Preparation and characterization of liposomes loaded with silver nanoparticles obtained by green synthesis

The objective of this work was to develop and characterize liposomes loaded with silver nanoparticles (LAgNPs) to show improvement in stability characteristics. AgNPs were prepared by the green synthesis method with Aloe vera gel extract and exposure to sunlight. Liposomes were prepared by the modified reverse phase method. Particle size, polydispersity index, zeta potential, as well as the scanning electron microscopy (SEM) morphological aspects of AgNPs and LAgNPs were evaluated. In addition, was used flame atomic absorption spectroscopy to determine the amount of AgNP that was encapsulated in liposomes. The AgNPs presented as amorphous and polydisperse structures, with a mean diameter of 278.46 nm and zeta potential of -18.3 mV. LAgNPs had a mean diameter between 321 and 373 nm, the polydispersity index close to 0.2 and a zeta potential around -40 mV, which indicates greater stability to the AgNPs. The images obtained by SEM show semicircular structures for AgNPs and well-defined spherical shape for LAgNPs. The percentage of encapsulation was between 51.81 to 58.83%. These results showed that LAgNPs were obtained with adequate physicochemical characteristics as a release system.

Biologia reprodutiva e ausência de frutificação de Aloe saponaria (Aiton) Haw. (Xanthorrhoeaceae) fora do local de origem / Reproductive biology and absence of fruiting of Aloe saponaria (Aiton) Haw. (Xanthorrhoeaceae) outside its place of origin

RESUMO O gênero Aloe, originário principalmente da África, tem atualmente uma ampla distribuição no mundo. No entanto, são poucas as regiões que têm realizado estudos quanto ao sistema reprodutivo. O objetivo do presente trabalho foi analisar as características e o comportamento reprodutivo de Aloe saponaria em Florianópolis, Santa Catarina. Foram conduzidos estudos sobre sua morfologia e biologia floral, visitantes florais e sistema reprodutivo. Esta espécie apresentou uma inflorescência por planta, com um comprimento de 105 ± 0,1 cm e 267 ± 92,7 flores. A razão pólen/óvulo sugere que a espécie é xenogâmica. O volume e concentração de sólidos solúveis totais do néctar potencial foi 16,6 ± 6,3 μL e 22 ± 2,4 °Brix respectivamente. O néctar instantâneo não apresentou diferenças significativas nos períodos avaliados (9:00h e 15:00h) e o estigma permaneceu receptivo até o segundo dia após a antese. Foram coletados 110 insetos visitantes florais, dos quais 61,8% foram indivíduos de Trigona spinipes. Entretanto, nos testes de polinização não foi observada frutificação efetiva, indicando que a propagação vegetativa é o principal tipo de reprodução usado nessa população. Isto pode estar relacionado a um mecanismo de autoincompatibilidade esporofítica, a anormalidades cromossômicas durante a formação do pólen, as condições climáticas, e a escassa variabilidade genética no local de estudo.

ABSTRACT The Aloe genus, originating mainly from Africa, currently has a wide distribution in the world. However, in few regions studies about the reproductive system have been carried on. The aim e of this study was to analyze the characteristics and reproductive performance of the Aloesaponaria in Florianópolis, Santa Catarina. The morphology, floral biology, flower visitors and the reproductive system were determined. The plants presented an inflorescence per plant, with 105 ± 0,1 cm in length and 267 ± 92.7 flowers. The pollen/ovule ratio suggested that the species is xenogamic. The volume and concentration of total soluble solids in the potential nectar were 16.6 ± 6.3 μL and 22 ± 2.4°Brix, respectively. The instant nectar showed no significant differences between the evaluated periods (9:00h and 15:00h) and the stigma remained receptive until the second day the after anthesis. 110 insects were collected, from which 61.8% were from theTrigona spinipesspecies. However, in the pollination tests the fruit set was not observation, indicating that vegetative propagation is the main type of reproduction used by this population. This may be related to a mechanism of sporophytic self-incompatibility, to chromosomal abnormalities during the formation of pollen, to weather conditions, and to the low genetic variability at the study site.

Current Perspectives on Use of Aloe vera in Dentistry.

Introduction: Aloe vera is known from centuries as a medicinal plant. It’s a wonder plant with a lot of health benefits and hence often been called the 'natural healer'. It is a tropical plant that flourishes in warm and dry climate and looks like a cactus with fleshy thorny leaves. There are around 400 species of Aloe, but it is the Aloe barbadensis Miller (Aloe vera or "true aloe") plant which has been used most (found mainly in Asia, Africa and other tropical areas) because of its medicinal uses like moisturizing, anti-inflammatory, antioxidant, anticancer, antibacterial, antiviral and antifungal properties. Medicinal Uses: Aloe vera has its uses in various systemic conditions like skin disorders (e.g. psoriasis), arthritis, asthma, digestive and bowel disorders, diabetes and lowering lipid levels in hyper-lipidemic patients. It has also be used as a detoxifying agent, for topical application of first and second degree burns, as a immune enhancer, in Alzheimer’s disease and in various cosmetic, medical and dental products. Dental Uses: This wonder plant has also been used in dentistry for its beneficial properties in various conditions like lichen planus, apthous stomatitis, oral submucous fibrosis, pulpotomy of primary teeth, prevention of dry sockets, obturation of primary teeth, disinfection of irrigation units, bleeding and painful gums, disinfection of gutta percha cones, burning mouth syndrome and in radiated head and neck cancer patients. The purpose of this article is to highlight the role of A. barbadensis in various branches of dentistry and its potential future role. Conclusion: Aloe vera indeed has a definitive useful role in dentistry. However, future researches should be aimed to determine its method of preparation, optimal concentration, time of application and effects on the oral cavity.

Efecto agudo del aloe vera linneo y ciclanthera pedata shrad en ratas diabéticas / Acute hypoglycemic effect of aloe vera linneo and cyclanthera pedata shrad on diabetic rats

Se compara el efecto hipoglicemiante y la toxicidad del gel gel Aloe vera linneo y del extracto de Ciclanthera pedata schrad en ratas hiperglicémicas y ratones normales utilizando un estudio randomizado, cohorte de inicio de tipo longitudinal, con seguimiento de 48 horas. Se utilizaron 36 ratas albinas "Wistar". Se dividió en dos grupos de 18 ratas c/u A y B, que a su vez se subdividieron en 3 grupos de 6 ratas c/u. Al grupo A se le administró 125 mg/Kg de peso de aloxano y al grupo B 100 mg/Kg de peso via subcutanea. Posteriormente se dio a los grupos A1 y B1 aloe 10 mg/Kg, A2 y B2 caihua 10 mg/Kg; por último A3 y B3 reciben aloe (4 mg.Kg) y Caihua (6 mg/Kg) juntos. Todos los extractos se dieron por vía intraperitoneal (IP). Además, se utilizó 24 ratones blancos normales para la prueba de Dosis Letal 50 (DL50) agudo, recibieron via IP la dosis de 1, 10, 100 y 1000 mg/Kg de peso de aloe, caihua y ambos. Para la DL50 no se reportó ninguna muerte dentro de las 72 horas siguientes. En los animales del grupo A no se observó efecto hipoglicemiante de los extractos. En los 3 subgrupos B se observó una disminución de los niveles de glucosa con relación a la glicemia basal; la estadística fue estadística significativa en los subgrupos B1 y B3 (p<0,05). El grupo B3 mostró efecto a partir de la 3ra hora, mientras los otros grupos lo conseguian a la 5ta o 7ma hora. Se demuestra la carencia de toxicidad del gel del Aloe vera linneo y el extracto de Ciclanthera pedata schrad a dosis aguda; también sus efectos hipoglicemiantes con mejor resultado al administrarlos juntos.