Optimization Of Alkaloid Extraction From Lotus Leaves By Response Surface Methodology

Alkaloids usually refer to alkaline nitrogen-containing compounds found in living organisms.Lotus leaves have high nutritional value and pharmacological effects.Lotus leaves can clear fire,dampness,stop bleeding,lower blood fat and blood sugar,and sputum blood.Used in medicine,health care products,food,cosmetics and other industries.There are many methods for extracting total alkaloids from lotus leaves.Among them,ultrasonic assisted extraction has many advantages such as reducing time consumption,saving solvent,and improving efficiency.In this paper,ultrasonic extraction-assisted extraction method was used to extract total alkaloids from lotus leaves.Through the research on its extraction process,an effective green extraction process was established.In this article,ultrasonic extraction of total alkaloids from lotus leaves is used to select the best extraction solvent through comparison experiments of five solvent extraction rates.Then single factor test,5 factors are p H,extraction time,ethanol volume fraction,solid-liquid ratio and extraction temperature.The three most influential factors were selected using Design-Expert software to optimize the response surface to determine the optimal extraction process conditions.The macroporous resin is then used to separate the crude alkaloid extract of the lotus leaf.Static experiments are used to examine the resin model,The dynamic test is used to investigate the effect of resin type,sample volume,sample flow rate,sample solution concentration,p H,eluent selection,and elution flow rate.Finally,the total alkaloids of lotus leaves were purified by ethyl acetate,and the total alkaloids of lotus leaves were analyzed by HPLC.The main experimental results are as follows:1.The optimum process conditions for ultrasonic extraction were: solvent p H 2.0,ultrasonic extraction time 65.31 min,ethanol volume fraction 71.1%,solid-liquid ratio 1:32.1(g/m L),temperature 70?.2.The optimum process conditions for adsorption and separation of macroporous resin: resin model is NKA-9,sample volume is 10 m L,sample solution flow rate is 1m L/min,sample solution concentration is 2mg/m L,p H is 10,Eluent concentration is 60% and the elution flow rate was 1 m L/min.Finally,the total alkaloid extract of lotus leaf was detected by high performance liquid chromatography HPLC,it was found that the extract contained the Nuciferin component.After a series of optimizations of extraction and purification conditions,a higher concentration of total alkaloids in lotus leaves can be obtained,which provides theoretical guidance for later industrial production.