Atividade antimicrobiana e citotoxicidade in vitro do óleo essencial de Tagetes minuta L. visando à aplicação no controle da mastite bovina / In vitro antibacterial and cytotoxicity activities of Tagetes minuta L. essential oil towards bovine mastitis treatment

O objetivo deste estudo foi avaliar a atividade antimicrobiana in vitro do óleo essencial de Tagetes minuta L. contra Staphylococcus aureus e Escherichia coli e a citotoxicidade sobre células epiteliais da glândula mamária bovina (MAC-T), visando a seu uso no tratamento da mastite bovina. A análise qualitativa do óleo revelou cis-tagetona (24,24%), di-hidrotagetona (16,65%), 1,3,6-octatrieno-3,7-dimetil-E (13,61%), trans-ocimenona (13,52%) e cis-ocimenona (10,06%) como compostos majoritários. Nos ensaios da atividade antimicrobiana, a concentração inibitória mínima (CIM) verificada foi de 1 mg/mL para a cepa padrão (ATCC 25923), cinco isolados de S. aureus provenientes de leite de vacas com mastite e a cepa padrão resistente à meticilina (MRSA) (ATCC 33592). Para a cepa padrão de E. coli (ATCC 8739) e dois isolados de leite de vacas com mastite, a CIM foi de 3 mg/mL. Elevado efeito citóxico do óleo sobre as células da linhagem MAC-T foi constatado. Concentrações superiores a 10 (g/mL do óleo resultaram em mais de 90% de morte celular. Tais resultados sugerem que, apesar da atividade antimicrobiana contra agentes causadores da mastite bovina, a utilização intramamária do óleo de T. minuta não seria recomendada. É importante destacar a sensibilidade da cepa MRSA ao óleo essencial, o que evidencia seu potencial como antisséptico e sanitizante.(AU)

The aim of this study was to evaluate the in vitro antimicrobial activity of Tagetes minuta L. essential oil against Staphylococcus aureus and Escherichia coli, and its cytotoxicity to bovine mammary epithelial cells (MAC-T line), aiming at its use for bovine mastitis treatment. The qualitative analysis of the oil by GC-MS identified cis-tagetone (24.24%), dihydrotagetone (16.65%), 1,3,6-Octatriene 3,7-Dimethyl-E (13.61%); trans-ocimenone (13.52%) and cis-ocimenone (10.06%) as major compounds. Antimicrobial activity was determined by broth microdilution technique and revealed the minimum inhibitory concentration of 1mg/mL for the standard strain of S. aureus (ATCC 25923) and five bacterias isolated from mastitic milk, including a multiresistant strain (ATCC 33592); and 3mg/ml for the standard strain of E. coli (ATCC 8739) and two bacterias isolated from mastitic milk. However, a strong citotoxic effect on MAC-T cells was found. Oil concentrations from 10(g/mL resulted in over 90% of cell death. The results suggest that although the antimicrobial activity was identified against the main agents of bovine mastitis, the intramammary use of T. minuta oil may not be recommended. On the other hand, it is important to highlight the sensibility of the MSRA strain to the essential oil, which evidences its potential as an antiseptic or sanitizer.(AU)

Chemical characterization and complement modulating activities of an arabinogalactan-protein-rich fraction from an aqueous extract of avocado leaves.

The aim of this study was to chemically characterize an arabinogalactan-protein-rich fraction (FRAGP) obtained from an aqueous extract of avocado leaves and investigate its effects on the classical pathway of the complement system. The FRAGP contained 4.6% ±â€¯1.8%, 22.5% ±â€¯4.9%, and 76.7% ±â€¯8.8% of total protein, arabinogalactan-protein, and carbohydrates, respectively. Arabinose and galactose were the main monosaccharide constituents. FT-IR and NMR data, together with linkage analyses, indicated the presence of a structure that included a (1 → 3)-linked ß-D-Galp main chain, mainly substituted at O-6 by Gal and Ara residues, which was characteristic of a type II arabinogalactan. The effect of FRAGP on the classical pathway of complement system was examined by a hemolytic fixation test and comparing with heparin, which was used as a control for inhibition. With pre-incubation, the IC50 of FRAGP was 1.90 ±â€¯1.1 µg/mL, which was similar to that of heparin (IC50 = 2.90 ±â€¯0.3 µg/mL). Without pre-incubation, the IC50 values were 18.6 ±â€¯3.7 and 8.0 ±â€¯4.1 µg/mL for FRAGP and heparin, respectively. Collectively, these results suggested that FRAGP has an inhibitory effect on the classical pathway of the complement system.

Modulating Effects of Arabinogalactans from Plant Gum Exudates on Human Complement System.

Gum arabic and cashew nut tree gum exudate polysaccharide (CNTG) are plant polysaccharides composed of galactose and arabinose known as arabinogalactans (AGs). Although these fractions are used in food and pharmaceutical industry, cases of allergic reactions were described in clinical reports. As AGs were reported as modulators of the classical (CP) and alternative pathways (AP) of complement system (CS), in the present work, we investigate whether gum arabic and CNTG have an effect on both CS pathways. The complement fixation tests were performed with (CP-30 and AP-30) and without pre-incubation (CP-0 and AP-0). For CP-30, CNTG and gum arabic (833 µg/ml) showed a reduction of 28.0% (P = 0.000174) and 48.5% (P = 0.000143), respectively, on CP-induced haemolysis. However, no effect was observed for CP-0 in the CP-induced haemolysis. For AP-30, both CNTG and gum arabic (833 µg/ml) showed 87% reduction on the CP-induced haemolysis, with IC50 values of 100 and 7 µg/ml, respectively. For AP-0, a reduction of 11.3% for gum arabic and no effect for the CNTG on the CP-induced haemolysis were observed. These results suggested that gum arabic and CNTG could be acting as activators of the CS. Thus, this effect on the CS, especially on the AP, which accounts for up to 80-90% of total CS activation, indicates that both fractions may be harmful because of their potential pro-inflammatory action. Considering that CS activation induces inflammatory response, further studies confirming this immunomodulatory effect of these fractions are required to insure their safe use.

Effect of the native polysaccharide of cashew-nut tree gum exudate on murine peritoneal macrophage modulatory activities.

The native polysaccharide of cashew-nut tree gum exudate (CNTG) and its arabinogalactan-protein component (CNTG-AGP) were tested by using immuno-stimulant and anti-inflammatory in vitro assays of murine peritoneal macrophage activities. In the assay for immuno-stimulant activity (without previous treatment with lipopolysaccharide; LPS), CNTG increased the production of interleukin (IL)-10 and both CNTG and CNTG-AGP decreased the concentrations of IL6. When the macrophages were incubated in the presence of LPS and CNTG a decrease in the levels of nitric oxide (NO(·)) and IFN-γ was observed. The results could explain the popular use of CNTG as an anti-inflammatory. In addition, CNTG is the main component of the cashew-nut tree gum exudate, which has been considered a versatile polymer with potential pharmaceutical and food industry applications. These data may contribute to the study of the immunomodulation activity of plant polysaccharides, as well as encourage future experiments in the field of cashew-nut tree gum exudate applications.

Atividade ovicida e larvicida do extrato hidroalcoólico de Artemisia annua sobre parasitas gastrintestinais de bovinos / Ovicidal and larvicidal activity of Artemisia annua hydroalcoholic extract against gastrointestinal parasites in cattle

Os parasitas gastrintestinais causam enorme prejuízo econômico na bovinocultura, tanto nacional como mundial, ocasionado principalmente por Bunostumom sp., Cooperia sp. e Trichostrongylus sp. O objetivo deste trabalho foi determinar a eficácia in vitro do extrato hidroalcoólico de Artemisia annua (H.7) frente a esses endoparasitas. O H.7 foi produzido com sete dias de percolação a 4ºC e posteriormente liofilizado. Com esse fitoterápico, realizaram-se testes de eclodibilidade de ovos (TEO) e de migração larvar em ágar (TMLA), com seis repetições, com concentrações crescentes (0,78 a 50mg/mL). Para analisar a composição química do fitoterápico, procedeu-se à marcha fitoquímica completa. No TEO, a eficácia variou de 94,08±2,58% na maior concentração a 15,67±0,97% na menor concentração. Já no TMLA os valores encontrados variaram de 90,05±0,55% a 4,12±0,46%. Nas análises fitoquímicas, foram encontrados diversos compostos com propriedades de combater os nematódeos, tanto direta como indiretamente. Os resultados obtidos nos testes in vitro evidenciam que o extrato produzido possui potencial de combater nematódeos gastrintestinais de bovinos. Novos estudos devem ser realizados buscando maximizar a eficácia do H.7 e de outras extrações obtidas a partir de A. annua, uma vez que foram demonstrados excelentes resultados em ambos os experimentos.

Gastrointestinal parasites cause economic losses to the cattle production, in Brazil and worldwide, mainly caused by Bunostumom sp., Cooperia sp. and Trichostrongylus sp. The aim of this study was to determine the in vitro efficacy of hydroalcoholic extract of Artemisia annua (H.7) against these parasites. The H.7 was produced after 7 days of storage at 4°C and then lyophilized. With this herbal the egg hatch test (EHT) and larval migration inhibition (LMI) were performed,in six replicates with different concentrations (0.78 to 50mg/mL). To analyze the chemistry composition the complete phytochemical screening was done. In EHT efficiency ranged from 94.08±2.58% at the highest concentration to 15.67± 0.97% in the lowest concentration. In LMI test the values ranged from 90.05±0.55% to 4.12±0.46%. Phytochemical tests showed many chemical compounds with anthelmintic properties. The results obtained in biochemical tests together with those found in in vitro tests showed that the extract produced has the potential to combat intestinal nematodes of cattle. Further studies should be conducted to maximize the effectiveness of H.7 and other extractions from A. annua, because it demonstrated excellent results in both experiments.

NMR and rheological study of Aloe barbadensis partially acetylated glucomannan.

The structural and rheological properties of the Aloe extract (AE) and the polysaccharidic fraction (PF) obtained from the leaves pulp of Aloe barbadensis Miller were investigated. Structural analyses carried out by composition, methylation analysis and NMR spectroscopy showed that PF is mainly constituted by a partially acetylated 4-linked ß-d-glucomannan. The acetyl groups are located at C-2, C-2 and C-3, C-3 and/or C-6. The acetylation pattern of this type of polysaccharide was for the first time established using bidimensional NMR analyses. AE and PF aqueous solutions at 25°C showed a non-Newtonian behavior (with pseudoplastic characteristics), however PF showed higher apparent viscosity than AE. Dynamic oscillatory analyses showed that both samples, at the same concentration, behaved as a concentrated solution. PF presented higher values of G' compared with those of AE and this behavior could be consequence of its higher content in partially acetylated glucomannan.

Carotenoid extraction from the gonad of the scallop Nodipecten nodosus (Linnaeus, 1758) (Bivalvia: Pectinidae).

In marine bivalve mollusks, unsaturated molecules called carotenoids are present in the natural diet and play an important role in different biological process, especially in reproduction. In order to gain more insights into these compounds in Nodipecten nodosus it was necessary to develop a suitable protocol for extraction of carotenoids from the gonads. Female gonads of cultured scallops (75 mm length) were lyophilized and macerated in liquid N2. To verify the effect of composition in organosolvents on the extracting solutions, two organic solvents were tested: acetone and hexane (Ac = O:Hex) at four ratios, 1:1, 1:3, 1:5, and 2:3, in four static extraction times: 0, 5, 10, and 15 minutes. Total carotenoids and astaxanthin contents were determined in the crude extracts by UV-visible spectrophotometry and high performance liquid chromatography (HPLC), respectively. Triplicate aliquots of 50 mg were used for each treatment. The results indicated that the best single extraction (0.312 +/- 0.016 microg carotenoids/mg) was attained with Ac = O: Hex 1:3, for 15 minutes. Through exhaustive extraction methodology (10x), a superior yield (0.41 +/- 0.001 microg carotenoids/mg) was obtained from a gonad sample in comparison to the highest value found for a single extraction. Astaxanthin content was reduced by 8.6% in carotenoid extract preservation assay, i.e., -18 degrees C, 26 days incubation, under N2 atmosphere.

Carotenoid extraction from the gonad of the scallop Nodipecten nodosus (Linnaeus, 1758) (Bivalvia: Pectinidae) / Extração de carotenóides da gônada da vieira Nodipecten nodosus (Bivalvia: Pectinidae)

In marine bivalve mollusks, unsaturated molecules called carotenoids are present in the natural diet and play an important role in different biological process, especially in reproduction. In order to gain more insights into these compounds in Nodipecten nodosus it was necessary to develop a suitable protocol for extraction of carotenoids from the gonads. Female gonads of cultured scallops (75 mm length) were lyophilized and macerated in liquid N2. To verify the effect of composition in organosolvents on the extracting solutions, two organic solvents were tested: acetone and hexane (Ac = O:Hex) at four ratios, 1:1, 1:3, 1:5, and 2:3, in four static extraction times: 0, 5, 10, and 15 minutes. Total carotenoids and astaxanthin contents were determined in the crude extracts by UV-visible spectrophotometry and high performance liquid chromatography (HPLC), respectively. Triplicate aliquots of 50 mg were used for each treatment. The results indicated that the best single extraction (0.312 ± 0.016 µg carotenoids/mg) was attained with Ac = O: Hex 1:3, for 15 minutes. Through exhaustive extraction methodology (10x), a superior yield (0.41 ± 0.001 µg carotenoids/mg) was obtained from a gonad sample in comparison to the highest value found for a single extraction. Astaxanthin content was reduced by 8.6 percent in carotenoid extract preservation assay, i.e., -18 °C, 26 days incubation, under N2 atmosphere.

Em moluscos bivalves marinhos, carotenóides insaturados estão presentes na dieta natural, com um importante papel em diversos processos biológicos, em especial na reprodução. A elucidação dos efeitos destes compostos em Nodipecten nodosus requer o desenvolvimento de um protocolo adequado para a extração de carotenóides das gônadas desses animais. Para isso, gônadas de vieiras cultivadas (75 mm de comprimento) foram liofilizadas e maceradas em N2 líquido. Amostras em triplicata com 50 mg foram coletadas para a utilização em cada tratamento. Os conteúdos de carotenóides totais e astaxantina foram determinados via espectrofotometria de luz UV-visível e cromatografia líquida de alta eficiência (CLAE), respectivamente. O efeito da composição em organosolventes das soluções de extração foi testado utilizando-se acetona (Ac = O) e hexano (Hex) em quatro proporções (Ac = O:Hex): 1:1, 1:3, 1:5, e 2:3; em quatro tempos de extração: 0, 5, 10, e 15 minutos. Os resultados mostraram que o melhor rendimento de extração (0,312 ± 0,016 µg carotenóides/mg) foi obtido com Ac = O:Hex, 1:3, por 15 minutos. Com a utilização de protocolo de extração exaustiva (10x), uma quantidade superior (0,41 ± 0,001 µg de carotenóides/mg) foi obtida de amostras de gônada, comparativamente aos valores obtidos em extrações únicas. O conteúdo de astaxantina foi reduzido em 8,6 por cento em testes de preservação deste metabólito em extratos crus (-18 °C, 26 dias de incubação em atmosfera de N2).