chemicallytechFine Chemical TechnologiesТонкие химические технологии2410-65932686-7575MIREA – Russian Technological University (RTU MIREA).10.32362/2410-6593-2024-19-5-418-428MYVCLWchemicallytech-2159Research ArticleBIOCHEMISTRY AND BIOTECHNOLOGYБИОХИМИЯ И БИОТЕХНОЛОГИЯSolubilization of n-hexadecane by micellar solutions of trehalolipid - surfactants of biological originСолюбилизация н-гексадекана мицеллярными растворами трегалолипида - ПАВ биологического происхожденияhttps://orcid.org/0000-0003-2736-080XНечаеваИ. А.NechaevaI. A.

Нечаева Ирина Александровна, к.б.н., доцент, доцент кафедры биотехнологии, Естественно-научный институт

300012, Тула, пр-т Ленина, д. 92

Scopus Author ID 22958438500

ResearcherID ABF-1379-2020

Irina A. Nechaeva, Cand. Sci. (Biol.), Associate Professor, Biotechnology Department, Institute of Natural Science

92, Lenina pr., Tula, 300012

Scopus Author ID 22958438500

ResearсherID ABF-1379-2020

nechaeva1902@gmail.comhttps://orcid.org/0000-0002-4894-4591ПарфеноваА. С.ParfenovaA. S.

Парфенова Анастасия Сергеевна, магистрант кафедры биотехнологии, Естественно-научный институт

300012, Тула, пр-т Ленина, д. 92

Anastasia S. Parfenova, Master Student, Biotechnology Department, Institute of Natural Science

92, Lenina pr., Tula, 300012

asya17.parfenova@mail.ruhttps://orcid.org/0000-0002-4894-4591ФилипповаА. С.FilippovaA. S.

Филиппова Анастасия Сергеевна, младший научный сотрудник, лаборатория экологической и медицинской биотехнологии БиоХимТехЦентра; магистрант кафедры биотехнологии, Естественнонаучный институт

300012, Тула, пр-т Ленина, д. 92

Anastasia S. Filippova, Junior Researcher, Laboratory of Environmental and Medical Biotechnology, BioChemTechCenter; Master Student, Biotechnology Department, Institute of Natural Science

92, Lenina pr., Tula, 300012

stasya.filippova.01@gmail.comhttps://orcid.org/0000-0003-4800-7706ФилоновА. Е.FilonovA. E.

Филонов Андрей Евгеньевич, д.б.н., профессор кафедры биотехнологии, Естественно-научный институт; ведущий научный сотрудник лаборатории биологии плазмид

300012, Тула, пр-т Ленина, д. 92

142290,  Пущино, пр-т Науки, д. 5

Scopus Author ID 35608598500

ResearсherID E-8335-2014

Andrey E. Filonov, Dr. Sci. (Biol.), Professor, Biotechnology Department, Institute of Natural Science; Leading Researcher, Laboratory of Plasmid Biology

92, Lenina pr., Tula, 300012

5, Nauki pr.,  Pushchino, Moscow oblast, 142290

Scopus Author ID 35608598500

ResearсherID E-8335-2014

filonov.andrey@rambler.ruТульский государственный университетРоссияTula State UniversityRussian FederationТульский государственный университет; Институт биохимии и физиологии микроорганизмов им. Г.К. Скрябина, Российская академия наук, Пущинский научный центр биологических исследований Российской академии наукРоссияTula State University; Pushchino Scientific Center for Biological Research, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of SciencesRussian Federation202403112024195418428Copyright © Nechaeva I.A., Parfenova A.S., Filippova A.S., Filonov A.E., 20242024Нечаева И.А., Парфенова А.С., Филиппова А.С., Филонов А.Е.Nechaeva I.A., Parfenova A.S., Filippova A.S., Filonov A.E.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.finechem-mirea.ru/jour/article/view/2159

Objectives. To isolate biosurfactants of glycolipid nature produced by oil hydrocarbon degrading bacteria and to establish their ability to solubilize hydrophobic compounds in the case of n-hexadecane.Methods. Trehalolipids were isolated from bacteria Rhodococcus erythropolis X5 (VKM Ac-2532 D) and Rhodococcus erythropolis S67 (VKM Ac-2533 D) included in the MikroBak biopreparation for the bioremediation of oil-contaminated territories. The genome of R. erythropolis X5 is deposited in the National Center for Biotechnology Information database under GenBank accession numbers CP044283 and CP044284, BioSample – SAMN12818508, BioProject – PRJNA573614, and SRA – PRJNA573614. The content of trehalolipid biosurfactants was estimated by the amount of trehalose in aqueous solutions of biosurfactants using the phenolsulfur method. The surface tension of the obtained aqueous solutions of biosurfactants was determined by the du Noüy ring method using a Kruss K6 tensiometer (Kruss, Germany). The critical concentration of micelle formation was determined by the inflection point on the curves of surface tension dependence on the concentration of the biosurfactant solution. In order to establish the solubilizing ability of biosurfactants, the residual concentration of n-hexadecane in an aqueous sample of different concentrations was determined using a gas chromatographic method of analysis.Results. At a constant surface tension of 24.2 mN/m and 25.0 mN/m for R. erythropolis X5 and R. erythropolis S67, respectively, the critical micelle concentration for both strains was 33 mg/L (3.8 ∙ 10−5 mol/L). The solubilizing effect of Rhodococcus trehalolipid micellar solutions against hydrophobic n-hexadecane was demonstrated by gas chromatographic analysis. The solubilization process was characterized using molar solubilization capacity (Sm), molar solubilization ratio (MSR), micelle–water partition coefficient (Km), and solubilization energy 0 (ΔGS ). It was shown that the solubilization process of n-hexadecane proceeds spontaneously 0 (ΔGS = −35.5 kJ/mol) and more efficiently (Sm = 4.3 mol/mol, MSR = 4.7 mol/mol) than in comparison with other biosurfactants of glycolipid nature.Conclusions. Based on the value of the molar solubilization coefficient, it can be concluded that trehalolipids of the R. erythropolis X5 strain solubilize n-hexadecane in aqueous solutions to a greater extent than compared to other biosurfactants of a glycolipid nature, but are inferior to synthetic surfactants.

Цели. Выделить биосурфактанты гликолипидной природы, продуцируемые бактериями-деструкторами углеводородов нефти, и установить их способность к солюбилизации гидрофобных соединений на примере н-гексадекана.Методы. Трегалолипиды выделяли из бактерий Rhodococcus erythropolis X5 (ВКМ Ac-2532 Д) и Rhodococcus erythropolis S67 (ВКМ Ac-2533 Д), входящих в биопрепарат «МикроБак» для биоремедиации нефтезагрязненных территорий. Геном R. erythropolis X5 депонирован в базе данных National Center for Biotechnology Information под номерами доступа GenBankCP044283 и CP044284, BioSample – SAMN12818508, BioProject – PRJNA573614 и SRA – PRJNA573614. Содержание трегалолипидных биосурфактантов оценивали по количеству трегалозы в водных растворах биосурфактантов с помощью фенольно-серного метода. Поверхностное натяжение полученных водных растворов биосурфактантов определяли методом отрыва кольца де Нуи с использованием тензиометра Kruss K6 (Kruss, Германия). Критическую концентрацию мицеллообразования определяли по точке перегиба на кривых зависимостях поверхностного натяжения от концентрации раствора биосурфактанта. Для установления солюбилизирующей способности биосурфактантов определяли остаточную концентрацию н-гексадекана в водной пробе различной концентрации с помощью газохроматографического метода анализа.Результаты. При постоянном поверхностном натяжении 24.2 мН/м и 25.0 мН/м для R. erythropolis X5 и R. erythropolis S67 соответственно значение критической концентрации мицеллообразования для обоих штаммов составило 33 мг/л (3.8 ∙ 10−5 моль/л). С помощью газохроматографического метода анализа показано солюбилизирующее действие мицеллярных растворов трегалолипидов родококков в отношении гидрофобного н-гексадекана. Процесс солюбилизации охарактеризовали с помощью молярной солюбилизирующей способности (molar solubilization capacity, Sm), молярного коэффициента солюбилизации (molar solubilization ratio, MSR), коэффициента распределения мицелла–вода (micelle–water partition coefficient, Кm) и энергии солюбилизации 0 (ΔGS ). Показано, что процесс солюбилизации н-гексадекана протекает самопроизвольно 0 (ΔGS = −35.5 кДж/моль) и более эффективно (Sm = 4.3 моль/моль, MSR = 4.7 моль/моль) по сравнению с другими биосурфактантами гликолипидной природы.Выводы. На основании величины молярного коэффициента солюбилизации можно сделать вывод, что трегалолипиды штамма R. erythropolis X5 в большей степени солюбилизируют н-гексадекан в водных растворах по сравнению с другими биосурфактантами гликолипидной природы, однако уступают синтетическим поверхностно-активным соединениям.

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The authors declare that there are no conflicts of interest present.