Topical formulations of serratiopeptidase: development and pharmacodynamic evaluation

Abstract

Serratiopeptidase, an enzyme derived from Serratia marcescences strain E-15 (ATCC 21074), present in the gut wall of the silk worm possesses anti-inflammatory properties, and can prove to be a suitable alternative to commonly used non steroidal antiinflammatory agents. Being sensitive to gastric degradation, serratiopeptidase is conventionally given orally in the form of enteric coated tablet formulations. Topical formulations of serratiopeptidase would be useful to treat local inflammations and may prove to be more effective compared to non steroidal antiinflammatory agents. The present study investigates the feasibility of developing topical preparations of serratiopeptidase in the form of ointments and gels. Excipient compatibility of serratiopeptidase with various excipients and polymers, formulation development, characterization and stability studies have been carried out. Stable formulation was evaluated for anti-inflammatory activity by oxazolone induced ear edema method in mice and allergenic potential by passive cutaneous anaphylaxis.

Keywords: Antiinflammatory; gel; ointment; serratiopeptidase.

Fig. 1

Solution state stability at 37° and at Room temperature The solution state stability was given in % activity of SRP at (A) 37° where, a comparision between distilled water (-◆-), Tris Buffer pH 7.0 (-■-) and phosphate buffer pH 7.0 (-▲-) and (B) at room temperature has been given.

Fig. 2

In vitro release profile of SRP, XG gel and ointment (P42) formulation Percentage release profile of plain SRP (-■-) and its xanthan gum (XG) gel (-◆-) and polyethylene glycol glyceryl monooleate (PEGGMO) ointment (-▲-)

Fig. 3

Percent edema after treatment of standard and test ointment formulation Treatment group is polyethylene glycol glyceryl monooleate (PEGGMO) ointment and error bars represents standard deviation (n=6)

Fig. 4

PCA reaction in the standard ovalbumin and test formulations treated albino mice. PCA reaction of Standard ovalbumin antigen in upper row showed dark blue coloured circled patches, Test formulation (polyethylene glycol glyceryl monooleate, PEGGMO ointment) showed considerable reduction in dark circles. The test was carried out with undiluted serum and various dilution ratios of 1:1, 1:2 and 1:4