A novel niosome formulation for encapsulation of anthocyanins and modelling intestinal transport.

The bioavailability of drugs can be improved by regulating the structural properties, particularly lipoid systems, such as niosomes, can increase cellular uptake. Herein, we optimized double emulsion and niosomal formulations for encapsulating anthocyanin-rich black carrot extract. Nanoparticles obtained by selected formulation were characterized in terms of morphology, particle size, drug encapsulation efficiency, in vitro release and cytotoxicity. The optimum conditions for niosomal formulation were elicited as 30 mg of cholesterol, 150 mg of Tween 20 and feeding time of 1 min at a stirring rate of 900 rpm yielding the lowest average particle size of 130 nm. In vitro release data showed the majority of the encapsulated anthocyanins were released at the end of 10 h. A mathematical model was developed to estimate the absorption of anthocyanins released from niosomes and cytotoxicity was assessed against neuroblastoma. Overall, these findings suggest that niosomal vesicles might be suitable delivery systems for anthocyanins.

Monitoring of the effects of transfection with baculovirus on Sf9 cell line and expression of human dipeptidyl peptidase IV.

Human dipeptidylpeptidase IV (hDPPIV) is an enzyme that is in hydrolase class and has various roles in different parts of human body. Its deficiency may cause some disorders in the gastrointestinal, neurologic, endocrinological and immunological systems of humans. In the present study, hDPPIV enzyme was expressed on Spodoptera frugiperda (Sf9) cell lines as a host cell, and the expression of hDPPIV was obtained by a baculoviral expression system. The enzyme production, optimum multiplicity of infection, optimum transfection time, infected and uninfected cell size and cell behavior during transfection were also determined. For maximum hDPPIV (269 mU mL(-1)) enzyme, optimum multiplicity of infection (MOI) and time were 0.1 and 72 h, respectively. The size of infected cells increased significantly (P < 0.001) after 24 h post infection. The results indicated that Sf9 cell line was applicable to the large scale for hDPPIV expression by using optimized parameters (infection time and MOI) because of its high productivity (4.03 mU m L(-1) h(-1)).

Microbial transformation of cycloastragenol.

The microbial transformation of cycloastragenol by the fungi Cunninghamella blakesleeana NRRL 1369 and Glomerella fusarioides ATCC 9552, and the bacterium Mycobacterium sp. NRRL 3805 were investigated. Both fungi mainly provided hydroxylated metabolites together with products formed by cyclization, dehydrogenation and Baeyer-Villiger oxidation resulting in a ring cleavage. The bacteria yielded only a single oxidation product, namely, 3-oxo-cycloastragenol. Structures of the metabolites were elucidated by 1-D ((1)H,(13)C), 2-D NMR (COSY, HMBC, HMQC) and HRMS analyses.

Production and separation of dipeptidyl peptidase IV from Lactococcus lactis: scale up for industrial production.

Lactococcus lactis spp. lactis and Lactococcus lactis spp. cremoris are widely used in the manufacture of fermented milk. These strains were compared for production of Dipeptidyl Peptidase IV (DPP IV) enzyme in terms of enzyme activity, specific growth rates and productivity. Lactococcus lactis spp. lactis was produced in 3 L bioreactor and scaled up to 30 and 150 L stirred tank bioreactors, and the enzyme activities were found as 110, 110 and 122 mU mL(-1), respectively. After 8 h of production, separation steps were performed. While purification fold was 127 and yield was 2.69 %, the molecular weight of the enzyme was estimated as 68 kDa. Partially purified enzyme was enteric coated with capsules and a 95.5 % of DPP IV enzyme passed into the artificial intestine. Results show that production of DPP IV enzyme by Lactococcus lactis spp. lactis strain in submerged culture is comparable with the productions by commercial strains, mostly Aspergillus, in solid state fermentations based on productivity.

Biotransformation of cycloastragenol by Cunninghamella blakesleeana NRRL 1369 resulting in a novel framework.

The microbial transformation of cycloastragenol by the fungus Cunninghamella blakesleeana NRRL 1369 was investigated. Unlike the original compound, the metabolite was found to possess an interesting triterpenic skeleton derived via an exceptional transformation involving ring cleavage and methyl group migration. The structure of the new metabolite was elucidated by 1-D ((1)H, (13)C) and 2-D NMR (COSY, HMBC, HMQC, NOESY) techniques and MS analyses.

Modulated release of a volatile compound from starch matrixes via enzymatically controlled degradation.

The release of a model volatile (diacetyl) from a system based on a starch matrix, in which the volatile is dispersed, was studied. Kneading was used to obtain a homogeneous mixture (melt) composed of starch, glycerol alpha-amylase, and diacetyl. Samples were then ground to powders. When the starch powders were exposed to 30% relative humidity (RH) at 20 degreesC, no degradation of the starch matrix occurred. The samples only showed an initial burst release of diacetyl (around 10% of the loaded dose), whereas the remaining amount of diacetyl was not released, most likely due to the glassy character of the matrix and the low solubility of diacetyl in the matrix. However, when the samples were incubated at 90% RH, due to the uptake of moisture by the particles full release of the entrapped volatile occurred. The release of diacetyl from the matrix without enzyme followed first-order kinetics and, as expected, the release rate increased with decreasing particle size. Due to absorption of water, the enzyme became active and starch degradation occurred. The initial release of diacetyl from amylase-containing matrixes followed first-order kinetics as well. However, once the matrix was degraded to a certain extent, the particles collapsed, which was associated with concomitant rapid increase in release. The time at which the particle collapse occurred decreased with increasing enzyme concentration in the matrix. In conclusion, it is demonstrated that the release of a volatile from starch matrixes can be modulated both by the amount of coencapsulated matrix-degrading enzyme and by the humidity of the environment.