Search results for "Biological Availability"
showing 10 items of 182 documents
Toward Biopredictive Dissolution for Enteric Coated Dosage Forms
2016
The aim of this work was to develop a phosphate buffer based dissolution method for enteric-coated formulations with improved biopredictivity for fasted conditions. Two commercially available enteric-coated aspirin products were used as model formulations (Aspirin Protect 300 mg, and Walgreens Aspirin 325 mg). The disintegration performance of these products in a physiological 8 mM pH 6.5 bicarbonate buffer (representing the conditions in the proximal small intestine) was used as a standard to optimize the employed phosphate buffer molarity. To account for the fact that a pH and buffer molarity gradient exists along the small intestine, the introduction of such a gradient was proposed for p…
In vivo models and decision trees for formulation development in early drug development: A review of current practices and recommendations for biopha…
2018
The ability to predict new chemical entity performance using in vivo animal models has been under investigation for more than two decades. Pharmaceutical companies use their own strategies to make decisions on the most appropriate formulation starting early in development. In this paper the biopharmaceutical decision trees available in four EFPIA partners (Bayer, Boehringer Ingelheim, Bristol Meyers Squibb and Janssen) were discussed by 7 companies of which 4 had no decision tree currently defined. The strengths, weaknesses and opportunities for improvement are discussed for each decision tree. Both pharmacokineticists and preformulation scientists at the drug discovery & development interf…
Activity–Bioavailability balance in Oral Drug Development for a Selected Group of 6‐Fluoroquinolones
2002
Abstract A nomogram is proposed to select the best candidate in drug development studies with quinolones and is intended to substitute other possible models. The nomogram is referred to as an activity–bioavailability balance (ABB) because it includes the following two criteria: ABB= 1 / gm MIC ( drug candidate ) 1 /gm MIC ( ciprofloxacin ) · F calc \( drug candidate \) F calc ( ciproflaxacin ) . The in vitro activity of a group of 4′ N ‐alkyl‐ciprofloxacin derivatives was determined together with that of ciprofloxacin, initially against some reference strains and subsequently against 159 clinical isolates of eight selected species. The inverse of the geometric mean of the lowest concentrati…
Effects of elevated production of autochthonous dissolved organic matter on the freely dissolved concentration of cadmium
2018
Eutrophication enhances the production of autochthonous dissolved organic matter (DOM), which is a major driving factor behind the impairment of many aquatic ecosystems. In a mesocosm study, we investigated the effects of the abundance and composition of DOM on the potential bioavailability of cadmium (Cd) caused by eutrophication, using three-dimensional excitation-emission matrix fluorescence spectroscopy integrated with tangential flow ultrafiltration technology. The complexing capacity of DOM-Cd and the sorption distribution coefficient between DOM and the bulk solution was calculated based on a 1 : 1 complexation model. The fluorescent DOM was decomposed into three components (one prot…
An uptake and elimination kinetics approach to assess the bioavailability of chromium, copper, and arsenic to earthworms (Eisenia andrei) in contamin…
2019
The aim of this study was to determine the bioavailability of metals in field soils contaminated with chromated copper arsenate (CCA) mixtures. The uptake and elimination kinetics of chromium, copper, and arsenic were assessed in the earthworm Eisenia andrei exposed to soils from a gradient of CCA wood preservative contamination near Hartola, Finland. In soils contaminated with 1480–1590 mg Cr/kg dry soil, 642–791 mg Cu/kg dry soil, and 850–2810 mg Ag/kg dry soil, uptake and elimination kinetics patterns were similar for Cr and Cu. Both metals were rapidly taken up and rapidly excreted by Eisenia andrei with equilibrium reached within 1 day. The metalloid As, however, showed very slow uptak…
Bioaccessibility and decomposition of cylindrospermopsin in vegetables matrices after the application of an in vitro digestion model.
2018
Research on the human exposure to Cylindrospermopsin (CYN) via consumption of contaminated food is of great interest for risk assessment purposes. The aim of this work is to evaluate for the first time the CYN bioaccessibility in contaminated vegetables (uncooked lettuce and spinach, and boiled spinach) after an in vitro digestion model, including the salivar, gastric and duodenal phases and, colonic fermentation under lactic acid bacteria. The results obtained showed that the digestion processes are able to diminish CYN levels, mainly in the colonic phase, especially in combination with the boiling treatment, decreasing CYN levels in a significant way. Moreover, the potential decomposition…
ADME Prediction with KNIME: Development and Validation of a Publicly Available Workflow for the Prediction of Human Oral Bioavailability.
2020
In silico prediction of human oral bioavailability is a relevant tool for the selection of potential drug candidates and for the rejection of those molecules with less probability of success during the early stages of drug discovery and development. However, the high variability and complexity of oral bioavailability and the limited experimental data in the public domain have mainly restricted the development of reliable in silico models to predict this property from the chemical structure. In this study we present a KNIME automated workflow to predict human oral bioavailability of new drug and drug-like molecules based on five machine learning approaches combined into an ensemble model. Th…
Bioaccessibility of bioactive compounds after non-thermal processing of an exotic fruit juice blend sweetened with Stevia rebaudiana
2017
Abstract A comparative study of the bioaccessibility of bioactive compounds and antioxidant capacity in a fruit juice-Stevia rebaudiana mixture processed by pulsed electric fields (PEF), high voltage electrical discharges (HVED) and ultrasound (USN) technology at two equivalent energy inputs (32–256 kJ/kg) was made using an in vitro model. Ascorbic acid was not detected following intestinal digestion, while HVED, PEF and USN treatments increased total carotenoid bioaccessibility. HVED at an energy input of 32 kJ/kg improved bioaccessibility of phenolic compounds (34.2%), anthocyanins (31.0%) and antioxidant capacity (35.8%, 29.1%, 31.9%, for TEAC, ORAC and DPPH assay, respectively) compared…
Apple-products phytochemicals and processing: a review.
2009
Epidemiological studies have linked the consumption of apples with reduced risk of some cancers, cardiovascular disease, asthma, and diabetes. Extensive research exists on apples and the health benefits of their beverages and phytochemicals. The purpose of this paper is to review the most recent literature in this area focusing on phytochemicals, phytochemical bioavailability and antioxidant behavior.
Influence of different soluble dietary fibers on the bioaccessibility of the minor Fusarium mycotoxin beauvericin.
2011
Abstract Beauvericin (BEA) is a bioactive compound produced by the secondary metabolism of several Fusarium strains and is known to have various biological activities. This study investigated the bioaccessibility of the BEA tested in concentrations of 5 and 25 mg/L, in a model solution and in wheat crispy breads elaborated with different natural binding compounds as the soluble alimentary dietary fibers β-1,3 glucan, chitosan low molecular weight (L.M.W.), chitosan medium molecular weight (M.M.W.), fructooligosaccharides (FOS), galattomannan, inulin and pectin, added at concentrations of 1% and 5%. The bioaccessibility was determinated by employing a simulated gastrointestinal digestion tha…