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R Katzen

Publications and source records attributed to R Katzen.

11 recordsLinked to original sources

A view of the history of biochemical engineering.

The authors present a view of biochemical engineering by describing their personal interests and experience over the years involving mostly conversion of lignocellulosics into fuels and chemicals and the associated engineering subjects.

Animals↗

Ethanol from lignocellulosic wastes with utilization of recombinant bacteria.

This article presents the advanced technology that has been developed by BioEnergy International of Gainesville, Florida, utilizing novel recombinant strains of bacteria developed by Lonnie Ingram of the University of Florida. The first commercial applications of these unique fermenting organisms convert 5-carbon sugars, as well as 6-carbon sugars, and oligomers of cellulose (e.g., cellobiose and cellotriose) directly to ethanol. The proposed systems that will be utilized for conversion of agricultural wastes, mixed waste papers, and pulp and paper mill waste in forthcoming commercial installations are now under design. This involves the extensive experience of Raphael Katzen Associates International, Inc. in acid hydrolysis, enzyme production, enzymatic hydrolysis, large-scale fermentation engineering, and distillation/dehydration. Specific examples of this advanced technology will be presented in different applications, namely: 1. Conversion of the hemicellulose content of sugar cane bagasse to 5-carbon sugars by mild-acid prehydrolysis, followed by fermentation of the 5-carbon sugar extract with recombinant Escherichia coli in a commercial installation soon to be under construction in Brazil. This unique process utilizes the surplus hemicellulose fraction of bagasse not required for steam and power generation to produce ethanol, additional to that from the original can juice, which has been converted by conventional sucrose fermentation to ethanol. The process also recovers and converts to ethanol the majority of sucrose normally lost with the bagasse fibers. Resultant beer is enriched in an innovative process to eliminate the need for incremental rectification capacity. 2. Application of this technology to mixed waste paper in Florida, with a moderate loading of newsprint (85% mechanical wood fiber), will involve a mild-acid prehydrolysis, the partial extraction of the 5-carbon sugars produced from hemicellulose as a feedstock for propagation of the recombinant Klebsiella oxytoca bacterium. Included is a facility providing for in-house production of cellulase enzyme, as an active whole broth for direct use in simultaneous saccharification and fermentation (SSF) of the remaining cellulose and residual 5-carbon sugars to ethanol. This is followed by distillation and dehydration in the advanced commercially available low-energy recovery system. 3. Another potential application of this unique technology involves utilization of a variety of wastes from several pulp and paper mills in close proximity, permitting collection of these wastes at low cost and reducing the considerable cost encountered in disposing of such low-energy wet waste.(ABSTRACT TRUNCATED AT 400 WORDS)

Cellulose↗

Disappearance of glucagonoma rash after surgical resection, but not during dietary normalization of serum amino acids.

Hypoaminoacidemia and skin rash are features of the glucagonoma syndrome. A glucagonoma patient with earlier insulin treated, noninsulin-dependent diabetes, and functional liver metastases, 3 yr postresection of pancreatic tumor, was treated with a high protein diet for 2 wk, then switched to a high carbohydrate diet for 3 wk followed by 3 wk on high protein diet, which continued for 3 months with additional carbohydrate. While on the high protein diet urine nitrogen indicated frank retention and total plasma amino acid levels normalized each time. Plasma amino acid decreased again after 1 wk on the high carbohydrate diet. Skin rash varied irrespective of amino acid levels, but cleared 4 days after resection of metastases. However, total amino acid did not reach normal levels on a conventional diet 3 wk postsurgery, but were normal 6 wk later. A high protein diet can normalize plasma amino acids and allow nitrogen retention in glucagonoma, apparently overriding the gluconeogenic drive of the high circulating glucagon levels. The skin rash may not be only attributed to hypoaminoacidemia.

Adenoma, Islet Cell↗

Rapid diagnosis of beta-haemolytic streptococcus group B endocarditis by buffy-coat examination and gas-liquid chromatography.

A semicomatose 34-year-old man had fever, heart murmur, and multiple gangrenous lesions. Several blood cultures were negative. Cultures of the heart valve grew beta-haemolytic streptococcus group B. The organism was seen in buffy-coat examination of the venous blood. The gas-liquid chromatogram of the serum was different from those of normal controls and of patients with invasive candida infection; it closely mimicked the one obtained from the organism itself. These studies promise to be valuable diagnostic adjuncts.

Adult↗