RP-HPLC method for the simultaneous quantitation of boeravinone E and boeravinone B in Boerhaavia diffusa extract and its formulation.

A high-performance liquid chromatography method was developed and validated for the simultaneous quantitation of two major rotenoids, boeravinone E and boeravinone B, in Boerhaavia diffusa extract and its formulation. Chromatographic separation was carried out on an Inertsil ODS-3 column by using gradient mobile phase containing 0.1% v/v orthophosphoric acid in water and acetonitrile. The detection was carried out at 276 nm. The method was validated for specificity, precision, accuracy and robustness. The linearity (r(2) = 0.9989 and 0.9991) was found to be in the range of 7.26-35.75 µg mL(-1) and 2.20-11.00 µg mL(-1) for boeravinone E and B, respectively. The percent recovery observed from the extract sample was 95.22-95.83.

Protective effect of Luffa acutangula extracts on gastric ulceration in NIDDM rats: role of gastric mucosal glycoproteins and antioxidants.

OBJECTIVE: To study the comparative gastroprotective effect of Luffa acutangula methanolic extract (LAM) and aqueous extract (LAW) on type II diabetes rats. METHODS: Streptozotocin (65 mg/kg, i.p.) along with nicotinamide (120 mg/kg, i.p.) was used to induce non insulin dependent diabetes mellitus (NIDDM) in rats. A daily oral dose of aspirin (200 mg/kg, i.p.) was administered for initial seven days to induce gastric ulcerations in the diabetic rats. LAM and LAW were administered orally in the doses of 100, 200 and 400 mg/kg once daily for 21 days. Glibenclamide and ranitidine were used as standards for comparing the antidiabetic and antiulcer effect respectively. RESULTS: LAM significantly (P<0.01) increased mucosal glycoprotein and antioxidant enzyme level in gastric mucosa of diabetic rats than LAW (P <0.05). LAM was efficient in reversing the delayed healing of gastric ulcer in diabetic rats close to the normal level. LAM exhibited better ulcer healing effect than glibenclamide and LAW, because of its both antihyperglycemic and mucosal defensive actions. CONCLUSIONS: Thus, LAM is proved to be a better alternative for treating gastric ulcers co-occurring with diabetes.

Validated TLC method for simultaneous quantitation of kutkoside and picroside-I from Kutki extract.

INTRODUCTION: The two iridoid glycosides kutkoside and picroside-I are the active hepatoprotective principles of Picrorhiza kurroa Royle ex Benth (Scrophulariaceae), commonly known as Kutki. Quantitation of these phytoconstituents is important for the routine quality control of Kutki extract. OBJECTIVE: To develop and validate a simple, precise and rapid thin-layer chromatography (TLC) method for the simultaneous quantitation of kutkoside and picroside-I in Kutki extract. METHODOLOGY: The analysis was performed on a TLC precoated silica gel 60 F(254) plate with ethyl acetate:methanol:glacial acetic acid:formic acid (25:5:1:1, v/v/v/v) as mobile phase. Densitometric evaluation of kutkoside and picroside-I was carried out at 265 nm and the mobile phase showed good resolution with R(f) values 0.42 ± 0.03 and 0.61 ± 0.03 for kutkoside and picroside-I, respectively. The method was validated in terms of specificity, linearity, accuracy and precision. RESULTS: The content of kutkoside and picroside-I was found to be 2.18 and 1.90%, respectively, and was comparable with those obtained by HPLC. The linearity was found to be in the range of 80-480 ng/spot for both kutkoside and picroside-I. The average recovery values were found to be 96.5 and 96.0% for kutkoside and picroside-I, respectively. CONCLUSION: The developed method was found to be relatively simple, precise and reproducible for the simultaneous quantitation of kutkoside and picroside-I. The method does not employ any derivatisation procedure and can be used as a quality control tool for the routine analysis of commercial Kutki extracts.

Development and validation of a method for densitometric analysis of berberine in herbal extract and polyherbal formulation.

OBJECTIVE: To develop a new high-performance thin-layer chromatography (HPTLC) method for the quantification of berberine in herbal extract and pharmaceutical dosage form. MATERIALS AND METHODS: The HPTLC was performed on aluminium foil plates coated with 200 µm silica gel 60F(254). Linear ascending development with toluene:ethyl acetate:formic acid:methanol 9:9:3:1 (v/v/v/v) was performed at room temperature (25 ± 2°C) in a twin-trough glass chamber saturated with mobile-phase vapour. Compact bands (R(F) 0.58 ± 0.02) were obtained for berberine. Spectrodensitometric scanning was performed in fluorescence mode at 350 nm. The method was validated for precision, recovery, robustness, specificity, and detection and quantification limits, in accordance with International Conference on Harmonization guidelines. RESULTS: Linear regression analysis of the calibration plots showed a good linear relationship (r(2) = 0.9996 ± 0.0001) between peak area and concentration in the range 10-100 ng/band, respectively. The limits of detection and quantification were 2.8 and 9.3 ng/band. The recovery of the method was 98.5-100.6%. CONCLUSION: The above method was a rapid and cost-effective quality-control tool for routine analysis of berberine in herbal extracts and in pharmaceutical dosage form.

Transient receptor potential V1 regulates activation and modulation of transient receptor potential A1 by Ca2+.

The transient receptor potential A1 (TRPA1) channel contributes to nociceptive signaling in certain pain models. It has been suggested that Ca(2+), which activates and modulates TRPA1, could play a critical regulatory role in this process. Since TRPA1 and transient receptor potential V1 (TRPV1) channels are co-expressed and interact in neurons, we investigated whether activation and modulation of TRPA1 by Ca(2+) is regulated by TRPV1. Cell-attached recordings showed that TRPA1 is activated by extracellular Ca(2+) ([Ca(2+)](e)) in concentration-response fashion. This activation, especially by 2 mM [Ca(2+)](e) was substantially suppressed by co-expression with TRPV1. Inside-out recordings demonstrated that intracellular Ca(2+) ([Ca(2+)](i))-triggered activation of TRPA1 was attenuated by the presence of TRPV1 only at 2 mM [Ca(2+)](e), but not in Ca(2+)-free conditions. Further, depletion of internal Ca(2+) stores by thapsigargin generated TRPA1-mediated currents, which is affected by TRPV1 in both Chinese hamster ovary cells and sensory neurons. Since mustard oil current (I(MO)) is modulated by [Ca(2+)](e), we next examined whether alterations in the Ca(2+)-permeability of TRPV1 by mutating Y671 effect I(MO) properties. First it was demonstrated that the mutations in TRPV1 did not affect association of the TRPA1 and TRPV1 channels. However, these TRPV1 mutations, particularly Y671K, altered the following characteristics of TRPA1: magnitude of I(MO) in presence and absence of [Ca(2+)](e); the influence of [Ca(2+)](e) on the voltage-dependency of I(MO), and open probability of single-channel I(MO). In summary, activation of TRPA1 by [Ca(2+)](e) and [Ca(2+)](i) is controlled by the TRPV1 channel, and characteristics of I(MO) depend on Ca(2+) permeability of the TRPV1 channel.