Association (micellization) and partitioning of aglycon triterpenoids

Rafat, Marjan; Fong, Kit Wah; Goldsipe, Arthur; Stephenson, Brian C.; Coradetti, Samuel T.; Sambandan, T. G.; Sinskey, Anthony J.; Rha, ChoKyun

doi:10.1016/j.jcis.2008.05.046

Cited by 22 publications

(31 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In our cytotoxic test the cell viability dropped sharply when the TX100 concentration reached close to the CMC. Because the viability test was based on the integrity of the cell membrane, the micelle clearly showed a greater detergent action on the lipid bilayer than the individual surfactant molecule and hence was more toxic (27). Thus most of the studies by SECM were performed in the concentration range below the CMC to have enough time to observe the permeabilizing action on the cellular membrane by TX100 molecules.…”

Section: Resultsmentioning

confidence: 99%

Triton X-100 concentration effects on membrane permeability of a single HeLa cell by scanning electrochemical microscopy (SECM)

Koley

Bard

2010

Proc. Natl. Acad. Sci. U.S.A.

350

249

View full text Add to dashboard Cite

Changes in HeLa cell morphology, membrane permeability, and viability caused by the presence of Triton X-100 (TX100), a nonionic surfactant, were studied by scanning electrochemical microscopy (SECM). No change in membrane permeability was found at concentrations of 0.15 mM or lower during an experimental period of 30 to 60 min. Permeability of the cell membrane to the otherwise impermeable, highly charged hydrophilic molecule ferrocyanide was seen starting at concentrations of TX100 of about 0.17 mM. This concentration level of TX100 did not affect cell viability. Based on a simulation model, the membrane permeability for ferrocyanide molecules passing though the live cell membrane was 6.5 ± 2.0 × 10 -6 m/s. Cells underwent irreversible permeabilization of the membrane and structural collapse when the TX100 concentration reached the critical micelle concentration (CMC), in the range of 0.19 to 0.20 mM. The impermeability of ferrocyanide molecules in the absence of surfactant was also used to determine the height and diameter of a single living cell with the aid of the approach curve and probe scan methods in SECM.

show abstract

Section: Resultsmentioning

confidence: 99%

Triton X-100 concentration effects on membrane permeability of a single HeLa cell by scanning electrochemical microscopy (SECM)

Koley

Bard

2010

Proc. Natl. Acad. Sci. U.S.A.

350

249

View full text Add to dashboard Cite

show abstract

“…Such limited impact of AA and UA on the tested UPECs may probably be caused by the absence of the cholesterol in bacterial cells. Moreover, pentacyclic triterpenes can form micellar phases that could affect their incorporation into cell membrane and the ability to change the cell surface hydrophobicity (Rafat et al 2008). …”

Section: Discussionmentioning

confidence: 99%

Effect of asiatic and ursolic acids on morphology, hydrophobicity, and adhesion of UPECs to uroepithelial cells

2012

View full text Add to dashboard Cite

Adhesion of bacteria to epithelial tissue is an essential step in the progression of the urinary tract infections. Reduction of virulence factors responsible for microbial attachment may help to decrease or inhibit colonization of the host organism by pathogens. In the age of increasing bacterial antibiotic resistance, more and more attention is being paid to the use of plants and/or their bioactive components in the prevention and treatment of human infections. Asiatic acid (AA) and ursolic acid (UA), two plant secondary metabolites, were used as potential antibacterial agents. The current study aimed to determine the possible impact of AA and UA on morphology, hydrophobicity, and adhesion of clinical uropathogenic Escherichia coli strains (UPEC) to the uroepithelial cells. Our work describes for the first time the effects exerted by AA and UA on virulence factors of UPECs. The impact of both acids on the cell surface hydrophobicity of the investigated strains was very weak. The results clearly show the influence of AA and UA on the presence of P fimbriae and curli fibers, morphology of the UPECs cells and their adhesion to epithelium; however, some differences between activities of AA and UA were found.

show abstract

“…Although AA was solubilized in EtOH prior to the mixing of AA with MPH, EtOH-induced aggregation of MPH was negligible (result not shown). AA is an amphiphilic surfactant, which has three hydroxyl groups and one carboxylic group in the hydrophilic region, and pentacyclic triterpene with methyl groups in the hydrophobic part (Rafat et al, 2008). Therefore, AA can increase turbidity due to the induction of peptide-peptide or peptide-AA associations.…”

Section: Resultsmentioning

confidence: 99%

“…Such low solubility of AA in aqueous phase and the tendency to form micelle may limit the efficacy of AA in cell penetration. Nevertheless, the CMC of AA can be increased to 52-54 μM in the presence of dimethyl sulfoxide (DMSO); thus lowered the inhibition concentration of AA in animal cell models as reported by Rafat et al (2008).…”

Section: Introductionmentioning

confidence: 98%

See 1 more Smart Citation

Potential use of antioxidative mungbean protein hydrolysate as an anticancer asiatic acid carrier

Wongekalak

Sakulsom

Jirasripongpun

et al. 2011

Food Research International

View full text Add to dashboard Cite

Association (micellization) and partitioning of aglycon triterpenoids

Cited by 22 publications

References 30 publications

Triton X-100 concentration effects on membrane permeability of a single HeLa cell by scanning electrochemical microscopy (SECM)

Triton X-100 concentration effects on membrane permeability of a single HeLa cell by scanning electrochemical microscopy (SECM)

Effect of asiatic and ursolic acids on morphology, hydrophobicity, and adhesion of UPECs to uroepithelial cells

Potential use of antioxidative mungbean protein hydrolysate as an anticancer asiatic acid carrier

Contact Info

Product

Resources

About