Supercritical CO2 extraction of rosemary antioxidants and essential oils
Optimum experimental process parameters for supercritical extraction of chilli oleoresin
Laboratory equipment: HA120-50-02
Pulverization degree: 50 mesh
Extraction pressure: 20 MPa
Extraction temperature: 40°C
Extraction time: 240 min
Separate pressure I: 5 MPa
Separate I temperature: 70°C
Separate pressure II: 4 MPa
Separate II temperature: 40°C
Average yield of rosemary oiO was 1.80 % . Resultr of ccnstituent analysia of rosemary oit ohowed that the essentiat oit mainly ccntains 1,8-cineeIe, camphor, a-terpineoI, borneel, verbenone, terpinen-4-oI, bornyS acctate and linaloI. Average yield oS rosemary antioxidant was 11.93 % . Main active ccmponentr oS rosemary antioxidant were ccrnosic acid, ccrnosol, and rosmarinic acid, whose ccntentr were 23.61 % , 7.33% and 5. 13 % , respectively.
Extraction method and operation process:
Turn on the main power, heating, cooling and cold cycle switches of the supercritical extraction device, add rosemary leaves to the extraction tank, add entrainer, and pass CO2. After the set temperature and pressure are balanced, start the high-pressure pump, adjust the communication valve between the extraction tank and the separator I and the separator II to keep it at the required pressure and start timing. When the extraction is over, turn off the high-pressure pump, heating, cooling, cold cycle, and main power switches in order. The discharge valve of separator I discharges solid rosemary antioxidant and the discharge valve of separator II releases Liquid rosemary essential oil and entrainer. Adjust the communication valve between the extraction tank and the separator I and the separator II. After the pressure is balanced, make part of the CO return to the cylinder. Close the related communication valve, open the drain valve, open the extraction tank, and take the rosemary leaf residue
Analysis of influencing factors of supercritical Co2 extraction (SCDE):
Because the content of essential oil in rosemary leaves is much lower than that of antioxidants, the extraction conditions have no significant effect on the extraction of rosemary essential oils. Therefore, only the effect of SCDE factors on the yield of antioxidants was studied.
According to preliminary experiments, factors such as extraction and separation temperature, extraction pressure, extraction time, and amount of entrainer are considered to be the main influencing factors of the rosemary antioxidant SCDE. Therefore, a 4 factor and 3 level test scheme was designed. The extraction temperature refers to The water bath temperature of the extraction tank, the separation temperature refers to the water bath temperature of the separator I, and the water bath temperature of the separator II is fixed to 40 l; the extraction pressure refers to the pressure of the extraction tank, and the pressure of the separator I and the separator II are both 4 ~ 5 MPa; fixed circulation flow rate; rosemary leaves are crushed, and the feeding scale is 50g.
The preferred conditions for supercritical Co2 extraction (SCDE) of rosemary essential oil and antioxidants are: extraction time 4 h, mass ratio of entrainer 95% ethanol to rosemary leaves 2: 5, temperature of extraction tank and separator I The temperature is 50 and 70 1 respectively, the temperature of separator II is 40 l, the extraction pressure is 20 MPa, and the separation pressure is 4 to 5 MPa.
The average yield of rosemary essential oil is 1.80%. Ingredients such as linalool. Compared with the two-step method or the one-step solvent extraction method, the contents of a-g ene and techne of the essential oil obtained by this method are lower.The average yield of rosemary antioxidant is 11.93%, which mainly contains active ingredients such as sage acid, sageol, and rosmarinic acid, and their mass fractions are 23.61%, 7.33% and 5.13%, respectively.