Structure–Activity Relationship Assessment of Sophorolipid Ester Derivatives against Model Bacteria Strains
Sophorolipids (SLs) are glycolipids that consist of a hydrophilic sophorose head group covalently linked to a hydrophobic fatty acid tail. They are produced by fermentation of non-pathogenic yeasts such as <i>Candida Bombicola</i>. The fermentation products predominantly consist of the d...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-05-01
|
| Series: | Molecules |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1420-3049/26/10/3021 |
| _version_ | 1797533551779905536 |
|---|---|
| author | Filbert Totsingan Fei Liu Richard A. Gross |
| author_facet | Filbert Totsingan Fei Liu Richard A. Gross |
| author_sort | Filbert Totsingan |
| collection | DOAJ |
| description | Sophorolipids (SLs) are glycolipids that consist of a hydrophilic sophorose head group covalently linked to a hydrophobic fatty acid tail. They are produced by fermentation of non-pathogenic yeasts such as <i>Candida Bombicola</i>. The fermentation products predominantly consist of the diacetylated lactonic form that coexists with the open-chain acidic form. A systematic series of modified SLs were prepared by ring opening of natural lactonic SL with <i>n</i>-alkanols of varying chain length under alkaline conditions and lipase-selective acetylation of sophorose primary hydroxyl groups. The antimicrobial activity of modified SLs against Gram-positive human pathogens was a function of the <i>n</i>-alkanol length, as well as the degree of sophorose acetylation at the primary hydroxyl sites. Modified SLs were identified with promising antimicrobial activities against Gram-positive human pathogens with moderate selectivity (therapeutic index, TI = EC<sub>50</sub>/MIC<i><sub>B. cereus</sub></i> = 6–33). SL-butyl ester exhibited the best antimicrobial activity (MIC = 12 μM) and selectivity (TI = 33) among all SLs tested. Kinetic studies revealed that SL-ester derivatives kill <i>B. cereus</i> in a time-dependent manner resulting in greater than a 3-log reduction in cell number within 1 h at 2×MIC. In contrast, lactonic SL required 3 h to achieve the same efficiency. |
| first_indexed | 2024-03-10T11:17:08Z |
| format | Article |
| id | doaj.art-7c278685afd043768ab37839e7b35f1c |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-10T11:17:08Z |
| publishDate | 2021-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-7c278685afd043768ab37839e7b35f1c2023-11-21T20:22:24ZengMDPI AGMolecules1420-30492021-05-012610302110.3390/molecules26103021Structure–Activity Relationship Assessment of Sophorolipid Ester Derivatives against Model Bacteria StrainsFilbert Totsingan0Fei Liu1Richard A. Gross2Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY 12180, USACenter for Biotechnology and Interdisciplinary Studies (CBIS), Rensselaer Polytechnic Institute, Troy, NY 12180, USACenter for Biotechnology and Interdisciplinary Studies (CBIS), Rensselaer Polytechnic Institute, Troy, NY 12180, USASophorolipids (SLs) are glycolipids that consist of a hydrophilic sophorose head group covalently linked to a hydrophobic fatty acid tail. They are produced by fermentation of non-pathogenic yeasts such as <i>Candida Bombicola</i>. The fermentation products predominantly consist of the diacetylated lactonic form that coexists with the open-chain acidic form. A systematic series of modified SLs were prepared by ring opening of natural lactonic SL with <i>n</i>-alkanols of varying chain length under alkaline conditions and lipase-selective acetylation of sophorose primary hydroxyl groups. The antimicrobial activity of modified SLs against Gram-positive human pathogens was a function of the <i>n</i>-alkanol length, as well as the degree of sophorose acetylation at the primary hydroxyl sites. Modified SLs were identified with promising antimicrobial activities against Gram-positive human pathogens with moderate selectivity (therapeutic index, TI = EC<sub>50</sub>/MIC<i><sub>B. cereus</sub></i> = 6–33). SL-butyl ester exhibited the best antimicrobial activity (MIC = 12 μM) and selectivity (TI = 33) among all SLs tested. Kinetic studies revealed that SL-ester derivatives kill <i>B. cereus</i> in a time-dependent manner resulting in greater than a 3-log reduction in cell number within 1 h at 2×MIC. In contrast, lactonic SL required 3 h to achieve the same efficiency.https://www.mdpi.com/1420-3049/26/10/3021sophorolipidsantimicrobial activitystructure–activity relationshipselectivitybacterial resistance |
| spellingShingle | Filbert Totsingan Fei Liu Richard A. Gross Structure–Activity Relationship Assessment of Sophorolipid Ester Derivatives against Model Bacteria Strains Molecules sophorolipids antimicrobial activity structure–activity relationship selectivity bacterial resistance |
| title | Structure–Activity Relationship Assessment of Sophorolipid Ester Derivatives against Model Bacteria Strains |
| title_full | Structure–Activity Relationship Assessment of Sophorolipid Ester Derivatives against Model Bacteria Strains |
| title_fullStr | Structure–Activity Relationship Assessment of Sophorolipid Ester Derivatives against Model Bacteria Strains |
| title_full_unstemmed | Structure–Activity Relationship Assessment of Sophorolipid Ester Derivatives against Model Bacteria Strains |
| title_short | Structure–Activity Relationship Assessment of Sophorolipid Ester Derivatives against Model Bacteria Strains |
| title_sort | structure activity relationship assessment of sophorolipid ester derivatives against model bacteria strains |
| topic | sophorolipids antimicrobial activity structure–activity relationship selectivity bacterial resistance |
| url | https://www.mdpi.com/1420-3049/26/10/3021 |
| work_keys_str_mv | AT filberttotsingan structureactivityrelationshipassessmentofsophorolipidesterderivativesagainstmodelbacteriastrains AT feiliu structureactivityrelationshipassessmentofsophorolipidesterderivativesagainstmodelbacteriastrains AT richardagross structureactivityrelationshipassessmentofsophorolipidesterderivativesagainstmodelbacteriastrains |