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1.
Biology (Basel) ; 11(2)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35205120

RESUMO

In this study, a phosphate solubilizing microorganism was isolated from the soil of an agricultural field in Lithuania. Based on 16S rRNA gene sequence analysis, the strain was identified as Bacillus sp. and submitted to the NCBI database, Sector of Applied Bio-catalysis, University Institute of Biotechnology, Vilnius, Lithuania and allocated the accession number KY882273. The Bacillus sp. was assigned with the number MVY-004. The culture nutrient medium and growth conditions were optimized: molasses was used as a carbon source; yeast extract powder was used as an organic source; NH4H2PO4 was used as a nitrogen source; the culture growth temperature was 30 ± 0.5 °C; the initial value of pH was 7.0 ± 0.5; the partial pressure of oxygen (pO2) was 60 ± 2.0; the mixer revolutions per minute (RPM) were 25-850, and the incubation and the fermentation time was 48-50 h. Analysis using Liquid Chromatography Time-of-Flight Mass Spectrometry (LC-TOF/MS) results showed that Bacillus sp. MVY-004 produced organic acids such as citric, succinic, 2-ketogluconic, gluconic, malic, lactic, and oxalic acids. Furthermore, the experiment showed that Bacillus sp. MVY-004 can also produce the following phytohormones: indole-3-acetic (IAA), jasmonic (JA), and gibberellic (GA3) acids. In the climate chamber, the experiment was performed using mineral fertilizer (NPS-12:40:10 80 Kg ha-1) and mineral fertilizers in combination with Bacillus sp. MVY-004 cells (NPS-12:40:10 80 Kg ha-1 + Bacillus sp. MVY-004) in loamy soil. Analysis was performed in three climate conditions: normal (T = 20 °C; relative humidity 60%); hot and dry (T = 30 °C; relative humidity 30%); hot and humid (T = 30 °C; relative humidity 80%).

2.
Electron J Biotechnol ; 49: 34-41, Jan. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1291638

RESUMO

BACKGROUND: This work studied how the exposure to an unusual substrate forced a change in microbial populations during anaerobic fermentation of crude glycerol, a by-product of biodiesel production, with freshwater sediment used as an inoculum. RESULTS: The microbial associations almost completely (99.9%) utilized the glycerol contained in crude glycerol 6 g L 1 within four days, releasing gases, organic acids (acetic, butyric) and alcohols (ethanol, n-butanol) under anaerobic conditions. In comparison with control medium without glycerol, adding crude glycerol to the medium increased the amount of ethanol and n-butanol production and it was not significantly affected by incubation temperature (28 C or 37 C), nor incubation time (4 or 8 d), but it resulted in reduced amount of butyric acid. Higher volume of gas was produced at 37 C despite the fact that the overall bacterial count was smaller than the one measured at 20 C. Main microbial phyla of the inoculum were Actinobacteria, Proteobacteria and Firmicutes. During fermentation, significant changes were observed and Firmicutes, especially Clostridium spp., began to dominate, and the number of Actinobacteria and Gammaproteobacteria decreased accordingly. Concentration of Archaea decreased, especially in medium with crude glycerol. These changes were confirmed both by culturing and culture-independent (concentration of 16S rDNA) methods. CONCLUSIONS: Crude glycerol led to the adaptation of freshwater sediment microbial populations to this substrate. Changes of microbial community were a result of a community adaptation to a new source of carbon.


Assuntos
Bactérias/isolamento & purificação , Sedimentos Geológicos/microbiologia , Água Doce/microbiologia , Glicerol/metabolismo , Bactérias/metabolismo , Adaptação Biológica , Biocombustíveis , Fermentação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Anaerobiose
3.
J Pharm Sci ; 105(4): 1489-95, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27019962

RESUMO

A series of dasatinib crystalline forms were obtained, and a hierarchical cluster analysis of their powder X-ray diffraction patterns was performed. The resulting dendrogram implies 3 structural groups. The crystal structures of several solvates representing 2 of these groups were determined. The crystal structure analysis confirms the isostructurality of solvates within structural group I and suggests a correlation between solvent molecule size and trends in crystal structures within this group. In addition, the formation relationships in 2-solvent media between different dasatinib solvate groups were determined. The formation preference of solvates was found to follow the ranking group I > group III > group II.


Assuntos
Antineoplásicos/química , Dasatinibe/química , Análise por Conglomerados , Cristalização , Modelos Moleculares , Difração de Pó , Difração de Raios X
4.
Mol Pharm ; 12(8): 2981-92, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26086552

RESUMO

Solid-state cocrystallization is of contemporary interest because it offers an easy and efficient way to produce cocrystals, which are recognized as prospective pharmaceutical materials. Research explaining solid-state cocrystallization mechanisms is important but still too scarce to give a broad understanding of factors governing and limiting these reactions. Here we report an investigation of the mechanism and kinetics of isoniazid cocrystallization with benzoic acid. This reaction is spontaneous; however, its rate is greatly influenced by environmental conditions (humidity and temperature) and pretreatment (milling) of the sample. The acceleration of cocrystallization in the presence of moisture is demonstrated by kinetic studies at elevated humidity. The rate dependence on humidity stems from moisture facilitated rearrangements on the surface of isoniazid crystallites, which lead to cocrystallization in the presence of benzoic acid vapor. Furthermore, premilling the mixture of the cocrystal ingredients eliminated the induction time of the reaction and considerably increased its rate.


Assuntos
Ácido Benzoico/química , Química Farmacêutica , Cristalização/métodos , Isoniazida/química , Estabilidade de Medicamentos , Cinética , Solubilidade , Termodinâmica , Difração de Raios X
5.
Acta Crystallogr C Struct Chem ; 70(Pt 4): 392-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24705055

RESUMO

A new polymorph of the cinnamic acid-isoniazid cocrystal has been prepared by slow evaporation, namely cinnamic acid-pyridine-4-carbohydrazide (1/1), C9H8O2·C6H7N3O. The crystal structure is characterized by a hydrogen-bonded tetrameric arrangement of two molecules of isoniazid and two of cinnamic acid. Possible modification of the hydrogen bonding was investigated by changing the hydrazide group of isoniazid via an in situ reaction with acetone and cocrystallization with cinnamic acid. In the structure of cinnamic acid-N'-(propan-2-ylidene)isonicotinohydrazide (1/1), C9H8O2·C9H11N3O, carboxylic acid-pyridine O-H···N and hydrazide-hydrazide N-H···O hydrogen bonds are formed.


Assuntos
Acetona/química , Cinamatos/química , Isoniazida/análogos & derivados , Isoniazida/química , Isoniazida/síntese química , Ligação de Hidrogênio
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 129: 326-32, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-24747856

RESUMO

An experimental and theoretical investigation of protonation effects on the UV/Vis absorption spectra of imatinib showed systematic changes of absorption depending on the pH, and a new absorption band appeared below pH 2. These changes in the UV/Vis absorption spectra were interpreted using quantum chemical calculations. The geometry of various imatinib cations in the gas phase and in ethanol solution was optimized with the DFT/B3LYP method. The resultant geometries were compared to the experimentally determined crystal structures of imatinib salts. The semi-empirical ZINDO-CI method was employed to calculate the absorption lines and electronic transitions. Our study suggests that the formation of the extra near-UV absorption band resulted from an increase of imatinib trication concentration in the solution, while the rapid increase of the first absorption maximum could be attributed to both the formation of imatinib trication and tetracation.


Assuntos
Antineoplásicos/química , Benzamidas/química , Piperazinas/química , Prótons , Pirimidinas/química , Cristalografia por Raios X , Mesilato de Imatinib , Modelos Moleculares , Teoria Quântica , Espectrofotometria Ultravioleta
7.
Int J Pharm ; 432(1-2): 50-6, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22569228

RESUMO

The anti-depressant pharmaceutical tianeptine has been investigated to determine the dynamics of polymorph formation under various pH conditions. By varying the pH two crystalline polymorphs were isolated. The molecular and crystal structures have been determined to identify the two polymorphs. One polymorph is an amino carboxylic acid and the other polymorph is a zwitterion. In the solid state the tianeptine moieties are bonded through hydrogen bonds. The zwitterion was found to be less stable and transformed to the acid form. During this investigation an amorphous form was identified.


Assuntos
Antidepressivos Tricíclicos/química , Tiazepinas/química , Cristalização , Concentração de Íons de Hidrogênio , Difração de Pó , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 7): o1597, 2010 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-21587834

RESUMO

The crystal structure of the title compound, 2C(19)H(17)N(2) (+)·C(4)H(2)O(4) (2-), consists of centrosymmetric trimers built up of two crystallographically independent N,N'-diphenyl-benzamid-in-ium cations and one fumarate dianion, which is located on a centre of inversion. The components of the trimers are linked by N-H⋯O hydrogen bonding. In the cation, the outer rings make dihedral angles of 53.66 (5) and 78.38 (5)° with the central ring. The two outer rings make a dihdral angle of 81.49 (5)°.

9.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 6): o1062, 2008 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-21202581

RESUMO

In the title compound, alternatively called xylazine hydro-chloride monohydrate, C(12)H(17)N(2)S(+)·Cl(-)·H(2)O, the six-membered thia-zine ring is in a half-chair conformation. In the crystal structure, six component centrosymmetric clusters are formed via inter-molecular O-H⋯Cl, N-H⋯O and N-H⋯Cl hydrogen bonds involving xylazine cations, chloride anions and water mol-ecules.

10.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): m1027, 2008 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-21203019

RESUMO

The anion of the title compound, also called sygethin dihydrate, 2K(+)·C(18)H(20)O(6)S(2) (2-)·2H(2)O, has crystallographic inversion symmetry. The K(+) cation is surrounded by eight O atoms in a distorted cubic coordination geometry, forming extended K-O-S networks. There are also O-H⋯O hydrogen bonds.

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