Bruce German

Dr. Bruce German

1. Department of Food Science and Technology, University of California, Davis, Davis, CA, USA
+1

Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 April 2015 in Microbiome
Verified
Journal Article
Open access
PDF file
ZLZachery T Lewis
Zachery T Lewis
STSarah M Totten
Sarah M Totten
Jennifer SmilowitzJennifer Smilowitz
Jennifer Smilowitz
MPMina Popovic
Mina Popovic
EPEvan Parker
Evan Parker
DMDavid A Mills
David A Mills
Individuals with inactive alleles of the fucosyltransferase 2 gene (FUT2; termed the ‘secretor’ gene) are common in many populations. Some members of the genus Bifidobacterium, common infant gut commensals, are known to consume 2′-fucosylated glycans found in the breast milk of secretor mothers. We investigated the effects of maternal secretor status on the developing infant microbiota with a special emphasis on bifidobacterial species abundance. On average, bifidobacteria were established earlier and more often in infants fed by secretor mothers than in infants fed by non-secretor mothers. In secretor-fed infants, the relative abundance of the Bifidobacterium longum group was most strongly correlated with high percentages of the order Bifidobacteriales. Conversely, in non-secretor-fed infants, Bifidobacterium breve was positively correlated with Bifidobacteriales, while the B. longum group was negatively correlated. A higher percentage of bifidobacteria isolated from secretor-fed infants consumed 2′-fucosyllactose. Infant feces with high levels of bifidobacteria had lower milk oligosaccharide levels in the feces and higher amounts of lactate. Furthermore, feces containing different bifidobacterial species possessed differing amounts of oligosaccharides, suggesting differential consumption in situ. Infants fed by non-secretor mothers are delayed in the establishment of a bifidobacteria-laden microbiota. This delay may be due to difficulties in the infant acquiring a species of bifidobacteria able to consume the specific milk oligosaccharides delivered by the mother. This work provides mechanistic insight into how milk glycans enrich specific beneficial bacterial populations in infants and reveals clues for enhancing enrichment of bifidobacterial populations in at risk populations - such as premature infants.

17 July 2014 in Annual Review of Nutrition
Verified
Journal Article
Closed access
Jennifer SmilowitzJennifer Smilowitz
Jennifer Smilowitz
CLCarlito Lebrilla
Carlito Lebrilla
DMDavid A Mills
David A Mills
BGBruce German
Bruce German
SFSamara L. Freeman
Samara L. Freeman
In addition to providing complete postnatal nutrition, breast milk is a complex biofluid that delivers bioactive components for the growth and development of the intestinal and immune systems. Lactation is a unique opportunity to understand the role of diet in shaping the intestinal environment including the infant microbiome. Of considerable interest is the diversity and abundance of milk glycans that are energetically costly for the mammary gland to produce yet indigestible by infants. Milk glycans comprise free oligosaccharides, glycoproteins, glycopeptides, and glycolipids. Emerging technological advances are enabling more comprehensive, sensitive, and rapid analyses of these different classes of milk glycans. Understanding the impact of inter- and intraindividual glycan diversity on function is an important step toward interventions aimed at improving health and preventing disease. This review discusses the state of technology for glycan analysis and how specific structure-function knowledge is enhancing our understanding of early nutrition in the neonate.

1 October 2007 in Journal of Agricultural and Food Chemistry
Verified
Journal Article
Closed access
RLRiccardo G. LoCascio
Riccardo G. LoCascio
MNMilady R. Ninonuevo
Milady R. Ninonuevo
SFSamara L. Freeman
Samara L. Freeman
DSDavid A. Sela
David A. Sela
RGRudolf Grimm
Rudolf Grimm
BGBruce German
Bruce German

1 July 2000 in Annual Review of Nutrition
Verified
Journal Article
Closed access
BGBruce German
Bruce German
RWRosemary L. Walzem
Rosemary L. Walzem
▪ Abstract Epidemiologic studies from numerous disparate populations reveal that individuals with the habit of daily moderate wine consumption enjoy significant reductions in all-cause and particularly cardiovascular mortality when compared with individuals who abstain or who drink alcohol to excess. Researchers are working to explain this observation in molecular and nutritional terms. Moderate ethanol intake from any type of beverage improves lipoprotein metabolism and lowers cardiovascular mortality risk. The question now is whether wine, particularly red wine with its abundant content of phenolic acids and polyphenols, confers additional health benefits. Discovering the nutritional properties of wine is a challenging task, which requires that the biological actions and bioavailability of the >200 individual phenolic compounds be documented and interpreted within the societal factors that stratify wine consumption and the myriad effects of alcohol alone. Further challenge arises because the health benefits of wine address the prevention of slowly developing diseases for which validated biomarkers are rare. Thus, although the benefits of the polyphenols from fruits and vegetables are increasingly accepted, consensus on wine is developing more slowly. Scientific research has demonstrated that the molecules present in grapes and in wine alter cellular metabolism and signaling, which is consistent mechanistically with reducing arterial disease. Future research must address specific mechanisms both of alcohol and of polyphenolic action and develop biomarkers of their role in disease prevention in individuals.

1 June 2006 in Applied and Environmental Microbiology
Verified
Journal Article
Open access
PDF file
RWRobert Ward
Robert Ward
MNMilady Niñonuevo
Milady Niñonuevo
DMDavid A. Mills
David A. Mills
CLCarlito B. Lebrilla
Carlito B. Lebrilla
BGBruce German
Bruce German
It has been proposed that human milk oligosaccharides (HMO) function as a prebiotic for bifidobacteria, yet this activity has not been adequately investigated. In this study, Bifidobacterium infantis was shown to ferment purified HMO as a sole carbon source, while another gut commensal, Lactobacillus gasseri , did not ferment HMO. Our results support the hypothesis that HMO selectively amplify bacterial populations in the infant intestine.

1 January 2006 in Critical Reviews in Food Science and Nutrition
Verified
Journal Article
Closed access
BGBruce German
Bruce German
CDCora J. Dillard
Cora J. Dillard
Milkfat is a remarkable source of energy, fat-soluble nutrients and bioactive lipids for mammals. The composition and content of lipids in milkfat vary widely among mammalian species. Milkfat is not only a source of bioactive lipid components, it also serves as an important delivery medium for nutrients, including the fat-soluble vitamins. Bioactive lipids in milk include triacylglycerides, diacylglycerides, saturated and polyunsaturated fatty acids, and phospholipids. Beneficial activities of milk lipids include anticancer, antimicrobial, anti-inflammatory, and immunosuppression properties. The major mammalian milk that is consumed by humans as a food commodity is that from bovine whose milkfat composition is distinct due to their diet and the presence of a rumen. As a result of these factors bovine milkfat is lower in polyunsaturated fatty acids and higher in saturated fatty acids than human milk, and the consequences of these differences are still being researched. The physical properties of bovine milkfat that result from its composition including its plasticity, make it a highly desirable commodity (butter) and food ingredient. Among the 12 major milk fatty acids, only three (lauric, myristic, and palmitic) have been associated with raising total cholesterol levels in plasma, but their individual effects are variable—both towards raising low-density lipoproteins and raising the level of beneficial high-density lipoproteins. The cholesterol-modifying response of individuals to consuming saturated fats is also variable, and therefore the composition, functions and biological properties of milkfat will need to be re-evaluated as the food marketplace moves increasingly towards more personalized diets.