Ethosomes in hair dye products as carriers of the major compounds of black tea extracts.

Objectives: This study describes a novel carrier, the ethosome-based system, which is composed of non-ionic surfactants, ethanol, and water.

Methods: Brij(®) 52 (non-ionic surfactants), soya phosphatidylcholine (PC), cholesterol, and the major compounds (caffeine and gallic acid) of black tea extracts were dissolved in the ethanolic phase. The aqueous phase containing Paragon III was heated to 60 °C and mixed with the previous solution.

Dermal delivery by niosomes of black tea extract as a sunscreen agent.

Objectives: The primary objective of this study was to investigate the feasibility of using niosomes as a delivery vehicle for the dermal administration in vitro of black tea extract (BTE) as a sunscreen.

Methods: Multi-lamellar niosomes were obtained by means of a previously reported method of lipid hydration films. In vitro penetration experiments through nude mouse skin were carried out to evaluate the potential of niosomes as a dermal formulation.

Microbial transformation of isosteviol lactone and evaluation of the transformation products on androgen response element.

Two filamentous fungi, Cunninghamella bainieri ATCC 9244 and Aspergillus niger BCRC 32720, were used to investigate the biotransformation of isosteviol lactone (4alpha-carboxy-13alpha-hydroxy-13,16- seco-ent-19-norbeyeran-16-oic acid 13,16-lactone) ( 2), which was derived by reacting isosteviol ( ent-16-oxobeyeran-19-oic acid) ( 1) with m-chloroperbenzoic acid. Incubation of 2 with C. bainieri afforded metabolites 3- 6, which involved isomerization, hydroxylation, and ring cleavage reactions followed by oxidation and selective O-methylation.

Microbial transformation of isosteviol and bioactivities against the glucocorticoid/androgen response elements.

Preparative-scale fermentation of isosteviol ( ent-16-oxobeyeran-19-oic acid) (1) with Mucor recurvatus MR 36, Absidia pseudocylindrospora ATCC 24169, and Aspergillus niger BCRC 32720 afforded nine known metabolites ( 2, 3, 5-10, and 14) and nine new metabolites ( 4, 11-13, and 15-19). The reactions involved stereoselective introduction of OH groups at positions C-1, -6, -7, -9, -11, -12, -15, and -17 as well as further ketonization at the C-1 and C-7 positions. The structures of the metabolites were established on the basis of 1D and 2D NMR and IR supported by HRFABMS.

Transformation of steviol-16alpha,17-epoxide by Streptomyces griseus and Cunninghamella bainieri.

Eight new ent-beyerane metabolites, 5-8, 12, and 14-16, and four new ent-kaurane metabolites, 3, 10, 11, and 13, together with two known metabolites, 4 and 9, were isolated from the microbial transformations of steviol-16alpha,17-epoxide using Streptomyces griseus ATCC 10137 and Cunninghamella bainieri ATCC 9244. The structures of the metabolites were characterized by IR, HRFABMS, and 1D and 2D NMR data. In addition, a GRE (glucocorticoid response element)-mediated luciferase reporter assay was used to initially screen for the biological activity of the 11 metabolites and stevioside.