Abstract: This invention relates to stabilization of phenylalanine ammonia lyase against proteolytic degradation by chemical modification with crosslinking agents, or by genetic modification, a phenylalanine ammonia lyase variant, a method of preparing the variant and a pharmaceutical composition containing phenylalanine ammonia lyase.

Abstract: Lipase is immobilized by adsorption on a polymethacrylic acid ester resin such as polymethylmethacrylate cross-linked with divinyl benzene. The resin is preferably a particulate, macroporous resin having an average pore radius of 100-200 .ANG., a total surface area of 25-150 m.sup.2 /g and a particle size of 100-1,000 .mu.m. The lipase may be obtained from Mucor miehei, Candida antarctica, Pseudomonas cepacia or Humicola lanuginosa. The immobilized lipase may be dried and is used for interesterifying an ester, hydrolyzing an ester or synthesizing an ester. Interesterification can be carried out continuously in a fixed-bed column.

Abstract: Immobilized lipase is produced by mixing an aqueous lipase solution with a particulate, macroporous, weak anion exchange resin, and recovering and drying the resin having lipase immobilized thereon. The resin has a particle size such that more than 90% resin particles have a size between 100-1000 .mu.m. The immobilized lipase is used in a packed bed for continuous transesterification or solvent free fats. Preferably, the lipase is Mucor miehei lipase.

Abstract: Immobilized lipase is produced by mixing an aqueous lipase solution with a particulate, macroporous, phenolformaldehyde adsorbent resin, and recovering and drying the resin having lipase immobilized thereon. The resin has a particle size such that more than 90% resin particles have a size between 100-1000 .mu.m. The immobilized lipase is used in a packed bed for continuous transesterfication of solvent free fats. Preferably, the lipase is Mucor miehei lipase. The immobilized lipase has on a dry basis at least 10 batch interesterification units (BIU) and at least 500 lipase units (LU).

Abstract: Thermal stability of microbial rennet is reduced by treatment of the rennet in aqueous medium with aliphatic or inorganic peroxy acids or salts thereof. Preferably, the microbial rennet is Mucor Miehei rennet and the peroxy acid is a lower aliphatic peroxy acid such as peracetic acid. The thermally destabilized microbial rennet is inactivated when whey containing the rennet is pasteurized.

Abstract: Microbial rennet such as from Mucor miehei is thermally destabilized by treatment of the rennet in an aqueous medium with oxidizing agents containing active chlorine such as hypochlorites. The thermally destabilized rennet is advantageous for cheese making where absence of rennet activity in pasteurized whey is desired.