Bifidobacterium is a well-established probiotic that has been shown to have health benefits by numerous clinical reports and is commonly used as an ingredient in dairy products. In the present study, we investigated the anti-aging effects of Bifidobacterium longum subsp. longum BB536 using Caenorhabditis elegans. The effects of BB536 administration on lifespan, reactive oxygen species (ROS) accumulation, and gene expression were evaluated using wild-type, mutant, and paraquat-induced mitochondrial dysfunction C. elegans models. Compared with wild-type C. elegans administered Escherichia coli OP50, the BB536-administered group showed prolonged lifespans and suppressed ROS accumulation. Additionally, BB536 administration improved age-related declines in physical function and sarcomere structure. Administration of BB536 to the paraquat-induced mitochondrial dysfunction aging model resulted in elevated expression of antioxidant system genes, such as heat shock protein 70 (HSP70), superoxide dismutase 1, thioredoxin-1, and glutathione S-transferase 4. Interestingly, these effects disappeared in the p38 mitogen-activated protein kinase (MAPK)-mutant worms. These results suggest the anti-aging potential of BB536 acts by protecting against ROS stress through the MAPK cascade-signaling pathway, which is evolutionarily preserved throughout eukaryotes, including mammals.
Feeding management of dairy cows significantly influence on milk composition. However, there was little information regarding the effect of feeding management of cows on the taste of milk. The objective of this study was to evaluate whether a taste sensing system was able to discriminate a difference of milk from different farms and under different heat treatments. Forty eight milk samples were prepared by combining raw milk samples from four farms (Farm A, B, C: grazing, Farm D: confinement management), four types of heat treatments including raw milk (raw, UHT, HTST-homogenized, and HTST-non homogenized), and three tests. Milk samples were analyzed using the taste sensing system equipped with 6 probes. The discriminant model could distinguish between milk samples obtained from each farm (R2=0.619 and Q2=0.488, % of correct classification=91.7%). The discriminant model for heat treatments classified heat treatments between HTST and UHT (R2=0.601 and Q2=0.252, % of correct classification=91.7%). However, the discriminant model did not classified between raw milk and HTST milk (R2=0.217 and Q2=0.103), and homogenization (R2=0.221 and Q2=0.058).
Some lactic acid bacteria (LAB) produce diacetyl, which is a major flavor compound in many fermented dairy products. A total of 368 LAB strains of our collection were screened and some high diacetyl producing LAB strains were isolated among 52 citrate utilizing LAB strains. Lactobacillus paracasei #003 strain which accumulated 11.43 μg/mL of diacetyl in cultured 10% (w/v) skim milk medium was selected. Test productions of cream cheese and fermented butter were performed using #003 as an adjunct LAB starter. In the products, diacetyl was accumulated 1.48 and 1.30 μg/g, respectively, and were considerably higher than those of no adjunct starter. Comparative sensory evaluation of those test products and those of no adjunct starter on aroma intension indicated statistically significant differences.
Fermented dairy products have been consumed widely by our society as a part of their daily meal. Nowadays, because of the high awareness of people about health in relation to food consumption, demand on fermented dairy products which are not only affordable, delicious, and fulfil the nutritious requirement, but also beneficial for our health are gaining attention. Traditionally, there are many fermented milk products produced in some area in the world and have been believed to confer beneficial effect to host. However, because the fermentation processes occur naturally, the quality of the products is not always stable. Several studies have been done to isolate and characterize the indigenous starter microorganisms from several traditional dairy products, for example some endogenous lactic acid bacteria from traditional fermented milk or moulds from fermented cheeses. To exhibit functional effect, starter microorganisms should be well proven to show good physiological effects, not only during fermentation but also when they enter host's body. In this review, biochemical studies on probiotic properties of endogenous Lactobacillus rhamnosus strains isolated from fermented Sumbawa mare's milk (FSMM) and also characterization of several non-commercial Penicillium strains as mould-ripened cheeses starter will be discussed.