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Principles and Methods of Ocular Pharmacokinetic Evaluation
Published in David W. Hobson, Dermal and Ocular Toxicology, 2020
One of the primary determinants of the penetration of any chemical into ocular tissues and compartments is the partition coefficient of the compound under investigation. The partition coefficient is a measure of the relative solubility of a compound in a lipid vs. an aqueous phase. These values are often given as the ratio of solubility of a substance in an organic solvent (e.g., ether, isobutanol, octanol) or oil (e.g., olive oil) to that in water. High values (e.g., 10 to 10-2) indicate that a compound is very lipid soluble, while low values (e.g., 10-4 to 10-6) conversely indicate a high aqueous solubility, or lipophobicity. It is important to have some knowledge of this determinant, especially in relation to the route of access that the compound will have relative to the eye. For example, a compound that is lipid soluble will have less difficulty passing through the cornea if applied as a topical drop or if it has access to the ocular surface, than will a more water-soluble compound. This is due to the composition of the cornea, with its highly lipid-containing, cellular epithelium covering the anterior surface. An excellent illustration of this might be the transcorneal penetration of lipid- and water-soluble steroids. With the epithelium present, only the lipid-soluble drugs penetrated the entire cornea, while in the absence of epithelium, no marked differences occurred in the penetration of lipid- and water-soluble steroids.10
Quality Control of Ayurvedic Medicines
Published in D. Suresh Kumar, Ayurveda in the New Millennium, 2020
V. Remya, Maggie Jo Alex, Alex Thomas
Temperature has a general accelerating effect on fermentation. At higher temperatures (35°C) the carbon dioxide dissolved in the fermentation medium gets converted to compounds like fusel oils (isoamyl alcohol and phenyl ethanol) and higher alcohols like 1-propanol, 1-butanol, 2-butanol, isobutanol, isoamyl alcohol and 1-hexanol which cause liver disease (Lachenmeier et al. 2008). The maximum specific growth rate of yeast is known to be at 25°C (Torija et al. 2003; Şener et al. 2007). Therefore, it is desirable to keep fermentation temperatures of ariṣṭa and āsava around 25°C.
Detection And Identification of Drugs of Dependence
Published in S.J. Mulé, Henry Brill, Chemical and Biological Aspects of Drug Dependence, 2019
Fulton127 showed that a fluorescent product of morphine could be prepared by heating the drug in 0.5 cc of sulfuric acid, with subsequent dilution of the material in water and the addition of concentrated NH4OH. Naudeau and Sobolewski128 used essentially the same technique with a subsequent extraction into isobutanol. The compound was excited at 365 nm, with emission at 430 nm.
Semi-Purified Saponins of Holothuria poli Associated Antiproliferation in Tumor Cell Lines
Published in Nutrition and Cancer, 2022
Nazli Mert-Ozupek, Yasemin Basbinar, Tugba Uysal-Kilic, Omer Koz, Hulya Ellidokuz, Levent Cavas
The sea cucumber samples were extracted by using the method of Bondoc et al. (7). Briefly, the body walls of the frozen samples were homogenized and extracted three times with 70% ethanol-water (v/v). The filtered extracts were evaporated at 42 °C by using rotary evaporator. The dry material was extracted with 90% methanol and n-hexane (v/v) by using liquid–liquid extraction procedure. Then, the separated hydromethanolic phase was adjusted to 20% (v/v) and 40% (v/v) water and extracted with dichloromethane and chloroform, respectively. Then, the hydromethanolic phase was evaporated until dry at 42 °C by using rotary evaporator. The evaporated extract was diluted in water and partitioned against isobutanol (v/v). Finally, the isobutanolic phase was evaporated at 42 °C by using rotary evaporator and pH 7.4 Milli-Q water was added in order to undergo the antiproliferative activity. The TTG composition of the extracts were analyzed by using MALDI-TOF/MS. In order to determine the total TTG concentrations in each extract, vanillin-sulfuric acid colorimetric assays were carried out according to the method of Hiai, Oura, and Nakajima, 1976 (25). As standard, Quillaja bark saponin (Sigma- Aldrich, St. Louis, MO) was used.
Infant gut microbiota modulation by human milk disaccharides in humanized microbiome mice
Published in Gut Microbes, 2021
Antonio Rubio-Del-Campo, Roberto Gozalbo-Rovira, Eva M. Moya-Gonzálvez, Juan Alberola, Jesús Rodríguez-Díaz, María J. Yebra
SCFAs were extracted from large intestine content and analyzed by gas chromatography mass spectrometry (GC/MS) as described in the Agilent application note.84 Briefly, 30 mg of intestinal content were suspended in 1 ml 10% isobutanol and mechanically homogenized with glass beads The mixtures were centrifuged at 17,000 g for 5 min. Sample supernatants and standards were treated and subjected to the derivatization procedure as described in the Agilent application note, and 3-methylpentanoic acid was used as internal standard. Analysis of SCFAs was performed on an Agilent 7890B GC/5977 MSD (Agilent, Santa Clara, CA, USA) using a Agilent HP-5 ms column (30 m × 0.25 mm × 0.25 µm). The injector temperature was set at 260°C in split mode (10:1) and a volume of 1 µl was automatically set. The column temperature was initially 40°C for 5 min and then increased to 120°C at 10°C/min and then ramped to 310°C at 40°C/min and held for 2 min. The MS transfer line was maintained at 280°C and the ion source at 230°C.
Development and evaluation of a novel drug delivery: Soluplus®/TPGS mixed micelles loaded with piperine in vitro and in vivo
Published in Drug Development and Industrial Pharmacy, 2018
Yingying Ding, Changyuan Wang, Yutong Wang, Youwei Xu, Jing Zhao, Meng Gao, Yanfang Ding, Jinyong Peng, Lei Li
In vitro cytotoxicity of piperine-loaded Soluplus®/TPGS mixed micelles was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT, Solarbio) assay. A549 and HepG2 cells lines were seeded in 96-well culture plates at the density of per well. After 24 h of incubation, cells were handled with piperine-loaded Soluplus®/TPGS mixed micelles of different concentrations, empty micelles, physical mixture, and piperine solution dissolved in dimethyl sulfoxide (DMSO). The culture medium without any drug formulation was used as control. After incubation for 24 or 48 h, cell viability was determined by incubation with medium containing MTT (5 mg/ml) for 4 h at 37 °C. A 100-µl aliquot of SDS-isobutanol-HCl solution was added and left to incubate overnight. The absorbance of each well at 570 nm was measured using a microplate reader (Bio-Rad Laboratories, San Diego, CA). The results were analyzed based on at least three independent experiments.