Optimization of physicochemical parameters for IndianDosa batter fermentation

Summary Dosa batter fermentation was optimized by employing a variable set of different physicochemical conditions for further raising the nutritional levels. The best combination of these parameters was incubation at 28°C, with initial pH 4.5 and supplementation of the batter with free sugar (sucrose, I-2%).     

Kinetic characteristics of soluble and brush border alkaline phosphatase and sucrase activities in developing rat intestine: effect of hormones

Suckling rat intestine contains 35 and 65% of the cytosolic and membrane-bound alkaline phosphatase (AP) activities. The corresponding values for sucrase were 20 and 80% respectively. The amount of the soluble enzymes was reduced to 7-11% in adult rat intestine. Administration of cortisone, thyroxine or insulin to suckling animals induced adult type distribution of the enzymes. There were apparent differences in kinetic characteristics of soluble and brush border enzymes, but the kinetic properties of the normally developed and hormone-induced AP and sucrase were essentially similar. This suggested identical nature of these enzymes under these conditions. A biphasic Arrhenius plot was obtained for AP in weaned and hormone injected pups with a break point around 18 degrees C, while the soluble enzyme yielded a monophasic curve (Ea = 8-11 kcal/mole). Arrhenius plot for sucrase was monophasic in the suckling, hormone-injected and adult rat intestine (Ea = 8.3-15.1 kcal/mole). Membrane-bound enzymes were generally labile, while soluble enzyme activities were stable to heat treatment (sucrase at 50 degrees C and AP at 60 degrees C) in various experimental groups.     

Chemiluminescent substrates increase sensitivity of antigen detection in western blots

Replacement of colorimetric substrates in Western blots by chemiluminescent reagents enhances the sensitivity of detection by more than an order of magnitude. Protein levels beyond the detection limit of colorimetric substrates can be consistently detected without modifying pre-existing laboratory protocols.     

Application of the Tradescantia micronucleus assay for the genetic evaluation of chemical mixtures in soil and aqueous media.

Genotoxic evaluations of arsenic trioxide, dieldrin, lead tetraacetate and their nine binary and one tertiary mixtures were performed using the Tradescantia micronucleus (Trad-MN) assay. The chemicals or their mixtures were either (1) mixed into soil, and chemical exposure to the target cells was through the roots of intact plants grown in the soil or (2) through plant cuttings in which the inflorescences received treatment by absorption through stem of an aqueous solution of the test chemicals. All three chemicals yielded clastogenic responses when tested in soil medium and only two of these i.e. arsenic trioxide and dieldrin were positive when plant cuttings were exposed to the test chemicals in the aqueous medium. The clastogenicity of the chemical mixtures was modified by the ratio of the individual chemical in a particular mixture and also by the medium in which these mixtures were tested.     

A monochromosomal hybrid cell assay for evaluating the genotoxicity of environmental chemicals

The development and utilization of a monochromosomal hybrid cell assay for detecting aneuploidy and chromosomal aberrations are described. The monochromosomal hybrid cell lines were produced by a two-step process involving transfer of a marker bacterial gene to a human chromosome and then by integration of that human chromosome into a mouse complement of chromosomes through microcell fusion. For chemically induced aneuploidy, the segregation of a single human chromosome among mouse chromosomes is used as a cytogenetic marker. The genetic assay for aneuploidy is based on the ability of the cells to grow in a medium that selects for the loss of the human chromosome. The assay for clastogenicity is based on survival of the cells after treatment with the chemicals in medium that selects for retention of the human chromosome but loss of its segment containing diphtheria toxin locus. The assays greatly simplify the detection of chromosomal aberrations induced by environmental factors at low-dose levels.     

3NTPT: a newly discovered antifertility agent. V. Ovarian dysfunction in Dysdercus koenigii.

A 4 h exposure to a residual film of 15 mg 1-(3-nitrophenyl)-4,4,6-trimethyl-1H,4H-pyrimidine-2-thiol (3NTPT) dissolved in 5 ml acetone significantly inhibited ovarian growth in Dysdercus koenigii. The ovaries of treated females remained small and the trophocytes, the trophic core, the prefollicular tissue and the oogonia completely degenerated. This was followed by degenerative changes in the follicular epithelium, the interfollicular tissue and the developing oocytes. Resorption of the oocytes reduced the vitellarium to an empty tube. The follicular epithelium of the resorbed oocytes protruded into the lumen, while the interfollicular tissue completely degenerated. By day 7 after treatment, the ovaries were completely dystrophic, and this state was not reversible.     

Laccase production and wood degradation byTrametes hirsuta

The laccase production byT. hirsuta was better in lignin as compared to malt extract media. Tannic acid gave the best laccase yield out of different lignins, phenolic compounds and sugars tested as substrates. The sugars proved to be good substrates for growth only. The role ofT. hirsuta in semisolid fermentation of sawdust was studied with reference to its capacity to degrade lignin in its native form. During two months of decay an overall weight loss of 22.2% along with a lignin loss of 13.6% was recorded.