Effects of Doenjang, a Traditional Korean Soybean Paste, with High-Salt Diet on Blood Pressure in Sprague-Dawley Rats.

Fermented foods in Korea contain a lot of salt. Although salt is reported to exacerbate health trouble, fermented foods have beneficial effects. We hypothesized that doenjang could reduce blood pressure in Sprague-Dawley (SD) rats fed a high-salt diet. Eighteen SD rats were divided into three groups: normal-salt (NS) group, high-salt (HS) group, and high-salt with doenjang (HSD) group. The salinity of doenjang and saltwater was adjusted to 8% using Mohr's method. Blood pressure was significantly reduced in the HSD group compared with the HS group. Water intake and urine excretion volume has significantly increased in the HS group compared with the HSD group. The excreted concentrations of urine sodium, urine potassium, and feces potassium significantly increased in the HSD group compared with the HS and NS groups. Renin level was significantly decreased in the HSD group compared to the other groups. These results indicate that eating traditional salty fermented food is not a direct cause of hypertension, and the intake of doenjang in normal healthy animals improved blood pressure.

An aerobic detoxification photofermentation by Rhodospirillum rubrum for converting soy sauce residue into feed with moderate pretreatment.

This paper reports an effective process for converting soy sauce residue into feeds by combining moderate acid hydrolysis and ammonization with Rhodospirillum rubrum fermentation. After pretreatment with dilute sulfuric or phosphoric acid (1%, w/w) at 100 °C, materials were subjected to fermentation under several gases (N2, CO2, and air) and different light intensities in a 2-L fermentor. Following sulfuric acid treatment, the true protein increased from 188 to 362 g kg-1 and the crude fiber decreased from 226 to 66 g kg-1 after fermentation at 0.5 L min-1 L-1 of air flow and a light intensity of 750 lx and following phosphoric acid treatment, the true protein increased by 90% and the crude fiber decreased by 67% after fermentation at 0.6 L min-1 L-1 of air flow and a light intensity of 600 lx Other contents, including crude fat, crude ash, phosphorus, sulfur, sulfur-containing amino acids, sodium chloride, and calcium, were also improved for use as feed. Meantime, some toxic substances, including furfural, hydroxymethylfurfural (5-HMF), acetic acid, phenol, and cresol, which were produced by the pretreatments, could be removed by 12-32, 5-8, 49-53, 7-8, and 7-8%, respectively; and total sugars, glucose, and xylose could be utilized by 68-69, 71-72, and 63-67% respectively. The quality of soy sauce residue is improved for use as feed and some toxic substances can be decreased via the R. rubrum fermentation.

Surfactins in natto: the surfactin production capacity of the starter strains and the actual surfactin contents in the products.

Surfactin-type lipopeptides are suspected of being implicated in the rare food poisonings caused by Bacillus species outside the Bacillus cereus cluster. In order to get information on surfactin levels in actual human foods, bacilli from three commercial samples of a Japanese traditional bean product, natto, were isolated in order to clarify their potential to produce the suspect lipopeptides. The isolated bacilli were characterized as Bacillus subtilis. They were ß-hemolytic and gave a positive signal in the PCR screen for genes associated with surfactin production, and their culture extracts were cytotoxic to boar sperm cells. Organic extracts of both Bacillus cultures and the natto samples were analyzed for their surfactin content using ultrahigh-performance liquid chromatography with high-resolution mass spectrometry. All the strains proved to be surfactin producers (15 to 39 µg/ml culture medium); the natto samples contained as much as 2.2 mg g(-1) of surfactins. This means that consumers can ingest at least approximately 80 to 100 mg of surfactins per single 50-g natto serving apparently without suffering any ill effects, indicating a very low human toxicity.

Testicular development in male rats is sensitive to a soy-based diet in the neonatal period.

Approximately 30% of infants in the United States are exposed to high doses of isoflavones resulting from soy infant formula consumption. Soybeans contain the isoflavones genistin and daidzin, which are hydrolyzed in the gastrointestinal tract to their genistein and daidzein aglycones. Both aglycones possess hormonal activity and may interfere with male reproductive development. Testosterone, which supports male fertility, is mainly produced by testicular Leydig cells. Our previous studies indicated that perinatal exposure of male rats to isoflavones induced proliferative activity in Leydig cells and increased testosterone concentrations into adulthood. However, the relevance of the neonatal period as part of the perinatal window of isoflavone exposure remains to be established. The present study examined the effects of exposure to isoflavones on male offspring of dams maintained on a casein-based control or whole soybean diet in the neonatal period, that is, Days 2 to 21 postpartum. The results showed that the soybean diet stimulated proliferative activity in developing Leydig cells while suppressing their steroidogenic capacity in adulthood. In addition, isoflavone exposure decreased production of anti-Müllerian hormone by Sertoli cells. Similar to our previous in vitro studies of genistein action in Leydig cells, daidzein induced proliferation and interfered with signaling pathways to suppress steroidogenic activity. Overall, the data showed that the neonatal period is a sensitive window of exposure to isoflavones and support the view that both genistein and daidzein are responsible for biological effects associated with soy-based diets.

NTP-CERHR monograph on Soy Infant Formula.

Soy infant formula contains soy protein isolates and is fed to infants as a supplement to or replacement for human milk or cow milk. Soy protein isolates contains estrogenic isoflavones ("phytoestrogens") that occur naturally in some legumes, especially soybeans. Phytoestrogens are non-steroidal, estrogenic compounds. In plants, nearly all phytoestrogens are bound to sugar molecules and these phytoestrogen-sugar complexes are not generally considered hormonally active. Phytoestrogens are found in many food products in addition to soy infant formula, especially soy-based foods such as tofu, soy milk, and in some over-the-counter dietary supplements. Soy infant formula was selected for evaluation by the National Toxicology Program (NTP) because of the: (1)availability of large number of developmental toxicity studies in laboratory animals exposed to the isoflavones found in soy infant formula (namely, genistein) or other soy products, as well as a number of studies on human infants fed soy infant formula, (2)the availability of information on exposures in infants fed soy infant formula, and (3)public concern for effects on infant or child development. The NTP evaluation was conducted through its Center for the Evaluation of Risks to Human Reproduction (CERHR) and completed in September 2010. The results of this soy infant formula evaluation are published in an NTP Monograph. This document contains the NTP Brief on Soy Infant Formula, which presents NTP's opinion on the potential for exposure to soy infant formula to cause adverse developmental effects in humans. The NTP Monograph also contains an expert panel report prepared to assist the NTP in reaching conclusions on soy infant formula. The NTP concluded there is minimal concern for adverse effects on development in infants who consume soy infant formula. This level of concern represents a "2" on the five-level scale of concern used by the NTP that ranges from negligible concern ("1") to serious concern ("5"). This conclusion was based on information about soy infant formula provided in the expert panel report, public comments received during the course of the evaluation, additional scientific information made available since the expert panel meeting in December 2009, and peer reviewer critiques of the draft NTP Brief by the NTP Board of Scientific Counselors on May 10, 2010.

A soy diet accelerates renal damage in autoimmune MRL/Mp-lpr/lpr mice.

Isoflavones, which are phytoestrogens present in large quantities in soy and soy-derived products, have estrogenic activity, inhibit protein tyrosine kinase, and exert other effects in the human body. Thus, the recent spread of soy consumption in Western populations emphasizes the need to more fully understand the potential effects in the body, especially in abnormal immune conditions. In the present study, the influence of a soy diet on lupus disease in MRL/Mp-lpr/lpr (MRL/lpr) mice was investigated. Weanling female MRL/lpr mice (4 weeks) were fed a soy diet (20% soybean protein and 5% soybean oil). The soy diet exacerbated renal damage; findings in this mouse strain included accelerated proteinuria, elevated serum creatinine concentrations, and reduced creatinine clearance. No effects were detected, however, in C3H/HeN mice, which have the same H-2(k) genetic background as MRL/lpr mice do. A tendency toward an increase in thymus weight and proliferation of T cells in spleen and B cells in lymph nodes were found at the age of 16 weeks. These findings indicate that a soy diet, in comparison with a casein diet, significantly exacerbates the clinical course of this autoimmune disease. Further research on the mechanism of this effect of soy-rich diets is needed, and isoflavone supplementation for systemic lupus erythematosus patients should be carefully reevaluated.

Multi-target models and their application to data analysis of cellular mortality due to radiation exposure.

We consider multi-target models for use in analyzing data of the dose-response relationship. The target sizes we are concerned with here are both homogeneous, as assumed in the classical model, and heterogeneous, as simplified using geometric progression. We apply two models for establishing the multi-target models: a Poisson regression model constructed by assuming that the response variable Y follows Poisson distribution, and a gamma-frailty model as a Poisson mixture model derived by adding random common risks having a gamma distribution. Applying these models to experimental data relating the effects of miso fermentation-stages on the survival rate of cells of intestinal crypts of mice exposed to radiation yielded the result that there were substantial frailties associated with all miso fermentation-stages. Short-term and medium-term fermented miso provided similar effects, whereas long-term fermentation had the lowest-relative risk value, indicating a significant protection of the crypts against exposure effects. A gamma-frailty model based on heterogeneous target size was more suitably applied when there were at least 3 dead stem cells having 10 target genes.

Interferência da infecção por ascaris lumbricoides e giardia lamblia e da toxicidade da farinha de soja inadequadamente processada no aproveitamento da vitamina A e por crianças / Interference of infection by Ascaris lumbricoides and Giardia lamblia and the toxicity of soybean meal improperly processed in the use of vitamin A and children

Objetivou-se com este trabalho, avaliar, de um lado, a interveniência da infecção por A. Zumbricoides e G. Zamblia no aproveitamento de dose maciça de vitamina A administrada a escolares e, de outro, o uso de farinha de soja inadequadamente manipulada como complemento dietetico ã alimentação de crianças de Belo Horizonte. A avaliação da interferência da infecção parasitãria no processo foi realizada comparando-se as modificações ocorridas, nos níveis sericos de retinol, apõs a ingestão de 200 000 UI de vitamina A hidrossoluvel - dose maciça - por escolares de Primeiro Grau dos grupos parasitado e não parasitado. As alterações foram identificadas atraves das determinações do retinol serico realizadas no período anterior à administração da vitamina, confrontadas com os resultados obtidos após 30, 60 e 120 dias da ingestão. O grupo não parasitado era constituído por 25 crianças cujas coproscopias mostraram-se negativas, quando relizadas pelos metodos de Faust (1932) e de Kato modificado (Katz, Chaves e Pellegrino, 1972). O grupo parasitado era camposto por 39 crianças infectadas por A. lumbricoides e ou G. lamblia. A análise dos resultados mostrou que, nas condições em que foram realizadas estas observações, as diferenças encontradas nos níveis medias de retinol, dos grupos parasitado e não parasitado, não foram significativas, indicando que a infecção por A. lumbricoides e G.lamblia não influiram no retinol sérico após tratamento com dose maciça de vitamina A, quando estudado no 300, 600 e 1200 dias...