Piperine

The present manuscript describe simple, sensitive, rapid, accurate, precise and cost effective dual wavelength spectrophotometric method for the simultaneous determination of Rifampicin and Piperine in combined capsule dosage form. The utility of dual wavelength data processing program is its ability to calculate unknown concentration of components of interest in a mixture containing an interfering component. The principle for dual wavelength method is “the absorbance difference between two points on the mixture spectra is directly proportional to the concentration of the component of interest”. The method was based on determination of Rifampicin at the absorbance difference between 286 nm and 357 nm and Piperine at the absorbance difference between 356 nm and 479 nm. The linearity was obtained in the concentration range of 10-60 μg/ml for Rifampicin and 1-10 μg/ml for Piperine. The mean recovery was 98.40 ± 0.48 and 98.59 ± 0.46 for Rifampicin and Piperine, respectively. The method was successfully applied to pharmaceutical dosage form because no interference from the capsule excipients was found. The suitability of these methods for the quantitative determination of Rifampicin and Piperine was proved by validation. The proposed methods were found to be simple and sensitive for the routine quality control application of Rifampicin and Piperine in pharmaceutical capsule dosage form. The results of analysis have been validated statistically and by recovery studies.

Piperine (1-peperoyl piperidine), a pungent alkaloid, is found in various Pipper species. Piperine produces antioxidant, antiplatelet, anti-inflammatory, antihypertensive, hepatoprotective, antithyroid, antitumor, antiasthmatic activities and also a fertility enhancer. Piperine enhances absorption from gastrointestinal tract by various mechanisms and reduces gut metabolism of drugs. Piperine modulates membrane dynamics and lipid environment and increases permeability at site of absorption Molecular structure of piperine is suitable for enzyme inhibition and it inhibits various metabolizing enzymes like cytochrome bs, NADPH cytochrome, CYP3A4, UDP-glucose dehydrogenase (UDP-GDH), aryl hydrocarbon hydroxylase (AAH) and UDP-glucuronyl transferase. Structural modification of piperine provides selective inhibitors of various cytochrome p450 enzymes. Inhibition of these enzymes by piperine results in enhanced bioavailability of drugs and nutrients like oxytetracyclin, metronidazole, ampicillin, norfloxacin, ciprofloxacin, acefotaxime, amoxicillin trihydrate, curcumin, beta-carotene, carbamazepine, gallic acid, nimesulide, tiferron, nevirapine, pentobarbitone, phenytoin, resveratrol, vasicine and sparteine by different mechanisms. Thus piperine is an absorption enhancer and a potent inhibitor of drug metabolism. Key words: Piperine, Metabolism inhibitor, Absorption enhancer, Bio-enhancer, bioavailability