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In recent years, several indicators have been proposed to assess the effect of human activities on ecosystems provisioning capacity. Some of these methods focus on the Net Primary Production (NPP) available for ecosystem functioning through the comparison between the Human Appropriated Net Primary Production (HANPP) and the ecosystem's initial NPP at a given reference year. While some approaches have been proposed for marine ecosystems, most of the HANPP studies focus on terrestrial systems. This study highlights the relation between the HANPP methods and the production of natural resources in marine ecosystems. The linkage between current overfishing and future fish provisioning (ecosystem service) is well known. However, less studied before, is the relation between seaweed aquaculture and fish provisioning through the marine food web. Seaweed growth requires nutrients and light that will consequently be no longer available for natural phytoplankton production. As seaweed is periodically harvested, a fraction of the ecosystem's NPP (HANPP) is no longer available for ecosystem production. The HANPP of aquaculture reduces the ecosystem carrying capacity and thus affects commercial fish stocks. Therefore, an integrative approach is proposed in this study to assess the potential effect of seaweed farming on fish landings in the Greater North Sea. Three indicators are proposed to assess the Lost Potential Yield (LPY) in fish landings: LPYB, LPYV and LPYE, accounting respectively for reduction in biomass, monetary value and eco-exergy. For these three aspects, the LPY results remains smaller than the seaweed production, meaning that the overall natural resources balance for seaweed farming is positive.

On coral reefs, microorganisms are essential for recycling nutrients to primary producers through the remineralization of benthic-derived organic matter. Diel investigations of reef processes are required to holistically understand the functional roles of microbial players in these ecosystems. Here we report a metagenomic analysis characterizing microbial com- munities in the water column overlying 16 remote forereef sites over a diel cycle. Our results show that microbial community composition is more dissimilar between day and night samples collected from the same site than between day or night samples collected across geographically distant reefs. Diel community differentiation is largely driven by the flux of Psychrobacter sp., which is two-orders of magnitude more abundant during the day. Nighttime communities are enriched with species of Roseobacter, Halomonas, and Alteromonas encoding a greater variety of pathways for carbohydrate catabolism, further illustrating temporal patterns of energetic provisioning between different marine microbes. Dynamic diel fluc- tuations of microbial populations could also support the efficient trophic transfer of energy posited in coral reef food webs. 

Background: Natural polyphenols have potential therapeutic effects on colon-based diseases and gut microbial dysbiosis. However, the delivery of pure polyphenols to the colon has to overcome chemical instability, de- gradation, and metabolism in the upper gastrointestinal tract after oral ingestion. Dietary fibers have been exploited as microbiota-triggered release systems to protect polyphenols in the upper gut and specifically deliver them to the colon. 

Scope and approach: This review focuses on the recent development of colon-targeted polyphenol delivery systems using encapsulation technologies based on dietary fibers for both food and pharmaceutical applications. The detailed characteristics and advantages of commonly used dietary fibers and the main mechanisms of en- capsulation preparation are discussed. The challenges of targeting the colon and the colonic health benefits of polyphenols are elaborated. In addition, the scope for specific modulation of gut microbiota by the selective combination of polyphenol and dietary fiber is highlighted. 

Key findings and conclusions: The microbial-triggered release mechanisms of dietary fiber-based delivery systems maintain the structural integrity and protect the polyphenols during passage through the harsh environment of the upper gastrointestinal tract to maximize their concentration in the colonic region. In addition, dietary fibers offer several advantages over other materials for polyphenol encapsulation and delivery, including strong dietary fiber-polyphenol binding interactions, high colonic mucoadhesion, and synergistic prebiotic effects from dietary fiber and polyphenol that result in health benefits for the colon and the body. 

Brown seaweeds are popular foods in Japan, where the incidence of breast cancer is about 1/6 the rate of that reported for American women. Seaweed is an excellent source of fiber, contains iodine, carotenoids, and both mammalian lignans and isoflavones. Seaweed may help to prevent breast cancer by several different mechanisms involving these and other constituents. In a preliminary study of toxicity and efficacy using 5 g/day of seaweed, we found seaweed was well tolerated and was associated with some biological changes in the variables measured. In this study, we will examine the effects of escalating doses I of seaweed supplementation in a group of healthy postmenopausal women with and without breast cancer. In our cross-over design, women will be randomized to either seaweed or placebo first. We will then give doses of seaweed or placebo (3 g/day for 3 weeks, then 6 g/day for 3 weeks), followed by 1 week of 6 g/day seaweed/placebo plus soy (2 mg isoflavone per kg bodyweight). Our primary outcome variables are changes in circulating estrogen levels, thyroid hormones, and urinary excretion of phytoestrogens. Adherence to our program will be measured by monitoring urinary excretion of iodine.