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991.
Marta Bellver Susana Lemos da Costa Begoa Astrain Sanchez Vitor Vasconcelos Ralph Urbatzka 《Marine drugs》2021,19(3)
Obesity is a complex metabolic disease, which is increasing worldwide. The reduction of dietary lipid intake is considered an interesting pathway to reduce fat absorption and to affect the chronic energy imbalance. In this study, zebrafish larvae were used to analyze effects of cyanobacteria on intestinal lipid absorption in vivo. In total, 263 fractions of a cyanobacterial library were screened for PED6 activity, a fluorescent reporter of intestinal lipases, and 11 fractions reduced PED6 activity > 30%. Toxicity was not observed for those fractions, considering mortality, malformations or digestive physiology (protease inhibition). Intestinal long-chain fatty acid uptake (C16) was reduced, but not short-chain fatty acid uptake (C5). Alteration of lipid classes by high-performance thin-layer chromatography (HPTLC) or lipid processing by fluorescent HPTLC was analyzed, and 2 fractions significantly reduced the whole-body triglyceride level. Bioactivity-guided feature-based molecular networking of LC-MS/MS data identified 14 significant bioactive mass peaks (p < 0.01, correlation > 0.95), which consisted of 3 known putative and 11 unknown compounds. All putatively identified compounds were known to be involved in lipid metabolism and obesity. Summarizing, some cyanobacterial strains repressed intestinal lipid absorption without any signs of toxicity and could be developed in the future as nutraceuticals to combat obesity. 相似文献
992.
Samuel Cavalcante do Amaral Patrick Romano Monteiro Joaquim da Silva Pinto Neto Gustavo Marques Serra Evonnildo Costa Gonalves Luciana Pereira Xavier Agenor Valadares Santos 《Marine drugs》2021,19(1)
Cyanobacteria are a rich source of secondary metabolites with a vast biotechnological potential. These compounds have intrigued the scientific community due their uniqueness and diversity, which is guaranteed by a rich enzymatic apparatus. The ribosomally synthesized and post-translationally modified peptides (RiPPs) are among the most promising metabolite groups derived from cyanobacteria. They are interested in numerous biological and ecological processes, many of which are entirely unknown. Microviridins are among the most recognized class of ribosomal peptides formed by cyanobacteria. These oligopeptides are potent inhibitors of protease; thus, they can be used for drug development and the control of mosquitoes. They also play a key ecological role in the defense of cyanobacteria against microcrustaceans. The purpose of this review is to systematically identify the key characteristics of microviridins, including its chemical structure and biosynthesis, as well as its biotechnological and ecological significance. 相似文献
993.
Javier Muoz-Garcia Mattia Mazza Cyrille Alliot Corinne Sinquin Sylvia Colliec-Jouault Dominique Heymann Sandrine Huclier-Markai 《Marine drugs》2021,19(3)
Antimetastatic properties on both murine and human osteosarcoma cell lines (POS-1 and KHOS) have been evidenced using exopolysaccharide (EPS) derivatives, produced by Alteromonas infernus bacterium. These derivatives had no significant effect on the cell cycle neither a pro-apoptotic effect on osteosarcoma cells. Based on this observation, these EPSs could be employed as new drug delivery systems for therapeutic uses. A theranostic approach, i.e., combination of a predictive biomarker with a therapeutic agent, has been developed notably by combining with true pair of theranostic radionuclides, such as scandium 47Sc/44Sc. However, it is crucial to ensure that, once complexation is done, the biological properties of the vector remain intact, allowing the molecular tropism of the ligand to recognize its molecular target. It is important to assess if the biological properties of EPS evidenced on osteosarcoma cell lines remain when scandium is complexed to the polymers and can be extended to other cancer cell types. Scandium-EPS complexes were thus tested in vitro on human cell lines: MNNG/HOS osteosarcoma, A375 melanoma, A549 lung adenocarcinoma, U251 glioma, MDA231 breast cancer, and Caco2 colon cancer cells. An xCELLigence Real Cell Time Analysis (RTCA) technology assay was used to monitor for 160 h, the proliferation kinetics of the different cell lines. The tested complexes exhibited an anti-proliferative effect, this effect was more effective compared to EPS alone. This increase of the antiproliferative properties was explained by a change in conformation of EPS complexes due to their polyelectrolyte nature that was induced by complexation. Alterations of both growth factor-receptor signaling, and transmembrane protein interactions could be the principal cause of the antiproliferative effect. These results are very promising and reveal that EPS can be coupled to scandium for improving its biological effects and also suggesting that no major structural modification occurs on the ligand. 相似文献
994.
de Carvalho LB Alves PL González-Torralva F Cruz-Hipolito HE Rojano-Delgado AM De Prado R Gil-Humanes J Barro F de Castro MD 《Journal of agricultural and food chemistry》2012,60(2):615-622
Digitaria insularis biotypes resistant to glyphosate have been detected in Brazil. Studies were carried out in controlled conditions to determine the role of absorption, translocation, metabolism, and gene mutation as mechanisms of glyphosate resistance in D. insularis. The susceptible biotype absorbed at least 12% more (14)C-glyphosate up to 48 h after treatment (HAT) than resistant biotypes. High differential (14)C-glyphosate translocation was observed at 12 HAT, so that >70% of the absorbed herbicide remained in the treated leaf in resistant biotypes, whereas 42% remained in the susceptible biotype at 96 HAT. Glyphosate was degraded to aminomethylphosphonic acid (AMPA), glyoxylate, and sarcosine by >90% in resistant biotypes, whereas a small amount of herbicide (up to 11%) was degraded by the susceptible biotype up to 168 HAT. Two amino acid changes were found at positions 182 and 310 in EPSPS, consisting of a proline to threonine and a tyrosine to cysteine substitution, respectively, in resistant biotypes. Therefore, absorption, translocation, metabolism, and gene mutation play an important role in the D. insularis glyphosate resistance. 相似文献
995.
Darriet F Bendahou M Costa J Muselli A 《Journal of agricultural and food chemistry》2012,60(6):1494-1502
The chemical compositions of the aerial parts essential oils of Chamaemelum mixtum (L.) Alloni from Corsica and Sardinia were investigated employing gas chromatography and gas chromatography-mass spectrometry (GC-MS). The structure of (Z)-heptadeca-9,16-dien-7-one, a natural compound not previously described, was elucidated by GC-MS (electron impact and chemical ionization) and one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy. The variation in C. mixtum essential oil was studied, and statistical analysis showed the clustering of oil samples into three groups according to the amount of oxygenated compounds; these groups correlated to the harvest area. The strong biological activity of the oxygenated fraction (minimum inhibitory concentration of <0.1 mg/mL) of the Corsican oil against Candida albicans , Citrobacter frendii , Enterococcus faecalis , Escherichia coli , Klebsiella pneumoniae , Listeria monocytogenes , and Staphyllococcus aureus can be attributed to the presence of irregular monoterpene alcohols and (Z)-heptadeca-9,16-dien-7-one. 相似文献
996.
Rogério O. Pinho Hugo H. Shiomi Daniel M.A. Lima Edson V. Costa Alberto Y. Chaya Paulo S. Lopes Simone E.F. Guimarães José D. Guimarães 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(5):357-361
The objective of this study was to assess parameters of sexual behavior, seminal characteristics, testicular measurements, and their correlations in Piau boars. A total of 169 observations of the sexual behavior and prelude duration (courting) of 10 Piau boars aged from 0.8 to 6.4 years were made; semen was also collected from these animals. The testicular length (TL), testicular width (TW), testicular shape (TS; 1-5), and testicular volume (TV) of these animals were measured. The seminal physical and morphological characteristics of 60 ejaculates from 6 boars were assessed for volume of ejaculate (VOL), volume of the gelatinous portion (VOLGEL), aspect (ASP), sperm motility (MOT), spermatic vigor (VIG), spermatic concentration per milliliter (CONCML), total concentration (CONCT), and morphological characteristics (major defects [MAJDEF]; minor defects [MINDEF]; and total defects [TDEF]). The animals were subdivided into 3 age groups: G1 (0.8-2.0 years old), G2 (2.1-3.6 years old), and G3 (3.7 and 6.4 years olds). The physiological signs observed included duration of prelude (12.1 ± 4.1 minutes), time to collect semen (5.2 ± 1.8 minutes), nasonasal or genital contact behavior (71.6%), saliva emission (85.2%), urination during prelude (10.1%), penile exposure before collection (26.6%), flank stimulus (81.7%), chewing behavior (95.3%), and biting of the female or dummy (74.6%). The mean values of TL, TW, and TV were 11.8 ± 2.2 cm, 6.2 ± 1.3 cm and 754.1 ± 283.5 cm3, respectively. The older animals had the highest mean values of testicular measurements (P < 0.05) but the lowest mean values of CONCML and CONCT (P < 0.05). All the animals presented similar patterns of ejaculates (P > 0.05); the mean values of VOL, VOLGEL, MOT, VIG, and CONCT were 149.1 ± 51.1 mL, 29.7 ± 10.0 g, 76.2% ± 9.5%, 3.3 ± 0.5, and 29.4 ± 19.5 × 109 total sperm in the ejaculate, respectively. The prevalence rates of defects were 5.9% ± 2.6% for MAJDEF, 10.2% ± 4.0% for MINDEF, and 16.2% ± 5.5% for TDEF; all animals were classified as being sound for breeding. The assessed characteristics were similar to those observed in swine of commercial lineages and within the standards established by the Brazilian College of Animal Reproduction for the species. 相似文献
997.
Sara Maria Chalfoun Samantha Brettas Oliveira Igor Chalfoun Fernanda Carvalho Costa Eliane Maria De Souza Xisto 《农业科学与技术》2013,(9):689-696
Tbio is a start-up created to give support to commercialize the products of the biofactory installed in the Federal University of Lavras, Minas Gerais State, Brazil, part of the Innovation Program developed by this University. Its specialty is to innovate, through biological solutions with the vision of the future, once there is a strong demand of food and beverages free of chemical residues and with lower employing of these substances along the production chain by several consumers. The innovative products are generated from microorganisms tested regarding its capacity to promote yield protection, pests and disease control, acceleration of the desmucilage waste water treatment, and improvement of process of faster solubilization, that depends on natural phosphate fertilizers. The goal of this article is to approach the activities that have been developed in this start-up and the knowledge about biocontrol and natural antimicrobials produced by fungi resulting in innovative products to attend the world claim for products free of chemical residues of any kind and harmless to the consumers, environment and workers. 相似文献
998.
Rafael Torres de Souza Rodrigues Mario Luiz Chizzotti Daniel Ribeiro Menezes Fernando Santos Costa Carlos Wagner de Souza Wanderley Álvaro Santos Lisboa Neto 《Tropical animal health and production》2013,45(4):1031-1037
This experiment was conducted to evaluate the effect of different levels of substitution (0, 33.3, 66.7, and 100 %) of elephant grass by hay of mango tree pruning (HMTP) on intake and digestibility in cattle and on the in vitro gas production. Moreover, the effect of tannin in HMTP on the gas production and in vitro degradability of the dry matter was evaluated, using polyethylene glycol (PEG). The intake and digestibility were evaluated in a double 4?×?4 square Latin design, using eight Holstein intact bulls. To evaluate the gas production and degradability, in vitro semi-automated gas production technique was used. The substitution of elephant grass by HMTP decreased the intake (P?<?0.05) and the digestibility (P?<?0.05) of the nutrients and also the gas production (P?<?0.05). Furthermore, the utilization of PEG as a tannin-complexing agent increased the gas production and degradability of the HMTP (P?<?0.05). It was concluded that the high cell wall lignification and the presence of tannin limit the use of HMTP as the only source of roughage in cattle diets. 相似文献
999.
1000.
L. N. S. Santana L. V. M. Barbosa F. B. Teixeira A. M. P. Costa L. M. P. Fernandes R. R. Lima 《Anatomia, histologia, embryologia》2013,42(6):410-414
The aim of this study was to describe the dentine morphology of sloths (Bradypus tridactylus). The sloth teeth were removed and prepared for light microscopy (LM) and scanning electron microscopy analyses (SEM). LM revealed two patterns of tubular dentins: an outer with dentinary tubules over the all tooth length and one in the inner part with larger diameter and more spaced tubules, when compared to those present in the outer dentine. These findings were confirmed by SEM, which revealed a tubular pattern in the outer dentine like in humans. The inner dentine displayed pared grouped tubules that were characterized as vascular channels. It can be concluded that this sloth species present two types of dentins: an inner dentin (ortodentin) and an outer dentin characterized as a vascular dentin. This suggests a partial evolutive/adaptive process of this dental tissue, as compared to other mammalian species. 相似文献