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1.
Sci Rep ; 13(1): 12593, 2023 08 03.
Article in English | MEDLINE | ID: mdl-37537165

ABSTRACT

Sialic acids (Sias) are a class of sugar molecules with a parent nine-carbon neuraminic acid, generally present at the ends of carbohydrate chains, either attached to cellular surfaces or as secreted glycoconjugates. Given their position and structural diversity, Sias modulate a wide variety of biological processes. However, little is known about the role of Sias in human adipose tissue, or their implications for health and disease, particularly among individuals following different dietary patterns. The goal of this study was to measure N-Acetylneuraminic acid (Neu5Ac), N-Glycolylneuraminic acid (Neu5Gc), and 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN) concentrations in adipose tissue samples from participants in the Adventist Health Study-2 (AHS-2) and to compare the abundance of these Sias in individuals following habitual, long-term vegetarian or non-vegetarian dietary patterns. A method was successfully developed for the extraction and detection of Sias in adipose tissue. Sias levels were quantified in 52 vegans, 56 lacto-vegetarians, and 48 non-vegetarians using LC-MS/MS with Neu5Ac-D-1,2,3-13C3 as an internal standard. Dietary groups were compared using linear regression. Vegans and lacto-ovo-vegetarians had significantly higher concentrations of Neu5Ac relative to non-vegetarians. While KDN levels tended to be higher in vegans and lacto-ovo-vegetarians, these differences were not statistically significant. However, KDN levels were significantly inversely associated with body mass index. In contrast, Neu5Gc was not detected in human adipose samples. It is plausible that different Neu5Ac concentrations in adipose tissues of vegetarians, compared to those of non-vegetarians, reflect a difference in the baseline inflammatory status between the two groups. Epidemiologic studies examining levels of Sias in human adipose tissue and other biospecimens will help to further explore their roles in development and progression of inflammatory conditions and chronic diseases.


Subject(s)
Sialic Acids , Sugar Acids , Humans , Sialic Acids/chemistry , Chromatography, Liquid , Sugar Acids/chemistry , Tandem Mass Spectrometry , Adipose Tissue , Diet, Vegetarian
2.
Molecules ; 29(1)2023 Dec 22.
Article in English | MEDLINE | ID: mdl-38202663

ABSTRACT

Phyllanthus acuminatus has been studied for its vast medical and industrial potential. Phytochemical investigations reveal that the genus is a rich source of lignans, flavonoids, phenolics, terpenoids, and other metabolites. However, the phytochemical profile elucidation of this species still needs further research. The use of eliciting compounds such as salicylic acid and methyl jasmonate has managed to increase the production of secondary metabolites in plant cell cultures. Hairy roots of Phyllanthus acuminatus were produced in 250 mL flasks with a 16 h light/8 h darkness photoperiod under diffused light with a culture time of four weeks. The elicitors salicylic acid and methyl jasmonate were tested in 50 µM and 200 µM concentrations. Non-targeted analysis was done for the different treatments using HR-MS. Identified metabolites were grouped in phenylpropanoids, phenols, and mucic acids, and statistical analysis of relative concentrations was achieved. A significant change in phenols' relative concentrations appeared in the elicitations with salicylic acid. Because of the elicitation treatment, specific compounds increased their concentrations, some of which have known pharmacological effects and are used in treating chronic diseases. The best elicitation treatment was salicylic acid 50 µM as it increased by more than 100% the general content of phenols and phenylpropanoid derivates and triplicates the concentration of mucic acid derivates in treated hairy root extracts. The application of non-targeted analysis showed interesting changes in phytochemical concentration due to elicitation in Phyllanthus acuminatus hairy roots.


Subject(s)
Acetates , Cyclopentanes , Oxylipins , Phenols , Phyllanthus , Sugar Acids , Mass Spectrometry , Salicylic Acid/pharmacology , Phytochemicals/pharmacology
3.
Braz J Microbiol ; 52(1): 257-265, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33145708

ABSTRACT

As a key precursor of vitamin C, 2-keto-L-gulonic acid (2-KLG) was mainly produced from L-sorbose by mixed fermentation of Ketogulonicigenium vulgare and a helper strain (Bacillus spp.) with a low conversion rate for decades. The aim of this study was to enhance the 2-KLG production by co-culturing K. vulgare and Bacillus megaterium using three-stage temperature control (TSTC) strategy. By investigating the temperature effect on the 2-KLG fermentation, the optimum temperatures for the growths of K. vulgare and B. megaterium were 32 °C and 29 °C, respectively, while the optimum temperature for 2-KLG production was 35 °C. We developed a TSTC process: the temperature was kept at 32 °C during the first 16 h of fermentation, then decreased to 29 °C for the following 14 h, and maintained at 35 °C to the end of fermentation. By using this new process, the productivity and yield of 2-KLG from L-sorbose were obtained at 2.19 ± 0.19 g/L/h and 92.91 ± 1.02 g/L in 20-L fermentors for 5 batches, respectively, which were 22.35% and 6.02% higher than that of the control treatment (the single temperature of 29 °C). The increased cell density of K. vulgare during the exponential phase and the enhanced SDH activity (increased by 25.18% at 36 h, 17.14% at 44 h) in the production stage might be the reasons for enhanced 2-KLG conversion rate and yield. Our results demonstrated the feasibility of the TSTC strategy for 2-KLG production.


Subject(s)
Bacillus megaterium/metabolism , Bacteriological Techniques , Rhodobacteraceae/metabolism , Sugar Acids/metabolism , Temperature , Bacillus megaterium/growth & development , Bioreactors , Culture Media/chemistry , Fermentation , Rhodobacteraceae/growth & development , Sorbose/metabolism , Sugar Acids/analysis
4.
Braz. j. microbiol ; Braz. j. microbiol;48(3): 397-402, July-Sept. 2017. tab, graf
Article in English | LILACS | ID: biblio-889149

ABSTRACT

Abstract A new plate method was developed for rapid screening of Ketogulonicigenium vulgare mutants overproducing 2-keto-l-gulonic acid (2-KLG). The screening methodology took the advantage of the acidity caused by 2-KLG, which changes the color of bromothymol blue (pH indicator) from blue to yellow. Using the proposed method, a mutant, K. vulgare 65, was selected from 20,000 colonies produced by a strain subjected to spaceflight mutagenesis. When co-cultured with Bacillus megaterium 2980 in 20-L fermenters, K. vulgare 65 showed a high conversion rate (94.45%) of l-sorbose to 2-KLG. In contrast to the traditional screening method, this one significantly improved the frequency of obtaining positive mutants. The proposed plate screening method is cost-effective and easy to run and is thus useful for the isolation and screening of K. vulgare mutants overproducing 2-KLG.


Subject(s)
Sugar Acids/metabolism , Bacteriological Techniques/methods , Rhodobacteraceae/metabolism , Sorbose/metabolism , Bacteriological Techniques/instrumentation , Rhodobacteraceae/isolation & purification , Rhodobacteraceae/genetics , Fermentation , Mutation
5.
Braz J Microbiol ; 48(3): 397-402, 2017.
Article in English | MEDLINE | ID: mdl-28292630

ABSTRACT

A new plate method was developed for rapid screening of Ketogulonicigenium vulgare mutants overproducing 2-keto-l-gulonic acid (2-KLG). The screening methodology took the advantage of the acidity caused by 2-KLG, which changes the color of bromothymol blue (pH indicator) from blue to yellow. Using the proposed method, a mutant, K. vulgare 65, was selected from 20,000 colonies produced by a strain subjected to spaceflight mutagenesis. When co-cultured with Bacillus megaterium 2980 in 20-L fermenters, K. vulgare 65 showed a high conversion rate (94.45%) of l-sorbose to 2-KLG. In contrast to the traditional screening method, this one significantly improved the frequency of obtaining positive mutants. The proposed plate screening method is cost-effective and easy to run and is thus useful for the isolation and screening of K. vulgare mutants overproducing 2-KLG.


Subject(s)
Bacteriological Techniques/methods , Rhodobacteraceae/metabolism , Sugar Acids/metabolism , Bacteriological Techniques/instrumentation , Fermentation , Mutation , Rhodobacteraceae/genetics , Rhodobacteraceae/isolation & purification , Sorbose/metabolism
6.
Plant Physiol Biochem ; 104: 29-35, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27010742

ABSTRACT

Ascorbic acid (AA) is synthesized in plant mitochondria through the oxidation of l-galactono-1,4-lactone (l-GalL) and then distributed to different cell compartments. AA-deficient Arabidopsis thaliana mutants (vtc2) and exogenous applications of l-GalL were used to generate plants with different AA content in their leaves. This experimental approach allows determining specific AA-dependent effects on carbon metabolism. No differences in O2 uptake, malic and citric acid and NADH content suggest that AA synthesis or accumulation did not affect mitochondrial activity; however, l-GalL treatment increased CO2 assimilation and photosynthetic electron transport rate in vtc2 (but not wt) leaves demonstrating a stimulation of photosynthesis after l-GalL treatment. Increased CO2 assimilation correlated with increased leaf stomatal conductance observed in l-GalL-treated vtc2 plants.


Subject(s)
Arabidopsis/physiology , Ascorbic Acid/biosynthesis , Mitochondria/metabolism , Photosynthesis , Arabidopsis/drug effects , Cell Respiration/drug effects , Dehydroascorbic Acid/metabolism , Glutathione/metabolism , Lactones/pharmacology , Mitochondria/drug effects , Photosynthesis/drug effects , Plant Stomata/drug effects , Plant Stomata/physiology , Pyridines/pharmacology , Ribulose-Bisphosphate Carboxylase/metabolism , Sugar Acids/pharmacology
7.
Dental press j. orthod. (Impr.) ; 20(2): 29-34, Mar-Apr/2015. tab, graf
Article in English | LILACS | ID: lil-745854

ABSTRACT

OBJECTIVE: The purpose of this study was to assess the influence of magnification and superimposition of structures on CBCT-generated lateral cephalometric radiographs (LCR) using different segments of the cranium. METHODS: CBCT scans of 10 patients were selected. Four LCR were generated using Dolphin Imaging(r) software: full-face, right side, left side and center of the head. A total of 40 images were imported into Radiocef Studio 2(r), and the angles of the most common cephalometric analyses were traced by the same observer twice and within a 10-day interval. Statistical analyses included intraexaminer agreement and comparison between methods by means of intraclass correlation coefficient (ICC) and Bland-Altman agreement tests. RESULTS: Intraexaminer agreement of the angles assessed by ICC was excellent (> 0.90) for 83% of measurements, good (between 0.75 and 0.90) for 15%, and moderate (between 0.50 and 0.75) for 2% of measurements. The comparison between methods by ICC was excellent for 68% of measurements, good for 26%, and moderate for 6%. Variables presenting wider confidence intervals (> 6o) in the Bland-Altman tests, in intraexaminer assessment, were: mandibular incisor angle, maxillary incisor angle, and occlusal plane angle. And in comparison methods the variables with wider confidence interval were: mandibular incisor, maxillary incisor, GoGn, occlusal plane angle, Frankfort horizontal plane (FHP), and CoA. CONCLUSION: Superimposition of structures seemed to influence the results more than magnification, and neither one of them significantly influenced the measurements. Considerable individual variability may occur, especially for mandibular and maxillary incisors, FHP and occlusal plane. .


OBJETIVO: o objetivo do presente estudo foi avaliar a influência da sobreposição estrutural e da magnificação nas radiografias cefalométricas laterais (RCL) geradas por meio de tomografias computadorizadas de feixe cônico (TCFC), usando diferentes segmentos do crânio. MÉTODOS: foram selecionadas 10 tomografias de pacientes. Quatro RCL foram geradas usando Dolphin Imaging, sendo face total, lado direito, lado esquerdo e o centro da cabeça. Um total de 40 imagens foi importado para o Radiocef Studio, e os ângulos das análises cefalométricas mais comuns foram medidos pelo mesmo observador, duas vezes, em um intervalo de 10 dias. As análises estatísticas incluíram concordância intraexaminador e comparação entre os métodos por meio do coeficiente de correlação intraclasse (ICC) e testes de concordância de Bland-Altman. RESULTADOS: a concordância intraexaminador dos ângulos avaliados pelo ICC foi excelente (> 0,90) para 83% das medições, boa (entre 0,75 e 0,90) para 15%, e moderada (entre 0,50 e 0,75) para 2% das medições. A comparação entre os métodos por ICC foi excelente para 68% das medições, boa para 26% e moderada para 6%. As variáveis que apresentaram intervalos de confiança mais amplos (> 6°) nos testes de Bland-Altman, na avaliação intraexaminador, foram: incisivo superior, incisivo inferior e plano oclusal, enquanto nos métodos de comparação, as variáveis com intervalos de confiança mais amplos foram: incisivo inferior, incisivo superior, GoGn, ângulo do plano oclusal, plano horizontal de Frankfort e CoA. CONCLUSÃO: a sobreposição estrutural pareceu influenciar os resultados mais do que a magnificação, mas os métodos não influenciaram significativamente as medições. Considerável variabilidade individual pode ocorrer especialmente para os incisivos superiores e inferiores, plano horizontal de Frankfort e plano oclusal. .


Subject(s)
DNA Repair , Deoxyguanosine/analogs & derivatives , Escherichia coli Proteins/genetics , Escherichia coli/genetics , Gene Expression Regulation, Bacterial , Mutagenesis/radiation effects , Sugar Acids/metabolism , Biological Assay , DNA Breaks, Double-Stranded , DNA Polymerase beta/genetics , DNA Polymerase beta/metabolism , Deoxyguanosine/chemistry , Deoxyguanosine/metabolism , Escherichia coli Proteins/metabolism , Escherichia coli/metabolism , Escherichia coli/radiation effects , Flap Endonucleases/genetics , Flap Endonucleases/metabolism , Furans/chemistry , Furans/metabolism , Gamma Rays , Mutation , Plasmids , Sugar Acids/chemistry
8.
Acta cir. bras ; Acta cir. bras;26(5): 339-345, Sept.-Oct. 2011. graf, tab
Article in English | LILACS | ID: lil-599634

ABSTRACT

PURPOSE: People consume vegetables without the knowledge of the side effects of the biological and chemical contents and interactions between radiopharmaceuticals and herbal extract. To this end, current study is focused on the effects of broccoli extract on biodistribution of radiolabeled glucoheptonate (99mTc-GH) and radiolabeling of blood components. METHODS: GH was labeled with 99mTc. Quality control studies were done utilizing TLC method. Biodistribution studies were performed on male rats which were treated via gavage with either broccoli extract or SF as control group for 15 days. Blood samples were withdrawn from rats' heart. Radiolabeling of blood constituents performed incubating with GH, SnCl2 and 99m Tc. RESULTS: Radiochemical yield of 99mTc-GH is 98.46±1.48 percent (n=8). Biodistribution studies have shown that according to the control, the treated group with broccoli has approximately 10 times less uptake in kidney. The percentage of the radioactivity ratios of the blood components is found to be same in both groups. CONCLUSIONS: Although there is no considerable effect on the radiolabeling of blood components, there is an outstanding change on the biodistribution studies especially on kidneys. The knowledge of this change on kidney uptake may contribute to reduce the risk of misdiagnosis and/or repetition of the examinations in Nuclear Medicine.


OBJETIVO: As pessoas consomem verduras sem o conhecimento dos efeitos colaterais dos conteúdos biológicos e químicos e interações entre os medicamentos radiofarmacêuticos e os extratos vegetais. Para este fim, o estudo atual é focado sobre os efeitos do extrato de brócolis na biodistribuição do fármaco glucoheptonato (99mTc-GH) e da marcação de componentes do sangue. MÉTODOS: GH foi marcado com 99mTc. Estudos de controle de qualidade foram feitos utilizando o método do TLC. Os estudos de biodistribuição foram realizados em ratos machos que foram tratados por gavagem com um extrato de brócolis ou SF como grupo controle para 15 dias. Amostras de sangue foram retiradas do coração de ratos. Marcação de constituintes sanguíneos realizados incubação com SnCl2 GH e 99mTc. RESULTADOS: Radioquímica rendimento de 99mTc-GH é 98,46 ± 1,48 por cento (n = 8). Os estudos de biodistribuição mostraram que de acordo com o controle, o grupo tratado com brócolis tem aproximadamente 10 vezes menor absorção no rim. O percentual do ratio de radioatividade dos componentes do sangue é encontrado para ser igual nos dois grupos. CONCLUSÕES: Embora não haja nenhum efeito considerável sobre a marcação dos componentes do sangue há uma mudança notável na biodistribuição especialmente nos rins. O conhecimento desta mudança na captação de rim pode contribuir para reduzir o risco de erro diagnóstico e/ou a repetição dos exames de Medicina Nuclear.


Subject(s)
Animals , Male , Rats , Blood Cells/metabolism , Brassica/chemistry , Organotechnetium Compounds/pharmacokinetics , Plant Extracts/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Sugar Acids/pharmacokinetics , Organ Specificity , Organotechnetium Compounds/blood , Plant Extracts/blood , Rats, Wistar , Radiopharmaceuticals/blood , Sugar Acids/blood , Time Factors , Tissue Distribution
9.
Acta Cir Bras ; 26(5): 339-45, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21952655

ABSTRACT

PURPOSE: People consume vegetables without the knowledge of the side effects of the biological and chemical contents and interactions between radiopharmaceuticals and herbal extract. To this end, current study is focused on the effects of broccoli extract on biodistribution of radiolabeled glucoheptonate ((99m)Tc-GH) and radiolabeling of blood components. METHODS: GH was labeled with (99m)Tc. Quality control studies were done utilizing TLC method. Biodistribution studies were performed on male rats which were treated via gavage with either broccoli extract or SF as control group for 15 days. Blood samples were withdrawn from rats' heart. Radiolabeling of blood constituents performed incubating with GH, SnCl2 and (99m) Tc. RESULTS: Radiochemical yield of (99m)Tc-GH is 98.46±1.48 % (n=8). Biodistribution studies have shown that according to the control, the treated group with broccoli has approximately 10 times less uptake in kidney. The percentage of the radioactivity ratios of the blood components is found to be same in both groups. CONCLUSIONS: Although there is no considerable effect on the radiolabeling of blood components, there is an outstanding change on the biodistribution studies especially on kidneys. The knowledge of this change on kidney uptake may contribute to reduce the risk of misdiagnosis and/or repetition of the examinations in Nuclear Medicine.


Subject(s)
Blood Cells/metabolism , Brassica/chemistry , Organotechnetium Compounds/pharmacokinetics , Plant Extracts/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Sugar Acids/pharmacokinetics , Animals , Male , Organ Specificity , Organotechnetium Compounds/blood , Plant Extracts/blood , Radiopharmaceuticals/blood , Rats , Rats, Wistar , Sugar Acids/blood , Time Factors , Tissue Distribution
10.
J Pain ; 12(3): 315-22, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20705523

ABSTRACT

UNLABELLED: We investigated the antinociceptive effects of AR-A014418, a selective inhibitor of glycogen synthase kinase-3ß (GSK-3ß) in mice. A 30-minute pretreatment with AR-A014418 (.1 and 1 mg/kg, intraperitoneal [ip]) inhibited nociception induced by an ip injection of acetic acid. AR-A014418 pretreatment (.1 and .3 mg/kg, ip) also decreased the late (inflammatory) phase of formalin-induced licking, without affecting responses of the first (neurogenic) phase. In a different set of experiments, AR-A014418 (.1-10 µg/site) coinjected intraplantarly (ipl) with formalin inhibited the late phase of formalin-induced nociception. Furthermore, AR-A014418 administration (1 and 10 ng/site, intrathecal [it]) inhibited both phases of formalin-induced licking. In addition, AR-A014418 coinjection (10 ng/site, it) inhibited nociception induced by glutamate, N-methyl-D-aspartate (NMDA), (±)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (trans-ACPD), tumor necrosis factor-alpha (TNF-α), and interleukin-1beta (IL-1ß) by 47 ± 12%, 48 ± 11%, 31 ± 8%, 46 ± 13%, and 44 ± 11%, respectively. In addition, a 30-minute pretreatment with NP031115 (3 and 10 mg/kg, ip), a different GSK-3 ß inhibitor, also attenuated the late phase of formalin-induced nociception. Collectively, these results provide convincing evidence that AR-A014418, given by local, systemic, and central routes, produces antinociception in several mouse models of nociception. The AR-A014418-dependent antinociceptive effects were induced by modulation of the glutamatergic system through metabotropic and ionotropic (NMDA) receptors and the inhibition of the cytokine (TNF-α and IL-1ß) signaling. PERSPECTIVE: These results suggest that GSK-3ß may be a novel pharmacological target for the treatment of pain.


Subject(s)
Abdominal Pain/prevention & control , Analgesics/administration & dosage , Glycogen Synthase Kinase 3/antagonists & inhibitors , Thiazoles/administration & dosage , Urea/analogs & derivatives , Abdominal Pain/chemically induced , Aggression/drug effects , Analysis of Variance , Animals , Anti-Inflammatory Agents, Non-Steroidal , Azides/administration & dosage , Cytokines/administration & dosage , Cytokines/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Administration Routes , Formaldehyde/adverse effects , Glutamic Acid/adverse effects , Inflammation/chemically induced , Inflammation/drug therapy , Male , Mice , N-Methylaspartate/administration & dosage , Pain Measurement/methods , Sugar Acids/adverse effects , Urea/administration & dosage , Xylose/adverse effects , Xylose/analogs & derivatives
11.
Tree Physiol ; 29(4): 607-20, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19203977

ABSTRACT

To help unravel the role of brassinosteroids (BRs) in the control of shooting, we treated the shoots of Marubakaido apple rootstock (Malus prunifolia (Willd.) Borkh cv. Marubakaido) with brassinolide and Brz 220, an inhibitor of BR biosynthesis. Brassinolide differentially affected elongation and formation of main and primary lateral shoots, which resulted in reduced apical dominance. Treatment of shoots with increasing doses of Brz 220 led to a progressive inhibition of main shoot elongation. Eight different BRs were also identified in the shoots of M. prunifolia. Progressive decline in 6-deoxocathasterone, 6-deoxotyphasterol and castasterone was related to increased doses of Brz 220. Analysis of the metabolic profiles between a fluoro-containing derivative of 28-homocastasterone (5F-HCS) using treated and untreated shoots demonstrated that no 5F-HCS-specific metabolite was identified. However, 4 weeks after the treatment, fructose, glucose and the putatively identified gulonic acid were higher in 5F-HCS-treated shoots, compared to untreated shoots. These results indicate that the previously reported 5F-HCS-induced stimulation of shoot elongation and formation of new shoots in the Marubakaido shoots is under the control of changes in the endogenous BR pool. In addition, the results presented in this report also indicate that the 5F-HCS-induced shooting likely involves a variety of different mechanisms and consequently does not result from changes in the endogenous levels of any single metabolite.


Subject(s)
Malus/growth & development , Triazoles/pharmacology , Cholestanones/pharmacology , Dioxoles/pharmacology , Fructose/metabolism , Glucose/metabolism , Malus/drug effects , Malus/metabolism , Plant Growth Regulators/biosynthesis , Plant Shoots/drug effects , Plant Shoots/growth & development , Plant Shoots/metabolism , Steroids/metabolism , Sugar Acids/metabolism , Triazoles/chemistry
12.
Carbohydr Res ; 343(16): 2804-12, 2008 Nov 03.
Article in English | MEDLINE | ID: mdl-18774555

ABSTRACT

The reactivity of N-(2-aminophenyl)-d-glycero-d-gulo-heptonamide (adgha), with the group 12 cations, Zn(II), Cd(II), and Hg(II), was studied in DMSO-d(6) solution. The studied system showed a selective coordination to Hg(II), and the products formed were characterized by (1)H and (13)C NMR in DMSO-d(6) solution and fast atom bombardment (FAB(+)) mass spectra. The expected coordination compounds, [Hg(adgha)](NO(3))(2) and [Hg(adgha)(2)](NO(3))(2), were observed as unstable intermediates that decompose to bis-[2-(d-glycero-d-gulo-hexahydroxyhexyl)-benzimidazole-κN]mercury(II) dinitrate, [Hg(ghbz)(2)](NO(3))(2). The chemical transformation of the complexes was followed by NMR experiments, and the nature of the species formed is sustained by a theoretical study done using DFT methodology. From this study, we propose the structure of the complexes formed in solution, the relative stability of the species formed, and the possible role of the solvent in the observed transformations.


Subject(s)
Anilides/chemistry , Mercury/chemistry , Organometallic Compounds/chemistry , Quantum Theory , Sugar Acids/chemistry , Ions/chemistry , Models, Molecular , Organometallic Compounds/chemical synthesis , Thermodynamics
13.
Interciencia ; Interciencia;32(5): 328-332, mayo 2007. tab, graf
Article in English | LILACS | ID: lil-493131

ABSTRACT

Para la producción fermentativa de ácido láctico se evaluaron como sustrato residuos de cosecha de caña de azúcar (variedad CC85-92). Las fermentaciones se realizaron a 32ºC y pH 6,0, utilizando jugos obtenidos de hojas y cogollos (JTL), y Lactococcus lactis subs. lactis aislado de caña de azúcar de la misma variedad. En las fermentaciones se midieron la concentración de ácido láctico (LA), la conversión de sustrato (SC), la concentración de biomasa, la velocidad de formación de producto (rp) y el rendimiento (Yp/s), y los resultaron se compararon con fermentaciones que utilizaron la misma cepa y medio de cultivo comercial MRS adicionado de glucosa hasta 60g.l-¹. Utilizando JTL se pueden obtener concentraciones de ácido láctico por encima de 28,5g.l-¹ y rendimientos de 0,85g. g-¹ en 48 horas de fermentación. Los sustratos JTL y MRS mostraron diferencias estadísticamente significativas en Yp/s, SC y concentración de biomasa, y diferencias estadísticamente no significativas en LA y rp. Los resultados sugieren que los residuos de cosecha de caña de azúcar pueden ser utilizados como materia prima barata para la producción fermentativa de ácido láctico.


Subject(s)
Sugar Acids/analysis , Fermentation , Saccharum , Colombia , Microbiology
14.
J Appl Microbiol ; 102(1): 77-88, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17184322

ABSTRACT

AIM: To evaluate the genetic and molecular diversity and insecticidal activity of Bacillus thuringiensis isolates from all the natural regions of Colombia. METHODS AND RESULTS: A total of 445 isolates from a collection of B. thuringiensis were characterized. The parasporal crystal morphology that was most abundant was bipyramidal (60%). Almost 10% of the isolates were toxic to Spodoptera frugiperda and 5.6% against Culex quinquefasciatus larvae. cry gene content determined by PCR indicated that 10.6% of the isolates contained cry1 genes and 1.1% contained cry2, cry4 or cry11 genes. Protein content of the parasporal crystal was determined by SDS-PAGE; 25 and 18 different protein profiles were found in isolates active against S. frugiperda and C. quinquefasciatus, respectively. CONCLUSIONS: Bacillus thuringiensis presents great genetic and molecular diversity even in isolates from the same soil sample. Moreover, the diversity and activity of the isolates might have a relationship with the geographical origin of the samples. SIGNIFICANCE AND IMPACT OF THE STUDY: The results obtained here indicate that some of the B. thuringiensis isolates characterized in this study are potential control agents that could be used in programmes against mosquitoes and S. frugiperda.


Subject(s)
Bacillus thuringiensis/genetics , Diptera/microbiology , Lepidoptera/microbiology , Adenosine/analogs & derivatives , Adenosine/biosynthesis , Animals , Bacterial Proteins/analysis , Bacterial Toxins/biosynthesis , Biodiversity , Colombia , Cryptochromes , Culex/microbiology , Electrophoresis, Polyacrylamide Gel/methods , Flavoproteins/genetics , Genes, Bacterial/genetics , Insecticides , Larva/microbiology , Polymerase Chain Reaction/methods , Spodoptera/microbiology , Sugar Acids
15.
Carbohydr Res ; 341(18): 2973-7, 2006 Dec 29.
Article in English | MEDLINE | ID: mdl-17097075

ABSTRACT

2,3,4,6-Tetra-O-methyl-d-galactonic acid (5) was readily prepared from d-galactono-1,4-lactone (1) in 47% yield. The sequence involves tritylation of HO-6 of 1, followed by O-permethylation and deprotection. Lactonization of 5 led to the per-O-methyl-d-galactono-1,6-lactone, which was copolymerized with epsilon-caprolactone by ring-opening polymerization catalyzed by scandium triflate. The incorporation of the sugar comonomer into the polyester chain was about 10%.


Subject(s)
Sugar Acids/chemistry , Caproates/chemistry , Lactones/chemistry , Polyesters/chemical synthesis , Sugar Acids/chemical synthesis
16.
Carbohydr Res ; 341(11): 1788-95, 2006 Aug 14.
Article in English | MEDLINE | ID: mdl-16696960

ABSTRACT

A photoinduced electron-transfer (PET) reaction was used for the deoxygenation at C-2 of aldonolactones derivatized as 2-O-[3-(trifluoromethyl)benzoyl] or benzoyl esters. By irradiation of different D-galactono- and D-glucono-1,4-derivatives, with a 450W lamp, using 9-methylcarbazole as photosensitizer, the corresponding 2-deoxy-D-lyxo- and 2-deoxy-D-arabino-hexono-1,4-lactones were efficiently obtained.


Subject(s)
Glucuronates/chemical synthesis , Lactones/chemical synthesis , Sugar Acids/chemical synthesis , Deoxy Sugars/chemical synthesis , Deoxy Sugars/chemistry , Electron Transport , Glucuronates/chemistry , Lactones/chemistry , Magnetic Resonance Spectroscopy , Molecular Structure , Monosaccharides/chemistry , Photochemistry/methods , Sugar Acids/chemistry
17.
Carbohydr Res ; 341(10): 1498-504, 2006 Jul 24.
Article in English | MEDLINE | ID: mdl-16618479

ABSTRACT

2-Amino-2,3-dideoxy-D-manno-heptonic acid (7) has been synthesized from 2,5,6,7-tetra-O-acetyl-3-deoxy-D-gluco-heptono-1,4-lactone (1), which was readily prepared from D-glycero-D-gulo-heptono-1,4-lactone. O-Deacetylation of 1 followed by treatment with 13:1 (v/v) 2,2-dimethoxypropane/acetone in the presence of p-toluenesulfonic acid gave methyl 3-deoxy-4,5:6,7-di-O-isopropylidene-D-gluco-heptonate (3) as a crystalline product (80% yield). The free hydroxyl group (OH-2) of 3 was mesylated and substituted by azide to give the corresponding azide derivative 5. Hydrogenolysis and further hydrolysis of the ester function of 5 afforded alpha-amino acid 7 (43% overall yield from 1). Compound 7 is an analog of L-alanine having a polyhydroxy chain attached to C-3. The diastereoisomer of 7 at C-2, 2-amino-2,3-dideoxy-D-gluco-heptonic acid (12) was also prepared from 3, by a route that involved 2,3-dideoxy-2-iodo derivative 8 as a key intermediate.


Subject(s)
Alanine/chemistry , Amino Sugars/chemical synthesis , Heptoses/chemistry , Sugar Acids/chemical synthesis , Carbohydrate Conformation , Stereoisomerism
19.
J Invertebr Pathol ; 86(1-2): 7-18, 2004.
Article in English | MEDLINE | ID: mdl-15145246

ABSTRACT

Bacillus thuringiensis strains C-4, C-9, GM-7, and GM-10, isolated from northeast Mexico and selected for their high toxicity against lepidopteran and coleopteran pests, were characterized following United States Environmental Protection Agency (EPA)'s guidelines. Flagellar serotyping revealed that GM-7 and GM-10 belonged to serotype aizawai, whereas C-4, C-9 corresponded to the kumamotoensis serotype. GM-10 and C-9 were also shown to be the most effective against lepidoptera and coleoptera larvae, respectively. None of the tested strains produced beta-exotoxin or showed activity against mosquitoes. GM-7 and GM-10 were sensitive to R-41 and CP-51 phages. All strains synthesized crystal proteins of 130-140 kDa. PCR analysis showed that C-4, GM-7, and GM-10 strains expressed cry1 genes, and C-9 expressed cry3 and cry7/8 genes, but not cry1. However, the C-9 strain had no cross-reaction with antisera raised against Cry3A and Cry7A proteins. GM-7 and GM-10 were sensitive to R-41 and CP-51 phages. When the delta-endotoxin (crystal) from the four strains was subcutaneously injected to Balb/c mice, alone or in combination with spores, only C-4 and C-9 provoked tissue necrosis similar to that caused by the beta-exotoxin producer HD-41. Tissue necrosis was prevented with the injection of pentoxifylline, an inhibitor of tumor necrosis factor alpha (TNF-alpha) production, suggesting a role of this cytokine in the observed effect. Our results demonstrated that GM-7 and GM-10 strains are effective and suitable for control of lepidopteran pests and safe for mammals under EPA regulations. The potential of the C-9 strain for the control of several coleopteran pests, and the induction of tissue necrosis in mice by C-4 and C-9 strains, are discussed.


Subject(s)
Adenosine/analogs & derivatives , Bacillus thuringiensis/physiology , Bacterial Toxins , Coleoptera/parasitology , Larva/parasitology , Lepidoptera/parasitology , Pest Control, Biological/methods , Adenosine/biosynthesis , Animals , Bacillaceae Infections/pathology , Bacillus thuringiensis/classification , Bacillus thuringiensis Toxins , Bacterial Proteins/genetics , Bacterial Proteins/toxicity , Blotting, Western , Endotoxins/genetics , Endotoxins/toxicity , Female , Hemolysin Proteins , Mice , Polymerase Chain Reaction , Serotyping , Skin/drug effects , Skin/pathology , Sugar Acids
20.
Phytochemistry ; 62(8): 1265-70, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12648549

ABSTRACT

2-Deoxyribonolactones and four tetrahydroisoquinoline alkaloids were isolated from the acetone extract of the leaves of Aristolochia arcuata Mast., together with pinitol, sequoyitol, glycerol, fructose, sucrose, eupomatenoid-7, salsolinol, and 6,7-dihydroxy-1,1-dimethyl-1,2,3,4-tetrahydroisoquinoline. Their structures were determined on the basis of spectroscopic methods, mainly using 1H, 13C, 15N, and 31P NMR.


Subject(s)
Alkaloids/chemistry , Aristolochia/chemistry , Isoquinolines/chemistry , Lactones/chemistry , Alkaloids/isolation & purification , Chromatography, Liquid/methods , Isoquinolines/isolation & purification , Lactones/isolation & purification , Nuclear Magnetic Resonance, Biomolecular/methods , Plant Leaves/chemistry , Spectrometry, Mass, Electrospray Ionization , Spectroscopy, Fourier Transform Infrared , Sugar Acids/chemistry
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