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1.
J Alzheimers Dis ; 95(4): 1559-1572, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37718811

RESUMO

BACKGROUND: Accurate epidemiological data on mild cognitive impairment (MCI) and Alzheimer's disease (AD) can inform the development of prevention and control measures, but there is a lack of such data in Japan. OBJECTIVE: To investigate the disease burden and progression in patients with new-onset MCI or AD in Japan. METHODS: Using claims data, this multi-region cohort study was conducted on new-onset MCI and AD patients in 17 municipalities from 2014 to 2021. To characterize the patients, we investigated their age, comorbidities, and long-term care (LTC) needs levels at disease onset according to region type (urban, suburban, or rural). Disease burden was examined using health care expenditures and LTC expenditures, which were estimated for 1, 2, and 3 years after disease onset. Kaplan-Meier curves were plotted for AD progression in new-onset MCI patients and death in new-onset AD patients. RESULTS: We analyzed 3,391 MCI patients and 58,922 AD patients. In MCI and AD patients, health care expenditures were high in the first year ($13,035 and $15,858, respectively), but had declined by the third year ($8,278 and $10,414, respectively). In contrast, LTC expenditures (daily living support) steadily increased over the 3-year period (MCI patients: $1,767 to $3,712, AD patients: $6,932 to $9,484). In the third year after disease onset, 30.9% of MCI patients developed AD and 23.3% of AD patients had died. CONCLUSIONS: This provides an important first look at the disease burden and progression of MCI and AD in Japan, which are high-priority diseases for a rapidly aging population.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/psicologia , Estudos de Coortes , População do Leste Asiático , Progressão da Doença , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/psicologia , Efeitos Psicossociais da Doença
2.
J Pestic Sci ; 46(1): 115-119, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33746553

RESUMO

Three novel analogs of pochonicine (1) were isolated from a solid fermentation culture of the fungal strain Pochonia suchlasporia var. suchlasporia TAMA 87, and their structures were elucidated as 7-deoxypochonicine (2), 6-deoxypochonicine (3), and 6,7-dideoxypochonicine (4). These analogs were found to possess the same stereochemistry as pochonicine. Comparison of ß-N-acetylglucosaminidase (GlcNAcase) inhibitory activity between these analogs and pochonicine suggested that the C-6 hydroxy group of pochonicine was essential to its potent GlcNAcase inhibitory activity and that the C-7 hydroxy group also contributed to the activity, but to a lesser extent than the C-6 hydroxy group.

3.
Biosci Biotechnol Biochem ; 85(4): 989-997, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33710320

RESUMO

Norathyriol is an aglycone of a xanthonoid C-glycoside mangiferin that possesses different bioactive properties useful for humans compared to mangiferin. Mangiferin is more readily available in nature than norathyriol; thus, efficient mangiferin conversion into norathyriol is desirable. There are a few reports regarding mangiferin C-deglycosylation because of the C-C bond resistance toward acid, alkaline, and enzyme hydrolysis. In this study, we isolated a mangiferin-deglycosylating bacterium strain KM7-1 from the mouse intestine. 16S rDNA sequencing indicated that KM7-1 belongs to the Bacillus genus. Compared to the taxonomically similar bacteria, the growth characteristic of facultative anaerobic and thermophilic resembled, yet only Bacillus sp. KM7-1 was able to convert mangiferin into norathyriol. Resting cells of Bacillus sp. KM7-1 obtained from aerobic cultivation at 50 °C showed high norathyriol formation from 1 m m of mangiferin. Norathyriol formation can be conducted either under aerobic or anaerobic conditions, and the reaction depended on time and bacterial amount.


Assuntos
Glicosídeos/metabolismo , Xantonas/metabolismo , Aerobiose , Animais , Bacillus/genética , Bacillus/metabolismo , DNA Ribossômico/genética , Camundongos , RNA Ribossômico 16S/genética
4.
J Pestic Sci ; 45(2): 81-85, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32508514

RESUMO

A new asteltoxin analog, named asteltoxin H (1), was isolated by the solid-state fermentation of the fungus Pochonia suchlasporia var. suchlasporia TAMA 87. The chemical structure of 1 was deduced by spectroscopic methods, including 1D and 2D NMR, HRESIMS, and UV-Vis analyses. Compound 1 showed insecticidal activity against prepupae of the blowfly, Lucilia sericata, with an LD50 value of 0.94 µg/mg prepupal body weight.

5.
J Biosci Bioeng ; 129(2): 150-154, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31492608

RESUMO

A tannase-encoding gene, AotanB, from Aspergillus oryzae RIB40 was overexpressed in A. oryzae AOK11 niaD-deficient mutant derived from an industrial strain under the control of an improved glucoamylase gene promoter PglaA142. The recombinant tannase, designated as rAoTanBO, was produced efficiently as an active extracellular enzyme. Purified rAoTanBO showed a smeared band with a molecular mass of approximately 80-100 kDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The rAoTanBO had a molecular mass of 65 kDa, after treatment with endo-ß-N-acetylglucosaminidase H. Purified rAoTanBO exhibited maximum activity at 30-35°C and pH 6.0. The tannase activity of purified rAoTanBO towards natural and artificial substrates was 2-8 folds higher than that of the recombinant enzyme produced by Pichia pastoris, designated as rAoTanBP. N-terminus of the mature rAoTanBP had six more amino acids than the N-terminus of the mature rAoTanBO. Kinetic analyses showed that rAoTanBO had higher catalytic efficiency (kcat/Km) than rAoTanBP. rAoTanBO was stable up to 60°C and higher thermostability than rAoTanBP. N-linked oligosaccharides had no effect on the activity and stability of rAoTanBO and rAoTanBP.


Assuntos
Aspergillus oryzae/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Glucana 1,4-alfa-Glucosidase/genética , Regiões Promotoras Genéticas , Aspergillus oryzae/genética , Biocatálise , Hidrolases de Éster Carboxílico/genética , Eletroforese em Gel de Poliacrilamida , Cinética , Peso Molecular , Pichia/genética , Pichia/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
6.
J Nat Prod ; 81(10): 2244-2250, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30350994

RESUMO

Biotransformation of ß-mangostin (1) by the endophytic fungus Xylaria feejeensis GM06 afforded hexacyclic ring-fused xanthenes with an unprecedented hexacyclic heterocylic skeleton. ß-Mangostin (1) was transformed to two diastereomeric pairs of enantiomers, mangostafeejin A [(-)-2a/(+)-2b)] and mangostafeejin B [(-)-3a/(+)-3b)]. The chemical structures of the transformation products were elucidated by analysis of NMR and MS data, and the structure of mangostafeejin A [(-)-2a/(+)-2b)] was confirmed by single-crystal X-ray diffraction analysis. The absolute configurations of 3a and 3b were established on the basis of calculated and measured ECD data using the ECD spectra of 2a and 2b as models. The fungal biotransformation described herein provides an effective method to convert an abundant achiral plant natural product scaffold into new chiral heterocyclic scaffolds representing expanded chemical diversity for biological activity screening.


Assuntos
Ácidos Heterocíclicos/síntese química , Garcinia mangostana/microbiologia , Xantenos/síntese química , Xantonas/metabolismo , Xylariales/metabolismo , Biotransformação , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Estereoisomerismo , Difração de Raios X
7.
Saudi J Biol Sci ; 25(4): 642-650, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29740228

RESUMO

This study aimed to produce inexpensive 5-aminolevulinic acid (ALA) in a non-sterile latex rubber sheet wastewater (RSW) by Rhodopseudomonas palustris TN114 and PP803 for the possibility to use in agricultural purposes by investigating the optimum conditions, and applying of wood vinegar (WV) as an economical source of levulinic acid to enhance ALA content. The Box-Behnken Design experiment was conducted under microaerobic-light conditions for 96 h with TN114, PP803 and their mixed culture (1:1) by varying initial pH, inoculum size (% v/v) and initial chemical oxygen demand (COD, mg/L). Results showed that the optimal condition (pH, % inoculum size, COD) of each set to produce extracellular ALA was found at 7.50, 6.00, 2000 for TN114; 7.50, 7.00, 3000 for PP803; and 7.50, 6.00, 4000 for a mixed culture; and each set achieved COD reduction as high as 63%, 71% and 75%, respectively. Addition of the optimal concentration of WV at mid log phase at 0.63% for TN114, and 1.25% for PP803 and the mixed culture significantly increased the ALA content by 3.7-4.2 times (128, 90 and 131 µM, respectively) compared to their controls. ALA production cost could be reduced approximately 31 times with WV on the basis of the amount of levulinic acid used. Effluent containing ALA for using in agriculture could be achieved by treating the RSW with the selected ALA producer R. palustris strains under the optimized condition with a little WV additive.

8.
Biosci Biotechnol Biochem ; 82(3): 422-424, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29375031

RESUMO

A co-cultivation study of two fungal strains showed that Aspergillus ustus could inhibit Aspergillus repens growth. The bioactive compound responsible for the observed activity was purified and identified as a sesterterpene, ophiobolin K. Ophiobolin K exhibited marked inhibition against both fungi and bacteria, especially A. repens, A. glaucus and gram-positive bacteria including Bacillus subtilis, Staphylococcus aureus, and Micrococcus luteus.


Assuntos
Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Aspergillus/metabolismo , Sesterterpenos/biossíntese , Sesterterpenos/farmacologia , Testes de Sensibilidade Microbiana
9.
Molecules ; 22(7)2017 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-28698478

RESUMO

In our continuing study on a survey of biologically active natural products from heartwood of Santalum album (Southwest Indian origin), we newly found potent fish toxic activity of an n-hexane soluble extract upon primary screening using killifish (medaka) and characterized α-santalol and ß-santalol as the active components. The toxicity (median tolerance limit (TLm) after 24 h at 1.9 ppm) of α-santalol was comparable with that of a positive control, inulavosin (TLm after 24 h at 1.3 ppm). These fish toxic compounds including inulavosin were also found to show a significant antifungal effect against a dermatophytic fungus, Trichophyton rubrum. Based on a similarity of the morphological change of the immobilized Trichophyton hyphae in scanning electron micrographs between treatments with α-santalol and griseofulvin (used as the positive control), inhibitory effect of α-santalol on mitosis (the antifungal mechanism proposed for griseofulvin) was assessed using sea urchin embryos. As a result, α-santalol was revealed to be a potent antimitotic agent induced by interference with microtubule assembly. These data suggested that α-santalol or sandalwood oil would be promising to further practically investigate as therapeutic agent for cancers as well as fungal skin infections.


Assuntos
Antimitóticos/farmacologia , Óleos de Plantas/farmacologia , Sesquiterpenos/farmacologia , Animais , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Antimitóticos/química , Divisão Celular/efeitos dos fármacos , Flavonoides/farmacologia , Flavonoides/toxicidade , Fundulidae/genética , Fundulidae/crescimento & desenvolvimento , Óleos de Plantas/química , Sesquiterpenos Policíclicos , Santalum/química , Sesquiterpenos/química , Sesquiterpenos/toxicidade
10.
Carbohydr Polym ; 115: 334-41, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25439902

RESUMO

Removal of Na(+) by binding with exopolymeric substances (EPS) from Rhodopseudomonas palustris TN114 and PP803 was investigated. The moderate negative correlation pairs (rp) between remaining Alcian blue and amount of Na(+) adsorbed on EPS from strains TN114 and PP803 were -0.652 and -0.609. Both strains showed positive relationships between the amounts of EPS produced and bacterial growth. EPS from strain PP803 had a higher efficiency in removing Na(+) than the EPS from strain TN114 based on their EC50 values (1.79 and 1.49 mg/mL for TN114 and PP803, respectively). The principal component from EPS of strain PP803 which was responsible for salt removal was purified and it was identified as a polysaccharide (≈18 kDa) mainly composed of galacturonic acid. Overall results suggested that EPS is a key factor that our strains used to bind Na(+) allowing their survival in high NaCl concentrations.


Assuntos
Biopolímeros/química , Rodopseudomonas/química , Cloreto de Sódio/química , Adsorção , Rodopseudomonas/efeitos dos fármacos , Rodopseudomonas/fisiologia , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos
11.
Electron. j. biotechnol ; 17(1): 4-4, Jan. 2014. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-706518

RESUMO

Background: Rice is globally one of the most important food crops, and NaCl stress is a key factor reducing rice yield. Amelioration of NaCl stress was assessed by determining the growth of rice seedlings treated with culture supernatants containing 5-aminolevulinic acid (ALA) secreted by strains of Rhodopseudomonas palustris (TN114 and PP803) and compared to the effects of synthetic ALA (positive control) and no ALA content (negative control). Results: The relative root growth of rice seedlings was determined under NaCl stress (50 mM NaCl), after 21 d of pretreatment. Pretreatments with 1 μM commercial ALA and 10X diluted culture supernatant of strain TN114 (2.57 μM ALA) gave significantly better growth than 10X diluted PP803 supernatant (2.11 μM ALA). Rice growth measured by dry weight under NaCl stress ordered the pretreatments as: commercial ALA N TN114 N PP803 N negative control. NaCl stress strongly decreased total chlorophyll of the plants that correlated with non-photochemical quenching of fluorescence (NPQ). The salt stress also strongly increased hydrogen peroxide (H2O2) concentration in NaCl-stressed plants. The pretreatments were ordered by reduction in H2O2 content under NaCl stress as: commercial ALA N TN114 N PP803 N negative control. The ALA pretreatments incurred remarkable increases of total chlorophyll and antioxidative activities of catalase (CAT), ascorbate peroxide (APx), glutathione reductase (GR) and superoxide dismutase (SOD); under NaCl stress commercial ALA and TN114 had generally stronger effects than PP803. Conclusions: The strain TN114 has potential as a plant growth stimulating bacterium that might enhance rice growth in saline paddy fields at a lower cost than commercial ALA.


Assuntos
Rodopseudomonas , Oryza/crescimento & desenvolvimento , Oryza/enzimologia , Ácido Aminolevulínico/metabolismo , Antioxidantes , Fotossíntese , Estresse Fisiológico , Superóxido Dismutase/metabolismo , Catalase/metabolismo , Clorofila/análise , Produtos Agrícolas , Plântula , Transporte de Elétrons , Salinidade , Ascorbato Peroxidases/metabolismo , Fluorescência , Glutationa Redutase/metabolismo
12.
Carbohydr Res ; 375: 29-34, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23685037

RESUMO

TMG-chitotriomycin (1) produced by the actinomycete Streptomyces annulatus NBRC13369 was examined as a probe for the prediction of substrate specificity of ß-N-acetylhexosaminidases (HexNAcases). According to the results of inhibition assays, 14 GH20 HexNAcases from various organisms were divided into 1-sensitive and 1-insensitive enzymes. Three representatives of each group were investigated for their substrate specificity. The 1-sensitive HexNAcases hydrolyzed N-acetylchitooligosaccharides but not N-glycan-type oligosaccharides, whereas the 1-insensitive enzymes hydrolyzed N-glycan-type oligosaccharides but not N-acetylchitooligosaccharides, indicating that TMG-chitotriomycin can be used as a molecular probe to distinguish between chitin-degrading HexNAcases and glycoconjugate-processing HexNAcases.


Assuntos
Inibidores Enzimáticos/farmacologia , Sondas Moleculares/farmacologia , Álcoois Açúcares/farmacologia , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , Configuração de Carboidratos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Sondas Moleculares/química , Relação Estrutura-Atividade , Especificidade por Substrato/efeitos dos fármacos , Álcoois Açúcares/química , beta-N-Acetil-Hexosaminidases/isolamento & purificação , beta-N-Acetil-Hexosaminidases/metabolismo
13.
Electron. j. biotechnol ; 15(6): 7-7, Nov. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-662205

RESUMO

The aims were to explore an appropriate isolating medium for obtaining purple nonsulfur bacteria (PNSB) for use as biofertilizers in saline paddy fields and to obtain pure cultures. We therefore chose a defined isolating medium containing 0.25 percent NaCl, (Glutamate-Acetate broth, GA) and a rice straw broth to compare them for numbers of PNSB obtained, time to obtain pure cultures, diversity and costs. A total of 30 water and 30 sediment samples were collected from saline paddy fields in southern Thailand and used to isolate PNSB in both the isolating media. Based on 60 samples and a period of 13 days incubation under anaerobic light conditions, a greater number of samples produced PNSB growth in GA broth after only day 3; however, after that the rice straw broth provided about a 2 fold increase in the number of samples that produced PNSB growth. Colonies isolated from GA broth required a significantly higher number of repeated streaking to obtain a pure culture (average 3.5) than those from rice straw broth (average 2.7) and the latter medium also produced significantly (P < 0.05) more isolates per sample. Sixty samples of water and sediment, from rice paddies with salinity (average, 3.43 +/- 0.67 mS/cm) and slight acidity (average, pH 5.84 +/- 0.42) provided 62 PNSB isolates by GA broth and 210 isolates by rice straw broth, and rice straw broth also produced a greater prevalence of PNSB. Estimates of the costs based on current prices of media, Gas Pak and electricity to obtain PNSB with the use of GA broth was roughly 6 times higher than for the rice straw broth.


Assuntos
Meios de Cultura , Fertilizantes , Oryza , Rhodospirillaceae/isolamento & purificação , Bactérias/isolamento & purificação
14.
Org Biomol Chem ; 9(8): 2943-51, 2011 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-21373681

RESUMO

The reducing tetrasaccharide TMG-chitotriomycin (1) is an inhibitor of ß-N-acetylglucosaminidase (GlcNAcase), produced by the actinomycete Streptomyces anulatus NBRC13369. The inhibitor shows a unique inhibitory spectrum, that is, selectivity toward enzymes from chitin-containing organisms such as insects and fungi. Nevertheless, its structure-selectivity relationship remains to be clarified. In this study, we conducted a structure-guided search of analogues of 1 in order to obtain diverse N,N,N-trimethylglucosaminium (TMG)-containing chitooligosaccharides. In this approach, the specific fragmentation profile of 1 on ESI-MS/MS analysis was used for the selective detection of desired compounds. As a result, two new analogues, named TMG-chitomonomycin (3) and TMG-chitobiomycin (2), were obtained from a culture filtrate of 1-producing Streptomyces. Their enzyme-inhibiting activity revealed that the potency and selectivity depended on the degree of polymerization of the reducing end GlcNAc units. Furthermore, a computational modeling study inspired the inhibitory mechanism of TMG-related compounds as a mimic of the substrate in the Michaelis complex of the GH20 enzyme. This study is an example of the successful application of a MS/MS experiment for structure-guided isolation of natural products.


Assuntos
Acetilglucosaminidase/antagonistas & inibidores , Inibidores Enzimáticos/química , Glucosamina/análogos & derivados , Oligomicinas/química , Acetilglucosaminidase/química , Aspergillus oryzae/efeitos dos fármacos , Aspergillus oryzae/enzimologia , Inibidores Enzimáticos/farmacologia , Glucosamina/química , Modelos Moleculares , Estrutura Molecular , Estrutura Terciária de Proteína , Espectrometria de Massas por Ionização por Electrospray , Streptomyces coelicolor/efeitos dos fármacos , Streptomyces coelicolor/enzimologia , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem
15.
Phytochemistry ; 72(8): 730-4, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21377704

RESUMO

α-Mangostin (1), a prenylated xanthone isolated from the fruit hull of Garcinia mangostana L., was individually metabolized by two fungi, Colletotrichum gloeosporioides (EYL131) and Neosartorya spathulata (EYR042), repectively. Incubation of 1 with C. gloeosporioides (EYL131) gave four metabolites which were identified as mangostin 3-sulfate (2), mangostanin 6-sulfate (3), 17,18-dihydroxymangostanin 6-sulfate (4)and isomangostanin 3-sulfate (5). Compound 2 was also formed by incubation with N. spathulata (EYR042). The structures of the isolated compounds were elucidated by spectroscopic data analysis. Of the isolated metabolites, 2 exhibited significant anti-mycobacterial activity against Mycobacterium tuberculosis.


Assuntos
Antibacterianos/metabolismo , Garcinia mangostana/química , Xantonas/química , Xantonas/metabolismo , Antibacterianos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Estereoisomerismo , Xantonas/isolamento & purificação
16.
Electron. j. biotechnol ; 13(5): 2-3, Sept. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-591884

RESUMO

Lactobacillus plantarum DW3 produced antifungal compounds that inhibited the growth of Rhodotorula mucilaginosa DKA, contaminating yeast in fermented plant beverages (FPBs) and various potential human pathogens. Phenyllactic acid (PLA) identified by gas chromatography- mass spectrometry (GC-MS) was produced at 31 mg/L PLA in MRS medium and 5 mg/ml inhibited growth of the target yeast in vitro by 90 percent. Other inhibitors were also present but not specifically identified. Results of in vitro tests showed that DW3 also had probiotic properties as it survived various human biological barriers resistance to pH 3, bile salts, growth without vitamin B12 and the presence and absence of oxygen. Its inhibitory effect against food borne pathogenic bacteria and spoilage organisms was higher than that found for a commercial strain Lactobacillus casei R. An acute oral toxicity test on ICR mice at a high single dose of either 10(9) and 10(12) cells per mouse for 14 days showed that DW3 had no adverse effect on the general health status and there was no evidence of bacteremia. Mice fed DW3 had a reduced weight gain compared to the control. No significant difference (p > 0.05) was found for the spleen weight index (SWI) among the treatment and control groups whereas there was a significant difference (p < 0.05) for the liver weight ratio (LWR) in a group fed with 10(12) cells per mouse when compared with the control group.


Assuntos
Animais , Camundongos , Antifúngicos/farmacologia , Bebidas/microbiologia , Lactobacillus plantarum/química , Rhodotorula , Antifúngicos/química , Cromatografia Líquida de Alta Pressão , Fermentação , Microbiologia de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Ácido Láctico , Probióticos/química
17.
Electron. j. biotechnol ; 13(1): 8-9, Jan. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-559591

RESUMO

Pseudomonas sp. W3, a bacterium known to produce an extracellular alkaline protease, secreted secondary metabolites that inhibited pathogenic bacteria responsible for shrimp luminous vibriosis disease. Antivibrio compounds in the culture supernatant or culture filtrates (0.45 um and 0.22 um) of the isolate W3 were tested using an agar well diffusion method on a number of pathogenic vibrios. Vibrio harveyi PSU 2015 a pathogenic isolate was the most sensitive strain. The effectiveness of preparations from the isolate W3 against V. harveyi PSU 2015, and V. cholerae PSSCMI 0062 was in the order of culture supernatant > 0.45 um culture filtrate > 0.22 um culture filtrate. These extracellular antivibrio compounds also lysed both dead and living cells of V. harveyi PSU 2015. Results of the partial characterization tests indicated that there was some particulate antivibrio compound that was destroyed by treatment with enzymes particularly alpha-chymotrypsin, autoclaving at 121ºC for 15 min and was mostly removed by filtration through a 0.22 µm filter. Most of the inhibitory compounds were of small molecular weight able to pass through a 0.22 um filter and were resistant to treatment with various enzymes, pH values between 4-8 and temperatures up to 121ºC for 30 min. The optimum pH for the antivibrio activity in the 0.45 um culture filtrate was between pH 6-7.


Assuntos
Animais , Decápodes , Decápodes , Decápodes/metabolismo , Decápodes/microbiologia , Pseudomonas , Pseudomonas/metabolismo , Vibrioses/microbiologia , Vibrioses/tratamento farmacológico , Cloranfenicol/uso terapêutico , Furazolidona/uso terapêutico , Técnicas de Cultura/métodos
18.
Bioorg Med Chem ; 17(20): 7248-53, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19775896

RESUMO

A new polyhydroxylated pyrrolizidine alkaloid designated as pochonicine (1) was isolated from a solid fermentation culture of the fungal strain Pochonia suchlasporia var. suchlasporia TAMA 87. The structure of 1 was determined using NMR and MS techniques as (1R*, 3S*, 5S*, 6S*, 7R*, 7a S*)-5-acetamidomethyl-3-hydroxymethyl-1,6,7-trihydroxypyrrolizidine. Pochonicine (1) showed potent inhibition against beta-N-acetylglucosaminidases (GlcNAcases) of various organisms including insects, fungi, mammals, and a plant but no inhibition against beta-glucosidase of almond, alpha-glucosidase of yeast, or chitinase of Bacillus sp. The GlcNAcase inhibitory activity of pochonicine (1) was comparable to nagstatin, a potent GlcNAcase inhibitor of natural origin.


Assuntos
Acetilglucosaminidase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Fungos/química , Alcaloides de Pirrolizidina/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Alcaloides de Pirrolizidina/isolamento & purificação
19.
J Am Chem Soc ; 130(12): 4146-52, 2008 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-18307344

RESUMO

A novel beta-N-acetylglucosaminidase (GlcNAcase) inhibitor named TMG-chitotriomycin (1) was isolated from the culture filtrate of Streptomyces anulatus NBRC13369. The strain produced 1 only when colloidal chitin was used as the sole carbon source in the production medium. The structure of 1 was determined by spectral and constitutive sugar analyses of the corresponding alditol derivatives to be an equilibrated mixture of alpha-d-N,N,N-triMeGlcNH2-(1,4)-beta-d-GlcNAc-(1,4)-beta-d-GlcNAc-(1,4)-d-GlcNAc and its C-2 epimer of the reducing end residue. TMG-chitotriomycin (1) showed potent and selective inhibition of insect and fungal GlcNAcases with no inhibition of mammalian and plant GlcNAcases. In contrast, the known GlcNAcase inhibitor nagstatin potently inhibited all GlcNAcases. It should be emphasized that synthesized d-N,N,N-triMeGlcNH2, which is the component sugar of 1, showed no inhibition of the insect Spodoptera litura GlcNAcase. These results suggest that the (GlcNAc)3 unit positioned at the reducing end of 1 is essential for its enzyme inhibitory activity. The unique inhibitory spectrum of 1 will be useful to study chitinolytic systems and to develop selective fungicides or pesticides.


Assuntos
Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Penicillium/enzimologia , Spodoptera/enzimologia , Streptomyces/metabolismo , Álcoois Açúcares/farmacologia , beta-N-Acetil-Galactosaminidase/antagonistas & inibidores , Animais , Bacillus/classificação , Bacillus/enzimologia , Configuração de Carboidratos , Sequência de Carboidratos , Quitinases/antagonistas & inibidores , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Insetos , Dados de Sequência Molecular , Sensibilidade e Especificidade , Especificidade da Espécie , Streptomyces/classificação , Streptomyces griseus/enzimologia , Relação Estrutura-Atividade , Álcoois Açúcares/química
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