阅读说明：本技术 一种利用山茶属植物果皮提取儿茶素和表儿茶素的方法 (Method for extracting catechin and epicatechin from pericarp of plant of Camellia ) 是由 陈丰林 谭海波 郭新红 于 2021-04-07 设计创作，主要内容包括：本发明公开了一种利用山茶属植物果皮提取儿茶素和表儿茶素的方法。本发明方法利用废弃山茶属植物果皮进行提取得到儿茶素和表儿茶素,不仅能解决目前儿茶素和表儿茶素提取中存在的含量低、杂质多、难以纯化、生产成本高、色素难以去除等产业化生产问题,并适用于大规模生产；而且将进一步推动废弃油茶果皮的资源再利用,解决茶油生产废弃物的困扰问题。(The invention discloses a method for extracting catechin and epicatechin from camellia plant pericarp. The method of the invention extracts the catechin and the epicatechin by using the waste camellia plant peel, not only can solve the industrial production problems of low content, more impurities, difficult purification, high production cost, difficult pigment removal and the like in the prior extraction of the catechin and the epicatechin, but also is suitable for large-scale production; but also further promotes the resource recycling of the waste oil tea peel, and solves the problem of the puzzlement of the tea oil production waste.)

1. A process for extracting catechins and epicatechins, comprising the steps of:

a. collecting pericarp of plant of Camellia, physically crushing, extracting with water and/or ethanol, separating extractive solution, concentrating under reduced pressure, adding ethanol, dispersing, and filtering to obtain filtrate; carrying out rotary evaporation and vacuum concentration on the filtrate, and then carrying out freeze drying to obtain a crude tea polyphenol mixture;

b. dispersing the crude tea polyphenol mixture with ethanol water solution, extracting with mixed solvent of ethyl acetate and n-hexane, collecting organic phase, washing with water and saturated NaCl water solution, drying with anhydrous sodium sulfate, filtering, rotary evaporating the filtrate, and vacuum concentrating to obtain catechin and epicatechin.

2. The method according to claim 1, wherein the leaching with water and/or ethanol of step a is multiple leaching with water, ethanol or ethanol aqueous solution of any concentration.

3. The method of claim 2, wherein the aqueous ethanol solution is a 95% ethanol aqueous solution by volume fraction.

4. The method according to claim 1, wherein the step b specifically comprises: dispersing the crude tea polyphenol mixture with 50% ethanol aqueous solution by volume fraction, extracting with mixed solvent of ethyl acetate and n-hexane at volume ratio of 1:1, collecting organic phase, washing with water and saturated NaCl aqueous solution, drying with anhydrous sodium sulfate, filtering, rotary evaporating the filtrate, and vacuum concentrating to obtain catechin and epicatechin.

5. The method according to claim 4, wherein the step b specifically comprises: dispersing the crude tea polyphenol mixture with 50% ethanol aqueous solution by volume fraction, extracting with mixed solvent of ethyl acetate and n-hexane at volume ratio of 1:1 for 3 times, collecting organic phase, washing with water and saturated NaCl aqueous solution for 1 time respectively, drying with anhydrous sodium sulfate, filtering, rotary evaporating the filtrate, and vacuum concentrating to obtain catechin and epicatechin.

6. Application of pericarp of plant of Camellia in preparing catechin and epicatechin is provided.

7. The use according to claim 6, wherein the Camellia plant comprises Camellia oleifera (Camellia oleifera), Camellia kwangtungensis (C.semiseriata), Camellia multidentata (C.polyodonta), Camellia chekiangensis (C.chekianggolia), Camellia nitidissima (C.meiocarpa), Camellia nitidissima (C.nitidis), Camellia nitidissima (C.pingguoensis), Camellia tenuisiana (C.reticulata) and Camellia crassipes (C.crapnelliana).

8. The use of claim 7, wherein the Camellia oleifera comprises Hunan forest series Camellia oleifera, Chang forest series Camellia oleifera, Ganxingo series Camellia oleifera, Ganxing series Camellia oleifera, Ganxiang stone series Camellia oleifera, Cen soft series Camellia oleifera and Sanhua series Camellia oleifera.

Technical Field

The invention belongs to the technical field of food processing, and particularly relates to a method for extracting catechin and epicatechin from camellia plant pericarp.

Background

Camellia (Camellia L.) has about 238 plants in China, the most of which are Yunnan, Guangxi, Guangdong and Sichuan. The camellia plants have high utilization value, and tea (C.sinensis) leaves are the most popular beverage in the world and are important commodities of international trade; the oil tea (C.oleifera) seeds have high oil content, are the main sources of edible oil and industrial oil, crude oil can also be used for medicines, and most camellia plants also have high ornamental value.

The camellia oleifera is a special important oil tree species in China, and the planting area is wide. According to the report, the planting area of the camellia oleifera reaches 6800 million mu in China, the high-yield camellia oleifera forest is 1400 million mu, the yield of camellia oleifera fruits is about 900 million tons, the yield of tea oil is about 63 million tons, and the total yield of the camellia oleifera industry is about 1160 hundred million yuan. According to research, the weight of the oil tea fruit shell accounts for 50% -60% of the fresh weight of the fruit. At present, the mature treatment method is to take oil-tea camellia shells as raw materials to prepare active carbon. However, the processing cost is high, so that the camellia oleifera shells do not enter a resource utilization link but are directly dumped in a camellia oleifera forest, and huge resource waste and environmental protection pressure are caused by the abandonment of a large number of camellia oleifera shells.

Catechin is a kind of phenolic active substance extracted from natural plants such as tea leaves, and mainly comprises 8 monomers of catechin (C), Epicatechin (EC), Gallocatechin (GC), Epigallocatechin (EGC), Catechin Gallate (CG), epicatechin gallate (ECG), gallocatechin gallate (GCG) and epigallocatechin gallate (EGCG). At present, the raw material for industrially extracting catechin is tea.

The tea leaves are subjected to physical processing and sold as beverages, and have the characteristic of high added value, so that the cost of raw materials for extracting catechin is high. The tea polyphenol extracted from tea leaves mainly contains catechin substances, wherein the content of epigallocatechin gallate (EGCG) is the highest and accounts for about 9% of dry substances of the tea leaves; the content of catechin (C) and Epicatechin (EC) is low, and some tea varieties can not be detected even. Therefore, it is difficult to perform a large amount of rapid acquisition by simple extraction and purification.

Currently, the commercial distribution of catechins is mainly Gallocatechin (GC) and Epigallocatechin (EGC) in fact, and not catechins (C) and Epicatechins (EC) in scientific sense. In addition, the process for removing the high-content pigment in the tea polyphenol crude extract is complex, the steps are multiple, and the extraction cost of catechin (C) and Epicatechin (EC) and the subsequent large-scale industrial production are indirectly increased. Currently, there is a strong demand for catechins (C) and Epicatechins (EC) from consumers, but it is difficult to meet the demand of consumers in the market because of high price. Therefore, exploring the high-efficiency extraction path of catechin (C) and Epicatechin (EC) and developing a novel industrial production process become key technical problems with important scientific significance and industrialization value at present.

Disclosure of Invention

The invention aims to provide a novel biological resource (raw material) with low cost and high yield and an extraction method and a process thereof, namely a method for extracting catechin and epicatechin from the peel of a camellia plant, aiming at the defects in the prior extraction technology and resource approach of catechin (C) and Epicatechin (EC).

It is a first object of the present invention to provide a process for extracting catechins and epicatechins, comprising the steps of:

a. collecting pericarp of plant of Camellia, physically crushing, extracting with water and/or ethanol, separating extractive solution, concentrating under reduced pressure, adding ethanol, dispersing, and filtering to obtain filtrate; carrying out rotary evaporation and vacuum concentration on the filtrate, and then carrying out freeze drying to obtain a crude tea polyphenol mixture;

b. dispersing the crude tea polyphenol mixture with ethanol water solution, extracting with mixed solvent of ethyl acetate and n-hexane, collecting organic phase, washing with water and saturated NaCl water solution, drying with anhydrous sodium sulfate, filtering, rotary evaporating the filtrate, and vacuum concentrating to obtain catechin and epicatechin.

Preferably, the water and/or ethanol extraction in step a is multiple times of extraction with water, ethanol or ethanol water solution with any concentration.

More preferably, the ethanol aqueous solution is ethanol aqueous solution with the volume fraction of 95%.

Preferably, the step b specifically comprises: dispersing the crude tea polyphenol mixture with 50% ethanol aqueous solution by volume fraction, extracting with mixed solvent of ethyl acetate and n-hexane at volume ratio of 1:1, collecting organic phase, washing with water and saturated NaCl aqueous solution, drying with anhydrous sodium sulfate, filtering, rotary evaporating the filtrate, and vacuum concentrating to obtain catechin and epicatechin.

Preferably, the step b specifically comprises: dispersing the crude tea polyphenol mixture with 50% ethanol aqueous solution by volume fraction, extracting with mixed solvent of ethyl acetate and n-hexane at volume ratio of 1:1 for 3 times, collecting organic phase, washing with water and saturated NaCl aqueous solution for 1 time respectively, drying with anhydrous sodium sulfate, filtering, rotary evaporating the filtrate, and vacuum concentrating to obtain catechin and epicatechin.

The second purpose of the invention is to provide the application of the camellia plant pericarp in preparing catechin and epicatechin.

The Camellia plants comprise Camellia oleifera (Camellia oleifera), guangning red Camellia (c.semiserirata, also called guangning safflower oil tea and southern Camellia), polydentate red Camellia (c.polyonta), zhejiang red Camellia (c.chekianggoleosa, also called zhejiang safflower oil tea), small fruit oil tea (c.meiocarpa, including liping small fruit oil tea No. 2, liping small fruit oil tea No. 3, etc.), Camellia chrysantha (c.nitidissima), flat fruit Camellia chrysantha (c.pingguoensis), tengchonghua Camellia (c.reticuloliana), red peel brown fruit tea (c.crapnelliana), etc.

The oil tea comprises Hunan forest series oil tea, Chang forest series oil tea, Ganxingle series oil tea, Ganxing series oil tea, Cen soft series oil tea, Sanhua (Huashuo, Huajin, Huaxin) series oil tea, etc.

The peel can be fresh peel, naturally cracked peel or dried peel.

The method can solve the industrial production problems of low content, more impurities, difficult purification, high production cost, difficult pigment removal and the like in the extraction of catechin (C) and Epicatechin (EC) at present, and is suitable for large-scale production; meanwhile, the method of the invention further promotes the resource recycling of the waste oil tea pericarp, and solves the problem of the tea oil production waste.

Drawings

Figure 1 is a hydrogen spectrum of a 1:1 mixture of catechins and epicatechins.

Fig. 2 is a carbon spectrum of a 1:1 mixture of catechins and epicatechins.

Detailed Description

The following examples are further illustrative of the present invention and are not intended to be limiting thereof.

Example 1

a. Selection of raw materials:

the selected oil tea varieties comprise China major oil tea, China golden oil tea, China Xin oil tea, Ganxing No. 48, Ganxing No. 2, Ganxing No. 12, Ganshi No. 83-4, Hunan forest No. 210, Hunan forest No. 69, Cen Soft No. 2, Cen Soft No. 3, Chang forest No. 53, Chang forest No. 4, Chang forest No. 40 and Chang forest No. 3, and other selected camellia plants comprise Guangning red camellia, polydentate red camellia, golden camellia, Pingguo golden camellia, Zhejiang red river red flower oil tea, Tengchong Hua fruit tea, Pinggui small fruit oil tea No. 2 and Li Pingguo small fruit oil tea No. 3; fresh fruits are respectively collected, seeds are removed, and peels are remained.

b. Pretreatment of raw materials:

the peel was rinsed and cut into 0.3mm thick slices.

c. The extraction method comprises the following steps:

and (c) soaking 500g of the peel slices obtained after the treatment in the step (b) in 1000mL of food grade ethanol aqueous solution with the volume fraction of 95%, soaking for 12 hours each time, leaching for 4 times, and then combining leaching liquor. And (4) fully rotating, evaporating and concentrating the leaching liquor in vacuum, adding 100mL of ethanol for dispersion, and filtering to obtain filtrate. Concentrating the filtrate by rotary evaporation under vacuum, and freeze drying at low temperature to obtain crude tea polyphenol mixture containing catechin, epicatechin, catechin glucoside, etc. as main components, wherein the extraction efficiency of the crude tea polyphenol mixture is shown in Table 1.

TABLE 1 statistical table of the efficiency of crude tea polyphenol mixture extracted from each sample

Example 2

Taking 500g of fresh picked cantonese camellia pericarp, cutting, leaching with 1000mL of 95% ethanol water solution with volume fraction for 12 hours each time, leaching for 4 times, combining leaching solutions, then decompressing and concentrating, adding 100mL of ethanol for dispersion, and filtering to obtain filtrate. And (3) performing rotary evaporation and vacuum concentration on the filtrate, and performing low-temperature freeze drying to obtain 15.65g of a crude tea polyphenol mixture with the yield of 3.13%. Further purification analysis found that the crude tea polyphenol mixture contained catechin, epicatechin, catechin glycosides, etc. as the main components.

Dispersing 15.65g of the crude tea polyphenol mixture obtained by extraction with 50% ethanol water solution by volume fraction, and extracting with 100mL of mixed solvent of ethyl acetate and n-hexane at a volume ratio of 1:1 for 3 times. The organic phases were combined and washed 1 time each with distilled water (100mL) and saturated brine (100 mL). The organic phase was dried over anhydrous sodium sulfate and filtered, and the filtrate was further concentrated by rotary evaporation under vacuum to obtain 5.1g (purity about 90%, measured by HPLC analysis) of crude catechin extract containing catechin and epicatechin as main components, wherein the content of catechin: the quantity ratio of epicatechin substances is 1:1, the yield is about 1.02 percent. The crude catechin extract was a 1:1 mixture of catechin and epicatechin, both without further purification.

The specific data are as follows:

the structural formula of catechin (catechin) is shown as formula I:

the structural formula of epicatechin (epicatechin) is shown as formula II:

FIG. 1 is a hydrogen spectrum of a 1:1 mixture of catechin and epicatechin, and FIG. 2 is a hydrogen spectrum of catechin and epicatechinCarbon spectra of epicatechin 1:1 mixtures. Characterization data for catechin and epicatechin 1:1 mixtures:¹H NMR(500MHz,Acetone):δ_H 8.36-7.66(brs,8H),7.07(d,J＝1.8Hz,1H),6.91(d,J＝1.8Hz,1H),6.85(dd,J＝8.2,1.7Hz,1H),6.80(dd,J＝8.1,3.8Hz,2H),6.77(dd,J＝8.1,1.8Hz,1H),6.04(m,1H),5.93(d,J＝2.2Hz,1H),5.89(d,J＝2.2Hz,1H),4.89(s,1H),4.57(d,J＝7.6Hz,1H),4.22(d,J＝4.6Hz,1H),3.98(ddd,J＝22.7,11.7,6.2Hz,2H),3.61(m,1H),2.93(dd,J＝16.1,5.4Hz,1H),2.88(dd,J＝16.6,4.6Hz,1H),2.75(dd,J＝16.6,3.2Hz,1H),2.54(dd,J＝16.0,8.3Hz,1H).¹³C NMR(126MHz,Acetone):δ_C 156.9,156.7,156.7,156.3,156.2,156.0,144.8,144.7,144.5,144.4,131.3,131.3,119.1,118.4,114.8,114.6,114.4,114.3,99.7,98.9,95.3,95.2,94.8,94.5,81.8,78.5,67.4,66.0,28.4,28.1。

example 3

Taking 500g of freshly picked pluridentata peel, cutting, leaching with 1000mL of 95% ethanol water solution with volume fraction for 12 hours each time, leaching for 4 times, combining leaching solutions, then concentrating under reduced pressure, adding 100mL of ethanol for dispersing, and filtering to obtain filtrate. And (3) performing rotary evaporation and vacuum concentration on the filtrate, and performing low-temperature freeze drying to obtain 15.25g of a crude tea polyphenol mixture with the yield of 3.05%. Further purification analysis found that the crude tea polyphenol mixture contained catechin, epicatechin, catechin glycosides, etc. as the main components.

Dispersing 15.25g of the crude tea polyphenol mixture obtained by extraction with 50% ethanol water solution by volume fraction, and extracting with 100mL of mixed solvent of ethyl acetate and n-hexane at a volume ratio of 1:1 for 3 times. The organic phases were combined and washed 1 time each with distilled water (100mL) and saturated brine (100 mL). The organic phase was dried over anhydrous sodium sulfate and filtered, and the filtrate was further concentrated by rotary evaporation under vacuum to obtain 5.0g (purity about 90%, measured by HPLC analysis) of crude catechin extract containing catechin and epicatechin as main components, wherein the content of catechin: the quantity ratio of epicatechin substances is 1:1, the yield is about 1.00 percent. The crude catechin extract was a 1:1 mixture of catechin and epicatechin, both without further purification.

Example 4

The samples of pericarp of other plants of genus Camellia (including Camellia oleifera) referred to in Table 1 of example 1 were also obtained rapidly from catechins and epicatechins by the method of example 2.