NOVELTY - Biomass comprises at least one isolated methylotrophic bacterial culture, where the bacteria are genetically modified or artificially preselected to produce elevated levels of a carotenoid compound relative to the corresponding unmodified or unselected bacterium.    USE - The biomass is useful in a feed composition which is used for consumption by fish of species farmed for human consumption that has pink-, reddish-, yellow-, or orange-colored flesh and producing a fish or seafood product (claimed) or as animal feed, or human nutritional supplements in foods including beverages, juices, and liquors, jellies and biscuits, dairy products, rice and soft rice or porridge, or infant formulas for treating inflammatory diseases, asthma, atopic dermatitis, allergies, multiple myeloma, arteriosclerosis, cardiovascular disease, liver disease, cerebrovascular disease, thrombosis, neoangiogenesis-related diseases including cancer, rheumatism, diabetic retinopathy, macular degeneration, brain disorder, hyperlipidemia, kidney ischemia, diabetes, hypertension, tumor proliferation and metastasis, metabolic disorders, fatigue, and other life habit-related diseases. No biological data given.    ADVANTAGE - The biomass provides food products which: exhibit an elevated level of carotenoid pigment in the flesh (claimed); and does not contain, or contains less of, artificially introduced antibiotics or antiinflammatory compounds.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) a feed composition, comprising the biomass; (2) preparing the biomass, comprising culturing in an appropriate medium methylotrophic bacteria, and collecting the biomass; (3) an Methylobacterium extorquens comprising a non-lethal knock-out of shc; (4) producing fish or seafood, comprising farming fish or seafood, and providing the feed composition to the fish or seafood; and (5) a fish or seafood product exhibiting an elevated level of a carotenoid pigment in the flesh, where the level is attributable to the diet comprising the feed.