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Biomedical subjects

K G Newton

Publications and source records attributed to K G Newton.

15 recordsLinked to original sources
PubMed1982

Effect of lactic acid concentration on growth on meat of Gram-negative psychrotrophs from a meatworks.

The inhibitory effect of the lactic acid in meat on gram-negative psychrotrophs appears to be due mainly to the decrease in pH, not to action of the undissociated acid. Species of Pseudomonas were essentially unaffected by the pH of normal meat. Other gram-negative psychrotrophs isolated from a meatworks included a large number of strains which would not grow on meat of normal pH at chill temperatures. Raising either the pH or the incubation temperature allowed many of the pH-sensitive strains to initiate growth. However, the growth rates of pH-insensitive strains were not affected by increasing the pH, and there were no significant differences in the composition of the spoilage floras which developed on chilled meat of normal and high pH.

Bacteria↗
PubMed1980

Development of bacterial spoilage at adipose tissue surfaces of fresh meat.

Adipose tissue contains low-molecular-weight soluble substances which are utilized in preference to lipid for bacterial growth. These components are present in low concentration at the surface of adipose tissue, and the pH of the surface is high (greater than 7.0). Bacteria growing on a thin layer of agar over an adipose tissue surface utilized glucose preferentially, but this was soon exhausted in the vicinity of colonies. Amino acids were then attacked, producing malodorous substances which were detectable as spoilage odors when the cell density was about 10(6)/cm2. Growth ceased at a cell density approaching 10(8)/cm2 because of substrate limitation. Bacterial lipolytic activity is not necessary for the development of bacterial spoilage of adipose tissue.

Adipose Tissue↗
PubMed1979

Spoilage of vacuum-packaged dark, firm, dry meat at chill temperatures.

The flora of vacuum-packaged dark, firm, dry meat included thred organisms not usually found on vacuum-packaged meat, Yersinia enterocolitica, Enterobacter liquefaciens, and Alteromonas putrefaciens. Y. enterocolitica did not affect the meat quality. Production of spoilage odors by E. liquefaciens could be prevented by addition of glucose or citrate to the meat. Greening of meat could be prevented by addition of glucose or citrate to the meat. Greening of meat by A. putrefaciens was not prevented by addition of glucose, as the organism degraded cysteine with the release of H2S even when glucose was present. To prevent greening, growth of A. putrefaciens must be inhibited by reducing the meat pH to less than 6.0.

Anaerobiosis↗
PubMed1978

Storage quality of dark, firm, dry meat.

Dark, firm, dry meat contains little or no glucose. Therefore, spoilage bacteria growing on such meat immediately attack amino acids so that spoilage odors and ammonia are detectable at comparatively low cell densities (about 10(6)/cm2).

Ammonia↗
PubMed1977

Coliforms from hides and meat.

Coliform tests were performed on 85 hide and 75 meat samples. IMViC reactions were determined on isolates from positive confirmed and fecal tests, and strains other than Escherichia coli were identified. Strains typed as Aerobacter aerogenes types I and II were identified as Enterobacter cloacae (51.4%), Klebsiella pneumoniae (21.5%), Enterobacter aerogenes (15%), and Enterobacter liquefaciens, Serratia, and unidentified coliforms (12.1%). K. pneumoniae appeared to be responsible for less than 1% positive fecal tests.

Enterobacter↗
PubMedDate not supplied

The biology of aging (JARA): an ayurvedic approach.

Ayurveda considers Rasāyana as one of the foremost branches of Astānga Ayurveda and have rightly justifies its status by the place its given in the Ayurvedic treatises. The word Rasāyana should not be mistaken as a therapy exclusively related to old age. It can be applied from pediatrics to geriatrics. Suśruta defies Rasāyana as a measure, which prolongs and provides positive health, improves mental faculties and provides resistance and immunity against diseases. Caraka states that the means of obtaining optimum nourishment to the Dhātus are called Rasāyanas. This paper is dealt in two ways - components, which accelerate or trigger an early onset of aging and measures adopted to reverse them.

Aging↗