): 286-90, 2002 May.
Article in English | MEDLINE | ID: mdl-11976942

ABSTRACT

Nuclear pore complexes (NPCs) are important nanochannels for the control of gene activity and expression. Most of our knowledge of NPC function has been derived from isolated nuclei and permeabilized cells in cell lysates/extracts. Since recent patch-clamp work has challenged the dogma that NPCs are freely permeable to small particles, a preparation of isolated living nuclei in their native liquid environment was sought and found: the syncytial nuclei in the water of the coconut Cocos nucifera. These nuclei have all properties of NPC-mediated macromolecular transport (MMT) and express foreign green fluorescent protein (GFP) plasmids. They display chromatin movement, are created by particle aggregation or by division, can grow by throwing filaments to catch material, etc. This study shows, for the first time, that living NPCs engaged in MMT do not transport physiological ions - a phenomenon that explains observations of nucleocytoplasmic ion gradients. Since coconuts are inexpensive (less than US$1/nut per litre), this robust preparation may contribute to our understanding of NPCs and cell nucleus and to the development of biotechnologies for the production of DNA, RNA and proteins.


Subject(s)
Cell Nucleus/physiology , Cocos/metabolism , Ion Channels/physiology , Cell Nucleus/ultrastructure , Chromatin/metabolism , Chromatin/ultrastructure , Cocos/ultrastructure , DNA/biosynthesis , DNA/genetics , Electrophysiology , Green Fluorescent Proteins , Ion Channels/ultrastructure , Luminescent Proteins/biosynthesis , Luminescent Proteins/genetics , Patch-Clamp Techniques , Permeability , Plasmids , RNA/biosynthesis
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