V. Rama Mohan Gupta

Alike many allopathic lipophilic drug molecules, these natural phyto-constituents are potent, lipophilic, but pose problems like poor aqueous solubility, slower drug release profile, and, reduced bioavailability leading to inferior therapeutic efficacy. This creates scope as well as a challenge for researchers to overcome the above-mentioned problems while developing a formulation for poorly aqueous soluble phytoconstituents. Herbosome is one of the efficient techniques to improve these problems. Herbosome /Phytosome is nothing but the combination of liposome with phytoconstituents forming H-bond anchored amphiphilic drug-phospholipids complexes. Quercetin i.e. 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-1-benzopyran-4-one is a polyphenolic flavonoid with potent and diverse biological effects like anti-inflammatory, anti-proliferative, and anti-mutagenic. However, like many other potent drugs, its usage is limited due to its poor aqueous solubility. To overcome this problem, an ameliorated complex of phospholipids loaded with quercetin was developed to improve its aqueous solubility for better absorption. Thus quercetin encapsulated in herbosomes/phytosomes was assessed for the phospholipid complex formation, appearance, surface, and porosity evaluation using different physicochemical tests like FT­IR, DSC, XRPD, 1H-NMR, SEM, and solubility studies. Apart from this anti-oxidant activity of quercetin was evaluated in vitro. The surface characteristics of herbosomes appeared to be flocculent and permeable with a coarse surface in SEM studies whereas FTIR, DSC, 1H-NMR, and XRPD data, confirmed the formation of the phospholipids complex. There were 12 folds improvement in aqueous solubility of per se quercetin and quercetin encapsulated in herbosome (i.e. from 3.44 µg/ml to 36.81 µg/ ml). On the other hand, the results of in vitro anti­oxidant activity of phytosomic quercetin showed no significant statistical difference compared to per se quercetin thus indicating no adverse effects of complexation on quercetin’s availability for anti­oxidant activity. Further, we prepared tard-gelatin capsules containing phytosomic quercetin and evaluated them for drug release, drug content, and solubility studies like dissolution, disintegration, drug content, and stability studies. The results for the evaluation of the kinetics of drug release were in line with the Korsmeyer Peppas model. The drug stability studies did not affect the drug's organoleptic properties, disintegration time, drug content, and in-vitro drug release of the formulation.

Black pepper, also designated as ‘King of spices’ a characteristic familiar global spice related to the Piperaceae family and generally used in culinary and medicinal preparations. Its pungency is due to piperine, volatile elements and essential oil. Piperine is an amide alkaloid, effective bioactive present in piper species of black and long peppers; and reveals several potential therapeutic actions to intervene different disease conditions whereas functional group responses at active site liable to act as a xenobiotic bio-enhancer and an effective CNS stimulant. However, piperine is slightly soluble in water, limiting its pharmacological activities and biomedical services. It is solid crystalline nature, mild basic, initially tasteless while, a burning after taste. Therefore, this bioactive natural substance should be considered in the arenas of rational drug design and development of formulations. Recent developments in drug delivery system have to overcome its limitations, including poor bioavailability and blood–brain barrier permeability.  Chaperons like phytosomes are encouraging tools to alter oral absorption of piperine. The study highlights the prepared and correctly recognized piperine-phospholipid complex (PPC) in terms of FT-IR (Fourier Transform Infra-red spectroscopy), DSC (differential scanning calorimetry), XRPD (X-ray powder diffractometry), and SEM (scanning electron microscopy). The PPC was found to be fine and loose, airy, light, rough surface with improved water solubility and bioavailability.

Solubility is an important physicochemical factor affecting absorption of drug and its therapeutic effectiveness. Drugs having poor aqueous solubility present one of the major confronts better absorption for good bioavailability of such drugs. The purpose of this study was to prepare and characterize solid dispersions of the poorly water soluble antihypertensive agent valsartan with water soluble carriers such as Kolliphor P 407, Kolliphor P 188, Kolliwax GMS II, Kolliphor HS15, HPMC AS and Soluplus in proportions viz. 1:1, 1:3, 1:5 (Drug: Carrier) with addition of 2% SLS to improve its aqueous solubility and rate of dissolution by solvent evaporation technique. All the formulations showed marked improvement in the solubility behavior and improved drug release. From all the formulations  SD6 was found to be optimized formulation  using soluplus as carrier based on the solubility and dissolution studies. The results obtained showed that the aqueous solubility and rate of dissolution was significantly improved when formulated in solid dispersion as compare to pure drug.