One humped camel (Camelus dromedarius) breeds, indigenous to India, have been shown to have good genetic potential to produce milk. Camel milk not only is cost-effective in terms of feed conversion but also has additional advantage of longer lactation period and unique adaptation mechanisms for warm arid and semiarid regions. The key features of camel milk in comparison with other milk are low fat with high content of unsaturated and long-chain fatty acid. The proteins are rich in lactoferrin and lysozymes, but deficient in b-lactoglobulin. It has higher percentage of total salts, free calcium, protective proteins and vitamin C, and some of the microminerals, viz iron, copper and zinc. Physicochemical properties of camel milk are also unique and useful for food processing. The shelf life of raw camel milk is 8-9 h, which can be extended up to 18-20 h through activation of camel lactoperoxidase system. Heat stability of camel milk is shown to be highest at pH 6.8, and it ferments relatively slowly compared to the cattle milk. The camel milk is successfully processed for producing a variety of products, such as fermented milk ('lassi'), soft cheese, flavored milk and 'kulfee' (a kind of ice cream). Camel milk has been traditionally used in different regions of the world as natural adjuvant for managing a variety of human diseases.

Glycogen in Saccharomyces cerevisiae is present in two pools, one soluble and intracellular, the other present in the cell wall and rendered water-insoluble owing to its covalent linkage to cell wall b-glucan. The insoluble glycogen fraction was solubilized using b-1,3-glucanase. The ab-glucan complex obtained showed intense red staining with iodine and was isolated from free b-glucans by affinity chromatography using concanavalin A sepharose 4B. Further use of molecular sieving has confirmed that glycogen is linked to b-glucan as the non-retained fraction on Biogel P2 split into two peaks on treatment with amyloglucosidase. Partial acid hydrolysis and subsequent paper chromatography of the ab-glucan complex isolated revealed the presence of gentiobiose and other higher oligosaccharides, indicating that glycogen is linked to b-1,3-glucan through a b-1,6 branch. The insoluble glycogen can be extracted in a soluble form by acetic acid treatment and is known as acid-soluble glycogen. The presence of glycogen in the cell wall is confirmed by controlled enzymatic release of ab-glucan complex using lyticase from Arthobacter luteus without disruption of the plasma membrane, as can be visualized using electron microscopy.

The effect of different extraction procedures on the yields of water-soluble and water-insoluble glycogen fractions from a number ofSaccharomyces strains was studied by using a specific method for glycogen determination. The similarity of the yields obtained by the different procedures showed that neither form of glycogen is an artifact, and variations in the relative amounts of glycogen in the two fractions during cell growth and in different yeast strains suggest that they represent different pools of storage material with specific roles in cell development and differentiation. A proportion of the water-insoluble glycogen fraction, solubilized by mechanical agitation, was shown to be strongly associated with a

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