Pharmaceutical industry ethanols

Plant carotenoids are still extracted at laboratory and industrial scales with solvent mixtnres of ethanol and ethyl acetate, bnt solvent extraction always bears the risk of toxic residnes in the extracts and this limits their use in large production applications in the food and pharmaceutical industries. 

Caco-2 model is easily affected by commonly used organic solvents or co-solvents [e.g., methanol, ethanol, polyethylene glycol (PEG), dimethyl sulfoxide (DMSO)] at relatively low concentrations (<1% v/v). Therefore, NCEs with poor aqueous solubility may not be adequately evaluated by this model. It has become a common practice in the pharmaceutical industry to test solubility of compounds before performing any other in vitro screens and eliminate NCEs with poor aqueous solubility, thus preventing false negatives due to this issue. 

According to Coimbra et solvents play a central role in the majority of chemical and pharmaceutical industrial processes. The most used method to obtain artemisinin (1) from A. annua is through the use of organic solvents such as toluene, hexane, cyclohexane, ethanol, chloroform and petroleum ether. Rodrigues et al described a low-cost and industrial scaled procedure that enables artemisinin (1) enhanced yields by using inexpensive and easy steps. Serial extraction techniques allowed a reduction of 65% in solvent consumption. Moreover, the use of ethanol for compound extraction is safer when compared to other solvents. Flash column pre-purification employing silicon dioxide (Zeosil ) as stationary phase provided an enriched artemisinin (1) fraction that precipitated in hexane/ethyl acetate (85/15, v/v) solution. These results indicate the feasibility of producing artemisinin (1) at final cost lowered by almost threefold when compared to classical procedures. 

Gravity sedimentation techniques are used commonly in effluent treatment processes for separation of activated sludge from aqueous solutions, in fuel ethanol production for recovery of yeast cells from aqueous ethanol solutions for recycle to the fermenter, and in the pharmaceutical industry for separation of solvent and aqueous phases in product recovery and isolation of impurities. 

The importance of selecting gravimetry instead of volumetry to measure liquid amounts in the pharmaceutical industry of liquid dosage forms is well illustrated by the volume contraction of water-ethanol and volume expansion of ethyl acetate-carbon disulfide liquid mixtures as well as a CS2-ethyl acetate system. The National Formulary (NF) diluted alcohol is a typical example of the volume nonadditivity of liquid mixtures [29], This solution is prepared by mixing equal volumes of alcohol [U.S. Pharmacopeia (USP)] USP and purified water (USP). The final volume of this solution is about 3% less than the sum of the individual volumes because of the contraction due to the mixing phenomenon [1], In addition, molecular interactions of surfactants in mixed monolayers at the air-aqueous solution interface and in mixed micelles in aqueous media also cause some contraction of volume upon mixing [30],... 

Processes for production of ethanol and acetone-butanol-ethanol mixture from fermentation products in membrane contactor devices were presented in Refs. [88,89]. Recovery of butanol from fermentation was reported in Ref. [90]. Use of composite membrane in a membrane reactor to separate and recover valuable biotechnology products was discussed in Refs. [91,92]. A case study on using membrane contactor modules to extract small molecular weight compounds of interest to pharmaceutical industry was shown in Ref. [93]. Extraction of protein and separation of racemic protein mixtures were discussed in Refs. [94,95]. Extractions of ethanol and lactic acid by membrane solvent extraction are reported in Refs. [96,97]. A membrane-based solvent extraction and stripping process was discussed in Ref. [98] for recovery of Phenylalanine. Extraction of aroma compounds from aqueous feed solutions into sunflower oil was investigated in Ref. [99]. 

Solvated crystals are also common in the chemical and pharmaceutical industries. Figure 2-18 shows the room temperamre solubility curve of ibuprofen-lysinate as a function of water content in ethanol. As shown in the figure, the crossover point between anhydrous solid and monohydrate is < 5% water. At room temperamre, ibuprofen-lysinate remains anhydrous when the water content is below 5% and transforms into monohydrate when the water content is above 5%. In this example, solvate and anhydrous materials also have different crystal habits, as shown in Fig. 2-19. 

MBR are finding fertile ground for application in biochemical synthesis [4.1, 4.2] for the production of a broad spectrum of products. These range from food, liquid fuels (e.g., ethanol), and plant metabolites, to fine chemicals, including medical products, flavoring agents, food colors, fragrances, etc. Biochemical synthetic processes are important in the pharmaceutical industry, because they allow the production of complex molecules, like hormones, which cannot be produced safely and efficiently with the more conventional techniques [4.3]. 

The pharmaceutical industry would prefer to make the gamma globulin/al-bumin separation with a UF membrane rather than Cohn fractionation (sequential precipitation with ethanol). But to do so, they would have to dilute the mixture way down to accomplish the separation. The processing of the large diluted volumes followed by concentration of the two fractions would make the membrane process more cumbersome and expensive than Cohn fractionation. 

The goal of this work was to establish a method that allowed the selection of batch size and agitation speed during scale-up, with the objective of reproducing the selectivity of the system as measured by the amount of ethanol formed. It is important to remember that in the pharmaceutical industry, scale-up often occurs using existing multipurpose equipment. In some cases, when economical factors allow, specialized pilot-plant equipment is designed. 

Ethanol is a colorless, clear liquid with a characteristic, pleasant odor. It is miscible in all proportions with water and readily miscible with many organic solvents (e.g., ethers, hydrocarbons, acids, esters, ketones, carbon disulfide, glycols, and other alcohols). Ethanol dissolves castor oil, cellulose nitrate with a low nitrate content, polar resins, and polymers. Ethanol in combination with aromatic compounds dissolves cellulose acetate. Mixtures of ethanol, aromatic hydrocarbons, and water are good solvents for some polyamides. Ethanol is extensively used in the chemical and pharmaceutical industries. It is employed as a raw material for many chemical syntheses (e.g., esterification, as an ethylating agent, and reaction medium). Ethanol is an excellent solvent, diluent, and extracting agent for fats, oils, paints, and... 

Medicinal use of wine was continuous from ancient times to the beginning of the twentieth century, but its supposed health effects kept changing. In ancient times, direct healing effects were attributed to it, whereas in the last century, the only use was as a solvent to extract or dissolve some ingredients during the preparation of certain pharmaceuticals. However, the composition of wine changes slightly each year, so the pharmaceutical industry discovered that a mixture of water and ethanol... 

In some cases, the purpose of the process is to produce more of the microbe, as when yeast cultures aie grown to supply needs for particular strains in specific applications. In other cases, the purpose of the process is to use the biochemical processes of the particular microbe to convert one material into other materials, as when biomass is fermented for the production of industrial ethanol, butanol (butyl alcohol), and other compounds. Highly specific and bioengineered microbial cultures are often used to produce proteins and other biochemicals for pharmaceutical and medical research. 

Small neutral organic compounds, such as urea or ethanol, also exhibit hydrotropic properties and are used in formulations, in the pharmaceutical industry in particular. 

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