Formulation and evaluation of thermoreversible,mucoadhesive in situ intranasal gel of rizatriptan benzoate

The present study was aimed to formulate and evaluate in situ thermoreversible intranasal gel of an antimigraine drug rizatriptan benzoate. The poloxamer 407 and carbopol 934 were used as thermoreversible and mucoadhesive polymers respectively. The gels were prepared with cold method. The phase transition temperature was determined with visual method. The gels were evaluated for their pH, mucoadhesive strength, in vitro release and ex vivo drug permeation through goat nasal mucosa. The histopathological study of the nasal mucosa was carried out to check for its damage during drug permeation. The 18 % w/v poloxamer solution was found to be showing phase transition at physiologic conditions (34–35 °C). As the percentage of carbopol 934 was increased from 0.1 to 0.5 % w/v the gelling temperature was found to be decreased. All formulations were showing mucoadhesive strength above 4,000 dynes/cm². Drug permeation studies have indicated that the drug permeation rate can be increased by using carbopol 934 above 0.3 % w/v concentration. The histopathological evaluation of nasal mucosa after drug permeation study has not shown any evidence of damage. Thus in situ thermoreversible mucoadhesive gel of rizatriptan benzoate can be a promising approach to treat migraine.     

Development and Validation of UV Spectrophotometric Method to Study Stress Degradation Behaviour of Rizatriptan Benzoate

Rizatriptan benzoate is a 5HT 1B/1Dreceptor agonist which is prescribed for the treatment of migraine.In the present study new,simple,specific ultraviolet spectrophotometric method for rizatriptan benzoate was developed and validated.Forced degradation studies were carried out in acidic,alkaline and neutral pH conditions.The absorbance maxima peak was found to be 224 nm and linearity was observed in the concentration range of 0.5~2.5μg·mL-1 with regression coefficient value of 0.998 8.The method was validated and found to be precise.The percent recovery for rizatriptan benzoate was found to be 98.576±0.202.The bulk drug was found to be stable in neutral and acidic pH conditions but got degraded in 1N NaOH solution.     

Antioxidant and antimicrobial study of Schefflera vinosa leaves crude extracts against rice pathogens

Plant extracts are one of the best possible sources of bioactive molecules, and are being used globally as an antioxidants and natural antimicrobial compounds. In current study, Schefflera vinosa leaves extract was prepared through Soxhlet extraction procedure using methanol and chloroform as solvents. The extract was investigated for total antioxidant, phenolic and flavonoid contents, free radical scavenging and antimicrobial activities. The free radical scavenging activities were evaluated through 2,2- diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzotiazolin-6-sulfonic acid (ABTS) and Ferric-reducing/ antioxidant power (FRAP) assay. The antimicrobial activity of extract was determined through poisoned food method. The methanolic extract has exhibited high antioxidant, phenolic, and flavonoid activities compared to chloroform extract. Similarly, free radical scavenging activities (ABTS, DPPH and FRAP) were higher in methanolic extract. Further, Fourier-Transform Infrared Spectroscopy (FTIR) used to determine the functional group and Gas chromatography-mass spectrometry (GC–MS) to elucidate volatile composition of the crude extract. Different functional group like N-H, O-H, C-O, C-N, C-H, C=O, C≡C and C-O-H presence indicate the existence of many metabolites in the extracts. GC–MS study identified 61 compounds and subsequently, these molecules were screened virtually using DockThor. Furthermore, antimicrobial study was confirmed against rice pathogens like Magnaporthe oryzae (M. oryzae) and Xanthomonas oryzae pv. oryzae (Xoo). Molecular docking study further suggested that phytomolecules (3-Isopropoxy-1,1,1,7,7,7-hexamethyl-3,5,5-tris (trimethylsiloxy) tetrasiloxane, and 2-Methoxy-5-methylthiophene) targets Histone Deacetylase (HDAC) of M. oryzae and Peptide Deformylase (PDF) of Xoo, which could inhibit their growth. Hence, this study indicated that Schefflera vinosa extracts could be an important ingredient as an antioxidant as well as antimicrobial agent against rice pathogens.