Phytochemical Studies on Two Unexplored Endemic Medicinal Plants of India, Barleria terminalis and Calacanthus grandiflorus

Barleria terminalis Nees and Calacanthus grandiflorus (Dalzell) Radlk. are endemic medicinal plants of the Western Ghats of India. The aim of the present research work was to investigate phytochemical profile, potent bioactives using RP-HPLC, LC-MS and GC-MS and to evaluate their bioactivities. Acetone was found to be the best extraction medium for separating phytochemicals. Similarly, acetone and methanol extracts exhibited potential antioxidant properties. Ethanol extract of B. terminalis stem showed potent acetylcholinesterase (AChE) (89.10 ± 0.26%) inhibitory activity. Inhibition of α-amylase (36.96 ± 2.96%) activity was observed the best in ethanol extract of B. terminalis leaves and α-glucosidase inhibitory activity (94.33 ± 0.73%) in ethanol extract of C. grandiflorus stem. RP-HPLC analysis confirmed the presence of several phenolic compounds (gallic acid, hydroxybenzoic acid, vanillic acid, chlorogenic acid and coumaric acid) and phenylethanoid glycoside (verbascoside). The highest phenolics content were observed in B. terminalis (GA (4.17 ± 0.002), HBA (3.88 ± 0.001), VA (4.54 ± 0.001), CHLA (0.55 ± 0.004) mg/g DW, respectively). Similarly, LC-MS and GC-MS revealed the presence of phenolics, glycosides, terpenes, steroids, fatty acids, etc. Moreover, positive correlation between studied phytochemicals and antioxidants was observed in principal component analysis. Based on the present investigation, we conclude that B. terminalis and C. grandiflorus can be further explored for their active principles particularly, phenylethanoid glycosides and iridoids and their use in drug industry for pharmaceutical purposes.

Simultaneous Rp-Hplc Method For Determination Of Betamethasone Dipropionate And Tolnaftate In Combined Semisolid Formulation

A new RP-HPLC method was developed for selective and simultaneous determination of betamethasone dipropionate and tolnaftate in combined semisolid formulation containing other components. Further, the proposed method was validated for linearity, precision (system precision, method precision, intermediate or inter-day precision), accuracy, stability in analytical solution, robustness or system suitability and ruggedness. The developed method exhibited the best results in terms of the aforesaid validation parameters. The other components and additives did not interfere in their determinations. The method was found to be selective, simple, economical, accurate, reproducible, rapid and reliable for routine estimation purpose of these drugs in combined semisolid formulations.

SIMULTANEOUS ESTIMATION OF AZILSARTAN AND CILNIDIPINE IN BULK BY RP-HPLC AND ASSESSMENT OF ITS APPLICABILITY IN MARKETED TABLET DOSAGE FORM

Objective: This study aims to build up the RP-HPLC process for Azilsartan and Cilnidipine and authenticate the RP-HPLC process according to ICH validation code Q2R1. Methods: System suitability testing was performed to discover the qualifying criterion of the method by injecting the identical standard solution of Azilsartan 40μg/ml and Cilnidipine 10μg/ml in mixture/combination in subsequent optimized chromatographic conditions and the chromatogram was recorded. Moreover, the planned method was validated as per ICH guideline Q2R1 for the following parameters: linearity and range, precision, accuracy, robustness, and determined % recovery. Results: The outcomes of %RSD for retention time and peak area were found to be 0.65 and 1.32 for Azilsartan and 0.85 and 1.90 for Cilnidipine. The correlation coefficient, y-intercept, slope of the regression line were 0.9996,-1127.1, 3313.9, and 0.9993, 1460.2, 2876.4 for Azilsartan and Cilnidipine, respectively. Moreover, the range of this method was observed to be 40-240μg/ml and 10-60 μg/ml for Azilsartan and Cilnidipine, standard concentrations respectively. The % RSD achieved for precision (repeatability) was observed in the range of 1.57 to 2.43 for Azilsartan and 0.70 to 1.88 for Cilnidipine. The % accuracy was found in the range of 96.96 to 101.92% w/w for Azilsartan and 99.19 to101.96%w/w for Cilnidipine. The percent recovery values achieved for Azilsartan were in the range of 99.87 to 106.39% w/w and for Cilnidipine in the range of 94.51 to 105.96% w/w. Conclusion: The author concludes that the simultaneous estimation of Azilsartan and Cilnidipine with predefined objectives was successfully achieved. Moreover, the method was found to be steadfast for the quantification of Azilsartan and Cilnidipine in marketed tablet dosage forms.

SIMULTANEOUS DETERMINATION OF TIGECYCLINE AND ITS POTENTIAL IMPURITIES BY A STABILITY-INDICATING RP-HPLC-UV DETECTION TECHNIQUE

Objective: Stability representing the RP-HPLC method was established for synchronized quantification of Tigecycline and its impurities. This method was confirmed for its applicability to both tablet dosage and bulk drug forms. Methods: Intended for an isocratic elution, a mobile phase containing methanol: 10 mmol Triethylamine Buffer mixture (75:25 v/v, pH 6.1) was used at 1 ml/min flow rate and Agilent ZORBAX Eclipse XDB C18 (250 mm × 4.6 mm, 5 μm) column. Results: At 231 nm as wavelength, high-pitched peaks of Tigecycline (Tig) and its impurities (1and2) were detected at 6.55, 8.73 and 4.87 min correspondingly. The linearity of tigecycline and its impurities (impurity-1 and 2 and) were estimated with ranging from 75–450 µg/ml for Tigecycline and 1–6 µg/ml for both impurity 1 and 2. The corresponding recognition limits (LOD and LOQ) of the tigecycline and its impurities were originated to be (1.37,0.047 and 0.071 µg/ml) and (4.15, 0.143 and 0.126 µg/ml). Conclusion: The technique was effectively stretched for stability signifying studies under different stress conditions. Justification of the method was done as per the current ICH guidelines.

Development and Greenness Assessment of HPLC Method for Studying the Pharmacokinetics of Co-Administered Metformin and Papaya Extract

Foods with medical value have been proven to be beneficial, and they are extensively employed since they integrate two essential elements: food and medication. Accordingly, diabetic patients can benefit from papaya because the fruit is low in sugar and high in antioxidants. An RP-HPLC method was designed for studying the pharmacokinetics of metformin (MET) when concurrently administered with papaya extract. A mobile phase of 0.5 mM of KH2PO4 solution and methanol (65:35, v/v), pH = 5 ± 0.2 using aqueous phosphoric acid and NaOH, and guaifenesin (GUF) were used as an internal standard. To perform non-compartmental pharmacokinetic analysis, the Pharmacokinetic program (PK Solver) was used. The method’s greenness was analyzed using two tools: the Analytical GREEnness calculator and the RGB additive color model. Taking papaya with MET improved the rate of absorption substantially (time for reaching maximum concentration (Tmax) significantly decreased by 75% while maximum plasma concentration (Cmax) increased by 7.33%). The extent of absorption reduced by 22.90%. Furthermore, the amount of medication distributed increased (30.83 L for MET concurrently used with papaya extract versus 24.25 L for MET used alone) and the clearance rate rose by roughly 13.50%. The results of the greenness assessment indicated that the method is environmentally friendly. Taking papaya with MET changed the pharmacokinetics of the drug dramatically. Hence, this combination will be particularly effective in maintaining quick blood glucose control.

Analytical quality by design approach to RP-HPLC method development and validation for simultaneous estimation of esomeprazole and naproxen in modified-release dosage form

Background The present work describes the development and validation of a new, specific, accurate, and precise stability-indicating RP-HPLC method for the simultaneous estimation of Esomeprazole (ESP) and Naproxen (NAP) in modified-release bi-layer tablet dosage form. Analytical Quality by Design concept was implemented through the method development exercise to establish the robustness of the method. Results Method development was performed on C18, 250 × 4.6 mm ID, and 5 µm particle size column with 10 µl injection volume using a photodiode array (PDA) detector to monitor the detection at 280 nm. The mobile phase consisted of the buffer: methanol at a ratio of 50: 50 (v/v), and the flow rate was maintained at 1.5 ml/min, and the column oven temperature was maintained at 30 °C. The retention times for NAP and ESP were found 5.9 ± 0.1 and 8.9 ± 0.1 min, respectively. The method was validated in terms of system suitability, specificity, accuracy, linearity, precision, and solution stability. Linearity was observed over the range of concentration 8–12 µg/ml for ESP and 200–300 µg/ml for NAP, and the correlation coefficient (R2) was found excellent > 0.999. The method was specific to ESP and NAP, and the peak purity was found 99.97% for ESP and 100.00% for NAP. The method was precise and had %RSD less than 2. Recovery study for accuracy with placebo was found in the range of 99.63–100.36% for ESP and 99.91–100.43% for NAP. Conclusion This proposed fast, reliable, cost-effective method can be used as a quality control tool for the simultaneous determination of Esomeprazole and Naproxen in routine laboratory analysis. Graphical Abstract