Lipolytic fermentations of stickwater by Geotrichum candidum and Candida lipolytica.

Stickwater, a by-product of the fish meal and oil industry, is an aqueous suspension of fish proteins, lipids, and other materials, and also contains soluble nonprotein nitrogen but not carbohydrate. It is usually partially evaporated by heat to a marketable form called "fish solubles," which is sold with an acid preservative as an animal feed supplement. However, fish solubles are only used to a limited extent in feeds, because the lipids of solubles (averages 11%) are relatively prone to oxidative rancidity development. An investigation was undertaken to digest and/or stabilize lipids in stickwater by lipolytic fermentations and, at the same time, to attempt to increase the protein content as single cell protein. Strains of the yeast Candida lipolytica and the yeast like mold Geotrichum candidum were employed for these investigations. Stickwater fermentations were performed in a laboratory bench top fermentor. Respirometric studies of lipid metabolic activity and microbial observations were periodically performed during these fermentations. Rapid microbial growth and metabolic activity were observed in well aerated cultures. Fermented products were evaluated for chemical composition. Lipid residues were characterized by thin-layer chromatographic procedures. There was evidence of abundant microbial growth, increased lipolytic activity, and decreased lipid content. However, evidence was lacking to show that the protein content of stickwater was actually increased.     

Enzymatic treatment of stickwater from fishmeal industry with the protease from Cucurbita ficifolia

Summary The protease fromC. ficifolia was applied to stickwater prior to evaporation. The evaporator was operated at reduced viscosities with an increase in solid concentration beyond 50% as compared to the untreated substrate.     

C.P.-D.D.-M.A.S. 13C-N.M.R. investigations of anhydrous and hydrated cyclomalto-oligosaccharides: The role of water of hydration

Hydrated and anhydrous cyclomaltohexaose, cyclomaltoheptaose, and cyclomalto-octaose (cyclodextrins) have been investigated by the c.p.-d.d.-m.a.s. ¹³C-n.m.r. technique. The chemical shifts of the signals of C-1 and C-6 provide information about conformation and the results agree fairly well with the earlier scattering data on hydrated systems, but some discrepancies have been found for cyclomaltohexaose. Th conformation of the macro-rings seems to be determined by the hydration water. The unique role of water in forming crystals of cyclomalto-oligosaccharides is demonstrated.     

XXXIV.–Notices of recent Ornithological Publications. An A. B. C. of Common Birds.

[An A. B. C. of Common Birds. A pocket guide to the commoner inland Birds of Britain. Pp. 1–04. Price 6d., by post 7d. Published by the Royal Society for the Protection of Birds, 23 Queen Anne's Gate, S.W.]