Chitosan as flocculant agent for clarification of stevia extract

Stevia is used as a sweetener due to its low calorific value and its taste, which is very similar to that of sucrose. After extraction from dried leaves, stevia extract is dark in colour, and therefore needs to be whitened to increase acceptance by consumers. In this study we tested chitosan, a cationic polyelectrolyte, as flocculant agent for the whitening of the Stevia extract. Positive charges of chitosan can interact electrostatically with a counter-ion, sodium tripolyphosphate (TPP), and then chitosan precipitates. A factorial design was used to study the whitening process, in which Glycosides Removal, Colour Removal, Turbidity Removal and Soluble Solids Removal were evaluated. The studied factors were Chitosan Mass and pH of the TPP solution. The results showed that chitosan is a good flocculant agent, being able to flocculate both the glycosides and the pigments that make the extract coloured.UNIOESTE Centro de Engenharias e Ciências ExatasUNIFESP Centro de Ciências Exatas e da TerraUNIFESP, Centro de Ciências Exatas e da TerraSciEL

Effects of glyphosate on hepatic tissue evaluating melanomacrophages and erythrocytes responses in neotropical anuran <i>Leptodactylus latinasus</i>

Glyphosate (GLY) is the most used herbicide worldwide and its effects on anurans are well known. Pollutants can cause physiological and morphological effects. Therefore, this study evaluated the effects of GLY on hepatic melanomacrophages as a response to environmental stressors. Three treatments were exposed to different concentrations of pure GLY (100, 1000, and 10,000 μg g⁻¹, respectively), and there was also a control group. After the experimental time, liver and blood were analyzed. Melanomacrophages (MMCs) were located between the hepatocyte cordons, close to sinusoids. GLY increased the melanin area in MMCs of Leptodactylus latinasus exposed since lowest concentration until highest concentration. GLY also changed the occurrence of hepatic catabolism pigments into melanomacrophages and erythrocyte nuclear abnormalities; therefore, it can interfere with the hepatic metabolism. In conclusion, GLY promotes alterations in the hepatic tissue and erythrocyte nuclear abnormalities. Furthermore, MMCs may be useful as morphological responses of GLY effects.Facultad de Ciencias ExactasCentro de Investigaciones del Medioambient

β-cyclodextrin/isopentyl caffeate inclusion complex: synthesis, characterization and antileishmanial activity

Isopentyl caffeate (ICaf) is a bioactive ester widely distributed in nature. Our patented work has shown promising results of this molecule against Leishmania. However, ICaf shows poor solubility, which limits its usage in clinical settings. In this work, we have proposed the development of an inclusion complex of ICaf in -cyclodextrin (-CD), with the aim to improve the drug solubility, and thus, its bioavailability. The inclusion complex (ICaf:-CD) was developed applying three distinct methods, i.e., physical mixture (PM), kneading (KN) or co-evaporation (CO) in different molar proportions (0.25:1, 1:1 and 2:1). Characterization of the complexes was carried out by thermal analysis, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and molecular docking. The ICaf:-CD complex in a molar ratio of 1:1 obtained by CO showed the best complexation and, therefore, was selected for further analysis. Solubility assay showed a marked improvement in the ICaf:-CD (CO, 1:1) solubility profile when compared to the pure ICaf compound. Cell proliferation assay using ICaf:-CD complex showed an IC50 of 3.8 and 2.7 µg/mL against L. amazonesis and L. chagasi promastigotes, respectively. These results demonstrate the great potential of the inclusion complex to improve the treatment options for visceral and cutaneous leishmaniases.This research was funded by Banco do Nordeste (grant FUNDECI/2016.0015), Coordenação Aperfeiçoamento de Pessoal de Nivel Superior (CAPES) and Fundação de Ámparo à Pesquisa do Estado de Sergipe (FAPITEC) (PROCESSO: 88887.159533/2017-00 extração, encapsulação e caracterização de bioativos para o interesse biotecnologico). Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq 301964/2019-0 Chamada 06/2019, and Chamada CNPq nº 01/2019) and from the Portuguese Science and Technology Foundation (FCT) project UIDB/04469/2020 (strategic fund).info:eu-repo/semantics/publishedVersio

Morfometria testicular durante o ciclo reprodutivo de Dendropsophus minutus (Peters) (Anura, Hylidae)

Este estudo descreve o ciclo reprodutivo de machos de Dendropsophus minutus (Peters, 1872) com base na análise da morfometria testicular e a correlação com parâmetros climáticos. Cinqüenta indivíduos foram coletados em São José do Rio Preto, São Paulo. Após as análises macroscópicas, os testículos foram encaminhados à rotina histológica, fixados com Bouin e incluídos em historesina. Cortes de 2 µm foram corados com azul de toluidina 1% e observados ao microscópio. Testículos de D. minutus são órgãos pequenos (comprimento 1,90 &plusmn; 0,13 mm), esbranquiçados, com forma oval e encontrados na cavidade abdominal. Estão localizados na extremidade cranial dos rins e apresentam assimetria quanto a sua posição. Estatisticamente não há variação intra-individual no comprimento e no peso dos testículos, bem como na área e diâmetro dos lóculos seminíferos. Quanto à histologia testicular, foi possível identificar ao longo do ano nos lóculos seminíferos, todos os tipos celulares da linhagem espermatogênica, caracterizando uma gametogênese contínua, corroborada por fatores ecológicos e comportamentais. Informações sobre a morfometria testicular e ciclo reprodutivo tem importante valor biológico para anuros de regiões neotropicais.This study describes the male reproductive cycle of Dendropsophus minutus (Peters, 1872) based on testicular morphometric analysis, related to climatic conditions. Fifty individuals where collected in São José do Rio Preto, São Paulo. After macroscopic analysis, the testes were submitted to histological routine, fixed with Bouin, embedded in historesin. Sections of 2 µm were stained with 1% toluidine blue and observed to the microscope. The testes of D. minutus are small organs (length 1.90 &plusmn; 0.13 mm), whitish, oviform and found in the abdominal cavity. They are located in the cranial extremity of the kidneys and present asymmetry as far as position. According to statistical analyses, there is no intra-individual variation in length and weight of the testes, as well as in the area and diameter of the seminiferous locules. Concerning the testicular histology, it was possible to identify, throughout the year, in seminiferous locules, all the cellular types from the spermatogenic lineage, characterizing a continuous gametogenesis, corroborated by ecological and behavioral factors. Information about testicular morphometry and reproductive cycle has important biological value for anurans in the neotropics.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Histological characterization of cellular types during Scinax fuscovarius oogenesis (Lutz) (Anura, Hylidae)

This paper describes morphological characteristics of the ovarian germinative cells of the Scinax fuscovarius (Lutz, 1925). The ovary is organized in primordial germinative cells (oogonia) and follicular structures (ovarian follicle) - oocytes surrounded by follicular cells. Oogonia: their nests are peripherically localized, containing cells with large and oval nucleus. Oocytes I: basophilic cytoplasm; the spherical nucleus presents few nucleoli, one or two; the follicular cells (one tenuous layer) surround these previtellogenic cells. Oocytes II: the cell is larger and the cytoplasm becomes more basophilic; the nucleus presents few nucleoli and contains many chromosomes in the periphery (beginning the perinucleolar stage). Oocytes III: the cytoplasm acquires an intense acidophilia; the peripherical region of cytoplasm is filled with yolk and the internal region has no yolk at all; pigment synthesis begins; the follicular envelope presents three tenuous layers: an inner acellular (vitelline envelope) and two cellular layers (follicle cells). Oocytes IV: a characteristic of this stage is the differentiation between the animal and the vegetal poles; the nucleus in the animal hemisphere and the pigments give the oocyte a color dark brown; the vitellogenesis is intense and the yolk occupies the whole cytoplasm.<br>O estudo apresenta algumas características histológicas das células germinativas ovarianas de Scinax fuscovarius (Lutz, 1925) após análise com colorações pelo H/E e Tricrômico de Mallory. O ovário apresenta as células germinativas primordiais, as ovogônias, as quais passam por uma citodiferenciação e, juntamente com células somáticas associadas, constitui estruturas foliculares, os folículos ovarianos, que são os ovócitos envolvidos por células foliculares. Ovogônias: formam ninhos perifericamente localizados, contendo células com núcleo grande e oval associadas com uma única célula folicular. Ovócitos I: o citoplasma é discretamente basófilo; seu núcleo é esférico e apresenta poucos nucléolos, geralmente se observa um ou dois; as células foliculares se apresentam em uma camada (epitélio pavimentoso simples) que circunda a célula germinativa em estado pré-vitelogênico. Ovócitos II: a célula é maior que a anterior e o citoplasma torna-se mais basófilo; o núcleo apresenta raros nucléolos na periferia e muitos cromossomos constituindo arranjos irregulares, é quando se inicia o estádio perinucleolar. Ovócitos III: o citoplasma adquire intensa acidofilia; a região periférica do citoplasma é preenchida por inclusões vitelínicas que ainda não ocorrem na região interna; inicia-se a síntese de pigmentos; o envoltório folicular apresenta três camadas: uma interna acelular (envoltório vitelínico) e duas camadas de células foliculares. Ovócitos IV: uma característica deste estádio é a diferenciação entre o pólo animal e o vegetal; o núcleo ou vesícula germinativa se desloca para o hemisfério animal e os pigmentos conferem uma cor marrom escura; a vitelogênese é intensa e o vitelo ocupa todo o citoplasma

A comparative study of the extracutaneous pigmentary system in three anuran amphibian species evaluated during the breeding season.

The present investigation examined the extracutaneous pigmentation pattern of three species of anuran amphibians, Dendropsophus nanus, Physalaemus cuvieri, and Rhinella schneideri, during the course of their breeding seasons. Pigmentation intensity in the different organs was graded on a 4-category scale, in which category 0 refers to organs without pigment and category 3 refers to intensely pigmented organs, with 2 intermediate stages of progressively stronger pigmentation. Rhinella schneideri showed testicular pigmentation, with intra-specific variation (categories 0 and 1). In P. cuvieri the pigmentation in the lungs varied in time: all the animals showed pigmentation (category 1) at the beginning of the breeding season, and as the season progressed the absence of pigments became the most common pattern. In the liver of the first animals collected, the pigment intensity was high (category 2) with many iridophores present, but in the last specimens collected no iridophores were found. The variation in D. nanus occurred in the kidneys, where animals collected at the beginning of the season did not show pigmentation. Renal veins displayed few melanocytes (category 1); animals collected at the end of the season showed more pigmentation in the kidneys (category 2), whereas in the renal veins the intensity remained the same. The changes observed in the extracutaneous pigment system in some organs, during the reproductive period, may be due to physiological alterations or may represent a species-specific characteristic

Histological aspects and structural characteristics of the testes of Dendropsophus minutus (Anura, Hylidae)

The present study describes morphological aspects of testes and presents a general characterization of the seminiferous elements of Dendropsophus minutus (Peters, 1872). Twenty samples of the species were used; after macroscopic descriptions the testes were submitted to histological routine for microscopic analysis. Anatomically, the testes measured 1.90 +/- 0.13 torn, and were oval and milky-white. In relation to microscopic aspects, it was observed in D. minutus, as well as in anuran amphibians, that spermatogenesis occurs in the seminiferous tubule where elements of the germ epithelium are organized in spermatogenetic cysts. Each cyst contains cells in the same stage of differentiation. Characterization of each cellular type enables the identification and differentiation of germ lineage cells. Spermatogonia 1, found at the epithelial base, are the largest of the lineage cells and are usually present in association with Sertoli cells present next to the basal membrane. During the mitotic proliferation phase, cysts containing variable numbers of spermatocytes II are originated; these spermatocytes are smaller and similar inside the cyst. Spermatocytes I are developed after some morphological changes; these spermatocytes are large cells with a spherical nucleus and different degrees of nuclear compaction. Spermatocytes II, highly numerous cells resultant from the first meiotic division, are much smaller than their antecedents. A second meiotic division produces haploid cell formation, specifically spermatids I, which through cellular differentiation form spermatids II. Spermatids II are elongated and organized in bundles supported by Sertoli cells. Spermatozoids appear during the spermiogenesis process and in their most advanced stage they lose their fascicular organization and are released in the tubular lumen, where they follow a pathway through the duct system. (C) 2008 Elsevier Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES