Nanochemistry and biotechnology

Changes in the quantitative composition of phenol carboxylic acids in the culture medium of the strain Bacillus subtilis IMV B-7023 at its cultivation with bentonite nanoparticles
Skorochod I.O., Roy A.O., Kurdish I.K.
Zabolotny Institute of Microbiology and Virology of the NAS of Ukraine, 
154, Acad. Zabolotny St., Kyiv, 03143, Ukraine.
E-mail: aphalina.77@gmail.com

Bentonite is a valuable kind of mineral raw material, which finds application in more than 200 directions. Thus, on the basis of the interaction of particles of this mineral with the bacteria Azotobacter vinelandii IMV B-7076 and Bacillus subtilis IMV B-7023 created a highly effective complex bacterial preparation Azogran for plant growing. These microorganisms synthesize a number of biologically active substances. In particular, B. subtilis IMV B-7023 is a producer of phenolic compounds (Ph-OH), which may have antioxidant properties. The influence of bentonite nanoparticles on the synthesis of these metabolites was not investigated. Therefore, an important task of the present is to study the interaction of nanomaterials with living organisms.
It was established that the growth activity of B. subtilis IMV B-7023 in the nutrient glucose-mineral medium with sodium glycerophosphate at adding of bentonite nanoparticles (0.05 – 0.5 g/L) was not altered.
Using HPLC it was found that clay mineral nanoparticles did not affect the metabolic profile of Ph-OH in the culture medium (CM) of bacilli, only on their quantitative composition. Thus, in the methanol extract of CM of the bacteria that were grown in a nutrient medium without the addition of nanomaterial were available: Gallic, 4-Hydroxyphenylacetic (4-HPA) and trans-Cinnamic acids. At cultivation of B. subtilis IMV B-7023 with 0.05 g/L of bentonite nanoparticles, in the methanol extract of CM of the bacteria, the concentration of gallic acid increased by 12.9%, trans-cinnamic acid – by 54.4%, and 4-HPA practically did not changed relative to the control variant. At adding in the nutrient medium of the investigated nanomaterial at concentration of 0.5 g/L the amount of gallic acid increased by 31.9% and 4-HPA by 54.8%, while the trans-cinnamic acid reduced by 35.1%, compared to the control.
Thus, the interaction of bentonite nanoparticles (0.05 – 0.5 g/L) with bacteria B. subtilis IMV B-7023 is accompanied by pronounced quantitative changes in the synthesis of phenol carboxylic acids by bacilli.