Synergistic chains

Synergistic chain Eliminates duplication by leveraging buying power Common in large, multiple division companies Focus on commodity purchases No competitive advantage 2... 

Synergistic chain Operations centric, focusing on sourcing, an enable process... 

There has been some evidence of a higher antioxidant effect when both flavonoids and a-tocopherol are present in systems like LDL, low-density lipoproteins (Jia et al., 1998 Zhu et al, 1999). LDL will incorporate a-tocopherol, while flavonoids will be present on the outside in the aqueous surroundings. A similar distribution is to be expected for oil-in-water emulsion type foods. In the aqueous environment, the rate of the inhibition reaction for the flavonoid is low due to hydrogen bonding and the flavonoid will not behave as a chain-breaking antioxidant. Likewise, in beer, none of the polyphenols present in barley showed any protective effect on radical processes involved in beer staling, which is an oxidative process (Andersen et al, 2000). The polyphenols have, however, been found to act synergistically... 

Fig. 16.5 Synergistic regeneration of a-tocopherol by quercetin at a lipid-water interphase. a-tocopherol is reacting with a lipid peroxyl radical in a chain-breaking reaction. According to the standard reduction potential, the phenoxyl radical of quercetin can further be regenerated by ascorbate.

Sato, K., Niki, E. and Shimasaki, H. (1990). Free radical mediated chain oxidation of LDL and its synergistic inhibition by vitamin E and vitamin C. Arch. Biochem. Biophys. 279, 402-405. 

Vitetta, E.S., and Thorpe, P.E. (1985) Immunotoxins containing ricin A or B chains with modified carbohydrate residues act synergistically in killing neoplastic B cells in vitro. Cancer Drug Deliv. 2, 191. 

Baraldi M, Pinelli G, Ricci P, Zeneroli ML Toxins in hepatic encephalopathy The role of the synergistic effect of ammonia, mercaptans and short chain fatty acids. Arch Toxicol 1984 7 103-105. 

The rare example of synergistic action of a binary mixture of 1-naphthyl-A-phcnylaminc and phenol (1-naphthol, 2-(l,l-dimethylethyl)hydroquinone) on the initiated oxidation of cholesterol esters was evidenced by Vardanyan [34]. The mixture of two antioxidants was proved to terminate more chains than both inhibitors can do separately ( > /[xj). For example, 1-naphtol in a concentration of 5 x 10 5 mol L-1 creates the induction period t=170s, 1 -naphthyl-A-phenylamine in a concentration of 1.0 x 10-4 mol L 1 creates the induction period t = 400s, and together both antioxidants create the induction period r = 770 s (oxidation of ester of pelargonic acid cholesterol at 7= 348 K with AIBN as initiator). Hence, the ratio fs/ZfjXi was found equal to 2.78. The formation of an efficient intermediate inhibitor as a result of interaction of intermediate free radicals formed from phenol and amine was postulated. This inhibitor was proved to be produced by the interaction of oxidation products of phenol and amine. 

The combined addition of two phenols, one of which is sterically hindered, for example, 2,6-bis(l,l-dimethylethyl)phenol, and another is sterically nonhindered also leads to a synergistic effect [35-38]. As found by Mahoney [35], 2,4,6-tris(l,l-dimethylethyl)phenol with a concentration of 10 4 L mol 1 does not virtually inhibit the initiated oxidation of 9,10-dihydroan-thracene (333 K), but /)-methoxyphenol, taken in the same concentration, does inhibit oxidation. The induction period doubles if two phenols are added together in equal concentrations, which indicates that both phenols are involved in chain termination. The mechanism of synergistic action can be explained by the following kinetic scheme [35] ... 

It is seen that the substitution of the part of amine or phenol by quinone prolongs the induction period by two or three times. The mechanism of synergistic action of quinone is the same as in the case of nitroxyl radicals. Quinone reacts with InH with production of semiquinone radicals. The latter rapidly reacts with peroxyl radicals and provokes the additional rapid chain termination [47],... 

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