Isolation and identification by 16S rRNA sequence analysis of plant growth-promoting azospirilla from the rhizosphere of wheat

ABSTRACT The main objective of the present study was to isolate phytohormone-producing, phosphate-solubilizing strains of Azospirillum from wheat to be used as inoculants for plant growth promotion. Five Azospirillum strains were isolated from the rhizosphere of field-grown wheat (Triticum aestivum L.), and it was confirmed by BOX-polymerase chain reaction (PCR) that the isolates were different and not re-isolates of the same strain. Sequence analysis of the PCR-amplified 16S rRNA gene indicated that four isolates showed maximum similarity to Azospirillum brasilense and one isolate showed maximum similarity to Azospirillum zeae. This is the first report indicating the presence of an A. zeae like isolate in the wheat rhizosphere in Pakistan. The bacterial isolates were characterized for their plant growth-promoting traits, phosphate solubilization, and indole-3-acetic acid (IAA) production. None of the isolates showed phosphate solubilization activity in the commonly used Pikovskaya medium. However, all strains (except AzoK4) exhibited ability to solubilize tricalcium phosphate (TCP) in modified Pikovskaya medium in which sucrose was replaced by Na-malate, as well as in TCP-supplemented Luria-Bertani (LB) medium. Organic acids, such as acetic, citric, lactic, malic, and succinic acids, were detected in culture supernatants of the tested Azospirillum strains. All strains exhibited ability to produce IAA in the growth medium, except Azospirillum sp. AzoK1. Among the strains tested, the maximum IAA production (30.49 ± 1.04 mg L-1) and phosphate solubilization (105.50 ± 4.93 mg L-1) were shown by a pure culture of Azospirillum sp. AzoK2. In pot experiments, single-strain inocula of Azospirillum sp. AzoK1 and AzoK2 improved wheat plant growth.

[Effect of magnetic field with 100 microT density on rat bone resorption]

Electromagnetic fields are present everywhere in our environment with various intensities, so, investigation about their effects on living organism is very important. The aim of this experiment study to investigate the effect of magnetic field on bone resorption, PTH and calcitonin concentration and their correlations. In this experimental research, 30 Sprague-Dawley male rats were divided into 3 groups. Test group animals, were exposed to magnetic field [100 micro T, 50 Hz], 4 hours per day for a period of 42 days. Experimental condition for control-1 group was the same as test group, except that, they were not exposed. Animals of control-2 group were killed at the first day of experiment [day 0]. Total left femoral bone calcium and phosphorus content and its fracture energy was measured at days 28 and 42 in control-1 and test group and on day 0 in control-2 group. However, serum calcium, phosphorus, PTH and calcitonin concentration were measured on day 0, the first day of exposure, and thereafter once per two weeks. Total bone calcium content in test group was significantly lower than control-1 and 2 groups, and bone fracture energy showed a slightly decrease. On the other hand, serum calcium and phosphorus concentration increased significantly on 28[th] and 42[nd] days compared to day 0. There was a decrement in serum PTH concentration and increment in serum calcitonin concentration during the exposure period. Our results suggested that magnetic field could have a direct effect on bone resorption, and observed changes in PTH and calcitonin were in good correlation with serum calcium and phosphorus concentrations [negative feed back] and these changes also prevent further increase in bone resorption

Citomegalovirosis cutánea en un paciente con SIDA / Cutaneous cytomegalovirus infection in an AIDS patient

Presentamos un paciente con SIDA, de sexo masculino y 43 años de edad, con una úlcera localizada en el cuerpo de pene de 6 meses de evolución. En el estudio histopatológico se observó la presencia de células con numerosas inclusiones intracitoplasmáticas irregulares y basofílicas y en las células endoteliales inclusiones intranucleares prominentes, redondeadas,rodeadas de un halo claro. Esto permitió llegar al diagnóstico de lesión ulcerosa crónica vinculable a infección por citomegalovirus. Se consideran además, en este artículo, otros métodos diagnósticos, así como la terapéutica de la entidad

Sintese de novos derivados do acido 3-fosfonopropionico / Synthesis of new derivatives of 3-phosphonopropionic acid

Foram sintetizadas tres series de derivados do acido 3-fosfonopropionico, compreendendo 22 substancias, das quais 16 ainda nao descritas na literatura. Todas as substancias foram caracterizadas por analise elementar, espectroscopia no infravermelho e espetrometria de ressonacia magnetica protonica. Os compostos obtidos foram encaminhados para ensaios experimentais na doenca de Chagas

Ensaio biologico de novos derivados do acido 3-fosfonopropionico contra o TRYPANOSOMA CRUZI / Biological assay of new derivatives of 3-phosphonopropionic acid against TRYPANOSOMA CRUZI

Diversos derivados do acido 3-fosfonopropionico foram submetidos a ensaios in vivo e in vitro, contra formas tripomastigotas da cepa Y de Trypanosoma Cruzi. Nos ensaios in vivo, realizados em camundongos previamente infectados,os derivados ensaiados se mostraram inativos, sendo que os acidos (R,S)-3-fenil-3-fosfonopropionico e (R,S)-3-fenil-3-(0,0-dietilfosfono)-propionico foram letais para alguns dos animais. Nos ensaios in vitro efetuados em cultura de tecido os compostos ensaiados foram inativos, com excecao do (R,S)-3-fenil-3-(0,0-dietilfosfono)-propionato de etila, que apresentou alguma atividade.

Reactions of phosphorous oxychloride-amide adducts XIII A novel synthesis of 1-N,N-Dime-thylamino-1-ethoxyethylene

Meerwein et aL[1] succeeded in the preparation of l-N,N-dimethylamino-1-ethoxyethylene [1]. Bredereck and co-workers [2] obtained the ethoxyenamine from the reaction of N,N-dimethylacetamide- dimethylsulphate adduct with sodium ethoxide followed by distillation over calcium metal. Electrophilic addition to the double bond in the ethoxyenamine [1] has been reported. With acid chlorides, the enamine afforded the corresponding beta- ketoamides [3]. We would like to report a direct and simple method for the synthesis of the ethoxyenamine. This compound has now been prepared by the treatment of dimethylacetamide-ethyl chloroformate adduct [4] with triethylamine, whereby CO[2] is evolved

reaction of alkyl phosphites with p-quinone-anils

The reaction of antbxaquinone anil [I] and p-naphthoquinone anil [III] with di-, and trialkyl phosphites under different condition, is studied. The uncatalyzed reaction with dialkyl phosphites affects tail-to-tail dimerization of anil I to give IV. Structural reasonings based on chemical and spectroscopic evidence, are presented

reaction of alkyl phosphites with asymmetric p-quinones khellinquinone and psoralenequinone

The reaction of khellinquinone 1 with trialkyl phosphites under varying experimental conditions, has been investigated. In methylene chloride, the reaction of quinone 1 with trimethyl phosphite and triethyl phosphite afforded, mainly, the respective monoalkyl ethers [15 and 16] of khellinquinol 12. The behaviour of psoralenequinone 2 towards attack by dimethyl phosphite and trimethyl phosphite, was also studied. Possible reaction-mechanisms have been considered and structural reasonings were based upon analytical, chemical and spectroscopic grounds