title: Comparative assessment of extraction methods and quantitative estimation of luteolin in the leaves of Vitex negundo Linn. by HPLC.
abstract: OBJECTIVE
  To find out the ideal organic solvent and extraction technique for the isolation of luteolin from the leaves of Vitex negundo Linn. (V. negundo) by quantitative estimation of luteolin through high performance liquid chromatography (HPLC) method.
  
  
  METHODS
  The leaves of V. negundo were identified by a botanist, cleaned, dried under shade and powdered. Maceration, reflux, Soxhlet and ultrasound assisted extraction techniques were used for the extraction of luteolin from the leaves by using four different solvents of varying polarity such as methanol, ethanol, chloroform, and dichloromethane. A simple HPLC method was used to determine the quantity of luteolin in each sample extract.
  
  
  RESULTS
  The calibration plot of standard luteolin showed a linear relationship in the concentration range of 100-500 μg/mL with a correlation coefficient, r(2) of 0.998. The methanolic extract was found to contain highest amount of luteolin and among various techniques employed for extraction and isolation of luteolin, reflux technique was observed to be the most efficient.
  
  
  CONCLUSIONS
  Based on the HPLC results, it can be concluded that reflux technique using methanol is better than the other extraction techniques and should be preferred for the extraction and isolation of luteolin from V. negundo leaves extract in research labs or industries.
authors.affiliation: Department of Pharmacognosy & Phytochemistry, Faculty of Pharmacy, Jamia Hamdard, New Delhi-110062, India.
authors.forename: Lubna
authors.initials: L
authors.lastname: Abidin
authors.affiliation: Department of Pharmacognosy & Phytochemistry, Faculty of Pharmacy, Jamia Hamdard, New Delhi-110062, India. Electronic address: mmujeebzaidi@gmail.com.
authors.forename: Mohd
authors.initials: M
authors.lastname: Mujeeb
authors.affiliation: Department of Pharmacognosy & Phytochemistry, Faculty of Pharmacy, Jamia Hamdard, New Delhi-110062, India.
authors.forename: Showkat Rasool
authors.initials: SR
authors.lastname: Mir
authors.affiliation: Department of Pharmacy, Oman Medical College, Muscat, Oman.
authors.forename: Shah Alam
authors.initials: SA
authors.lastname: Khan
authors.affiliation: Health Information Technology Department, Jeddah Community College, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia.
authors.forename: Aftab
authors.initials: A
authors.lastname: Ahmad
keywords: Extraction techniques; HPLC; Luteolin; Vitex negundo