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Abstract: Conjugated linoleic acid (CLA) consists of a group of geometric and positional isomers of linoleic acid to which anticancerogenic, antidiabetic, and antiatherogenic effects, as well as effects on immune system, bone metabolism, and body composition are attributed. CLA is found predominantly in milk and meat of ruminants due to the importance of rumen micro-organism in the formation of CLA and its precursors. This review attempts to give an overview of the available data on intramuscular CLA concentrations in meat and meat products originating from different animal species. The factors influencing these concentrations are discussed and the estimated human daily intakes as well as the percentage provided by meat are reported. [Copyright &y& Elsevier]

The conjugated linoleic acid (CLA) isomers present in milk fat have a high health amelioration potential. Their high prevalence in fat of ruminants and in milk and dairy products has been described and confirmed over many years. The CLA isomers are formed during biohydrogenation of linoleic acid in the rumen and also through conversion of vaccenic acid in the mammary gland. In addition, several strains of Lactobacillus, Propionibacterium, Bifidobacterium and Enterococcus are able to form CLA from linoleic acid and thus could be used to increase the CLA level in fermented dairy products such as yoghurt and cheese. It appears likely that lactic acid bacteria and especially propionibacteria can form CLA during cheese ripening because free linoleic acid is formed in the ripening process. However, for the time being the reviewed data allow no final conclusion on whether these increased levels of CLA are mainly due to formation by microorganisms, or due to cattle feed or breed. Further studies including all these parameters will be necessary to elucidate the potential role of starter cultures to achieve physiologically relevant CLA levels in dairy products. It appears that contribution of presently used dairy starter bacteria to increased CLA content in cheese is relatively minor. [Copyright &y& Elsevier]

Two new terpyridine dimanganese oxo complexes [Mn2[supIII,IV](7-O)2(terpy)2(CF3CO2)2][sup+] (3) and [Mn2[supIII,III](7-O)(terpy)2(CF3CO2)4] (4) (terpy = 2,2`:6,2`u`-terpyridine) have been synthesized and their X-ray structures determined. In contrast to the corresponding mixed-valent aqua complex [Mn2[supIII,IV](7-O)2(terpy)2(H2O)2][sup3+] (1), the two Mn atoms in 3 are not crystallographically equivalent. The neutral binuclear monooxo manganese(III,III) complex 4 exhibits two crystallographic forms having cis and trans configurations. In the cis complex, the two CF3CO2[sip-] ligands on each manganese adopt a cis geometry to each other; one CF3CO2[sup-] is trans to the oxygen of the oxo bridge while the second is cis. In the trans complex, the two coordinated CF3CO2[sup-] have a trans geometry to each other and are cis to the oxo bridge. The electrochemical behavior of 3 in organic medium (CH3CN) shows that this complex could be oxidized into its corresponding stable manganese(IV,IV) species while its reduced form manganese(III,III) is very unstable and leads by a disproportionation process to Mn(II) and Mn(IV) complexes. Complex 4 is only stable in the solid state, and it disproportionates spontaneously in CH3CN solution into the mixed-valent complex 3 and the mononuclear complex [Mn[supII](terpy)2][sup2+] (2), thereby preventing the observation of its electrochemical behavior.