Xanthohumol and related prenylflavonoids from hops and beer: to your good health!

Xanthohumol (3'-[3,3-dimethyl allyl]-2',4',4-trihydroxy-6'-methoxychalcone) is the principal prenylated flavonoid of the female inflorescences of the hop plant ('hops'), an ingredient of beer. Human exposure to xanthohumol and related prenylflavonoids, such as 8-prenylnaringenin and isoxanthohumol, is primarily through beer consumption. Xanthohumol has been characterized a 'broad-spectrum' cancer chemopreventive agent in in vitro studies, while 8-prenylnaringenin enjoys fame as the most potent phytoestrogen known to date. These biological activities suggest that prenylflavonoids from hops have potential for application in cancer prevention programs and in prevention or treatment of (post-)menopausal 'hot flashes' and osteoporosis. Xanthohumol and 8-prenylnaringenin are metabolized into many flavonoid derivatives with modified 3,3-dimethyl allyl (prenyl) moieties. Xanthohumol is formed in lupulin glands by a specialized branch of flavonoid biosynthesis that involves prenylation and O-methylation of the polyketide intermediate chalconaringenin. Although a lupulin gland-specific chalcone synthase is known, the aromatic prenyltransferase and O-methyltransferase participating in xanthohumol have not been identified. The prenylflavonoid pathway is a possible target for breeding or biotechnological modification of hops with the aim of increasing xanthohumol levels for beer brewing and 8-prenylnaringenin levels for pharmaceutical production.     

On Cognitive and Moral Enhancement: A Reply to Savulescu and Persson

In a series of recent works, Julian Savulescu and Ingmar Persson insist that, given the ease by which irreversible destruction is achievable by a morally wicked minority, (i) strictly cognitive bio‐enhancement is currently too risky, while (ii) moral bio‐enhancement is plausibly morally mandatory (and urgently so). This article aims to show that the proposal Savulescu and Persson advance relies on several problematic assumptions about the separability of cognitive and moral enhancement as distinct aims. Specifically, we propose that the underpinnings of Savulescu's and Persson's normative argument unravel once it is suitably clear how aiming to cognitively enhance an individual will in part require that one aim to bring about certain moral goods we show to be essential to cognitive flourishing; conversely, aiming to bring about moral enhancement in an individual must involve aiming to improve certain cognitive capacities we show to be essential to moral flourishing. After developing these points in some detail, and their implication for Savulescu's & Persson's proposal, we conclude by outlining some positive suggestions.     

Anthropology Is Dead! Long Live Anthropology!

Cultural Studies . Lawrence Grossberg, Cary Nelson , and Paula A. Treichler , eds. New York: Routledge, 1992. 798 pp.     

Entertainment!

Abstract

Robertson Davies, The Lyre of Orpheus. New York: Viking Penguin, 1988. 472 pages. $19.95 hardback.