No abstract

Red clover flowers are a rich source of isoflavones in the forms of biochanin A, formononetin, genistein, and genistin. A simple process was developed to recover isoflavones from red clover flowers as a nutraceutical product. Isoflavones were 1st extracted in alkaline water and insoluble polyvinylpolypyrrolidone (PVP) was then added to the extract for adsorbing isoflavones. The adsorbed isoflavones were subsequently eluted with ethanol and dried. The main steps of this process were optimized for the product yield and quality. The final product was an isoflavone concentrate, containing more than 20 wt% isoflavones, which represented a recovery of greater than 50% of the total isoflavone amount in red clover flowers.

Based on a lab-scale aqueous process for making skimmed soymilk, a membrane intensive scheme was developed to recover isoflavones as a separate product from the waste stream while soymilk was prepared as the main product. It was shown that, despite the protein binding, most extracted isoflavones permeated through the selected ultrafiltration membranes. Therefore, instead of solvents or adsorbents, a combination of ultrafiltration and diafiltration was used to separate isoflavones from the proteins and other bean components, and isoflavones were then concentrated by reverse osmosis. A yield of approximately 50% of the total amount of isoflavones in soybeans was eventually obtained in the reverse osmosis retentate, which could be dried to make an isoflavone supplement. With minor modifications, the process was readily adaptable to isoflavone recovery from soy protein processing with defatted soy flour. Crown

Isoflavones in red clover flowers were extracted and recovered using a new process that mainly comprised of ethanol extraction, membrane processing, micelle formation and drying. To obtain maximum isoflavone extraction an ethanol concentration between 40% and 50% in water was found to be optimal. The extracted isoflavones were processed by ultrafiltration for preliminary purification, and then concentrated by reverse osmosis. As ethanol was removed by evaporation, micelles were formed in the reverse osmosis retentate, which was dried to yield an isoflavoneenriched product. This product contained about 9% isoflavone highlighting its potential use as a direct nutraceutical supplement. Crown Copyright © 2006 Published by Elsevier Ltd. All rights reserved. Keywords: Isoflavones; Red clover flower; Extraction; Membrane and processIndustrial relevance: Isoflavones present in agricultural biomass are utilized as source of functional food supplements. Extraction and refining of isoflavones involves several steps and the process is very energy intensive. This work reports an interesting approach for extraction and refining of isoflavones by developing a new process, which is energy efficient and gives a final product, which contains sufficiently high amounts of isoflavones for consumer applications.

The effect of amphotericin B in an emulsion formulation on the integrity of monolayers of kidney cells has been studied. Whereas a conventional solubilized amphotericin formulation (Fungizone, Squibb) caused a loss in monolayer integrity at concentrations above 1 microgram mL-1, the emulsion formulation had no measurable effect on confluence at amphotericin concentrations up to 100 micrograms mL-1. The emulsion retained a comparable antifungal activity to that of Fungizone against Saccharomyces cerevisiae in suspension culture. These results parallel the observed erythrocyte lysis data obtained previously using amphotericin B emulsions, and suggest that the emulsion formulation may have a lower toxicity and improved therapeutic potential over existing formulations.