TIM-1 is a powerful tool for supplying valuable information about the effects of various gastrointestinal conditions on biopharmaceutical behavior and efficacy of drug delivery systems in the development of oral formulations.
The use of genetically engineered microorganisms such as bacteria or yeasts as live vehicles to carry out bioconversion directly in the digestive environment is an important challenge for the development of innovative biodrugs. A system that mimics the human gastrointestinal tract was combined with a computer simulation to evaluate the survival rate and cinnamate 4-hydroxylase activity of a recombinant model of Saccharomyces cerevisiae expressing the plant P450 73A1. The yeasts showed a high level of resistance to gastric and small intestinal secretions (survival rate after 4 h of digestion, 95.6% ؎ 10.1% [n ؍ 4]) but were more sensitive to the colonic conditions (survival rate after 4 h of incubation, 35.9% ؎ 2.7% [n ؍ 3]). For the first time, the ability of recombinant S. cerevisiae to carry out a bioconversion reaction has been demonstrated throughout the gastrointestinal tract. In the gastric-small intestinal system, 41.0% ؎ 5.8% (n ؍ 3) of the ingested transcinnamic acid was converted into p-coumaric acid after 4 h of digestion, as well as 8.9% ؎ 1.6% (n ؍ 3) in the stomach, 13.8% ؎ 3.3% (n ؍ 3) in the duodenum, 11.8% ؎ 3.4% (n ؍ 3) in the jejunum, and 6.5% ؎ 1.0% (n ؍ 3) in the ileum. In the large intestinal system, cinnamate 4-hydroxylase activity was detected but was too weak to be quantified. These results suggest that S. cerevisiae may afford a useful host for the development of biodrugs and may provide an innovative system for the prevention or treatment of diseases that escape classical drug action. In particular, yeasts may provide a suitable vector for biodetoxication in the digestive environment.
The aim of this study was to develop sustained release plant extracts as a potential alternative to antibiotic growth promoters for growing pigs. Pellets with a core based on microcrystalline cellulose and 3 active compounds (eugenol, carvacrol, and thymol) were prepared using rotary fluidized-bed technology. Two particle sizes were produced that had a mean size of approximately 250 and 500 mum. Results show the process was able to produce pellets with a spherical and homogenous form when 10% of the active compounds were incorporated into the core. When active compounds were increased to 20%, the pellet became stickier, and the yield decreased from 90 to 65%. Different amounts of coating in the form of an aqueous-based ethylcellulose (EC) dispersion (Surelease) were applied to the core to modify the release of active compounds. The efficacy of the coating was evaluated in vitro using a flow-through cell apparatus. The time to achieve 50 and 90% dissolution increased with the increase in particle size (P < 0.05) and the increase in EC-coating level from 10 to 20% (wt/wt; P < 0.05), indicating the ability of the process to slow release depending on particle size and the amount of polymer applied. Differences in the release of the active compounds were observed in the same formulation of pellets, except for the formulation with small 10%-EC-coated particles, in which the active compounds were rapidly dissolved (more than 85% in 15 min or less). For all other formulations, the dissolution time for eugenol was always faster than for thymol or carvacrol. The close monitoring of plant extract behavior in the gastrointestinal tract could become a key factor in the continued use of phyto-molecules as alternatives to antibiotic growth promoters and in optimizing the balance between cost and efficacy. Different microencapsulation technologies can be used, of which the rotary fluidized bed warrants consideration because of the quality of the products obtained.
The aim of this study was to develop sustained release microspheres of capsicum oleoresin as an alternative to in-feed additives. Two spray-cooling technologies, a fluidized air bed using a spray nozzle system and a vibrating nozzle system placed on top of a cooling tower, were used to microencapsulate 20% of capsicum oleoresin in a hydrogenated, rapeseed oil matrix. Microencapsulation was intended to reduce the irritating effect of capsicum oleoresin and to control its release kinetics during consumption by the animal. Particles produced by the fluidized air bed process (batch F1) ranged from 180 to 1,000 microm in size. The impact of particle size on release of capsaicin, the main active compound of capsicum oleoresin, was studied after sieving batch F1 to obtain 4 formulations: F1a (180 to 250 microm), F1b (250 to 500 microm), F1c (500 to 710 microm), and F1d (710 to 1,000 microm). The vibrating nozzle system can produce a monodispersive particle size distribution. In this study, particles of 500 to 710 microm were made (batch F2). The release kinetics of the formulations was estimated in a flow-through cell dissolution apparatus (CFC). The time to achieve a 90% dissolution value (T90%) of capsaicin for subbatches of F1 increased with the increase in particle size (P < 0.05), with the greatest value of 165.5 +/- 13.2 min for F1d. The kinetics of dissolution of F2 was slower than all F1 subbatches, with a T90% of 422.7 +/- 30.0 min. Nevertheless, because CFC systems are ill suited for experiments with solid feed and thus limit their predictive values, follow-up studies were performed on F1c and F2 using an in vitro dynamic model that simulated more closely the digestive environment. For both formulations a lower quantity of capsaicin dialyzed was recorded under fed condition vs. fasting condition with 46.9% +/- 1.0 vs. 74.7% +/- 2.7 for F1c and 32.4% +/- 1.4 vs. 44.2% +/- 2.6 for F2, respectively. This suggests a possible interaction between capsaicin and the feed matrix. Moreover, 40.4 +/- 3.9% of the total capsaicin intake in F2 form was dialyzed after 8 h of digestion when feed had been granulated vs. 32.4 +/- 1.4% when feed had not been granulated, which suggests that the feed granulation process could lead to a partial degradation of the microspheres and to a limitation of the sustained release effect. This study demonstrates the potential and the limitations of spray-cooling technology to encapsulate feed additives.
The aim of the study was to assess the ability of a dynamic in vitro model to determine the digestibility of OM, CP, and starch compared with a validated, static, in vitro method and in vivo ileal digestibility obtained from growing pigs fitted with a T-cannula. Five experimental diets with different carbohydrate types and level were assessed: a standard corn-based diet (ST) or the same diet with coarse ground corn (CC), 8% sugar beet pulp (BP), 10% wheat bran (WB), or 8% sugar beet pulp and 10% wheat bran (HF). In the in vivo experiment, diets CC and HF reduced (P = 0.015) ileal digestibility of OM compared with the ST diet. The inclusion of sugar beet pulp reduced (P = 0.049) ileal CP digestibility of the BP diet. This reduction was not statistically significant when sugar beet pulp was combined with the wheat bran in the HF diet. No differences were shown for in vivo starch digestibility among diets. With the static in vitro method, the OM disappearance was greater than that observed in the in vivo experiment. In this static method, the BP and HF diets reduced (P = 0.004 and < 0.001, respectively) the disappearance of the OM compared with the ST diet. The coarse grinding of corn did not alter OM digestibility but decreased (P = 0.005) the starch digestibility. The R(2) between the in vivo results and the static in vitro methods for OM and starch digestibility was 0.99 when the CC diet was not considered. The dynamic in vitro model yielded OM and CP digestibility coefficients comparable with those obtained in vivo for the ST and CC diets. However, the values were considerably affected by the incorporation of the fibrous ingredients. Diets BP, WB, and HF had decreased (P = 0.009, 0.058, and 0.004, respectively) OM digestibility compared with the ST diet. Protein digestibility was also decreased (P < 0.001, P = 0.019, and P = 0.003, respectively) with the BP, WB, and HF diets compared with the ST diet. However, digestibility was decreased to a greater extent in the BP diet than in the WB and HF diets, both of which contained wheat bran. The R(2) between the dynamic in vitro model and the in vivo results for CP digestibility was 0.99 when the CC diet was not considered. No differences were detected for starch digestibility among the diets with the dynamic in vitro model. This dynamic in vitro model yielded ileal digestibility results comparable with those obtained in vivo for CP and OM with a corn-soybean diet, or with a diet including coarse corn, but it underestimated digestibility when fibrous ingredients were included in the diet.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.