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A study was carried out on the causes of liquefaction of tamarind kernel (TK) paste used in jute warp sizing. Mill- decomposed pastes, added as inocula to fresh paste, strongly liquefied the latter under aerobic as well as crudely anaerobic conditions. Aerobic bacteria isolated from mill pastes were mostly unable to liquefy, either singly or jointly. On the other hand, 9 of the 11 fungal species tested (some isolated from mill pastes) caused strong liquefaction. The enzymes in the crude filtrates of some of these liquefied TK paste at a faster rate than mineral acids at boil. In laboratory experi ments simulating mill conditions of sizing, these results were generally confirmed, fungal action being much stronger than bacterial. Aspergillus fumigatus and its enzyme were the most potent. Accumulated fungal enzymes appear to be the chief cause of liquefaction in mills. While the strongly liquefying fungi could be inhibited by small doses of common antiseptics, these had little effect on their enzymes. Sodium sulfide at 0.16% concentration inhibited all these enzymes.

Exposure to heat, light, acids and alkalis was found to render jute more resistant to attack by aerobic bacteria. The resistance imparted by the physical agencies appears to be due to the formation of decomposition products, apparently from the non-cellulosic portion, while tho chemical agencies seem to contribute to resistance by removing some micro- and possibly macro-nutrients.

Chaetomium brasiliensis requires aneurin for growth, and calcium (strontium or barium), aneurin and a low nutrient level for the formation of ascospores. Decreasing suboptimal doses of calcium progressively decrease the number of fertile perithecia until none is formed, the average perithecial size is reduced, but not the total number of perithecia. Above the optimum level, calcium delays formation of perithecia and ascospores and, ultimately, spore germination; it has no favourable effect on vegetative growth. The fungus appears able to synthesize aneurin slowly after growth is complete.

The decomposition of jute and cellulose by aerobic bacteria from soil has been investigated. Bacterial decomposition of jute is rapid under aerobic conditions only when the fibre is actually wet. The mean optimum temperature for the growth of these bacteria is near 37°C and the optimum pH is near the neutral region. Jute leached in hot water is more resistant to bacterial attack owing to the removal of micro-nutrients. Lignin is not only the most resistant constituent of jute, but it also offers some protection to the cellulosic fraction of the fibre. Hemicellulose is the most easily assimilable major fraction of jute and its presence also leads to increased consumption of α-cellulose. However, about 25% of the xylan content of jute is as resistant to bacterial attack as the α-cellulose fraction. Jute α-cellulose occupies an intermediate position between cotton α-cellulose and filter paper in susceptibility to attack. Bacterial decomposition of cellulose appears to be favoured by increase in surface and a...

The vertebral abnormalities in this case were limited to the thoracic region. The defect in fusion of the laminae of the fourth thoracic vertebra could not be visualised properly, though was evident clinically. The parents and other siblings of the case did not reveal any abnormality on clinical examination, but they could not be persuaded to have roentgenological investigations, so hereditary influence could not be studied. The deformity was less obvious in infancy but became more apparent as the child grew up.

SUMMARY: The influence of certain carbohydrates, nitrogen compounds and accessory substances on the growth and sporulation of Chaetomium globosum and Memnoniella echinata has been studied. It has been confirmed that M. echinata needs an external supply of biotin, which has also a slight effect on the growth of Chaetomium globosum. For C. globosum, a very low level of soluble sugar in the medium was essential for the production of perithecia. With adequate biotin, Memnoniella echinata sporulated in the presence of considerable concentrations of sugar, but at low biotin levels no sporulation occurred until soluble sugar approached exhaustion. Jute extract stimulated growth and accelerated sporulation of Chaetomium globosum; this was not due to the presence in the extract of any of nine well-known B-group vitamins. Jute extract had no more influence on Memnoniella echinata than would be due to its biotin content.

A case having multiple sagittal cleft or “butter-fly” vertebrae and hemivertebrae is presented. The record of such coincidence of two rare anomalies in one case could not be found in the literature. Roentgenological investigations of parents and siblings could possibly throw some more light on the case.

(1948). FUNGAL DECOMPOSITION OF JUTE FIBRE AND CELLULOSE: Part 2—The Effect of Some Environmental Factors. Journal of the Textile Institute Transactions: Vol. 39, No. 7, pp. T237-T248.

SUMMARY: The effect of temperature and some chemical substances on the fruiting of strains of nine species of Chaetomium was studied. The optimum temperature for fruiting was generally lower than that for growth. Micro-nutrients of the nature of growth factors and starvation with respect to nutrients may both stimulate fruiting, whereas staling inhibits it, the ultimate balance between these effects determining the fruiting behaviour of a given species. These factors had no significant effect on the final amount of the vegetative growth within the conditions of the experiments.

One hundred and twenty cases of polyradiculoneuropathy (Landry-Guillain-Barre-Strohl syndrome between the ages of 1 and 17 years have been studied. The maximum number of cases (46 cases or 38.33 per cent) occurred in the age group of 3 to under 6 years. Males were more frequently affected than females., The pattern of involvement was predominantly ascending in nature. The distal group of muscles were observed to be more frequently affected than the proximal muscles. The protein content of the C.S.F. ranged between 60 and 620 mg. per cent in this series. Ninety two patients have recovered fully so far. Of them 80 patients recovered within one year. Forty patients were found to be suffering from ascariasis as well and a further probe on the possible role of ascariasis seems desirable.

Growth of a Corticium species on jute fabric exposed to 100% relative humidity led to staining and deterioration of the fiber, showing evidence of considerable oxalic acid production and cellulase activity. Pure oxalic acid in excess of quantities produced by the organism did not degrade jute fabric to any comparable extent, and decomposition of cotton cloth was even less pronounced. Strength losses of jute and cotton yarn as a result of treatment with the cell-free culture filtrate were greater by far than those caused by the autoclaved filtrate, again suggesting cellulase action rather than oxalic acid as the main cause for deterioration.When the fungus was grown on jute and cotton fabrics suspended in a nutrient solution, losses in fabric strength were lower.Filter paper suffered a very small loss in weight when used as substrate for growth. The cellulase appeared to be random-splitting, adaptive, and extracellular in character, showing optimum activity at pH 4.0 and temperature 58 °C.

Pycnidiophora dispersa Clum was isolated from jute and found to be a strong decomposer of this fiber, but not of pure cellulose. The effect of certain carbohydrates, nitrogen compounds, trace elements, and accessory growth factors as well as pH and temperature on the growth and perithecia formation of this fungus was studied. None of the carbohydrates tested gave appreciable growth or perithecia formation in liquid medium, but an initial low concentration of each produced both when tested on solid medium. Of the nitrogen compounds tested only peptone had any effect, which was probably caused by impurities. Pure vitamins and trace elements induced neither growth nor fruiting. Malt extract, yeast extract, and the culture filtrate of an Actinomyces sp. all stimulated growth and fruiting. The filtrate factor and malt extract factor were found to be insoluble in organic solvents, heat-resistant, and adsorbed by charcoal.

Special media suitable for the isolation of fungi growing on jute were developed. Species that would better resist sunlight, such as organisms with dark hyphae and spores or closed fruit bodies, predominated on weather-exposed fabrics. Several strongly cellulolytic organisms not previously implicated in fiber decomposition were isolated from this source. On the other hand, the fungi obtained from jute materials damaged in storage were mostly of the familiar types. Most of the newly isolated fungi are generally missed on ordinary media, but they probably play an important role in the natural decomposition of jute materials.

SUMMARY: The effect of certain carbohydrates, nitrogen compounds and accessory growth factors on the growth and sporulation of several strains of Penicillium vermiculatum and P. wortmanni, as well as of many commonly occurring non-perithecial species, was studied. An initial low concentration of soluble sugar was conducive to perithecial formation in the two sexual species, and perithecial growth was best with polysaccharides as carbon source. Peptone was the most favourable nitrogen source; asparagine exerted an inhibitory effect in many cases. Of six B-group vitamins tested only thiamine had any marked effect. Similar effects of the nutritional factors were seen with the non-perithecial species generally.

SUMMARY: Calcium is required by Chaetomium globosum for the normal formation of perithecia, but is not essential for vegetative growth. Calcium is at least partly replaceable by scrontium or barium. Most of the other species of Chaetomium tested responded to calcium, either in fruiting or growth, or both. Suitable doses of calcium reproduce in a large measure the previously observed effect of jute extract on the fruiting of Chaetomaum species. The presence of calcium in jute extract was established.

SHAKING in some form or other is often resorted to during the incubation of enzymes with their substrates in order to obtain uniformity of results and a high rate of enzyme activity. In studies with insoluble cellulosic substrates this has been the usual practice among various workers. However, in an investigation of the cellulolytic activities of the culture filtrates of some fungi, preliminary experiments indicated that no advantage was to be gained by shaking, either in uniformity or in rate of enzyme activity, and that shaking might actually be harmful. Some of these experiments are summarized below; fuller details will be published elsewhere.

(1962). A Comparison between Tensile Strength and Bursting Strength as Criteria in Assessing Rot-resistance of Jute Fabric. Journal of the Textile Institute Transactions: Vol. 53, No. 12, pp. T577-T578.