The present study is concerned with the effect of low pH on continuous citric acid fermentation by Aspergillus niger strain SK-17. Microbial cultivations were carried out in a stainless steel stirred bioreactor of 15 L total capacity. The bioconversion of glucose to citric acid at low pH was investigated on cellulose fabric. Sucrose solution (100 g/l) was made to flow through capillaries of a v...

Three types of methods have been proposed for the determination of citric acid in urine. Salant and Wise (1) used the unspecific mercuric sulfate reagent of Deniges (2) in a study of the toxicity of citrates. Thunberg (3) developed an enzymatic method employing a dehydrogenase said to be specific for citrate. The remaining methods depend on the so called pentabromoacetone method of Stahre (4), ...

pollution arising from plastic waste materials caused a great worry for researchers who are interested in protection of environment. this problem shifts their subject to bio-polymers for applications in packaging industries. however, their low water barrier properties are a critical problem. the effects of citric acid and methyl cellulose on water vapor and oxygen permeabilities and mechanical ...

This study was conducted to determine the effect of foliar salicylic acid (SA) and citric acid (CA) applications on growth, biochemical characteristics and essential oil content of thyme (Thymus vulgaris L.) grown under field conditions. Salicylic acid (0.5 and 1 mM) and citric acid (5 and 10 mM) were applied three times during the vegetation at 15 day intervals. Results revealed that foliar ap...

Eggplant dip is an internationally popular appetizer, prepared in some instances under uncertain hygienic conditions with inconsistent refrigeration. This study examined the effects of citric acid on the survival of pathogenic microorganisms (Salmonella Typhimurium, Escherichia coli O157:H7 and Staphylococcus aureus) and naturally present organisms (lactic acid bacteria, LAB, aerobic bacteria, ...

background: localized gingival recession can be treated successfully via coronally positioned fl ap (cpf) and additional use of root surface demineralization agents. the purpose of this study was to evaluate the effects of additional use of ethylene diamine tetraacetic acid (edta) and citric acid as a root conditioner in association with cpf to cover localized buccal gingival recessions. materi...

  Objective: This study aimed to assess the destructive effects of citric acid, lactic acid and acetic acid produced from the fermentation of foods on primary teeth enamel.   Methods: This in vitro, experimental study was conducted on 24 sound primary teeth. The teeth were polished with a fine abrasive paper under running water. Tooth pieces measuring 3 × 4 × 3mm were cut out of the teeth and s...

The possibility of using glycerol and glycerol-containing waste from biodiesel manufacture as a carbon and energy source for microbiological production of citric acid has been studied. Acid formation on the selective media had previously been tested in 66 yeast strains of different genera (Candida, Pichia, Saccharomyces, Torulopsis and Yarrowia). Under growth limitation by nitrogen, 41 strains ...

BACKGROUND The use of fossil carbon sources for fuels and petrochemicals has serious impacts on our environment and is unable to meet the demand in the future. A promising and sustainable alternative is to substitute fossil carbon sources with microbial cell factories converting lignocellulosic biomass into desirable value added products. However, such bioprocesses require tolerance to inhibito...