Abstract: The purpose of the present study was to develop an optimized process for extracting the dried Calendula officinalis flowers belonging to the family Compositae, being used extensively in many traditional formulations which are of great demand for this herb world wide. Optimizing the methodology of extraction of this herb could minimize the duration of extraction, improve yield, and have better control over the different parameters involved in the process, making the process highly effective and cost effective. Plackett-Burman design was employed for extracting Calendula officinalis. The studied independent variables are Type of apparatus (X1), Powder size, (X2), Duration of extraction(X3), Type of water for extraction (X4), Method of removal of solvent(X5), and Method of drying the extract (X6). Percentage yield was considered as dependent variable. The main effect and interaction terms were quantitatively evaluated using a mathematical model. The results indicate that factor X1 and X2 significantly affected the percentage yield. But the use of different type of water was found to be insignificant. Regression analysis and numerical optimization were performed to identify the best extraction method. The predicted values agreed well with the experimental values, and the results demonstrate the practicability of the model in the development of extraction process.
Calendula officinalis Linn (family Compositae), commonly known as 'Marigold' is a well known herb in India. It is native to Europe and is cultivated in temperate regions around the world. It contains phytoconstituents such as saponins, flavonoids, mucilage, essential oil, bitter principle, resins and steroidal compounds.
Calendula exhibits wide range of pharmacological and therapeutic properties and has been used extensively in Ayurveda, homeopathy and Traditional Chinese medicine for both internal as well as external preparation. Is reported to be having wound healing, immunomodulatory, spasmogenic and spasmolytic, antimutagenic, anti-inflammatory, antioxidant, antibacterial, antiulcer, anti HIV, antitumorienic, antiviral and Hepato-protective activities. Calendula is also very popular for its protective properties such as skin moisturizing and depigmentation.