Tsutomu Kaneko

Inhibition of bacterial translocation from the gastrointestinal tract of mice injected with cyclophosphamide.

Abstract. Effects of intraperitoneal injection of cyclophosphamide, an immunosuppressant, on the degree of bacterial translocation and morphological changes of Peyers patches (PP) in the intestine were investigated with antibiotic-decontaminated SPF mice and germfree mice monoassociated with Escherichia coli C25. It has been reported that treatment with cyclophosphamide induces bacterial translocation. Cyclophosphamide treatment in this study, however, significantly decreased E. coli C25 translocation from the gastrointestinal tract to the mesenteric lymph nodes (MLN), although the numbers of lymphoid cells, especially B cells, in the PP, MLN, and spleen were remarkably reduced. Four injections of cyclophosphamide at a dose of 100 mg/kg inhibited bacterial translocation more than one injection at a dose of 200 mg/kg in SPF mice. Germfree mice, however, treated with one dose of 200 mg/kg showed the same inhibition of bacterial translocation as those given 100 mg/kg four times. In cyclophosphamide-treated mice, lymph follicles in the PP were obviously smaller than those in control mice, M-cells were similar in appearance to absorption epithelial cells except for short microvilli, and immune cells among the M-cells had disappeared. These data suggested that inhibition of bacterial translocation in mice treated with cyclophosphamide may be the result of morphological and physiological changes of epithelial cells in the gastrointestinal tract, especially M-cells, as a point of entry of invading bacteria, independent of the changes in immunological function.

Improvement of Bread Flavor by a Dairy Substrate Treated with Enzymes and Lactic Acid Bacteria

Iso-amylalcohol (iso-AmOH), iso-butylalcohol (iso-BuOH) and ethylcaprylate (EtOcapry) were the main aroma components in bread, and the content of these components with a dairy substrate treated with several enzymes and fermented with lactic acid bacteria (FCT) increased from 1.2 to 1.6 times those of control bread. The increase in iso-AmOH and iso-BuOH content in bread with FCT appeared due to increased leucine and valine content in dough by adding FCT. The increase in EtOcapry content may have been caused by the caprylic acid found in FCT. The addition of the hydrolysate of milk protein and milk fat to dough is thus shown to greatly improve bread flavor.