Phytochemical Characterization of Cannabis sativa L. Roots from Northeastern Brazil

This article describes the phytochemical study of Cannabis sativa roots from northeastern Brazil. The dried plant material was pulverized and subjected to exhaustive maceration with ethanol at room temperature, obtaining the crude ethanolic extract (Cs-EEBR). The volatile compounds were analyzed by gas chromatography coupled with mass spectrometry (GC/MS), which allowed to identify 22 compounds by comparing the linear retention index (LRI), the similarity index (SI) and the fragmentation pattern of the constituents with the literature. By this technique the major compounds identified were: friedelan-3-one and β-sitosterol. In addition, two fractions were obtained from Cs-EEBR by classical column chromatography and preparative thin layer chromatography. These fractions were analyzed by NMR and IR and together with the mass spectrometry data allowed to identify the compounds: epifriedelanol, friedelan-3-one, β-sitosterol and stigmasterol. The study contributed to the phytochemical knowledge of Cannabis sativa, specifically the roots, as there are few reports on the chemical constituents of this part of the plant.     

Action Spectra for Conversions of Phycochrome c from Nostoc muscorum

The reversibly photochromic pigment, phycochrome c, was extracted from the blue-green alga Nostoc muscorum strain A. Action spectra were determined for in vitro conversions of the pigment from the short wavelength to the long wavelength form and vice versa. The action peak for the absorbance decrease at 650 nm is at 630 nm. During this decrease there is only a slight increase of the absorbance in the green region. Green and yellow light (maximum efficiency at 580 nm) completely restores absorbance at 650 nm. The observations are explained by the existence of three spectrally different forms of phycochrome c: P^c₆₃₀ and P^c₆₅₀ which equilibrate in darkness and P^c₅₈₀ which is reversibly photoconvertible to P^c₆₃₀. We have also measured the absorbance changes brought about by saturating irradiations with light of various wavelengths (“photostationary state spectrum”). Extreme photostationary states were obtained with about 650 nm and 500 nm light.     

Control of cell volume in the J774 macrophage by microtubule disassembly and cyclic AMP

We have explored the possibilities that cell volume is regulated by the status of microtubule assembly and cyclic AMP metabolism and may be coordinated with shape change. Treatment of J774.2 mouse macrophages with colchicine caused rapid microtubule disassembly and was associated with a striking increase (from 15-20 to more than 90 percent) in the proportion of cells with a large protuberance at one pole. This provided a simple experimental system in which shape changes occurred in virtually an entire cell population in suspension. Parallel changes in cell volume could then be quantified by isotope dilution techniques. We found that the shape change caused by colchicine was accompanied by a decrease in cell volume of approximately 20 percent. Nocodozole, but not lumicolchicine, caused identical changes in both cell shape and cell volume. The volume loss was not due to cell lysis nor to inhibition of pinocytosis. The mechanism of volume loss was also examined. Colchicine induced a small but reproducible increase in activity of the ouabain-sensitive Na(+), K(+)-dependent ATPase. However, inhibition of this enzyme/transport system by ouabain did not change cell volume nor did it block the colchicines-induced decrease in volume. One the other hand, SITS (4’acetamido, 4-isothiocyano 2,2’ disulfonic acid stilbene), an inhibitor of anion transport, inhibited the effects of colchicines, thus suggesting a role for an anion transport system in cell volume regulation. Because colchicine is known to activate adenylate cyclase in several systems and because cell shape changes are often induced by hormones that elevate cyclic AMP, we also examined the effects of cyclic AMP on cell volume. Agents that act to increase syclic AMP (cholera toxin, which activates adenylate cyclase; IBMX, and inhibitor of phosphodiesterase; and dibutyryl cyclic AMP) all caused a volume decrease comparable to that of colchicine. To define the effective metabolic pathway, we studied two mutants of J774.2, one deficient in adenylate cyclase and the other exhibiting markedly reduced activity of cyclic AMP-dependent protein kinase. Cholera toxin did not produce a volume change in either mutant. Cyclic AMP produced a decrease in the cyclase-deficient line comparable to that in wild type, but did not cause a volume change in the kinase- deficient line. This analysis established separate roles for cyclic AMP and colchicine. The volume decrease induced by cyclic AMP requires the action of a cyclic AMP-dependent protein kinase. Colchicine, on the other hand, induced a comparable volume change in both mutants and wild type, and thus does not require the kinase.     

Developmental stability in brown trout: are there any effects of heterozygosity or environmental stress?

We studied the developmental stability of brown trout, Salmo trutta L., in 10 populations (five acidified, five control) in Norway, measured as fluctuating asymmetry (FA) and departure from the morphological norm. We measured four meristic and four morphometric characters, and scored the level of biochemical heterozygosity at 49 loci (20 polymorphic). We reared eggs of a single population in a hatchery using four different water qualities (three replicates of each treatment) to test the effect of acidification stress on developmental instability. There were no significant differences in the level of FA, in departure from the morphological norm between brown trout sampled from lakes with acidified or control water qualities, or in brown trout hatched at different water qualities. There was no correlation between level of heterozygosity and FA or departure from the morphological norm, either when tested within populations or among populations. There were no single-locus effects on developmental stability tested for 11 loci. We conclude that measures of developmental stability or morphological variability are not useful for detecting acidification stress in brown trout. Furthermore, we conclude that developmental stability in our material varies independently of heterozygosity.     

Production of Lactic Acid Enantiomers by Lactobacillus Strains under Limited Dissolved Oxygen Conditions in the Presence of a Pentose Fraction

Applied Biochemistry and Microbiology - Lactic acid has a privileged position in the family of carboxylic substances due to its several applications, including the production of biodegradable...     

A novel disorder caused by defective biosynthesis of N-linked oligosaccharides due to glucosidase I deficiency

Glucosidase I is an important enzyme in N-linked glycoprotein processing, removing specifically distal alpha-1,2-linked glucose from the Glc3Man9GlcNAc2 precursor after its en bloc transfer from dolichyl diphosphate to a nascent polypeptide chain in the endoplasmic reticulum. We have identified a glucosidase I defect in a neonate with severe generalized hypotonia and dysmorphic features. The clinical course was progressive and was characterized by the occurrence of hepatomegaly, hypoventilation, feeding problems, seizures, and fatal outcome at age 74 d. The accumulation of the tetrasaccharide Glc(alpha1-2)Glc(alpha1-3)Glc(alpha1-3)Man in the patient's urine indicated a glycosylation disorder. Enzymological studies on liver tissue and cultured skin fibroblasts revealed a severe glucosidase I deficiency. The residual activity was <3% of that of controls. Glucosidase I activities in cultured skin fibroblasts from both parents were found to be 50% of those of controls. Tissues from the patient subjected to SDS-PAGE followed by immunoblotting revealed strongly decreased amounts of glucosidase I protein in the homogenate of the liver, and a less-severe decrease in cultured skin fibroblasts. Molecular studies showed that the patient was a compound heterozygote for two missense mutations in the glucosidase I gene: (1) one allele harbored a G-->C transition at nucleotide (nt) 1587, resulting in the substitution of Arg at position 486 by Thr (R486T), and (2) on the other allele a T-->C transition at nt 2085 resulted in the substitution of Phe at position 652 by Leu (F652L). The mother was heterozygous for the G-->C transition, whereas the father was heterozygous for the T-->C transition. These base changes were not seen in 100 control DNA samples. A causal relationship between the alpha-glucosidase I deficiency and the disease is postulated.     

de novo转录组学分析华南地区入侵植物五爪金龙代谢特征

为探究华南地区严重入侵植物五爪金龙(Ipomoea cairica)生物入侵的分子机制,对五爪金龙及其近缘种七爪金龙(I. digitata)和裂叶牵牛(I. nil)进行de novo转录组测序和组装,得到56551条unigenes,其中56522条得到注释,7815条GO注释,15615条COG注释,180201条KEGG数据库注释。转录组分析结果表明,五爪金龙氮代谢通路关键酶基因的表达高于对照。次生代谢关键酶(PAL、4CL、CAD、查耳酮合酶、苯基丙乙烯酮异构酶、槲皮黄3-O-甲基转移酶等)基因在五爪金龙与七爪金龙及裂叶牵牛中均得到协同性的差异表达,而这些代谢通路指导的产物合成对五爪金龙的抗逆境能力、生长、化感作用等均起关键作用。关键基因的RT-qPCR验证结果与转录组结果具有一致性。因此,这从分子生物学层面上对解释五爪金龙在华南地区的入侵机制提供了新的证据。     

The Ultrastructure of the Fungus Trichoderma viride and Investigation of its Growth on Cellulose

Changes in the ultrastructure of Trichoderma viride during growth in shake cultures on cellobiose and cellulose fibres were examined. Electron micrographs of thin sections of germinating conidia, septate hyphae with ascomycete pores and other cell organelles are presented. Extensive autolysis of hyphae was observed after growth for 20 h on cellobiose. The fungus grew in the lumina and within the walls of cellulose fibres. The hyphae followed the directions of the laminar structure but did not grow across them. The observations indicated that the hyphae penetrated the fibres by causing cracks and by dissolving enzymatically the cellulose.     

Correlations between cresty neck scores and post-mortem nape fat measurements in horses,obtained after photographic image analysis

Background

Obesity and emaciation in horses have major detrimental effects on health and morbidity, reproductive failure, work performance or carcass quality. Scoring is a current management tool used to assess and monitor equine body condition due to its simplicity and low cost. However, accurate assessment of obesity remains a challenge, even though a number of approaches have been tested, particularly for research purposes on adiposity. Their merit is usually validated by comparison with standard scoring methods. The overall aim of this study was to establish the correlation between post-mortem nape fat measurements obtained after photographic image analysis and cresty neck score (CNS) in horses. Data were collected from seventeen horses with a hot carcass weight of 165 ± 51 kg. Pre-slaughter CNS measurements were obtained using a six-point scale (from 0 to 5). Image capture was performed post-mortem, in the slaughter line; for each carcass, images of the dorsal and medial views were collected and afterwards transferred to a computer for analysis. After outlining the cresty neck fat, its area, major axis and thickness were determined. Correlation coefficients between nape fat measurements, CNS and carcass fatness were determined.

Results

The horses in the study show similar variation for CNS and hot carcass weight [Coefficient of variation (CV) = 32 and 31 %, respectively], but a high variation for carcass fattening (CV = 41 %). The nape fat area measurement was the parameter exhibiting the greatest variation (CV = 50 %). Correlations established between CNS and the variables tested revealed the existence of moderate to strong correlations among CNS, nape fat measurements, and carcass fatness. The highest correlation coefficients were found between CNS and nape fat thickness (r = 0.882; P < 0.01). The linear regression between CNS and nape fat thickness accounted for 77 % of the recorded variation for nape fat thickness.

Conclusions

The present study showed that there is a strong correlation between horse CNS and post-mortem nape fat measurements or carcass fatness.