Hydrophobic Hydrophobicity

Both the 3i4- and 2.5i2-helical backbones have been found suitable for the design of antimicrobial /9-peptides. In order to cluster polar residues on one face of the helix, amphiphilic 3i4-helical /9-peptides have been constructed from hydro-phobic-cationic-hydrophobic or hydrophobic-hydrophobic-cationic residue triads... 

The pepsin, activated by cleavage of a proenzyme, has two putative active site domains comprising hydrophobic-hydrophobic-Asp-Thr-Gly amino acids, is potentially glycosylated and has a free cysteine residue which may allow it to form dimers, as in the case of human and Plasmodium falciparum-derived aspartyl proteases (Longbottom et al., 1997). However,... 

Topical spermicides such as nonoxynol-9 (N9) and benzalkonium chloride act on sperm membranes through a detergent effect, namely, hydrophobe-hydrophobe interaction between the active and substrate (spermatozoa). The idea was to optimize the cationic/hydrophobic polymer in the drug delivery system so epithelial cells were protected without sacrificing the drug s spermicidal activity. One of the questions that needed to be answered in designing an optimum cationic/hydrophobe modified polymer was the effect of the hydrophobe on the drug activity (N9 initially, and other actives subsequently). 

Amyloid-like AntiparaUel yS-sheet" Alternating hydrophilic/ hydrophobic Hydrophobic nucleation followed by hydrogen bond propagation Parallel... 

Weber et al. reported that high-end costs for slurry-phase biological treatment were just under 200/yd of soil treated. This value represented the lowest of the high-end values reported. Weber et al. noted that these high-end values are more realistic representations of hPAHs treatment costs since these compounds are highly hydrophobic. Hydrophobic compounds have slower treatment rates and thus require longer treatment times. This factor adds to remediation costs (D194723, pp. 79, 80). 

Hydrophobic Hydrophobic Gradient Adsorption at high salt... 

Hydrophobicity Hydrophobicity is the association of non polar groups or molecules in an aqueous environment which arises from the tendency of water to exclude non polar molecules (IUPAC). See Lipophilicity. 

Hydroxide A/HEC molar ratio Hydrophobe Hydrophobe MS Alkylation efficiency 1% Brookfield viscosity... 

In addition, medium effects play an important role through the interaction of solvent molecules with p and a as well as with each other thus the two partners should present geometrically matched hydrophobic/hydrophobic or hydrophilic/hydro-philic (solvophobic, solvophilic, more generally) domains. 

Fig. 4.2 Dimensions and hydrophobic/hydrophobic regions of the CD molecules. (From ref. [13])...

If apolar hydration is characterized by the conditions that AG° > 0, TAS < 0 and AH < 0, then a process which minimizes exposure of apolar groups to water should be a thermodynamically favoured process. Then if two apolar groups of either the same or different molecules come together in water, AS for this process will be positive because some of the structured water is released into the bulk solvent. Such association is called hydrophobic, hydrophobic bonding or hydrophobic interaction (Kauzmann, 1959). The term bond is probably inappropriate because the association is due to entropy rather than to enthalpy effects, a consequence of the disruption of the clathrate structure around the apolar solute (Jolicoeur and Friedman, 1974). Despite the general acceptance of the concept of hydrophobic association, there are different approaches to the problem of understanding this phenomenon. 

Presence of hydrophobic Hydrophobic interaction Association with hydrophobic regions... 

Another AFM-based technique is chemical force microscopy (CFM) (Friedsam et al. 2004 Noy et al. 2003 Ortiz and Hadziioaimou 1999), where the AFM tip is functionalized with specific chemicals of interest, such as proteins or other food biopolymers, and can be used to probe the intermolecular interactions between food components. CFM combines chemical discrimination with the high spatial resolution of AFM by exploiting the forces between chemically derivatized AFM tips and the surface. The key interactions involved in food components include fundamental interactions such as van der Waals force, hydrogen bonding, electrostatic force, and elastic force arising from conformation entropy, and so on. (Dther interactions such as chemical bonding, depletion potential, capillary force, hydration force, hydrophobic/ hydrophobic force and osmotic pressure will also participate to affect the physical properties and phase behaviors of multicomponent food systems. Direct measurements of these inter- and intramolecular forces are of great interest because such forces dominate the behavior of different food systems. 

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