KR102279336B1 - Cosmetic composition for comprising sweet potato extract - Google Patents

Abstract

The present invention basically contains a sweet potato tuber root ethanol extract, and further includes a sweet potato pure ethanol extract and a pure vegetable leaf ethanol extract, which have a synergistic effect on the sweet potato tuber root ethanol extract, to moisturize the skin, whiten the skin, maintain or improve skin elasticity , is a cosmetic composition that is very effective in preventing skin wrinkles, and ultimately can be usefully used for skin anti-aging effects.

Description

Cosmetic composition comprising sweet potato extract as an active ingredient

The present invention relates to a cosmetic composition comprising a sweet potato extract as an active ingredient, and more particularly, to a new cosmetic composition in which the effect of the containing cosmetic composition is significantly increased through the synergistic effect of the pure sweet potato extract to the sweet potato tuber root extract. will be.

Sweet potato is a dicotyledonous plant, a perennial herb of the Convolvulaceae family, and is also called Gamseo and Sweet potato. It is widely cultivated throughout Korea. It is about 3 m long. Stems extend along the ground for a long time and take root. The leaves are alternate phyllotaxis, the leaf body is shallowly split in the shape of a heart, and the juice is released when the leaves and stems are cut. It takes root at the base of the petiole at the bottom of the stem, and a part of it grows in the ground to become a tuber, a sweet potato. Its shape varies from cylindrical to spherical with pointed sides, and its color varies from white, yellow, light red, red, and light purple.

The flowers are hung on the peduncle from the leaf axil in July-August in the shape of light red morning glory. The calyx is divided into 5 pieces. Corolla is funnel-shaped and has 5 stamens and 1 pistil. The fruit is a ball-shaped capsule, with 2 to 4 blackish brown seeds ripening. When frost falls in the fall, the leaves and stems wither. At this time, the sweet potatoes are digged and stored for thermal insulation, and then sprouted when planted in the seedling in the spring of the following year. If you cut a shoot and plant it in the field, it will take root. In the subtropics and tropics, it does not wither all year round, so cut the stems at an appropriate time to reproduce. Seeds are not used for cultivation.

The origin of the sweet potato is estimated to be from Mexico to northern South America, and the original species is not clearly identified. It is generally assumed that it was cultivated in Central and South America about 2000 years ago. At the time of the discovery of the new continent, it was widely cultivated by indigenous peoples, and it was brought to Spain by Christopher Columbus, then to the Philippines and Fujian Province of China, and then spread to other Asian countries. It is mainly cultivated in Asia and Africa, and production is low in the West. As a country, it is widely cultivated in China, Indonesia, Korea, and Brazil, and there are many varieties around the world. There are various varieties according to appearance and taste, growth rate, inner color such as white, yellow, red, purple, etc., viscosity, etc. For industrial use, it is good to have a high starch content and a high yield, and for feed, select one that can harvest both sweet potatoes and vines. In Korea, varieties such as Chungseung No. 100, Suwon No. 147, Shinmi, and Hwangmi are grown.

Sweet potato contains 69.39% water, 27.7% sugar, 1.3% protein, and the main component is starch. Before World War II, it was mostly consumed for food, but recently, it is only used as a side dish or snack, not as a food supplement as in the past, as only about 40% of the food is eaten. For industrial purposes, about 30% is used for starch, and it is widely used as a raw material for syrup, glucose, confectionery, edible processed products, pharmaceuticals, cosmetics, ethanol, whiskey, and soju. It is also used as feed for livestock such as pigs, and leaves and stems are used as green manure to maintain the productivity of the land.

Such a cosmetic use example of sweet potato relates to cosmetics for atopic dermatitis containing purple sweet potato extract, and more specifically, to Stephirococcus aureus, which is the causative agent of atopy, contains triclosan and purple sweet potato together to show a synergistic effect. Korean Patent Publication No. 10-2011-0131855, which discloses cosmetics for atopic dermatitis using this, and Ginkgo biloba extract, Mage extract, purple sweet potato extract, Seonhakcho extract, cacao extract, King elm bark extract, and fermented red ginseng extract in a certain mixing ratio. There is Korean Patent No. 10-1931549, which discloses a cosmetic composition having a skin protection and whitening effect in a mixed composition.

However, they only use the tuberous root part of the sweet potato as a cosmetic ingredient, and the scope of its use is also limited. There are no proposals on how to enhance the effectiveness of the tuber root extract of sweet potato.

1. Korean Patent Publication No. 10-2011-0131855 2. Korean Patent No. 10-1931549

Therefore, the technical problem to be achieved by the present invention is to further expand the effective range of the sweet potato tuber root extract and also use other extracts that can have a synergistic effect on the sweet potato tuber root, for example, the effect of a sweet potato extract-containing cosmetic composition using a sweet potato net extract. It is to provide a new cosmetic composition that significantly increased.

In order to achieve the above technical object, the present invention is to heat the extract obtained by extracting the mixture with ethanol after mixing the tuber root of sweet potato, the dried sweet potato purely, and the dried pure green leaves in the same weight ratio, respectively, after evaporating the ethanol. After dissolving the residue in purified water, 1 × 10 ⁷ cell/ml yeast (Isakenchia orientalis) was inoculated at 1 part by weight based on 100 parts by weight of the total extract, and then fermented at 30° C. for 24 to 96 hours. There is provided a cosmetic composition for skin whitening containing the filtered fermented product as an active ingredient.

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The present invention basically contains a sweet potato tuber root ethanol extract, and further includes a sweet potato pure ethanol extract and a pure vegetable leaf ethanol extract, which have a synergistic effect on the sweet potato tuber root ethanol extract, to moisturize the skin, whiten the skin, maintain or improve skin elasticity , is a cosmetic composition that is very effective in preventing skin wrinkles, and ultimately can be usefully used for skin anti-aging effects.

Hereinafter, specific contents for carrying out the present invention will be described.

The cosmetic composition according to the present invention basically contains an ethanol extract from a sweet potato tuber as it exhibits skin moisturizing, skin whitening, skin elasticity maintenance or improvement, skin wrinkle prevention effect, and ultimately skin anti-aging effect.

The sweet potato used in the present invention is not particularly limited in its variety, and the extraction method using ethanol is also widely known in the art to which the present invention pertains.

In addition, in the present invention, a sweet potato net ethanol extract may be further included in order to increase the effect of the sweet potato tuber root extract, and the sweet potato sprouts are also not limited to a specific variety, and the harvest period is also not limited.

As described above, the sweet potato tuber root ethanol extract and sweet potato pure ethanol extract each preferably contain 0.001 to 20% by weight based on the total weight of the composition, and when it is less than that, an effect can be exhibited, and when it is contained in excess, the effect is further There is no increase, and it is undesirable because it may affect the stability of the formulation.

The composition according to the present invention may further include an ethanol extract of pure vegetable leaves in order to further enhance the effect of the sweet potato extract, and preferably, the composition according to the present invention contains 0.001 to 20% by weight of the ethanol extract of pure vegetables based on the total weight of the composition. will be.

Perennial herbs are perennial plants of the dicotyledonous plant, Buttercylaceae, and its scientific name is Brasenia. schreberi , which grows in ponds, but was also cultivated in paddy fields to eat leaves and shoots in the past. The leaves are alternate phyllotaxis and oval, the back side is purple, and the petiole hangs in the center. When the leaves grow, they are surrounded by agar-like mucus along with the young stems. Flowers bloom from May to August, are black, reddish purple, and hang one by one at the end of a long peduncle that grows from the leaf axil, and is about 2cm in diameter. There are three sepals and three petals each. There are 6-18 pistils, there are nipple-shaped projections, and there are many stamens. The stamen surrounds the pistil and is longer than the pistil, and the central pistil is curved outward. After the operation withers, the pistil grows and a sticky slime is formed on the head.

In addition, the ethanol extract for the sweet potato tuber root, sweet potato sprout, and pure vegetable leaf can be fermented by inoculating yeast. After concentration and drying, it is used after dissolving in water. In addition, preferably, the ethanol extract is used after sterilization for 0.5 to 24 hours, preferably 1 to 6 hours at 80 ~ 105 ℃, preferably 90 ~ 100 ℃ in order to suppress the propagation of various bacteria.

The strain to be inoculated for fermentation of the extract in the present invention is yeast, preferably Issatchenkia orientalis ) yeast. The inoculation amount of yeast is 0.001 to 10 parts by weight, preferably 0.01 to 5 parts by weight, based on 1 × 10 ⁷ cell/ml yeast solution, based on 100 parts by weight of ethanol extract for sweet potato tubers, sweet potato shoots, and pure green leaves. Preferably 0.1 to 3 parts by weight is used.

After inoculating the yeast with the extract, it is fermented at 25 to 40 ℃, preferably 30 to 35 ℃ for 18 to 78 hours, preferably for 48 to 72 hours, such fermentation is sub-moisturizing, skin whitening, maintaining skin elasticity. improvement, brings a significant increase in skin anti-wrinkle effect.

As described above, the cosmetic composition in the present invention may include components commonly used in cosmetic compositions, for example, conventional adjuvants such as antioxidants, stabilizers, solubilizers, vitamins, pigments and fragrances, and carriers. include

Such a cosmetic composition may be prepared in any formulation conventionally prepared in the art. In one embodiment, it may be any one formulation selected from the group consisting of a high-viscosity emulsifier type, a low-viscosity emulsifier type and a solubilizing formulation, but is not limited thereto. According to the formulation to be manufactured, it may include a cosmetic composition formulation component commonly used in the technical field to which the invention pertains. For example, to be formulated as a solution, suspension, emulsion, paste, gel, cream, lotion, powder, soap, surfactant-containing cleansing, oil, powder foundation, emulsion foundation, wax foundation, pack, massage cream, and spray. However, the present invention is not limited thereto. More specifically, flexible lotion, nourishing lotion, nourishing cream, massage cream, essence, eye cream, sun lotion, sun cream, makeup base, BB cream, cleansing cream, cleansing foam, cleansing water, pack, stick product, balm ( Balm) type product, spray or powder formulation.

Depending on the formulation to be manufactured, an aqueous phase component, an oil phase component, a surfactant, a moisturizer, a lower alcohol, a thickener, a chelating agent, a preservative, a fragrance, etc. may be selected and added.

Hereinafter, the present invention will be described in detail through Examples and Experimental Examples. It is clear that the present invention is not limited by the description of the above-described embodiments.

<Example 1: Preparation of a composition according to the present invention>

After grinding the tuber roots of yellow sweet potato produced in Taean, 500 g of the crushed tuber roots were mixed with 1 liter of ethanol.

The mixed raw materials were immersed and extracted for 7 days at room temperature, and then filtered with a 250 mesh and 0.5 μm filter paper to obtain a liquid extract. The obtained liquid extract was concentrated to prepare a composition according to the present invention.

<Example 2: Preparation of a composition according to the present invention>

In the same manner as in Example 1, the seeds of yellow sweet potato produced in Taean were dried and then pulverized, and 500 g of the pulverized product was further included to prepare a composition according to the present invention.

< Example 3: Preparation of the composition according to the present invention>

A composition according to the present invention was prepared in the same manner as in Example 2, except that 500 g of pulverized dried pure vegetable leaves were further included.

< Example 4: Preparation of the composition according to the present invention>

Same as in Example 3, except that after evaporating the ethanol by heating the extract, the residue is dissolved in purified water, and then 1 × 10 ⁷ cell/ml yeast (Isakenchia orientalis) is added to 100 parts by weight of the total extract by weight. After inoculation with the parent, the composition according to the present invention was prepared by fermenting at 30° C. for 24 to 96 hours and then filtering.

< comparative example 1: Preparation of pure sweet potato pure ethanol extract>

It is the same as in Example 1, but there is a difference in ethanol extraction using only sweet potato shoots.

< comparative example 2: Preparation of pure vegetable alone ethanol extract>

It is the same as in Example 1, but there is a difference in ethanol extraction using only pure vegetables.

< test example 1: Moisturize the skin>

1. Cytotoxicity experiments

The cytotoxicity test was performed by Moseman's method (Moseman TJ, Immuno Methods, 65, 55 (1983)) and Skaper et al. (Skaper SD, et al, Cell Culture, 2, 17 (1990)) using MTT (3-4). ,5-dimethylthiazol-2yl)-2,5-diphenyl-2H-tetrazolium bromide) was measured.

Human keratinocytes HaCaT were purchased from the Korean Cell Line Bank (Seoul, Korea) and used. HaCaT was cultured in an animal cell incubator at 37°C and 5% CO2 supply condition in a laboratory using DMEM medium containing antibiotics of 10% (V/V) FBS, penicillin 100U/mL, and streptomycin 100g/mL.

The compositions of Examples and Comparative Examples were dissolved in DMSO and added to the culture medium at 100 g/mL, and the cells were cultured in the culture medium for 24 hours. After treatment with MTT solution (5 mg/mL) and further incubated for 4 hours, the amount of the produced blue crystal formazan was measured for absorbance at 595 nm using an ELISA reader. Toxicity to cells was expressed as a percentage of the average absorbance value of each control group.

To investigate cytotoxicity in HaCaT keratinocytes, when treated at a concentration of 100 g/mL, cytotoxicity was investigated by calculating the degree of change in cell proliferation compared to that treated only with DMSO, a control.

In all the results, cell viability showed a result of 95 to 98%, and it was found that both the compositions of Examples and Comparative Examples had no cytotoxicity.

2. Moisture when applied to the human body possessive evaluation

In order to evaluate the skin moisturizing effect of the compositions of Examples and Comparative Examples, the moisture retention ability was measured as follows for skin coated with each test substance of Examples and Comparative Examples. The test substance dissolved in purified water at 15% by weight was used.

Moisture retention capacity was measured by applying a certain amount (0.1g/4cm2) to the inside of the forearms of 20 subjects in a constant temperature and humidity room with a room temperature of 22°C and a relative humidity of 45%, and the skin before, 1 hour after, and 2 hours after application. of the water content was measured. As the measuring device, a moisture content meter (corneometer CM820, Courage + Khazaka, Cologne, Germany) that measures the moisturizing power by measuring the electric capacity of the skin according to the moisture content of the skin was used, and the results are shown in Table 1 below.

electrical conductivity before application 1 hour after application 2 hours after application Example 1 50 83 77 Example 2 50 85 80 Example 3 50 88 83 Example 4 50 90 85 Comparative Example 1 50 56 51 Comparative Example 2 50 56 51

From Table 1, it was confirmed that the composition according to the present invention has significantly superior water retention ability compared to the composition of Comparative Example, which proves that it is a material having a very excellent moisturizing effect. The excellent effect in Examples 2 and 3 is due to the synergistic effect on the sweet potato sprouts and pure vegetable leaf extracts, and in particular, the synergistic effect by fermentation can be confirmed from the results of Example 4.

3. Aquaporin -3 and Involuclein Synthesis accelerating effect experiment

In order to confirm the effect of increasing the synthesis of involucrin, which plays an important role in the barrier and moisturizing functions of skin cells, and aquaporin-3, which plays an important role in water movement, the compositions of Examples and Comparative Examples were applied to the cells as follows. After each treatment, it was confirmed by western blotting.

First, human keratinocytes were inoculated with HaCaT, and after 24 hours, the compositions of Examples and Comparative Examples were added, respectively, and cultured in DMEM medium, 37° C., 5% CO 2 . After culturing for 24 hours, the cells were recovered, disrupted, and only proteins were extracted and stored at -40°C. The extracted protein was quantified by BCA saasy. After dilution with 30 g of protein in each sample, electrophoresis on 12% SDS-gel was carried out, and the resultant was transferred to PVDF membrane. After reacting with the primary antibody (rabbit anti-aquaporins-3 antibody), the remaining antibody was washed and removed and reacted with the secondary antibody (rabbit HRP-coupled anti-IgG antibody).

After removing the remaining antibody, a reagent (peroxidase substrate and chromogen solution) that reacts with the antibody to cause a color reaction was added. The colored band was measured and quantified through image analysis (BioRad, Universal Hood, USA), and the results are shown in Tables 2 and 3 below.

division Aquaporin-3 expression level (%) control 100 Example 1 148 Example 2 153 Example 3 157 Example 4 163 Comparative Example 1 105 Comparative Example 2 103

As shown in Table 2, Comparative Examples 1 and 2 showed little effect compared to the control group, and Examples 1 to 4 according to the present invention showed an effect of 50% or more, and a synergistic effect in Examples 2 and 3. In particular, a remarkable synergistic effect was confirmed in Example 4.

division Expression level of involucrin (%) control 100 Example 1 149 Example 2 153 Example 3 155 Example 4 164 Comparative Example 1 102 Comparative Example 2 101

As shown in Table 2 above, Comparative Examples 1 and 2 showed little effect compared to the control group on the expression of involucrin, which plays an important role in skin barrier function and moisturizing, when treated with HaCaT keratinocytes. Examples 1 to 4 showed an effect of 50% or more, and a synergistic effect in Examples 2 and 3. In particular, a remarkable synergistic effect was confirmed in Example 4.

Through the above experimental results, the composition of the present invention was able to confirm the excellent effect on the skin barrier function and moisturizing.

< test example 2: skin mimeek >

1. Confirmation of melanin production inhibitory effect

The compositions of Examples and Comparative Examples were added to the culture medium of B-16 mouse melanoma cells to test the whitening effect at the cellular level. (Lotan R, Lotan D Cancer Res 40:3345-3350, 1980)

Before the experiment, toxicity was evaluated for melanoma cells in mice, and a non-toxic concentration was selected for whitening evaluation.

The final concentration was tested to be 100㎍/ml, and arbutin, a control, was added to the medium so that it became 100㎍/ml, treated with B-16 melanoma cells, respectively, and cultured for 3 days.

Thereafter, the cells were treated with trypsin, removed from the culture vessel, centrifuged, and then melanin was extracted. To the detached cells, 1 ml of sodium hydroxide solution (1N concentration) was added and boiled for 10 minutes to dissolve melanin. Using a spectrophotometer, absorbance was measured at 400 nanometers (nm) to measure the amount of melanin produced.

The amount of melanin was measured by a method indicated by the absorbance per unit cell number (10 ⁶ cells), the relative melanin production to the control was calculated as the inhibition rate (%), and the results are summarized in Table 4. Also, the experiment was repeated 3 times.

sample melanin production Inhibition rate (%) negative control 0.065±0.002 - positive control 0.033±0.001 49% Example 1 0.015±0.003 77% Example 2 0.012±0.001 81% Example 3 0.010±0.001 85% Example 4 0.007±0.003 89% Comparative Example 1 0.059±0.001 10% Comparative Example 2 0.059±0.001 10%

As can be seen from the results in Table 4, it was found that the composition of the present invention has a significantly superior melanogenesis inhibitory ability against cultured mice melanoma cells when compared with arbutin, a known whitening material, Comparative Examples 1 and 2 showed an insignificant effect of about 10% compared to the negative control, thereby remarkably revealing the superiority of the composition according to the present invention. effect could be confirmed.

< test example 3: Prevents skin wrinkles and maintains elasticity>

One. Elastase Inhibition rate measurement

The inhibitory effect of Elastase, an enzyme decomposing elastin, was confirmed as follows.

Elastase used elastase derived from human leukocyte cells, and a synthetic substrate MeOSuc-Ala-Ala-Pro-Val-pNA was used as a substrate for elastase. A buffer solution of 100 mM Tris (pH 7.5) was used. Elastase was finally used at 0.2 mU using a buffer solution. In addition, the synthetic substrate of elastase was diluted with a buffer solution so that a final concentration of 05 mM after making a 100 mM solution using DMSO.

At this time, the positive control was set to put quercetin (Quercetin) known as an elastase inhibitor at a concentration of 100ppm. Samples of Examples and Comparative Examples were also added so as to be 100 ppm. The reaction was carried out in a 96-well plate, and the reaction was carried out at room temperature for 20 minutes. The absorbance was measured at 405 nm at 1-minute intervals using a spectrophotometer, and the slope of the absorbance versus time was determined to determine the activity of the enzyme. The elastase inhibition rate was calculated as follows and the results are shown in Table 5.

sample Elastase inhibition rate (%) positive control 43.12% Example 1 77.29% Example 2 82.34% Example 3 85.21% Example 4 88.21% Comparative Example 1 42.18% Comparative Example 2 42.36%

As can be seen from the results in Table 5, it was found that the composition of the present invention had a very good elastase inhibitory ability, and although it showed some effect in Comparative Examples 1 and 2, it was more insignificant than in Example 1, Examples 2 and 3 included in Example 1 showed remarkably superiority, which confirmed the synergistic effect of the pure sweet potato extract on the tuber root of the sweet potato, the synergistic effect of the pure vegetable extract, especially the remarkable synergistic effect by fermentation.

2. Collagenase Inhibition rate measurement

The inhibitory effect on the activity of collagenase, an enzyme that decomposes collagen, was confirmed as follows.

Collagenase derived from mouse pancreas was used, and a synthetic substrate N-(3-[2-Furyl]acryloyl)-Leu-Gly-Pro-Ala was used as a substrate for collagenase. A buffer solution in which 50 mM Tricine, 10 mM CaCl ₂ ·H ₂ O, and 400 mM NaCl (pH7.5) were dissolved was used. The synthetic substrate was dissolved at a concentration of 10 mM using a buffer and finally diluted to 75 μM. Collagenase was dissolved in 4 degree cold tertiary distilled water to a concentration of 1 unit/ml and finally diluted with a buffer solution to 0.05 unit/ml.

The samples of Examples and Comparative Examples were tested at a final concentration of 100 ppm. At this time, the positive control group was set to have a final concentration of 100 ppm of epigallocatechin gallate (EGCG), which is known to have a collagenase inhibitory effect. The reaction was carried out in a 96-well plate, and reacted at room temperature for 10 minutes. The absorbance was measured at 345 nm at intervals of 1 minute using a spectrophotometer, and the maximum slope of the absorbance versus time was obtained and determined as the activity of the enzyme. The collagenase inhibition rate was calculated as follows and the results are shown in Table 6.

sample Collagenase inhibition rate (%) positive control 42.12% Example 1 68.18% Example 2 71.25% Example 3 75.28% Example 4 80.12% Comparative Example 1 39.15% Comparative Example 2 39.18%

As can be seen from the results in Table 6, it was found that the composition of the present invention had a very excellent collagenase inhibitory ability, and although it showed some effect in Comparative Examples 1 and 2, it was more insignificant than that of Example 1, Examples 2 and 3 included in Example 1 showed remarkable superiority, which demonstrates the synergistic effect of the pure sweet potato extract on the tuber root of the sweet potato, the synergistic effect of the pure vegetable extract, in particular, the remarkable synergistic effect by fermentation.

3. Measurement of cell proliferation effect

In order to confirm the activation of skin cell proliferation, cell proliferation activity was measured using human fibroblasts.

After adding the compositions of Examples and Comparative Examples at 10 μg/ml to the culture medium, the MTT reduction method was performed by culturing human fibroblasts, and the formazan product was extracted with isopropyl ethanol, and absorbance was measured at 570 nm. By doing so, the cell proliferation activity was compared. At this time, as a negative control, a culture medium without the sample was used. The measured results were numerically calculated using the following formula, and the results are shown in Table 7 below.

Cell proliferative capacity (%) = absorbance in each sample group / absorbance in control group

sample Cell proliferative activity (%) Example 1 137.28% Example 2 139.18% Example 3 142.28% Example 4 144.14% Comparative Example 1 112.15% Comparative Example 2 115.18%

As can be seen from the results of Table 7, the composition of the present invention showed a very excellent cell proliferation activity compared to the cell proliferation activity (100%) of the untreated control group, and also showed some effect in Comparative Examples 1 and 2. I was more insignificant than in Example 1, and the superiority was remarkably shown in Examples 2 and 3, which were included in Example 1, which was the synergistic effect of the sweet potato net extract on the tuber root of the sweet potato, the synergistic effect of the pure vegetable extract, especially the fermentation. This proves a significant synergistic effect by

As a result of the above examination, it was found that the cosmetic composition according to the present invention is excellent in maintaining and improving skin elasticity and preventing skin wrinkles, and is ultimately the best cosmetic composition capable of preventing skin aging.

In summary of the above-described test examples, the composition according to the present invention has remarkably excellent advantages in skin moisturizing, skin whitening, maintaining or improving skin elasticity, skin wrinkle prevention effect, and ultimately skin anti-aging effect.

Claims (4)

After mixing the pulverized tuber root of sweet potato, pulverized dry sweet potato, and dried leaf by weight in the same weight ratio, the mixture was extracted with ethanol by heating the extract to evaporate the ethanol, and then the residue was dissolved in purified water and then 1 × 10 ⁷ cell/ml yeast (Isakenchia orientalis) was inoculated at 1 part by weight based on 100 parts by weight of the entire extract, and then fermented at 30° C. for 24 to 96 hours and then filtered fermented product containing as an active ingredient A cosmetic composition for skin whitening.



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