Preparation method and application of plant extract

Abstract

The invention belongs to the technical field of plant extraction, and discloses a preparation method of a plant extract, which comprises the following steps: juicing plants at 75-95 DEG C to obtain the plant extract. The preparation method of the plant extract comprises the following steps: step 1, juicing plants at 75-95 DEG C to obtain a solid-liquid mixture; 2, filtering and / or centrifugally separating the solid-liquid mixture to obtain a liquid extract A; and step 3, carrying out microfiltration decoloration treatment on the extract A to obtain the plant extract. According to the method, molecular interaction among chemical molecules is controlled by controlling the temperature in the juicing process, so that the particle size of self-assembled nanoparticles formed by active ingredients in the juicing process is reduced, and the transdermal effect of the plant extract is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of plant extraction, and in particular to a preparation method and application of a plant extract. Background Art

[0002] With the development of skin care products, the concept of plant extracts was born. Plant extracts have become a hot topic in skin care product research due to their advantages of being natural ingredients, generally low irritation and good active ingredient effects. Currently, more and more skin care products containing plant extracts are on the market and are loved by consumers.

[0003] At present, plant extracts are generally obtained by water extraction, alcohol extraction or enzymatic hydrolysis, and some are extracted by simple juicing method. For example, prior art 1: Chinese patent 202110918170.8 discloses purslane extract, skin topical preparation containing it, and preparation method and application thereof. The preparation method of purslane extract comprises the following steps: fresh purslane is juiced, and the juice is collected to obtain purslane extract; no solvent is added during the juicing process, the juicing temperature is 45-55°C, and the juicing time is 5-10min.

[0004] Prior art 1 uses a juicing method to extract the active ingredients from purslane. Its specification states that the main purpose of this technology is to overcome the defects of the prior art in that purslane extracts introduce organic solvents that are irritating to the skin during the preparation process, resulting in a large loss of effective active ingredients and high energy consumption. The technical solution of prior art 1 shows that the juicing method is an efficient method for preparing plant extracts, which can extract a large amount of effective active ingredients and reduce the loss of effective active ingredients.

[0005] However, the active ingredients in most plants have a relatively large molecular weight. According to "The 500 Dalton rule for the skin penetration of chemical compounds and drugs." published by Bos JD and Meinardi MM in "Experimental Dermatology" on June 11, 2000, the molecular weight of the most commonly used drugs in local skin treatment is below 500 Daltons. It is difficult for active ingredients with a molecular weight above 500 Daltons to penetrate the skin and act on the inside of the skin. For example, the main active ingredients of the Centella asiatica extract extracted by conventional extraction methods are asiaticoside and madecassoside, with molecular weights of 959.12 and 975.12 respectively. Therefore, conventional extraction methods such as water extraction, alcohol extraction, enzymatic hydrolysis or conventional juicing methods are difficult to obtain active ingredients that can efficiently penetrate the skin.

[0006] Therefore, the technical problem to be solved by the present invention is: a method for preparing a plant extract is needed to extract active ingredients that can efficiently penetrate the skin. Summary of the invention

[0007] One of the purposes of the present invention is to provide a method for preparing a plant extract. When the plant extract is extracted by the method, self-assembled nanoparticles can be formed to obtain a plant extract with a small particle size and good transdermal effect, thereby effectively improving the transdermal property and skin care effect of the active ingredients.

[0008] Another object of the present invention is to provide a Centella asiatica extract, in which the active ingredients in the Centella asiatica extract have a better effect of penetrating the skin, thereby achieving better soothing, whitening and anti-wrinkle effects.

[0009] At the same time, the present invention also provides a use of the Centella asiatica extract. The Centella asiatica extract obtained based on the present invention has high skin permeability, high soothing, whitening and anti-wrinkle effects, and can be widely used in skin care products for skin beauty.

[0010] To achieve the above object, the present invention provides a method for preparing a plant extract, wherein the plant extract is obtained by squeezing the plant juice at 75-95°C.

[0011] The preparation method of the plant extract of the present invention comprises the following steps:

[0012] Step 1: extracting the plant juice at 75-95°C to obtain a solid-liquid mixture;

[0013] Step 2: filtering and / or centrifuging the solid-liquid mixture to obtain a liquid extract A;

[0014] Step 3: subjecting the extract A to microfiltration and decolorization treatment to obtain the plant extract.

[0015] The present invention can effectively promote the interaction between chemical molecules and form self-assembled nanoparticles by squeezing the plant juice at a specific temperature, and effectively control the particle size of the self-assembled nanoparticles formed by the obtained active ingredients, thereby improving the transdermal effect of the plant extract.

[0016] Preferably, the plants are: olive leaves, green tea leaves, perilla leaves, wormwood leaves, aloe leaves, white willow leaves, birch leaves, witch hazel leaves, arborvitae leaves, plantain leaves, impatiens leaves, rambutan leaves, melaleuca alternifolia leaves, artemisia annua leaves, false anise leaves, eucalyptus leaves, agave leaves, verbena leaves, andrographis paniculata leaves, bamboo leaves, mango leaves, rosemary leaves, loquat leaves, ginseng leaves, stevia leaves, oolong tea leaves, ginkgo leaves, small flower windmill cotyledons, lotus leaves, hydrangea leaves, Alpinia serrulata leaves, lavender leaves, lotus leaves, alpine edelweiss Flowers / leaves, Hypericum perforatum flowers / leaves, Chamomile flowers / leaves, Coffea arabica leaves / seeds, White tomato fruit, Bilberry fruit, Strawberry fruit, Ningxia wolfberry fruit, Avocado fruit, Lemon fruit, Grape fruit, Apple fruit, Grapefruit fruit, Pineapple fruit, Dogwood fruit, Hawthorn fruit, Pomegranate fruit, Milk thistle fruit, Lime fruit, Cherry fruit, Soapberry fruit, Chili pepper fruit, Rosa ciliata fruit, Guava fruit, Tomato fruit, Citrus fruit, Raspberry fruit, Kiwi fruit, Forsythia fruit, Zanthoxylum fruit, Monkey tree breadfruit, Mango, Plum fruit, Longan fruit, Sea fennel whole plant , ginseng root, peony root, lotus root, white water lily root, knotweed root, licorice root, gentian root, carrot root, astragalus root, purple echinacea root, salvia root, Pseudostellaria root, rhodiola root, Polygonum multiflorum root, scutellaria root, Acanthopanax root, Chuanxiong root, elm root, angelica root, rehmannia root, fangfeng root, Panax notoginseng root, Sophora root, Coptis root, turmeric root, Sophora flavescens root, chicory root, Platycodon root, lithospermum root, birch bark, cactus stem, Dendrobium officinale stem, pansy leaf / stem, peony flower, white chamomile flower, saffron, Sophora japonica flower, red One or more fresh plants including: lilies, lotus, white water lily, golden button flower, chrysanthemum, immortelle, lemon flower, rose, trumpet creeper, plum blossom, climbing disk-leaved honeysuckle, jasmine, cherry blossom, saururus, camellia, peony, peach blossom, spring marigold, soap tree flower, sunflower, ylang-ylang, poppy, magnolia, tulip, rose, crape myrtle, lotus seeds / stamens / embryo, whole plant of purslane, whole plant of Centella asiatica, whole plant of Piper melongena, whole plant of orchidaceae, whole plant of shrimp orchid, etc.

[0017] Furthermore, in order to improve the antiseptic effect of the plant extract, the preparation method of the plant extract of the present invention may also include step 4: adding a preservative to the plant extract, and filtering through a security filter to obtain the plant extract containing the antiseptic system.

[0018] More preferably, the preservative is at least one of glycerol, 1,3-butanediol, 1,2-pentanediol, 1,2-hexanediol and betaine.

[0019] Preferably, the juicing time of the juicing process is 20 to 30 minutes.

[0020] Preferably, the filtration in step 2 is 300-1000 mesh gauze filtration or 0.45-0.8 μm filter membrane filtration.

[0021] Preferably, the centrifugal speed of the centrifugal separation in step 2 is 6000-12000 r / min, and the centrifugal time is 10-20 min.

[0022] Furthermore, the centrifugal speed of the centrifugal separation in step 2 is 8000-12000 r / min.

[0023] Furthermore, the centrifugal speed of the centrifugal separation in step 2 is 10000-12000 r / min.

[0024] Further preferably, the centrifugal speed of the centrifugal separation in step 2 is 11000-12000 r / min, and the centrifugal time is 10-15 min.

[0025] More preferably, the step 2 adopts a treatment method combining membrane filtration and centrifugal separation to more fully separate the solids and avoid the problem of excessive impurities in extract A.

[0026] Preferably, the specific operation of step 3 is: putting extract A into a microfiltration membrane filter with a front pressure of 0.15 to 0.22 MPa and a pressure of 2 to 4 m 3 The plant extract is obtained by circulating microfiltration at a flow rate of 1 / h and in a cross-flow manner.

[0027] Further preferably, the microfiltration membrane filter is an Al2O3 ceramic membrane microfiltration machine with a pore size of 0.22um.

[0028] The invention also discloses a Centella asiatica extract, which is extracted by adopting the preparation method of the plant extract.

[0029] The invention also discloses use of the Centella asiatica extract in preparing skin care products.

[0030] Beneficial Effects

[0031] Compared with the prior art, the present invention has at least the following advantages:

[0032] (1) The present invention controls the molecular interaction between chemical molecules by controlling the temperature during the juicing process, thereby reducing the particle size of the self-assembled nanoparticles formed by the active ingredients during the juicing process, thereby improving the transdermal effect of the plant extract;

[0033] (2) The Centella asiatica extract obtained by the method for preparing the plant extract of the present invention can effectively reorganize the high molecular weight active ingredients of Centella asiatica, accelerate the exudation of components such as proteins, flavonoids, terpenes, polysaccharides, etc. in Centella asiatica, and form SAN under the action of non-covalent bonds such as electrostatic attraction, van der Waals force, π-π stacking, hydrogen bonding, etc., to encapsulate insoluble and / or inaccessible molecules such as asiatica glycoside and hydroxy-madecassoside, so that the Centella asiatica extract has a smaller particle size, and has better transdermal and soothing, whitening, and anti-wrinkle effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention is further described below in conjunction with the accompanying drawings and embodiments;

[0035] Figure 1 is an appearance diagram of embodiment 3 of the present invention;

[0036] Figure 2 It is a figure of comparative example 1 of the present invention;

[0037] Figure 3 It is a figure of comparative example 2 of the present invention;

[0038] Figure 4 This is a diagram of the comparative example 3 of the present invention;

[0039] Figure 5 This is the HPLC chart of the Centella asiatica extract of Example 3 of the present invention; DETAILED DESCRIPTION

[0040] The present invention will be further described below in conjunction with the embodiments, but it does not constitute any limitation to the present invention. Any limited number of modifications made within the scope of the claims of the present invention are still within the scope of the claims of the present invention.

[0041] In order to explain the technical content of the present invention in detail, further description is given below in conjunction with the implementation modes.

[0042] Example 1

[0043] A Centella asiatica extract is obtained by extracting using the following steps:

[0044] Step 1: put 100 g of Centella asiatica into a juicer and extract juice at 75° C. for 30 min to obtain a solid-liquid mixture;

[0045] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0046] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3The Centella asiatica extract is obtained by circulating microfiltration at a flow rate of / h and in a cross-flow manner.

[0047] Example 2

[0048] A Centella asiatica extract is obtained by extracting using the following steps:

[0049] Step 1: put 100 g of Centella asiatica into a juicer and extract juice at 95° C. for 25 min to obtain a solid-liquid mixture;

[0050] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0051] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The Centella asiatica extract is obtained by circulating microfiltration at a flow rate of / h and in a cross-flow manner.

[0052] Example 3

[0053] A Centella asiatica extract is obtained by extracting using the following steps:

[0054] Step 1: put 100 g of Centella asiatica into a juicer and extract juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0055] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0056] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The Centella asiatica extract is obtained by circulating microfiltration at a flow rate of / h and in a cross-flow manner.

[0057] Example 4

[0058] A sea fennel extract is obtained by extracting using the following steps:

[0059] Step 1: put 100 g of sea fennel into a juicer and extract the juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0060] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0061] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m3 The sea fennel extract is obtained by circulating microfiltration at a flow rate of 1 / 2 h and in a cross-flow manner.

[0062] Example 5

[0063] A peony flower extract is obtained by extracting using the following steps:

[0064] Step 1: put 100 g of peony flowers into a juicer and extract juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0065] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0066] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The peony flower extract is obtained by circulating microfiltration at a flow rate of 1.5 h and a cross-flow method.

[0067] Example 6

[0068] An olive leaf extract is obtained by extracting using the following steps:

[0069] Step 1: Put 100 g of olive leaves into a juicer and extract juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0070] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0071] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The olive leaf extract was obtained by circulating microfiltration at a flow rate of 1 / h and in a cross-flow manner.

[0072] Example 7

[0073] A green tea leaf extract is obtained by extracting using the following steps:

[0074] Step 1: Put 100 g of green tea leaves into a juicer and squeeze the juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0075] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0076] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The green tea leaf extract is obtained by circulating microfiltration at a flow rate of 1:1 / h and in a cross-flow manner.

[0077] Example 8

[0078] A Platycladus orientalis leaf extract is obtained by extracting using the following steps:

[0079] Step 1: put 100 g of Platycladus orientalis leaves into a juicer and extract juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0080] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0081] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The Platycladus orientalis leaf extract was obtained by circulating microfiltration at a flow rate of 1.5 h and in a cross-flow manner.

[0082] Example 9

[0083] A purslane extract is obtained by extracting using the following steps:

[0084] Step 1: put 100 g of purslane into a juicer and extract the juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0085] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0086] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The purslane extract was obtained by circulating microfiltration at a flow rate of 1 / 2 h and in a cross-flow manner.

[0087] Example 10

[0088] A white tomato extract is obtained by extraction using the following steps:

[0089] Step 1: put 100 g of white tomatoes into a juicer and extract juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0090] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0091] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The white tomato extract was obtained by circulating microfiltration at a flow rate of 1.5 h and a cross-flow method.

[0092] Embodiment 11

[0093] A saffron extract is obtained by extracting using the following steps:

[0094] Step 1: put 100 g of saffron into a juicer and extract the juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0095] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0096] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The saffron extract was obtained by circulating microfiltration at a flow rate of 1.5 h and a cross-flow method.

[0097] Example 12

[0098] An Artemisia annua extract is obtained by extracting using the following steps:

[0099] Step 1: put 100 g of Artemisia annua into a juicer and extract juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0100] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0101] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The Artemisia annua extract was obtained by circulating microfiltration at a flow rate of 1.5 h and in a cross-flow manner.

[0102] Embodiment 13

[0103] A lotus leaf extract is obtained by extracting using the following steps:

[0104] Step 1: Put 100 g lotus leaves into a juicer and extract juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0105] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0106] Step 3: Pour extract A into an Al2O3 ceramic membrane microfiltration machine with a pore size of 0.22um, and perform circulating microfiltration at a front pressure of 0.2Mpa, a flow rate of 3m3 / h, and a cross-flow mode to obtain lotus leaf extract.

[0107] Embodiment 14

[0108] A Herba Lysimachiae extract is obtained by extracting using the following steps:

[0109] Step 1: put 100 g of Shrimp spine orchid into a juicer and extract juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0110] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0111] Step 3: Pour the extract A into an Al2O3 ceramic membrane microfiltration machine with a pore size of 0.22um, and perform circulating microfiltration at a front pressure of 0.2Mpa, a flow rate of 3m3 / h, and a cross-flow method to obtain the shrimp spiny orchid extract.

[0112] Embodiment 15

[0113] A Forsythia suspensa extract is obtained by extracting using the following steps:

[0114] Step 1: put 100 g of Forsythia suspensa into a juicer and extract the juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0115] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0116] Step 3: Pour the extract A into an Al2O3 ceramic membrane microfiltration machine with a pore size of 0.22um, and perform circulating microfiltration at a pressure before the membrane of 0.2Mpa, a flow rate of 3m3 / h, and a cross-flow method to obtain the Forsythia suspensa extract.

[0117] Example 16

[0118] A Radix Pseudostellariae Extract is obtained by extracting using the following steps:

[0119] Step 1: put 100 g of Radix Pseudostellariae Radix into a juicer and extract the juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0120] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0121] Step 3: Pour the extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine and perform cyclic microfiltration at a pressure of 0.2Mpa before the membrane, a flow rate of 3m3 / h, and a cross-flow method to obtain the Pseudostellaria heterophylla extract.

[0122] Comparative Example 1

[0123] A Centella asiatica extract is obtained by extracting using the following steps:

[0124] Step 1: put 100 g of Centella asiatica into a juicer and extract juice at 50° C. for 30 min to obtain a solid-liquid mixture;

[0125] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0126] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The Centella asiatica extract is obtained by circulating microfiltration at a flow rate of / h and in a cross-flow manner.

[0127] Comparative Example 2

[0128] A Centella asiatica extract is obtained by extracting using the following steps:

[0129] Step 1: put 100g of Centella asiatica and 200g of pure water into a juicer and extract the juice at 85°C for 20min to obtain a solid-liquid mixture;

[0130] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0131] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The Centella asiatica extract is obtained by circulating microfiltration at a flow rate of / h and in a cross-flow manner.

[0132] Comparative Example 3

[0133] A Centella asiatica extract is obtained by extracting using the following steps:

[0134] Step 1: Put 100 g of Centella asiatica and 200 g of 50% ethanol solution into a juicer and extract juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0135] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0136] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The Centella asiatica extract is obtained by circulating microfiltration at a flow rate of / h and in a cross-flow manner.

[0137] Comparative Example 4

[0138] A Centella asiatica extract is obtained by extracting using the following steps:

[0139] Step 1: put 100 g of Centella asiatica and 100 g of pure water into a juicer and extract the juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0140] Step 2: Filter the solid-liquid mixture through 300-mesh gauze to obtain a primary filtrate and a filter residue, add 100 g of 50% ethanol solution to the filter residue, put it into a juicer, extract the juice at 85° C. for 20 min, and then filter it through 300-mesh gauze to obtain a secondary filtrate, mix the primary filtrate and the secondary filtrate, and centrifuge it at a speed of 12000 r / min for 12 min to obtain a liquid extract A;

[0141] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The Centella asiatica extract is obtained by circulating microfiltration at a flow rate of / h and in a cross-flow manner.

[0142] Comparative Example 5

[0143] A Centella asiatica extract is obtained by extracting using the following steps:

[0144] Step 1: put 100 g of Centella asiatica and 100 g of pure water into a juicer and extract the juice at 85° C. for 20 min to obtain a solid-liquid mixture;

[0145] Step 2: Filter the solid-liquid mixture through 300-mesh gauze, and then centrifuge it at a speed of 12000 r / min for 12 minutes to obtain a liquid extract A;

[0146] Step 3: Pour extract A into a 0.22um pore size Al2O3 ceramic membrane microfiltration machine with a pressure of 0.2Mpa in front of the membrane and 3m 3 The Centella asiatica extract is obtained by circulating microfiltration at a flow rate of / h and in a cross-flow manner.

[0147] Performance Testing

[0148] 1. Extract particle size analysis

[0149] Test method: The Centella asiatica extracts of Examples 1-3 and Comparative Examples 1-5, the sea fennel extracts of Examples 4-16, the peony flower extract, the olive leaf extract, the green tea leaf extract, the oriental arborvitae leaf extract, the purslane extract, the white tomato extract, the saffron extract, the artemisia annua extract, the lotus leaf extract, the cycad extract, the forsythia extract and the pseudostellaria extract were diluted with pure water to a concentration of 20%, and the average particle size was determined using a Winner 802 nanometer laser particle size analyzer. The specific results are shown in Table 1.

[0150] Table 1 Average particle size of the Centella asiatica extracts obtained from Examples 1-3 and Comparative Examples 1-5

[0151]

[0152]

[0153] According to the results in Table 1, we can see that:

[0154] According to the data of Examples 1-3, the present invention can effectively obtain a Centella asiatica extract with a smaller average particle size by juicing Centella asiatica within a specific temperature range, and the data comparison of Examples 1-3 shows that the average particle size of the Centella asiatica extract obtained by juicing at 85°C will be smaller.

[0155] Similarly, according to the data of Examples 4-12, the technical solution of the present invention for juicing plants within a specific temperature range can be used not only for the extraction of Centella asiatica, but also for the extraction of other plants, such as sea fennel, peony flower, olive leaf, green tea leaf, Platycladus orientalis, purslane, white tomato, saffron, Artemisia annua, lotus leaf, Scutellaria baicalensis, and Forsythia suspensa. The technical solution of the present invention can still be used to obtain plant extracts with a smaller average particle size.

[0156] According to the data comparison of Examples 1-3 and Comparative Example 1, it can be seen that the average particle size of the Centella asiatica extract obtained by juicing at too low a temperature will be greatly increased, indicating that only an appropriate juicing temperature can effectively obtain a Centella asiatica extract with a small average particle size; while an excessively high juicing temperature will seriously affect the activity of the active ingredients in the Centella asiatica extract.

[0157] According to the data comparison of Example 3 and Comparative Examples 2-4, it can be seen that the technical solution of using water and / or ethanol solution for juice extraction and dissolution promotion will seriously affect the formation of self-assembled nanoparticles of active ingredients in Centella asiatica extract, thereby significantly increasing the average particle size of Centella asiatica extract.

[0158] According to the data comparison of Example 3, Comparative Example 2 and Comparative Example 5, it can be seen that the amount of solvent added during the juicing process does not have a significant effect on the average particle size of the Centella asiatica extract, indicating that the increase in the average particle size of the Centella asiatica extract in Comparative Example 2 and Comparative Example 5 is mainly caused by the addition of the solvent itself.

[0159] 2. Microstructure analysis

[0160] Experimental method: The Centella asiatica extracts of Example 3 and Comparative Examples 1-3 were diluted with phosphate buffer to a mass fraction of 100 mg / mL, and then 10 μL of the diluted solution was dropped on a mica sheet and air-dried overnight at 25°C; then the morphology was observed using an atomic force microscope (driving frequency of 70 kHz, elastic modulus of 0.4 N / m, and the probe model was Bruker ScanAsyst-Air). The results are as follows: Figure 1-4 As shown;

[0161] in Figure 1 is a diagram of the appearance of Example 3, Figure 2 This is the appearance diagram of comparative example 1, Figure 3 This is the appearance diagram of comparative example 2. Figure 4 This is a diagram of the appearance of Comparative Example 3; since the solvents used in Comparative Examples 4 and 5 have been used in Comparative Examples 2 and 3, they are no longer illustrated.

[0162] according to Figure 1 and Figure 2-4 From the comparison combined with the data in Table 1, it can be seen that the present invention controls the molecular interaction between chemical molecules by controlling the temperature during the juicing process, so that the particle size of the self-assembled nanoparticles formed by the active ingredients during the juicing process becomes smaller, while too low a temperature and an increase in solvent will significantly affect the formation of the self-assembled nanoparticles of the active ingredients, thereby increasing the particle size of the Centella asiatica extract.

[0163] 3. Determination of asiatica glycoside content

[0164] Referring to the testing agency method (Q / CTI LD-SHPHCD-1230), the Centella asiatica extracts of Examples 1-3 and Comparative Examples 1-5 were tested using the external standard method. The results are shown in Table 2, where the HPLC spectrum of the Centella asiatica extract of Example 3 is shown in Table 2. Figure 5 ;

[0165] Table 2 Results of the content of asiatica in the extracts of Centella asiatica of Examples 1-3 and Comparative Examples 1-5

[0166]

[0167]

[0168] According to the results in Table 2, we can see that:

[0169] According to the data comparison of Examples 1-3 and Comparative Example 1, the use of a specific juicing treatment temperature can significantly improve the extraction efficiency of asiatica glycoside, so that the content of asiatica glycoside in the obtained Centella asiatica extract is greatly increased.

[0170] According to the data comparison between Example 3 and Comparative Examples 2-5, the present invention does not add any solvent during the juicing process, which can effectively ensure that Centella asiatica glycoside will not be lost, thereby greatly improving the extraction efficiency of Centella asiatica glycoside.

[0171] And combined with the results in Table 1, it can be seen that the smaller the average particle size of the Centella asiatica extract obtained, the higher the content of asiatica glycoside extracted. According to the results in Table 1, comparative example 3 has the smallest average particle size of the Centella asiatica extract among comparative examples 1-5, but its asiatica glycoside content is not as good as comparative example 4. It is speculated that the selection, combination and number of juicing treatments of the solvent may also affect the content of asiatica glycoside in the Centella asiatica extract, but compared with the technical solution of the present invention that does not adopt the solvent and directly squeezes the juice within a specific temperature range, the influence is relatively weak.

[0172] 4. Soothing effect test

[0173] Test method: Collect RAW 264.7 cell sediments in the logarithmic growth phase, adjust the cell density to 1×105 cells / mL, add 500 μL of cell suspension to each well of the cell culture plate, and divide the experimental groups into blank group, LPS group, Example 1 group, Example 2 group, Example 3 group, Comparative Example 1 group, Comparative Example 2 group, Comparative Example 3 group, Comparative Example 4 group, Comparative Example 5 group and positive control group. After culturing for 24 hours, carefully remove the supernatant.

[0174] The blank group was added with 500 μL of DMEM solution; the LPS group was added with 500 μL of DMEM solution containing LPS (1 μg / mL); the experimental group (Example 1-3 and Comparative Example 1-5) group: first pre-incubated with 0.1% (w / w) DMEM solution for 2 h, then LPS was added to make the final concentration of 1 μg / mL for co-culture, and the cells were placed in the incubator for continued culture for 24 h; the positive control group was added with 1 mL of DMEM solution containing dexamethasone (50 μg / mL) for pre-incubation for 2 h, then LPS was added to make the final concentration of 1 μg / mL for co-culture, and the cells were placed in the incubator for continued culture for 24 h.

[0175] After 24 hours of co-incubation with drug addition, the supernatant culture fluid of each group was collected, and the relative expression of TNF-α inflammatory factor was calculated by the following formula according to the instructions of the ELISA kit, and the effect of Centella asiatica extract on the release of inflammatory factor TNF-α by cells was detected. The results are shown in Table 3;

[0176] The formula is: relative expression of inflammatory factors = expression of inflammatory factors in the experimental group / expression of inflammatory factors in the blank control group.

[0177] Table 3 Test results of soothing efficacy of Centella asiatica extracts of Examples 1-3 and Comparative Examples 1-5

[0178]

[0179]

[0180] According to the results in Table 3:

[0181] According to the data comparison of Examples 1-3 and Comparative Example 1, the soothing effect of the obtained Centella asiatica extract can be significantly improved by adopting a specific juicing treatment temperature, and the data comparison of Examples 1-3 shows that the soothing effect of the Centella asiatica extract obtained by juicing at 85°C is better. The reason is that the particle size of the self-assembled nanoparticles formed by the active ingredients in the juicing process becomes smaller, thereby improving the transdermal effect of the plant extract.

[0182] According to the data comparison of Examples 1-3 and Comparative Example 1, the soothing effect of the Centella asiatica extract obtained by juicing at too low a temperature will be significantly reduced, indicating that the present invention controls the molecular interaction between chemical molecules by controlling the temperature during juicing, thereby reducing the particle size of the self-assembled nanoparticles formed by the active ingredients during juicing, thereby improving the transdermal effect of the plant extract.

[0183] According to the data comparison of Example 3 and Comparative Examples 2-5, it can be seen that the technical solution of using water and / or ethanol solution to extract juice to promote dissolution will seriously affect the formation of self-assembled nanoparticles of active ingredients in Centella asiatica extract, thereby significantly weakening the soothing effect of Centella asiatica extract.

[0184] 5. In vitro tyrosinase activity assay

[0185] Test method: In a 96-well cell culture plate, 200 μl of DMEM medium containing 10% FBS was used to culture mouse skin melanoma cells B16F10, each well containing 1.5×104 cells, and placed in a CO2 constant temperature incubator (5% CO2, 37°C) for overnight culture. A blank group, a 2μmol / L α-melanocyte stimulating hormone (α-MSH) model group, a positive drug 100μmol / L arbutin treatment group after modeling (positive control group) and different experimental groups after modeling (mass fraction 0.1% Example 1-3 and Comparative Example 1-5); after adding the drug, the culture plate was placed in a CO2 constant temperature incubator (5% CO2, 37°C) and incubated for 48h;

[0186] Take the cell culture medium in the 96-well culture plate, rinse the cells with 1×PBS, and then add 1% Triton X-100 to lyse the cells; collect the cell lysate and centrifuge (4°C, 12000×g, 15min); collect 80μl of the supernatant and transfer it to the 96-well plate, add 20μl of 2mg / ml L-DOPA solution to each well, and incubate in a 37°C metal bath for 1h. Afterwards, use an ELISA reader to detect the absorbance value at 475nm and calculate the relative tyrosinase activity. The results are shown in Table 4.

[0187] Table 4 In vitro tyrosinase activity results of Centella asiatica extracts of Examples 1-3 and Comparative Examples 1-5

[0188] Tyrosinase relative activity Example 1 73 Example 2 79 Example 3 66 Comparative Example 1 124 Comparative Example 2 117 Comparative Example 3 95 Comparative Example 4 91 Comparative Example 5 93 Blank Group 100 Model Group 155 Positive control group 51

[0189] According to the results in Table 4:

[0190] According to the data comparison of Examples 1-3 and Comparative Example 1, the use of a specific juicing treatment temperature can significantly improve the tyrosinase activity inhibition effect of the obtained Centella asiatica extract, and the data comparison of Examples 1-3 shows that the Centella asiatica extract obtained by juicing at 85°C has a better tyrosinase activity inhibition effect. The reason is that the particle size of the self-assembled nanoparticles formed by the active ingredients in the juicing process becomes smaller, thereby improving the transdermal effect of the plant extract.

[0191] According to the data comparison between Examples 1-3 and Comparative Example 1, the tyrosinase activity inhibition effect of the Centella asiatica extract obtained by juicing at too low a temperature will be significantly reduced.

[0192] According to the data comparison between Example 3 and Comparative Examples 2-5, it can be seen that the technical solution of using water and / or ethanol solution for juice extraction and dissolution promotion will seriously affect the formation of self-assembled nanoparticles of active ingredients in Centella asiatica extract, thereby significantly weakening the tyrosinase activity inhibition effect of Centella asiatica extract.

[0193] 6. In vitro detection of type I collagen expression

[0194] Detection method: When the fibroblasts cultured in vitro grow to 80-90% confluence, they are digested with trypsin and inoculated into 96-well plates. After the cells are attached and cultured in the 96-well plates for 48 hours, the fibroblasts are starved overnight using a serum-free starvation medium to synchronize the growth of the cell population, and then grouped into blank groups, positive control groups (10ng / ml TGF-β1), and experimental groups (mass fraction 0.1% of Examples 1-3 and Comparative Examples 1-5). After treating the cells for 48 hours, the cell culture supernatant is taken for ELISA test of type I collagen. The collagen content of the sample group measured is statistically compared with that of the untreated control group to evaluate the effect of the experimental group on the amount of type I collagen produced. The results are shown in Table 5.

[0195] The relative expression of type I collagen = the expression of type I collagen in the experimental group / the expression of type I collagen in the blank control group.

[0196] Table 5 Relative expression of type I collagen in vitro in Centella asiatica extracts of Examples 1-3 and Comparative Examples 1-5

[0197] Relative expression of type I collagen Example 1 1.40 Example 2 1.31 Example 3 1.45 Comparative Example 1 1.08 Comparative Example 2 1.13 Comparative Example 3 1.23 Comparative Example 4 1.26 Comparative Example 5 1.20 Blank Group 1 Positive control group 1.32

[0198] According to the results in Table 5:

[0199] According to the data comparison of Examples 1-3 and Comparative Example 1, it can be seen that the Centella asiatica extract obtained by using a specific juicing treatment temperature has a significant effect on promoting the expression of type I collagen, and the data comparison of Examples 1-3 shows that the Centella asiatica extract obtained by juicing at 85°C has a more significant effect on promoting the expression of type I collagen.

[0200] According to the data comparison of Examples 1-3 and Comparative Example 1, it can be seen that the effect of the Centella asiatica extract obtained by juicing at too low a temperature on promoting the expression of type I collagen will be significantly reduced, indicating that the present invention can effectively improve the effect of the Centella asiatica extract on promoting the expression of type I collagen by controlling the temperature of the juicing process.

[0201] According to the data comparison between Example 3 and Comparative Examples 2-5, it can be seen that the technical solution of using water and / or ethanol solution for juice extraction and dissolution promotion will seriously affect the formation of self-assembled nanoparticles of active ingredients in Centella asiatica extract, thereby significantly weakening the effect of Centella asiatica extract in promoting the expression of type I collagen.

[0202] 7. In vitro transdermal study of Centella asiatica

[0203] Experimental method: After normal human primary epidermal keratinocytes were expanded in vitro, a 3D skin model containing epidermal structure was constructed in a 12-well plate hanging cell culture chamber. Six skin models were constructed for this test, with three parallel samples in each sample group.

[0204] Add 4.4 mL of culture medium to the cell culture wells of a 12-well plate. The cells were suspended together with the cell culture chamber in the cell culture well. 5 μl of the sample was evenly applied on the surface of the 3D skin. The culture medium in the lower chamber of the cell culture well was collected at 8 h and 24 h, 1000 μL each time, and then supplemented with an equal volume of culture medium. The content of Centella asiatica was quantitatively detected by HPLC external standard method according to the manufacturer's guidance documents, and each group of quantitative samples had 3 parallel samples.

[0205]

[0206] The Centella asiatica extracts of Examples 1-3 and Comparative Examples 1-5 were tested according to the above experimental method, and the results are shown in Table 6;

[0207] Table 6 Cumulative skin penetration rate of Examples 1-3 and Comparative Examples 1-5

[0208]

[0209] According to the results in Table 6 combined with the data in Table 1, we can know that:

[0210] According to the data comparison of Examples 1-3 and Comparative Example 1, the present invention controls the molecular interaction between chemical molecules by controlling the temperature during the juicing process, so that the particle size of the self-assembled nanoparticles formed by the active ingredients during the juicing process becomes smaller, thereby improving the transdermal effect of the plant extract.

[0211] And according to the data comparison of Example 3 and Comparative Examples 2-5, it can be seen that the technical solution of using water and / or ethanol solution to extract juice and promote dissolution will seriously affect the formation of self-assembled nanoparticles of active ingredients in Centella asiatica extract, thereby affecting the average particle size of Centella asiatica extract, and further affecting the transdermal effect of Centella asiatica glycoside, thereby affecting the skin care effect of Centella asiatica glycoside.

[0212] The embodiments presented herein are only embodiments selected according to the combination of all possible embodiments. The appended claims should not be limited by the embodiments describing the present invention. Some numerical ranges used in the claims include sub-ranges therein, and the changes in these ranges should also be covered by the appended claims.

Claims

1. A method for preparing a plant extract, characterized in that: The plant extract is obtained by squeezing the plant juice at 75-95°C.

2. The method for preparing the plant extract according to claim 1, characterized in that: The steps include: Step 1: extracting the plant juice at 75-95°C to obtain a solid-liquid mixture; Step 2: filtering and / or centrifuging the solid-liquid mixture to obtain a liquid extract A; Step 3: subjecting the extract A to microfiltration and decolorization treatment to obtain the plant extract.

3. The method for preparing the plant extract according to claim 2, characterized in that: The method also includes step 4: adding a preservative to the plant extract, and filtering the plant extract through a security filter to obtain the plant extract containing the preservative system.

4. The method for preparing the plant extract according to claim 3, characterized in that: The preservative is at least one of glycerol, 1,3-butylene glycol, 1,2-pentanediol, 1,2-hexanediol and betaine.

5. The method for preparing a plant extract according to claim 1 or 2, characterized in that: The juicing time of the juicing process is 20 to 30 minutes.

6. The method for preparing the plant extract according to claim 2, characterized in that: The filtration in step 2 is 300-1000 mesh gauze filtration or 0.45-0.8 μm filter membrane filtration.

7. The method for preparing the plant extract according to claim 2, characterized in that: The centrifugal speed of the centrifugal separation in step 2 is 6000-12000 r / min, and the centrifugal time is 10-20 min.

8. The method for preparing the plant extract according to claim 2, characterized in that: The specific operation of step 3 is: put extract A into a microfiltration membrane filter with a pressure of 0.15-0.22 MPa before the membrane and 2-4 m 3 The plant extract is obtained by circulating microfiltration at a flow rate of 1 / h and in a cross-flow manner.

9. A plant extract, characterized in that The extract is obtained by extraction using the preparation method of the plant extract as described in any one of claims 1 to 8.

10. Use of the plant extract according to claim 9 for preparing skin care products.

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