27 research outputs found
Edible film based on candelilla wax to improve the shelf life and quality of avocado
In this study the effect of addition of ellagic acid (at three different concentrations) into candelilla wax matrix on shelf life and quality of whole avocados was studied. Control treatments were avocados coated with candelilla wax without ellagic acid and avocados without coating. The fruits were chosen for their maturity, size, free from infection and physical defects. All those samples were inoculated with a concentrated suspension of spores of Colletotrichum gloeosporioides, the main phytopathogenic fungus for avocados. Experiments were carried out completely divided into randomized groups. Changes in appearance, solids content, pH, aw, lightness (L* value) and weight loss were monitored during 6 weeks every 8 days. A sensory evaluation of avocados coated with the best edible film was also performed. Edibel films were able to reduce significantly the damage caused by C. gloeosporioides, reducing also significantly the change in appearance and weight loss in the fruits. Use of ellagic acid as part of the edible film has an important effect to improve the quality and shelf life of avocado. With this work we found that using this new protection system the negative effects of C. gloeosporioides can be successfully reduced
Genotoxic and Cytotoxic Studies of Beta-Sitosterol and Pteropodine in Mouse
Beta-sitosterol (BS) and pteropodine (PT) are constituents of various plants with pharmacological activities potentially useful to man. The chemicals themselves possess biomedical properties related to the modulation of the immune and the nervous systems, as well as to the inflammatory process. Therefore, safety evaluation of the compounds is necessary in regard to their probable beneficial use in human health. The present study evaluates their genotoxic and cytotoxic potential by determining the capacity of the compounds to induce sister chromatid exchanges (SCE), or to alter cellular proliferation kinetics (CPK) and the mitotic index (MI) in mouse bone marrow cells. Besides, it also determines their capacity to increase the rate of micronucleated polychromatic erythrocytes (MNPE) in peripheral mouse blood, and the relationship polychromatic erythrocytes/normochromatic erythrocytes (PE/NE) as an index of cytotoxicity. For the first assay, four doses of each compound were tested: 200, 400, 600, and 1000 mg/kg in case of BS, and 100, 200, 300, and 600 mg/kg for PT. The results in regard to both agents showed no SCE increase induced by any of the tested doses, as well as no alteration in the CPK, or in the MI. With respect to the second assay, the results obtained with the two agents were also negative for both the MNPE and the PE/NE index along the daily evaluation made for four days. In the present study, the highest tested dose corresponded to 80% of the LD(50) obtained for BS and to 78% in the case of PT. The results obtained establish that the studied agents have neither genotoxic nor cytotoxic effect on the model used, and therefore they encourage studies on their pharmacological properties
Perspectives on utilization of edible coatings and nano-laminate coatings for extension of postharvest storage of fruits and vegetables
It is known that in developing countries, a large quantity of fruit and vegetable losses results at postharvest and processing stages due to poor or scarce storage technology and mishandling during harvest. The use of new and innovative technologies for reducing postharvest losses is a requirement that has not been fully covered. The use of edible coatings (mainly based on biopolymers) as a postharvest technique for agricultural commodities has offered biodegradable alternatives in order to solve problems (e.g., microbiological growth) during produce storage. However, biopolymer-based coatings can present some disadvantages such as: poor mechanical properties (e.g., lipids) or poor water vapor barrier properties (e.g., polysaccharides), thus requiring the development of new alternatives to solve these drawbacks. Recently, nanotechnology has emerged as a promising tool in the food processing industry, providing new insights about postharvest technologies on produce storage. Nanotechnological approaches can contribute through the design of functional packing materials with lower amounts of bioactive ingredients, better gas and mechanical properties and with reduced impact on the sensorial qualities of the fruits and vegetables. This work reviews some of the main factors involved in postharvest losses and new technologies for extension of postharvest storage of fruits and vegetables, focused on perspective uses of edible coatings and nano-laminate coatings.María L. Flores-López thanks Mexican Science and Technology Council (CONACYT, Mexico) for PhD fellowship support (CONACYT Grant Number: 215499/310847). Miguel A. Cerqueira (SFRH/BPD/72753/2010) is recipient of a fellowship from the Fundação para a Ciência e Tecnologia (FCT, POPH-QREN and FSE Portugal). The authors also thank the FCT Strategic Project of UID/ BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the project ‘‘BioInd Biotechnology and Bioengineering for improved Industrial and AgroFood processes,’’ REF. NORTE-07-0124-FEDER-000028 Co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER. Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico – FUNCAP, CE Brazil (CI10080-00055.01.00/13)
Exomorfología y anatomía de órganos vegetativos aéreos en especies de Flourensia DC. (Asteraceae) con importancia fitoquímica
El género Flourensia DC. es americano y comprende 32 especies. Son arbustos resinosos utilizados en medicina popular; poseen un potencial valor económico, por lo que, en algunas especies representantes, se han caracterizado sus compuestos químicos y determinado algunos posibles usos. En el presente trabajo, se estudió la exomorfología y anatomía de órganos vegetativos de F. hirta S. F. Blake, F. leptopoda S. F. Blake, F. niederleinii S. F. Blake y F. tortuosa Griseb., especies endémicas del centro de Argentina. Se observó que todas son similares en cuanto a la anatomía de hoja y tallo. En cuanto al estudio de la epidermis foliar, se concluye que es posible diferenciar las especies teniendo en cuenta la frecuencia estomática y la presencia de tricomas. Finalmente, las diferencias más notables se encontraron en la exomorfología foliar ya que se observó una gran variación en cuanto a la forma de las hojas y tamaño de las láminas y pecíolos. Con respecto a las estructuras secretoras, se encontraron tricomas y conductos secretores esquizógenos en las hojas y los tallos de todas las especies, las cuales serían responsables de la producción y secreción de las resinas.The genus Flourensia DC. is American and comprises 32 species. They are resiniferous shrubs used in folk medicine. As they have potential economic value, its chemical compounds have been characterized and some possible uses identified. In this work, the exomorphology and anatomy of vegetative organs of F. hirta S. F. Blake, F. leptopoda S. F. Blake, F. niederleinii S. F. Blake and F. tortuosa Griseb., endemic species from central Argentina, have been studied. All species are similar in leaf and stem anatomy. Regarding the epidermis, it is possible to differentiate the species according to the stomatal frequency and the presence of trichomes. Finally, the most remarkable differences were found in leaf exomorphology, since there was a large variation in shape and size of blades and petioles. Concerning the secretory structures, trichomes and secretory ducts were found in the leaves and stems of all species, which would be responsible for the production and secretion of the resins
Morphological Description of the Early Events during the Invasion of Acanthamoeba castellanii Trophozoites in a Murine Model of Skin Irradiated under UV-B Light
Skin infections have been associated with Acanthamoeba, nevertheless the events during skin invasion and UV-B light effects on it are unknown. The early morphological events of Acanthamoeba castellanii skin invasion are shown in SKH-1 mice that were chronically UV-B light irradiated. Mice that developed skin lesions (group 1) were topical and intradermally inoculated with A. castellanii trophozoites and sacrificed 48 h or 18 days later. Mice that showed no skin lesions (group 2) were intradermally inoculated and sacrificed 24, 48 or 72 h later. Mice ventral areas were considered controls with and without trophozoites intradermally inoculated. Skin samples were processed by histological and immunohistochemistry techniques. In group 1, trophozoites were immunolocalized in dermal areas, hair cysts, sebaceous glands, and blood vessels, and collagen degradation was observed. One of these mice shown trophozoites in the spleen, liver, and brain. In group 2, few trophozoites nearby collagenolytic activity zones were observed. In control samples, nor histological damage and no trophozoites were observed. Adherence and collagenolytic activity by A. castellanii were corroborated in vitro. We can infer that UV-B light irradiated skin could favor A. castellanii invasiveness causing damage in sites as far away as the brain, confirming the invasive capacity and pathogenic potential of these amphizoic amoebae
Retinopathy of prematurity: Controversies in the usage of intraocular antiangiogenics [Retinopat�a del prematuro: Controversias en el uso de antiangiog�nicos intraoculares]
The increase in survival rates among preterm infants, characteristics of neonatal care for such infants and a lack of suitable programs for preventing, detecting and treating retinopathy of prematurity (ROP) are factors that have made this disease the main cause of preventable blindness among children in Mexico. The advent of antiangiogenic agents in cancer treatment and their off-label use with favorable results in the treatment of proliferative vessel disease of the retina among adult patients, as well as anecdotal reports in the literature and a series of cases showing serious methodological flaws, have prompted their use in the treatment of retinopathy of prematurity. Unfortunately, these agents used indiscriminately in our country have a systemic absorption and secondary effects on the preterm patient's body. There are no long-term monitoring studies that guarantee their safe use in this segment of the population. This article describes the situation in our country and warns of the risks posed by the use of this type of drug on the preterm infant population