Vivekananda Mandal

Design of Experiment Approach for the Process Optimisation of Microwave Assisted Extraction of Lupeol from Ficus racemosa Leaves Using Response Surface Methodology

INTRODUCTION Triterpenoids are a group of important phytocomponents from Ficus racemosa (syn. Ficus glomerata Roxb.) that are known to possess diverse pharmacological activities and which have prompted the development of various extraction techniques and strategies for its better utilisation. OBJECTIVE To develop an effective, rapid and ecofriendly microwave-assisted extraction (MAE) strategy to optimise the extraction of a potent bioactive triterpenoid compound, lupeol, from young leaves of Ficus racemosa using response surface methodology (RSM) for industrial scale-up. MATERIAL AND METHOD Initially a Plackett-Burman design matrix was applied to identify the most significant extraction variables amongst microwave power, irradiation time, particle size, solvent:sample ratio loading, varying solvent strength and pre-leaching time on lupeol extraction. Among the six variables tested, microwave power, irradiation time and solvent-sample/loading ratio were found to have a significant effect (P < 0.05) on lupeol extraction and were fitted to a Box-Behnken-design-generated quadratic polynomial equation to predict optimal extraction conditions as well as to locate operability regions with maximum yield. RESULTS The optimal conditions were microwave power of 65.67% of 700 W, extraction time of 4.27 min and solvent-sample ratio loading of 21.33 mL/g. Confirmation trials under the optimal conditions gave an experimental yield (18.52 µg/g of dry leaves) close to the RSM predicted value of 18.71 µg/g. CONCLUSION Under the optimal conditions the mathematical model was found to be well fitted with the experimental data. The MAE was found to be a more rapid, convenient and appropriate extraction method, with a higher yield and lower solvent consumption when compared with conventional extraction techniques.

A Brief Understanding of Process Optimisation in Microwave-assisted Extraction of Botanical Materials: Options and Opportunities with Chemometric Tools

INTRODUCTION Extraction forms the very basic step in research on natural products for drug discovery. A poorly optimised and planned extraction methodology can jeopardise the entire mission. OBJECTIVE To provide a vivid picture of different chemometric tools and planning for process optimisation and method development in extraction of botanical material, with emphasis on microwave-assisted extraction (MAE) of botanical material. METHODS A review of studies involving the application of chemometric tools in combination with MAE of botanical materials was undertaken in order to discover what the significant extraction factors were. Optimising a response by fine-tuning those factors, experimental design or statistical design of experiment (DoE), which is a core area of study in chemometrics, was then used for statistical analysis and interpretations. RESULTS In this review a brief explanation of the different aspects and methodologies related to MAE of botanical materials that were subjected to experimental design, along with some general chemometric tools and the steps involved in the practice of MAE, are presented. A detailed study on various factors and responses involved in the optimisation is also presented. CONCLUSION This article will assist in obtaining a better insight into the chemometric strategies of process optimisation and method development, which will in turn improve the decision-making process in selecting influential extraction parameters.

HPTLC evaluation of oleanolic acid and ursolic acid from the methanol extract of Wattakaka volubilis

Abstract Objective To find out the secondary metabolites present in the methanol extract of Wattakaka volubilis (W. volubilis). Methods High performance thin layer chromatography method for the quantification of triterpenoids in soxhlet methanol extract of W. volubilis is described by densitometric scanning. The linear regression data from the calibration curve was plotted over the range of 10–25 μg/mL, r2 = 0.992 46, 0.950 42 respectively. A mixture of toluene: methanol (9:1) was used as mobile phase for oleanolic acid were petroleum ether: chloroform: ethyl acetate: methanol (4:1:0.1:0.1) were used for ursolic acid. Results The results showed that the presence of oleanolic acid and ursolic acid in methanol extract. The content found to be 218.30 ng and 509.99 ng/10 mg of extract. Conclusion For conclusion, above study scientifically validated as a useful traditional medicine with the identification of bioactive secondary metabolites.

Strategizing method optimization of microwave-assisted extraction of plant phenolics by developing standard working principles for universal robust optimization

This article is focused on making the optimization of microwave-assisted extraction (MAE) of phenolics from leaves easier by proposing some basic check points or riders which will provide help for beginners and industries in the quick adoption of such technologies for the large scale extraction of nutraceuticals. The Taguchi L9 model was used for the optimization of the MAE conditions for phenolic extraction from the leaves of Taraxacum officinale. Total phenolic content was used as the performance monitoring parameter for the proposed extraction model. The study reports 160 W microwave power, 6 min extraction time, 80 °C temperature and 10 min preleaching time as the optimized MAE conditions. Kinetic plot mapping, checks for chromatogram matching, SEM studies, bioactivity profiling, nutraceutical profiling, degradation profiling and environmental impact studies were the other supporting parameters used for arriving at the different check points proposed in this article. Rutin, naringenin, chlorogenic acid, ellagic acid, gallic acid, luteolin, quercetin and ferulic acid were the standard phenolics/flavonoids that were identified in the extract through HPTLC. The efficiency of MAE in terms of TPC was found to be more than 60% higher than that observed by Soxhlet extraction, with significant improvement in nutraceutical content and bioactivity as evaluated through total antioxidant capacity and anti-inflammatory activity.

Fundamentals of Microwave-Based Sample Preparation for Plant-Based Drug Discovery

Abstract This chapter vividly depicts the strategic steps involved in performing microwave-assisted extraction (MAE) of plant bioactives through well-designed scientific frequently asked questions. The chapter is believed to be a strategic operating manual for first-timers in the area of extraction of botanicals with emphasis on MAE and also aims to attract more researchers to this area. The chapter also serves as a one-stop solution center for all issues related to MAE of plant bioactives.

Extraction of phenolic principles: value addition through effective sample pretreatment and operational improvement

Edible plants generally green leafy vegetables contain bioactive Phenolics and antioxidant principles which are important in maintaining the oxidative balance of the human body and are used widely as dietary supplements. Optimal extraction of such principles is the need of the hour for the nutraceutical industries. The work presents three innovative sample pretreatment such as providing additional heat to the thimble, use of microwave pretreated sample and pretreatment with acoustic waves. These modifications are intended to improve the working efficiency and output of traditional Soxhlet extraction and make it at par with modern extraction techniques. Extraction of plant phenolics/flavonoids from edible leaves of Amaranthus viridis Linn (Amaranthaceae) and their subsequent HPTLC mapping was used as the performance indicator. Check of nutraceutical and biological integrity upon application of such pretreatment methods was performed. SEM analysis was carried out to get a true inside of the exctraction events occurring internally. Such findings can be helpful for small scale industries who cannot afford costlier modern extraction methods. Four assumptions have been proposed which can be a critical in impriving any extraction method.