Development of a new method to prepare nano-/microparticles loaded with extracts of azadirachta indica, their characterization and use in controlling plutella xylostella

Biodegradable nanoparticles have been widely explored as carriers for controlled delivery of therapeutic molecules; however, studies describing the development of nanoparticles as carriers for biopesticide products are few. In this work, a new method to prepare nanoparticles loaded with neem (Azadirachta indica) extracts is presented. In this study, nanoparticles were formulated as colloidal suspension and (spray-dried) powder and characterized by evaluating pH, particle size, zeta potential, morphology, absolute recovery, and entrapment efficiency. A high-performance liquid chromatography method was used for nanoparticle characterization. The best formulations presented absolute recovery and entrapment efficiencies of approximately 100% and a release profile based on swelling and relaxation of the polymer or polymer erosion. The biological data of the formulated products against Plutella xylostella showed 100% larval mortality. The nanoparticle information improved the stability of neem products against ultraviolet radiation and increased their dispersion in the aqueous phase. © 2013 American Chemical Society.

Caracterização química e físico-química e estudos preliminares de planejamento da formulação fitoterápica semi-sólida contendo tintura de Calendula officinalis L.

A fitoterapia constitui uma forma de terapia medicinal que vem crescendo visivelmente ao longo dos anos, no entanto, apesar da extensa utilização dos fitoterápicos, a qualidade destes medicamentos muitas vezes é deficiente e questionável. Dentre as plantas medicinais mais empregadas como fitoterápicos, temos a Calendula officinalis L.(Asteraceae), utilizada pelos seus efeitos antiinflamatórios, antisépticos e cicatrizantes. Sendo assim, o presente estudo objetivou aprimorar e consolidar o emprego de metodologias de tecnologia farmacêutica na área de desenvolvimento de fitoterápicos, por meio da realização de estudos preliminares do planejamento/pré-formulação de uma formulação fitoterápica semi-sólida contendo tintura de C. officinalis L., visando o controle de qualidade das etapas do seu desenvolvimento. Na caracterização física e físico-química do pó e da tintura de calêndula foi possível obter especificações farmacognósticas condizentes com as da literatura, além de constatar a identidade do material vegetal através da detecção do marcador químico rutina por CCD. Por meio da validação do método, que apresentou parâmetros recomendados pela legislação vigente, foram determinados 463 μg/mL de rutina na tintura. Os espectros obtidos na região do infravermelho (IV) mostraram bandas características da rutina no extrato liofilizado, além de demonstrar a permanência dessas bandas após sua mistura com os excipientes da formulação. As técnicas termoanalíticas confirmaram a compatibilidade entre os excipientes e o extrato liofilizado de calêndula. Na avaliação da estabilidade preliminar do gel, a formulação permaneceu estável durante a realização dos ciclos em estufa (45 2 0C) e temperatura ambiente (25 2 0C). No estudo preliminar da permeação, o gel apresentou tendência para favorecer a permeação dos flavonóides totais expresso em rutina para a fase receptora. Estes resultados demonstram a importância do emprego de protocolos de controle de qualidade das matérias primas vegetais, além do estabelecimento de metodologias tecnológicas para a produção de fitoterápicos.

Foraminifera, thecamoebians and palynomorphs as hydrodynamic indicators in Araguari Estuary, Amazonian Coast, Amapá State - Brazil

O regime de macromaré e a pororoca controlam a dinâmica estuarina do Araguari, na qual é muito diferente dos modelos tradicionais dos estuários sob este regime de maré. Objetivando estabelecer zonas estuarinas no Araguari com base em assembléias de foraminíferos, tecamebas, palinomorfos e parâmetros físico-químicos, foram estabelecidas dezesseis estações amostrais ao longo do estuário. A turbidez e a temperatura foram os parâmetros ambientais que permitiram determinar gradiente estuarino. Dezoito espécies de foraminíferos, dez espécies de tecamebas e quatorze espécies de palinomorfos foram identificadas. A análise de agrupamento em modo-R mostrou a existência de assembléias de foraminíferos e quatro de palinomorfos. A análise em CCA demonstrou que a turbidez e a matéria orgânica como os parâmetros de maior influência na distribuição dos foraminíferos tecamebas no Araguari. A análise de agrupamento em Modo-Q usando todos os dados formou quarto grupos de estações que sugerem a existência de três zonas estuarinas: Zona I - composta por tecamebas e palinomorfos continentais; Zona II - compostas por foraminíferos de manguezal, acritacos e todas as assembléias de palinomorfos; e Zona III - composta por foraminíferos de manguezal e estuarinos e por todas as assembléias de palinomorfos.

Effect of Cultivation Practices on the beta-Glucan Content of Agaricus subrufescens Basidiocarps

Processo FAPESP: 12/15101-4

Broad-scale spatial patterns of canopy cover and pond morphology affect the structure of a Neotropical amphibian metacommunity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Home Cooking and Phenolics: Effect of Thermal Treatment and Addition of Extra Virgin Olive Oil on the Phenolic Profile of Tomato Sauces

Tomato products are a key component of the Mediterranean diet, which is strongly related to a reduced risk of cardiovascular events. The effect of cooking time (15, 30, 45, and 60 min) and the addition of extra virgin olive oil (5 and 10%) on the phenolic content of tomato sauces was monitored using liquid chromatography coupled to tandem mass spectrometry. Concentration of phenolics in the tomato sauces decreased during the cooking process, with the exception of caffeic acid and tyrosol. The main degradation observed was the oxidation of quercetin, since the hydroxy-function at the C-ring of this flavonoid is not blocked by a sugar moiety, unlike rutin. Higher levels of virgin olive oil in tomato sauce seemed to enhance the extraction of phenolic compounds from the tomato, leading to higher phenolic contents in the sauces. Thus, the food matrix containing the phenolic compounds plays a crucial role in determining their accessibility.

"Will It Rain?" Activities Investigating Aerosol Hygroscopicity and Deliquescence

Climate change and its consequences seem to be increasingly evident in our daily lives. However, is it possible for students to identify a relationship between these large-scale events and the chemistry taught in the classroom? The aim of the present work is to demonstrate that chemistry can assist in elucidating important environmental issues. Simple experiments are used to demonstrate the mechanism of cloud formation, as well as the influence of anthropogenic and natural emissions on the precipitation process. The experiments presented show the way in which particles of soluble salts commonly found in the environment can absorb water in the atmosphere and influence cloud formation.

Solid Lipid Nanoparticles Co-loaded with Simazine and Atrazine: Preparation, Characterization, and Evaluation of Herbicidal Activity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Synthesis, Characterization, and Antifungal Activities of Amphiphilic Derivatives of Diethylaminoethyl Chitosan against Aspergillus flavus

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Polyphenol oxidase from sweet potato: Purification and properties

Polyphenol oxidase (PPO, EC 1.14.18.1) extracted from sweet potato root [Ipomoea batatas (L.) Lam.] was purified 189-fold by precipitation with ammonium sulfate and elution from columns of Sephadex G-25, DEAE-cellulose, and Sephadex G-100. Polyacrylamide gel electrophoresis of the purified preparation revealed that PPO was highly purified by the procedure adopted. The purified enzyme had an estimated molecular weight of 96 000 and Km values of 26, 8, 5, and 96 mM for 4-methylcatechol, chlorogenic acid, caffeic acid, and catechol, respectively. The optimum pH varies from about 4.0 to 6.5, depending on the substrate. PPO activity was inhibited by p-coumaric and cinnamic acids, sodium metabisulfite, dithioerythritol, ascorbic acid, L-lysine, D-phenylalanine, L-methionine, glycine, L-isoleucine, and L-glutamine. Heat inactivation between 60 and 80 °C was biphasic. Sucrose, (NH4)2SO4, NaCl, and KCl appeared to be protective agents of sweet potato PPO against thermal denaturation. © 1992 American Chemical Society.

Aging of intrauterine tissues in spontaneous preterm birth and preterm premature rupture of the membranes: a systematic review of the literature

Many adverse pregnancy outcomes (APOs), including spontaneous preterm birth (PTB), are associated with placental dysfunction. Recent clinical and experimental evidences suggest that premature aging of the placenta may be involved in these events. Although placental aging is a well-known concept, the mechanisms of aging during normal pregnancy and premature aging in APOs are still unclear. This review was conducted to assess the knowledge on placental aging related biochemical changes leading to placental dysfunction in PTB and/or preterm premature rupture of membranes (pPROM). We performed a systematic review of studies published over the last 50 years in two electronic databases (Pubmed and Embase) on placental aging and PTB or pPROM. The search yielded 554 citations, 30 relevant studies were selected for full-text review and three were included in the review. Only one study reported oxidative stress-related aging and degenerative changes in human placental membranes and telomere length reduction in fetal cells as part of PTB and/or pPROM mechanisms. Similarly, two animal studies reported findings of decidual senescence and referred to PTB mechanisms. Placental and fetal membrane oxidative damage and telomere reduction are linked to premature aging in PTB and pPROM but the risk factors and biomolecular pathways causing this phenomenon are not established in the literature. However, no biomarkers or clinical indicators of premature aging as a pathology of PTB and pPROM have been reported. We document major knowledge gaps and propose several areas for future research to improve our understanding of premature aging linked to placental dysfunction.

Rapid determination of 12 antibiotics and caffeine in sewage and bioreactor effluent by online column-switching liquid chromatography/tandem mass spectrometry

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Albumin-induced circular dichroism in Congo red: applications for studies of amyloid-like fibril aggregates and binding sites

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Inhibitory effect of gallic acid and its esters on 2,2'-azobis(2-amidinopropane)hodrpchloride (AAPH)-induced hemolysis and depletion of intracellular glutathione in erythrocytes

The protective effect of gallic acid and its esters, methyl, propyl, and lauryl gallate, against 2,2'-azobis(2-amidinopropane)hydrochloride (AAPH)-induced hemolysis and depletion of intracellular glutathione (GSH) in erythrocytes was studied. The inhibition of hemolysis was dose-dependent, and the esters were significantly more effective than gallic acid. Gallic acid and its esters were compared with regard to their reactivity to free radicals, using the DPPH and AAPH/pyranine free-cell assays, and no significant difference was obtained. Gallic acid and its esters not only failed to inhibit the depletion of intracellular GSH in erythrocytes induced by AAPH but exacerbated it. Similarly, the oxidation of GSH by AAPH or horseradish peroxidase/H(2)O(2) in cell-free systems was exacerbated by gallic acid or gallates. This property could be involved in the recent findings on pro-apoptotic and pro-oxidant activities of gallates in tumor cells. We provide evidence that lipophilicity and not only radical scavenger potency is an important factor regarding the efficiency of antihemolytic substances.

Documentação química de espécies do gênero Casearia (Salicaceae) de importância ecológica, econômica e medicinal

The Casearia genus (Salicaceae) is well known because of the medicinal use of its species. Among them, a noteworthy one is the C. sylvestris specie because it already has studies concerning its antiproliferative and/or cytotoxic activity in tumor cells. Furthermore, this specie is popularly used against snake bites, in gastric ulcers treatment and as anti-inflammatory. As well as this, there are other species from this same genus which have been poorly studied, such as the following species: C. decandra, C. grandiflora, C. javitensis, C. arborea, C. lasiophylla and C. ulmifolia. However, several biological activities have been reported for them. In this context, the aim of this project, besides of contributing to the Casearia genus studies, is to study those six species through the analysis and documentation of their leaves' chemical composition (aqueous, ethanolic and hexanic extracts), using analytical separation techniques coupled with spectroscopic techniques, such as UHPLC-DAD, GC-MS and NMR 1H, which will assist the identification of new secondary metabolites in this genus. Moreover, another goal of this present work is aiming the bioprospection of substances with medicinal and economical potential and finally promote the systematic study of some biological activities, such as antimicrobial and cytotoxicity bioassays. A wide variety of metabolites was identified in those three types of extracts, being most of them detected for the first time in Casearia genus, highlighting C. lasiophylla and C. decandra for featuring antimicrobial activity against Staphylococcus aureus.