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Biomedical subjects

R P Tengerdy

Publications and source records attributed to R P Tengerdy.

At least 19 recordsLinked to original sources
PubMed2003

Optimization of phytase production by solid substrate fermentation.

The production of phytase by three feed-grade filamentous fungi ( Aspergillus ficuum NRRL 3135, Mucor racemosus NRRL 1994 and Rhizopus oligosporus NRRL 5905) on four commonly used natural feed ingredients (canola meal, cracked corn, soybean meal, wheat bran) was studied in solid substrate fermentation (SSF). A. ficuum NRRL 3135 had the highest yield [15 IU phytase activity/g dry matter (DM)] on wheat bran. By optimizing the supplementation of wheat bran with starch and (NH(4))(2)SO(4), phytase production increased to 25 IU/g DM. Optimization was carried out by Plackett-Burman and central composite experimental designs. Using optimized medium, phytase, phosphatase, alpha-amylase and xylanase production by A. ficuum NRRL 3135 was studied in Erlenmeyer flask and tray SSF. By scaling up SSF from flasks to stationary trays, activities of 20 IU phytase activity/g DM were reproducibly obtained.

6-Phytase↗
PubMed2001

Enzyme assisted ensiling of alfalfa with enzymes by solid substrate fermentation.

A crude enzyme preparation, obtained by solid substrate fermentation (SSF) with a Gliocladium spp. and added at the 5% level to wilted or non-wilted alfalfa, improved the fermentation characteristics and stability of alfalfa silages as effectively as commercial preparations, Novo-Nordisk Celluclast 1.5 L and Viscozyme 120 L, applied at the 0.025% level. The effective dose of the crude enzyme costs about one-fourth of the cost of the commercial enzymes.

Carbohydrate Metabolism↗
PubMed1998

Perspectives in agrobiotechnology.

This review surveys the most important and promising contributions of agricultural biotechnology to the development of sustainable, environment-friendly agriculture. It deals with the recent achievements of genetic technology for the development of new transgenic microbial, plant and animal products. It also deals with the newest developments and perspectives of microbial intervention in agricultural practices, such as biofertilizers, biocontrol agents, and various microbiological products used in modern agriculture. The review surveys the outlook for a waste-free, environment-friendly sustainable agricultural practice, including waste management, recycling and bioremediation technologies. The review lists the most important marketable agrobiotechnological products, and their present and projected sales volume.

Agriculture↗
PubMed1996

Bioprocessing of sweet sorghum with in situ-produced enzymes.

Enzyme-assisted ensiling (ENLAC), using in situ-produced enzymes from Gliocladium sp. TUB-F-498, preserved 80% of the sugar content of sweet sorghum, and facilitated its extraction by countercurrent diffusion. The in situ enzyme was produced on the extracted sweet sorghum pulp by an 8-d solid substrate fermentation (SSF) with a yield of 4.6 cellulase and 400 IU/g dry wt xylanase. Two percent of the fermented substrate had cellulase and xylanase levels equivalent or superior to levels found in the commercial enzymes Celluclast and Viscozyme Novo at the 0.025% application level in ENLAC. The in situ-production of enzymes on recyclable substrates may reduce bioprocessing costs significantly. In this ENLAC process, the cost of the in situ enzymes is estimated to be about $0.12/MT substrate, compared to $9.5/metric ton (MT) for the commercial enzymes, a cost reduction of nearly 80-fold.

Biotechnology↗
PubMed1991

Serological responses of rams to a Brucella ovis-vitamin E adjuvant vaccine.

Rams which were vaccinated at 6-8 months of age with a water-in-oil Brucella ovis-vitamin E adjuvant vaccine had significantly higher serum antibody levels than rams vaccinated with a commercial B. ovis bacterin or B. melitensis Rev 1. The adjuvant vaccine did not cause abscesses at the site of injection as some water-in-oil emulsions do. Two years after vaccination, the vitamin E adjuvant-vaccinated rams had higher antibody level than the other groups. This was most likely due to a secondary response to naturally occurring infection with B. ovis.

Adjuvants, Immunologic↗
PubMed1991

Vitamin E adjuvant formulations in mice.

Water-in-oil-type adjuvants prepared with natural or synthetic vitamin E as the oil phase, Arlacel A or Montanide 103 as emulsifier and 1.0% aqueous solution of bovine serum albumin (BSA) as antigen were tested in mice. An emulsion of 0.42 ml vitamin E, 0.42 ml special mineral oil, 0.15 ml Arlacel A and 1.0 ml BSA gave maximal humoral response, but 0.85 ml special mineral oil, 0.15 ml Arlacel A and 1.0 ml BSA (standard Freund's incomplete adjuvant formulation) gave the greatest delayed-type hypersensitivity response.

Adjuvants, Immunologic↗
PubMed1990

The role of vitamin E in immune response and disease resistance.

Vitamin E supplementation enhances humoral and cell-mediated immunity, and augments the efficiency of phagocytosis in laboratory animals, farm animals, and humans. In its disease protection effect vitamin E interacts with other antioxidant nutrients and with other nutrients in the diet. Other antioxidant nutrients, such as vitamin A and beta carotene, also enhance disease resistance. Beta carotene is effective in combination with vitamin E. The optimal dose of vitamin E for maximum protection depends on many factors; thus it has to be established case by case. The delivery system of vitamin E greatly influences its effectiveness. A targeted delivery to localized immunocompetent cells in adjuvant formulations is far more effective than a general dispersed delivery in a diet. Vitamin E adjuvants provided greater immunoprotection against enterotoxemia and epididymitis in sheep than conventional vaccines.

Adjuvants, Immunologic↗
PubMed1989

Vitamin E, immune response, and disease resistance.

Vitamin E as a dietary supplement or as part of an adjuvant vaccine formulation increases humoral and cell-mediated immunity and disease resistance in laboratory animals, farm animals, and humans. Adjuvant administration has far greater effect than dietary supplementation. Vitamin E as an antioxidant protects the cells of the immune response from peroxidative damage; possibly through a modulation of lipoxygenation of arachidonic acid, vitamin E alters cell membrane functions and cell-cell interactions. The most pronounced effect of vitamin E is on immune phagocytosis. Dietary supplementation is beneficial to animals, especially under stress, in decreasing susceptibility to infections. Vitamin E adjuvant vaccines have provided greater immunoprotection against enterotoxemia and epididymitis in sheep than conventional vaccines.

Adjuvants, Immunologic↗
PubMed1987

Isolation and antigenic reactivity of Brucella ovis outer membrane proteins.

Brucella ovis cell membranes were isolated from fractured and lysozyme-treated cells by ultracentrifugation. These preparations appeared to consist largely of outer membranes, as judged from the results of ultracentrifugation experiments in sucrose density gradients under conditions that are widely used to separate inner and outer membranes of gram-negative bacteria. The sequential detergent extraction of cell membranes yielded mainly lipopolysaccharide and three groups of outer membrane proteins. In immunoblotting, lipopolysaccharide had good antigenic reactivity with all sera from rams exposed to B. ovis (vaccination or natural infection), but some outer membrane proteins reacted strongly only with sera from immune (vaccinated) rams, not from infected rams, suggesting a possible diagnostic role for such proteins in predicting immunity or infection.

Animals↗
PubMed1986

Immune response in rams experimentally infected with Brucella ovis.

Cellular as well as humoral immune responses were detected in six rams experimentally infected with Brucella ovis. Specific antibodies were detectable by enzyme-linked immunosorbent assay by day 11 after infection in all the rams. The levels of IgM antibodies and total antibodies in the serum rose until 33 and 41 days after infection respectively, then levelled off. Antigen-induced blastogenic responses by lymphocytes developed as early as five days after infection in all rams but had decreased to low levels by day 63 in most. Blastogenesis induced by phytohaemagglutinin and concanavalin A varied among infected rams and did not differ significantly (P greater than 0.05) from control rams. All rams had developed delayed-type skin hypersensitivity by day 63 after infection. One ram which did not become infected as a result of exposure had low levels of B ovis serum antibodies and a detectable antigen-induced lymphocyte blastogenic response before infection, suggesting the involvement of cell-mediated immunity in protection against B ovis.

Animals↗
PubMed1984

Protection of rams against epididymitis by a Brucella ovis-vitamin E adjuvant vaccine.

Rams vaccinated at 7 and 8 months of age with a B. ovis-vitamin E adjuvant vaccine had increased antibody titers compared with Freund's incomplete adjuvant or commercial bacterin vaccinated rams. The percent overall infectivity in an experimental infection of B. ovis-vitamin E adjuvant vaccinated rams was 22% compared to 44% for B. ovis-Freund's incomplete adjuvant or bacterin vaccinated rams and 67% for control.

Adjuvants, Immunologic↗
PubMed1984

Characterization of Brucella ovis lipopolysaccharide and its use for diagnosis of ram epididymitis by enzyme-linked immunosorbent assay.

Rough lipopolysaccharide, extracted by a mixture of phenol, chloroform, and petroleum ether from freeze-dried Brucella ovis cells with a yield of 0.71%, contained relatively small amounts of protein and nucleic acid contaminants as compared with lipopolysaccharides from other Brucellae. The crude lipopolysaccharide was suitable as a diagnostic antigen in an enzyme-linked immunosorbent assay for the sensitive and specific detection of ram epididymitis caused by B. ovis infection. In comparative serological tests, the enzyme-linked immunosorbent assay with B. ovis lipopolysaccharide gave better identification of infections and fewer false-negative results than the enzyme-linked immunosorbent assay with sonicated antigen or the complement fixation test.

Animals↗
PubMed1981

Vitamin E and aspirin depress prostaglandins in protection of chickens against Escherichia coli infection.

The hypothesis was tested that vitamin E protects chickens from a lethal Escherichia coli infection by inhibiting the biosynthesis of prostaglandins, thereby activating humoral immunity and phagocytosis. When chickens were fed supplement vitamin E at the level of 300 mg/kg diet, which is six times the presently used dietary level, endogenous PGE1, PGE2, and PGF2 alpha levels decreased in the immunopoietic organs, bursa, and spleen. Antibody titers to E. coli lipopolysaccharide and phagocytosis increased at the same time. Infection slightly increased prostaglandin levels and vitamin E appeared to compensate for this increase. Aspirin, a known prostaglandin inhibitor acted synergistically with vitamin E in depressing endogenous PG levels in bursa and decreasing mortality from E. coli infection.

Animals↗
PubMed1977

Effect of vitamin E and A on humoral immunity and phagocytosis in E. coli infected chicken.

Dietary supplementation of either vitamin E (300 mg./kg. diet) or vitamin A (60,000 I.U./kg. diet) significantly reduced E. coli caused mortality, but the combination of the two vitamins did not. Protection was attributed to increased antibody production and increased phagocytosis, although neither factor alone gave a significant correlation with mortality. Vitamin E level significantly increased especially in the spleen of supplemented chicks, but vitamin A suppressed this increase, partially explaining the lack of protection in vitamin E and A supplemented chicks.

Animals↗
PubMed1975

Vitamin E or vitamin A protects chickens against E. coli infection.

The supplementation of either vitamin E (300 mg./kg. diet) or vitamin A (60,000 I.U./kg. diet) to a standard chick ration increased the protection of six week old immunized chickens against E coli infection, decreasing mortality from about 40% to 5%. The combination of the two vitamins, however, did not give as much protection as either vitamin alone. Vitamin E or A did not protect chicks from weight loss and severe morbidity due to infection, but slightly increased the rate of recovery.

Animals↗