title: In vivo wound healing activity and phytochemical screening of the crude extract and various fractions of Kalanchoe petitiana A. Rich (Crassulaceae) leaves in mice.
abstract: BACKGROUND
  The leaves of Kalanchoe petitiana A. Rich (Crassulaceae) are used in Ethiopian folk medicine for treatment of evil eye, fractured surface for bone setting and several skin disorders including for the treatment of sores, boils, and malignant wounds.
  
  
  OBJECTIVE
  In order to scientifically prove the claimed utilization of the plant, the effects of the extracts and the fractions were investigated using in vivo excision, incision and dead space wound models.
  
  
  METHODS
  Mice were used for wound healing study, while rats and rabbit were used for skin irritation test. For studying healing activity 80% methanolic extract and the fractions were formulated in strength of 5% and 10%, either as ointment (hydroalcoholic extract, aqueous and methanol fractions) or gel (chloroform fraction). Oral administration of the crude extract was used for dead space model. Negative controls were treated either with simple ointment or sodium carboxyl methyl cellulose xerogel, while positive controls with nitrofurazone (0.2 w/v) skin ointment. Negative controls for dead space model were treated with 1% carboxy methyl cellulose. Parameters, including rate of wound contraction, period of complete epithelializtion, hydroxyproline contents and skin breaking strength were evaluated.
  
  
  RESULTS
  Significant wound healing activity was observed with ointment formulated from the crude extract at both 5% and 10% concentration (p<0.01) compared to controls in both excision and incision models. In dead space model, 600 mg/kg (p<0.01) but not 300 mg/kg significantly increased hydroxyproline content. Fractions showed variable effect, with the chloroform fraction lacking any significant effect. Both 5% and 10% formulations of the aqueous and methanolic fractions significantly increased wound contraction, decreased epithelializtion time and increased hydroxyproline content in excision wound model (p<0.05) as compared to controls. These fractions were also endowed with higher skin breaking strength in incision wound model (p<0.01).
  
  
  CONCLUSIONS
  The present study provided evidence that the leaves of Kalanchoe petitiana A. Rich possess remarkable wound healing activities supporting the folkloric assertion of the plant. Fractionation revealed that polar or semi polar compound may play vital role, as both aqueous and methanolic fractions were endowed with wound healing activity.
authors.affiliation: Addis Ababa University, Department of Pharmacology and Clinical Pharmacy, School of Pharmacy, Addis Ababa 9086, Ethiopia.
authors.forename: Awol
authors.initials: A
authors.lastname: Mekonnen
authors.forename: Temesgen
authors.initials: T
authors.lastname: Sidamo
authors.forename: Kaleab
authors.initials: K
authors.lastname: Asres
authors.forename: Ephrem
authors.initials: E
authors.lastname: Engidawork
mesh_terms: D000818:Animals; D003879:Dermatologic Agents / Q000737:chemistry / Q000627:therapeutic use*; D006909:Hydroxyproline / Q000378:metabolism; D031962:Kalanchoe; D007928:Lethal Dose 50; D051379:Mice; D009824:Ointments; D010936:Plant Extracts / Q000737:chemistry / Q000627:therapeutic use*; D018515:Plant Leaves; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000187:drug effects / Q000293:injuries / Q000378:metabolism; D013718:Tensile Strength; D023382:Toxicity Tests, Acute; D014945:Wound Healing / Q000187:drug effects*
chemical_list: D003879:Dermatologic Agents; D009824:Ointments; D010936:Plant Extracts; D006909:Hydroxyproline