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Biotech / Medical : Biotech Valuation -- Ignore unavailable to you. Want to Upgrade?

To: OldAIMGuy who wrote (23291)	3/22/2007 12:49:50 PM
From: Biomaven	Read Replies (1) \| Respond to of 52153

White pepper also contains piperine, but I after a bit of googling I can't find the relative piperine content of white and black pepper. Black pepper contains about 5-9% piperine-like alkaloids, but I don't see the corresponding number for white pepper. This link however indicates that white pepper definitely does contain piperine at some level: kalsec.com In general piperine is going to increase the intestinal absorption of some compounds. Whether that makes food more digestible or less digestible I guess depends on your definition of "digestible." :) It does increase absorption of some drugs, notably phenytoin and some antibiotics. Here is one possible explanation of the mechanics: Phytomedicine. 2002 Apr;9(3):224-31. Links Piperine modulates permeability characteristics of intestine by inducing alterations in membrane dynamics: influence on brush border membrane fluidity, ultrastructure and enzyme kinetics. * Khajuria A, * Thusu N, * Zutshi U. Manitoba Institute of Cell Biology, Winnipeg, Canada. akhajuria@hsc.mb.ca Piperine (1-Piperoyl piperidine) is a major alkaloid of Piper nigrum Linn. and Piper longum Linn. It is shown to possess bioavailability-enhancing activity with various structurally and therapeutically diverse drugs. The mechanism of enhancing the bioavailability, is, however, not understood. We hypothesize that piperine's bioavailability-enhancing property may be attributed to increased absorption, which may be due to alteration in membrane lipid dynamics and change in the conformation of enzymes in the intestine. Results of membrane fluidity studies using an apolar fluorescent probe, pyrene (which measures the fluid properties of hydrocarbon core), showed an increase in intestinal brush border membrane (BBM) fluidity. Piperine also stimulated Leucine amino peptidase and Glycyl-glycine dipeptidase activity, due to the alteration in enzyme kinetics. This suggests that piperine could modulate the membrane dynamics due to its apolar nature by interacting with surrounding lipids and hydrophobic portions in the protein vicinity, which may decrease the tendency of membrane lipids to act as stearic constrains to enzyme proteins and thus modify enzyme conformation. Ultra structural studies with piperine showed an increase in microvilli length with a prominent increase in free ribosomes and ribosomes on the endoplasmic reticulum in enterocytes, suggesting that synthesis or turnover of cytoskeletal components or membrane proteins may be involved in the observed effect. In conclusion, it is suggested that piperine may be inducing alterations in membrane dynamics and permeation characteristics, along with induction in the synthesis of proteins associated with cytoskeletal function, resulting in an increase in the small intestine absorptive surface, thus assisting efficient permeation through the epithelial barrier. Peter