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Mechanical properties of starch‐based supercritical fluid extrusion (SCFX) extrudates were correlated to their structure. Thermosetting ingredients were added to the feed and the extrudate was dried to set the expanded structure. Compared to whey protein concentrate with 34% protein (WPC‐34), addition of egg white (EW) gave a softer skin and a fragile but well formed cellular structure. For drying between 70 and 100 °C, the overall structure was more homogenous for EW added. A higher modulus was associated with a larger number average of sides in a cell face and higher percentage of closed cells. Ashby's model (1983) for non‐food cellular solids gave a good fit to our data for relating relative compressive modulus to relative bulk density. A linear regression model indicated that bulk density alone was a good predictor of mechanical strength.

Supercritical fluid extrusion, a low temperature and low shear process, was used to produce pre-gelatinized corn and potato starch-based extrudates, containing 4–10% thermosetting egg white (EW) or whey protein concentrate (WPC-34), and dried at 22–100°C. Addition of proteins reduced shrinkage of high-moisture extrudates, as indicated by increases in expansion ratio by up to 140 and 341% when the drying temperatures were 22 and 100°C, respectively. Products containing 7% EW or WPC-34 and dried at 85°C expanded best while maintaining an intact structure, with expansion ratio (∼12) and bulk density (∼0.10 g/cm3) comparable to steam extrudates. The products had a unique composite and uniform microcellular structure, with average cell sizes in the range of 50-250 μm and cell density of the order of 106 cells/cm3. The classical nucleation theory and a qualitative model for cell growth and shrinkage based on glass transition temperature were used to explain the microcellular structure.

Bacillus stearothermophilus AN 002 secreted thermostable alkaline amylase into a liquid growth medium containing 2 g/l starch. Amylase activity was highest at early stationary phase of growth. Among the various carbohydrates tested maximum amylase production was obtained with starch. When starch was replaced by other carbon sources, amylase production was reduced. Peptone and corn steep liquor (CSL) were the ideal nitrogen sources for amylase production by this strain. Of the phosphate sources tested, (NH4)2HPO4 showed best restults. Amylase production was highest in a laboratory fermenter at a initial pH of 6.5 and at a constant pH of 7.0. The optimum aeration and agitation for amylase production were 0.66 v/v/m and 400 rev/min, respectively. Maximum growth was obtained at 55 °C and maximum amylase was produced at 50 °C. The amylase was found to be stable between pH 6.0 to 11.0.

Immobilized yeast cells in agar gel beads were used in a packed bed reactor for the production of ethanol from cane molasses at 30°C, pH 4.5. The maximum productivity, 79.5g ethanol/l.h was obtained with 195g/l reducing sugar as feed. Substrate (64.2%) was utilized at a dilution of 1.33h-1. The immobilized cell reactor was operated continuously at a constant dilution rate of 0.67h-1 for 100 days. The maximum specific ethanol productivity and specific sugar uptake rate were 0.610g ethanol/g cell.h and 1.275g sugar/g cell.h, respectively.

Saccharomyces cerevisiae cells were immobilized in agar gel and used in a tubular reactor for conversion of cane molasses to ethanol at 30 degrees C, pH 4.5. Reactor was used in a continuous operation to test the operational stability and ethanol productivity. After 100 days of continuous fermentation at a dilution rate of 0.67 hr-1, some deactivation of cells was observed, but ethanol productivity was recovered by reactivating the cells by sparging air intermittently. It was found that intermittent reactivation during continuous operation was very important for satisfactory performance of the reactor. During operation, gel beads maintained their rigidity. Maximum ethanol concentration (94.9 g/L) was obtained with a feed containing 255 g/L reducing sugar, at a dilution rate of 0.2 hr-1. Maximum volumetric productivity (79.5 g ethanol /L/hr), specific ethanol productivity (0.58 g ethanol/g cells/hr), specific sugar uptake rate (1.12 g sugar/g cells/hr) and ethanol yield coefficient (0.43 g ethanol/g sugar) were obtained with a feed containing 195 g/L reducing sugar at a dilution rate of 1.33 hr-1.

Preliminary random and mass blood surveys undertaken between 2000-0100 h in a tea garden of Upper Assam revealed more than 8 per cent positivity for microfilaria (mf) of Wuchereria bancrofti. The mf carriers were considerably high among males (73) as compared to females (48). Culex quinquefasciatus was incriminated as a vector with man hour density of 68.5 in human dwellings (indoors). The detection of mf in children who had never moved from the area and filaria larvae in vector mosquitoes collected from human dwellings indicate that indigenous transmission is going on in the garden and that filariasis has become a local health problem.

The synthesis and localization of α-amylase were studied in Bacillus stearothermophilus AN002 at 40, 45, 50 and 55 °C and also during early exponential, late exponential and stationary phases of growth. The extracellular α-amylase synthesis was highes at 50 °C and at stationary growth phase. Accumulation of intracellular α-amylase was observed in cells grown at 40 °C and was distributed in all the cell fractions. At 50 and 55 °C the cell did not have α-amylase in the protoplasm or protoplamic membrane. The synthesis and externalization of extracellular enzyme are two processes and the externalization is controlled by growth temperature and cell age.

The influence of growth temperature, media composition and cell age on the chemical composition of Bacillus stearothermophilus strain AN 002 has been determined. The total cellular protein decreased and the free amino acid content increased with growth temperature, in both exponential and stationary growth phase. The protein and free amino acid contents of cells were higher in the stationary phase than in the exponential phase, irrespective of growth temperature and media composition. The RNA content was only reduced in cells grown at 55 degrees C. No significant variations were observed in the DNA and carbohydrate contents with respect to growth temperature and cell age. The total lipid and fatty acid compositions on the other hand varied as a function of growth temperature, cell age and media composition. Differences in the relative concentrations of even, odd and branched chain fatty acids were noticed. No variation was observed in the antiiso and unsaturated fatty acids with respect to growth temperature. The unique variations in the fatty acid composition and total lipids at the growth temperature of 50 degrees C and their variations in the stationary growth phase seem to be characteristic for B. stearothermophilus AN 002.

Saccharomycopsis fibuligera ST 2 produced high levels of extracellular amylase during the stationary phase of growth. Glucose or other low molecular weight metabolizable sugars did not repress the synthesis of the amylase, indicating the lack of catabolite repression in this organism. Of the nitrogen sources examined, yeast extract and corn steep liquor stimulated the highest yield of amylase. Ammonium sulphate inhibited α-amylase synthesis. The enzyme was purified 118-fold from the culture supernatant fluid by isopropanol precipitation and DEAE-Sephadex A50 chromatography. The purified enzyme was characterized as an α-amylase. The α-amylase had the following properties: molecular weight, 40900 ± 500; optimum temperature, 60°C; activation energy, 1600 cal/mol; optimum pH, 4·8–6·0; range of pH stability, pH 4·0–9·4; Km (50°C, pH 5·5) for soluble starch, 0·572 mg/ml; final products of starch hydrolysis—glucose, maltose, maltotriose and maltotetraose.

Relief of dysphagia is the main aim in the management of advanced oesophageal carcinoma. Ninety three patients were treated with insertion of Mousseau Barbin tube after laparotomy. Seventeen patients died during immediate post operative period. Forty five patients were free from dysphagia and lived upto 1 year, 4 upto 1 1/2 years and 1 upto 2 years. Twenty patients were lost follow up. Complications occured in twenty eight patients. 6 had haematemesis, 7 pulmonary infection, 3 blockage of tube, 2 displacement of tube and 10 developed wound infection.

Bacillus megaterium, in which sporulation was blocked either by mutation or with netropsin, synthesizes during the stationary phase more exocellular proteinase than the sporulating culture. The asporogenic mutant synthesizes the enzyme at a higher rate and for a longer time than does the sporulating population. The culture, whose sporulation was inhibited by netropsin, produces the proteinase at a higher rate, although for only a limited time interval.