• Title/Summary/Keyword: Electron concentration

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The Anti-Oxidant Effect of Extracts from the Vaccinium oldhami (정금나무(Vaccinium oldhami) 열매의 항산화 효과)

  • Chae, Jung-Woo;Kong, Hye-Jin;Lee, Mi-Ji;Park, Jung-Yeon;Kim, Ji-Hyang;Kim, Young-Hun;Lee, Chang-Eon;Kim, Kyung-Hwan
    • Journal of Life Science
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    • v.20 no.8
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    • pp.1235-1240
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    • 2010
  • Natural compounds have been studied to substitute synthetic antioxidants. In this study, the anti-oxidant activity of 70% acetone extracts from the Vaccinium oldhami fruit was investigated for utilization as ingredients for the cosmetic and bio-industries. Anti-oxidant activity was determined by determining total polyphenolic content, electron donating ability, nitric oxide (NO) radical scavenging activity, $ABTS{\cdot}^+$ cation radical scavenging activity and hydrogen peroxide scavenging activity. The polyphenolic content of 70% acetone extracts of the Vaccinium oldhami fruit was 55.972 mg TAE/g. In electron donating activity, 70% acetone extracts of the Vaccinium oldhami fruit showed an effect of 93.9%, which was similar to BHA effect at a concentration of 500 ${\mu}g/ml$. In the NO radical scavenging ability, 70% acetone extracts of the Vaccinium oldhami fruit showed 60% at 500 ${\mu}g/ml$. $ABTS{\cdot}^+$ cation radical scavenging activity of the Vaccinium oldhami fruit at a concentration of 1000 ${\mu}g/ml$ was 75.7%. Also, hydrogen peroxide scavenging activity of 70% acetone extracts showed 80.8% at 100 ${\mu}g/ml$, whichwas higher than BHA. In the natural compound market, the most important factors are the ability to obtain high effects of a material in low concentrations and a long-lasting supply. The Vaccinium oldhami fruit can be harvested every year - this fulfills one of the requirements. From these results, we can confirm that the Vaccinium oldhami fruit has anti-oxidant abilities and has potential as a natural anti-oxidant agent to be utilized in the cosmeceutical and bio-industries.

MECHANISM IN ANTIBACTERIAL ACTIVITY OF POLYPHOSPHATES AGAINST PORPHYROMONAS ENDODONTALIS (Porphyromonas endodontalis에 대한 Polyphosphate의 항균기전에 관한 연구)

  • Choi, Sung-Baik;Park, Sang-Jin;Choi, Gi-Woon;Choi, Ho-Young
    • Restorative Dentistry and Endodontics
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    • v.25 no.4
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    • pp.561-574
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    • 2000
  • Poly-P has been used to prevent decomposition of foods and has been shown to have inhibitory effect on the growth of gram positive bacteria. The purpose of this study was to evaluate the effect of poly-P on the growth of Porphyromonas endodontalis, a gram negative obligate anaerobic rod, endodontopathic bacterium. P. endodontalis ATCC 35406 was in BHI broth containing hemin and vitamin K with or without poly-P. Inhibitory effect of each poly-P which was added at the beginning(lag phase) or during(exponential phase) the culture, MIC(minimum inhibitory concentration) was determined by measuring the optical density of the bacterial cell at 540nm. Viable cell counts were measured to determined whether poly-P has a bactericidal effect. Leakage of intracellular nucleotides from P. endodontalis was determined at 260nm and morphological change of P. endodontalis was observed under the TEM(transmission electron microscope). Binding of 32P-labeled poly-P to P. endodontalis was examined. SDS-polyacrylamide gel electrophoresis and zymography were performed to observe the changes in protein and enzyme profiles of P. endodontalis, respectively. The results from this study were as follows : 1. The minimal inhibitory concentration(MIC) of poly-P to P. endodontalis appeared to be 0.04~0.05%. 2. Poly-P added to the P. endodontalis culture during the exponential phase of P. endodontalis was as much effective as poly-P added at the begining of the culture, suggesting that the antibacterial effect of poly-P is not much dependent on the initial inoculum size of P. endodontalis. 3. Poly-P are bactericidal to P. endodontalis, demonstrating the decrease of the viable cell counts. 4. Intracellular nucleotide release from the P. endodontalis, was not increased in the presence of poly-P and was not reversed by the addition of divalent cations like $Ca^{2+}$ and $Mg^{2-}$. 5. Under the TEM, it was observed that fine electro-dense materials were prominent in the poly-P grown P. endodontalis, appearing locally in the cell, and the materials were more abundant and more dispersed in the cell as the incubation time with poly-P increased. In addition, highly electron dense granules accumulated in many poly-P grown cells, most of which were atypical in their shape. 6. Binding of 32P-labeled poly-P to P. endodontalis appeared to be 32.8 and 45.5 and 53.4% at 30 minutes, 1 hours and 2 hours, respectively. 7. In the presence of poly-P. the synthesis of proteins with apparent molecular masses of 25, 27, 35, 45 was lost or drastically decreased whereas expression of a protein with an apparent molecular mass of 75 was elevated. 8. Proteolytic activity of P. endodontalis was decreased by poly-P. The overall results suggest that use of poly-P may affect the growth of P. endodontalis, and the anti-bacterial activity of poly-P seems largely bactericidal. Changes in shape, protein expression, and proteolytic activity of P. endodontalis by poly-P may be directly and indirectly attributed to the antibacterial effect of poly-P. Further studies will be needed to confirm the effect of poly-P.

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Surface Texture Changes due to the Oxidation of Pyrite by Acidithiobacillus Ferrooxidans (애시디싸이오바실러스 페로악시댄스에 의한 황철석 산화에 따른 표면 조직의 변화)

  • Yu, Jae-Young;Koh, Hyun-Jin;Song, Hong-Gyu
    • Journal of the Mineralogical Society of Korea
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    • v.24 no.3
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    • pp.235-244
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    • 2011
  • A batch experiment of pyrite oxidation was performed and the surfaces of the reacted pyrite were regularly observed with the scanning electron microscope (SEM) together with the chemical compositions of the solution to help understand the oxidation mechanisms of pyrite by Acidithiobacillus ferrooxidans (Af). The dissolved Fe concentrations clearly indicated that Af experiences the lag and then exponential growth phase. An Af cell was observed to be attached to the surface of pyrite during the lag, implying that a direct leaching by the microbe really happens for the period. It is not certain, however, whether the main mechanism of pyrite oxidation during that time was the direct leaching or not, because there were just a few cells confirmed to be attached and most of the dissolved Fe was Fe(III). The dissolved Fe concentration stayed almost constant from the mid-lag phase to just before the onset of the exponential phase, suggesting that AI needs an adaptation time to switch its oxidation mechanism from one to the other whichever it is during that stage of growth. The moment of Af's cell division was observed by SEM on the surface of pyrite during the lag phase. The corrosion outline around the dividing cell was quite similar to the shape of the cell itself, which implies that the rate of the microbial oxidation is very uneven and the rate when the cell metabolizes should be much faster than that calculated from the concentration variation of the dissolved Fe. The number of etch holes by Af is much higher on the inoculated surfaces, indicating the average rate of pyrite oxidation is also much faster than that of abiotic oxidation. The microbial etch holes on pyrite surface are small and deep, which may influence the transition of the growth phases of Af from lag to exponential.

IN VITRO STUDY OF DEMINERALIZATION INHIBITION EFFECT AND FLUORIDE UPTAKE INTO ADJACENT TEETH OF LIGHT-CURED FLUORIDE-RELEASING RESTORATIVES (수종의 불소방출 수복재의 탈회억제 효과 및 불소침투에 관한 연구)

  • Kim, Song-Yi;Choi, Sung-Chul;Kim, Kwang-Chul;Choi, Yeong-Chul;Park, Jae-Hong
    • Journal of the korean academy of Pediatric Dentistry
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    • v.37 no.3
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    • pp.288-297
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    • 2010
  • The purpose of this study was to evaluate the effect of light cured fluoride-releasing materials on the inhibition of demineralization. In addition, the pattern of fluoride uptake of adjacent tooth structure was analyzed with EPMA. Eighty intact premolars were restored with $Filtek^{TM}$ Z250(control group, composite), Fuji Filling $LC^{TM}$(RMGI), Dyract $AP^{(R)}$ (compomer) and Beautifil II(giomer). Restored teeth were stored in distilled water for 30 days. Then sixty teeth(n=15) were exposed to demineralizing solution(pH 4.3). Demineralized teeth were bisected and polished. The specimens were observed with confocal laser scanning microscope. The depth of outer lesion and the thickness of inhibition zone were measured. Remained twenty teeth(n=5) were bisected for fluoride uptake analysis. The fluoride analysis were taken at enamel-restoration interface and dentin-restoration interface by electron probe micro-analyzer. The results are as follows: 1. The depth of outer lesion of Fuji Filling $LC^{TM}$ Dyract AP, Beautifil II was shallower than that of $Filtek^{TM}$ Z250 at the margin of restoration(p<0.05). 2. The thickness of caries inhibition zone of Fuji Filling $LC^{TM}$, Dyract AP, Beautifil II was greater than that of $Filtek^{TM}$ Z250 at the margin of restoration(p<0.05). 3. Fuji Filling $LC^{TM}$, Dyract AP, Beautifil II groups showed the greater fluoride uptake into enamel and dentine around restoration than $Filtek^{TM}$ Z250 group. 4. In dentin the difference of fluoride concentration were greater than in enamel, and Dyract AP showed the greatest fluoride concentration in dentin.

Improving the efficacy of Lespedeza cuneata ethanol extract on ultraviolet-induced photoaging (야관문 에탄올 추출물의 자외선 노출에 의한 피부 광노화 개선 효과)

  • Jung, Hee Kyoung;Choi, Mi Ok;Kim, Bae Jin;Jo, Seung Kyeung;Jeong, Yoo Seok
    • Food Science and Preservation
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    • v.21 no.2
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    • pp.264-275
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    • 2014
  • This study evaluated the improving efficacy of Lespedeza cuneata ethanol extract on skin photoaging induced by ultraviolet (UV) irradiation. The total polyphenol and flavonoid contents of the extract were respectively $134.98{\pm}1.70$ and $16.20{\pm}0.05$ mg/g, respectively. The superoxide anion radical scavenging activity and electron-donating ability of the extract were shown to be dependent on concentration, and the antioxidant ability was shown to be more effective in superoxide anion radical scavenging activity than in electron-donating ability under the same concentration conditions. In the in vivo test conducted using hairless mouse with skin photoaging induced by UVB irradiation, the skin erythema of the groups treated with the extract (AS) reduced to 28% of the control, and the skin moisture content increased to 131%.. The extract treatment of the UV-damaged skin improved the morphological and histopathological state of the skin. Furthermore, the SOD, GST and CAT activities in the skin tissue of the AS group increased, and the XO activity and TBARS generation decreased. With regard to the genes related to the photoaging skin, the expression of PAK, p38, c-Fos, c-Jun, TNF-${\alpha}$ and MMP-3 in the skin of the AS group were found to have decreased. It was therefore concluded that Lespedeza cuneata ethanol extract can reduce wrinkle formation in the skin due to the regulation of the gene expression caused by the exposure to UVB light.

Optimization of Extraction of Effective Components from Vitis coignetiae, the Crimson Glory Vine (산머루 유용성분 추출공정의 최적화)

  • Jo, In-Hee;Kim, Chang-Youn;Lee, Tae-Wook;Lee, Geun-Ho;Choi, Yong-Hee
    • Food Science and Preservation
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    • v.17 no.5
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    • pp.659-666
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    • 2010
  • A central composite design was used to investigate the effects of the three independent variables of extraction temperature ($X_1$), ethanol concentration ($X_2$), and extraction time ($X_3$), on dependent variables including yield ($Y_1$), total phenol levels ($Y_2$), electron-donating ability ($Y_3$), brownness ($Y_4$), and reducing sugar content ($Y_5$) of Vitis Coignetiae. Yield was affected by extraction temperature and time. The maximum yield was obtained at $91.62^{\circ}C(X_1)$, and, 25.37% (w/v) ethanol ($X_2$), after 317.70 min of extraction ($X_3$), evident as a saddle when displayed graphically. Total phenol levels were essentially unaffected by extraction temperature or ethanol concentration, but were highly influenced by extraction time. The maximum total phenol levels was 4,763.46 GAE mg/100 g obtained at $88.20^{\circ}C(X_1)$, and 47.79% (w/v) ethanol ($X_2$), after 349.32 min ($X_3$) of extraction. Electron-donating ability (EDA) was affected by extraction temperature and time. Maximum EDA was 55.90% at $86.72^{\circ}C(X_1)$, 50.61% (w/v) ethanol ($X_2$), and 265.96 min ($X_3$) of extration time, again shown by a graphical saddle. Brownness was affected by extraction time. The maximum extent of brown coloration was obtained at $82.66^{\circ}C(X_1)$, 99.27% (w/v) ethanol ($X_2$), and 252.63 min of extraction time ($X_3$), once again shown by graphical saddle. The maximum reducing sugar content was obtained at $96.24^{\circ}C(X_1)$, 22.59% (w/v) ethanol ($X_2$), and 216.06 min extraction time($X_3$).

Antioxidant Activities of Phenolic Compounds from Medicinal Plants (Hibiscus esculentus, Cirsium japonicum, Zizania latifolia and Kalopanax pictus) (약용식물(오크라, 엉컹퀴, 엄나무, 줄풀) 유래 페놀성 물질의 항산화 활성)

  • Choi, Jin-Young;Jo, Min-Kyeong;Goo, Young-Mi;Kim, Hyun-Kyung;Shin, Jin-Won;Kim, Dong-Yeong;Kim, Hye-Jin;Lee, Eun-Ho;Kim, Na-Hyun;Cho, Young-Je
    • Current Research on Agriculture and Life Sciences
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    • v.33 no.2
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    • pp.57-63
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    • 2015
  • In this study, the antioxidant activity of water and ethanol extracts from Hibiscus esculentus, Cirsium japonicum, Zizania latifolia and Kalopanax pictus for functional food source were examined. The optimal conditions for phenolic compounds extraction from medicinal plants were at 50% ethanol with Hibiscus esculentus and Cirsium japonicum var. ussuriense, at 40% ethanol with Kalopanax pictus and at 60% ethanol with Zizania latifolia. The total phenolic contents from the extracts of medical plants were determined to be 2.72~34.15 mg/g in the water extracts and 2.83~34.23 mg/g in the ethanol extracts. The electron-donating abilities (EDA) of the water and ethanol extracts were both above 74% at the low concentration of $50{\mu}g/mL$. The ABTS radical-cation decolorization was above 88% at $100{\mu}g/mL$ concentration in all the extracts of various medicinal plants. The antioxidant protection factor (PF) in the water and ethanol extracts of the Cirsium japonicum var. ussuriense extracts was $1.73{\pm}0.02PF$ and $1.76{\pm}0.01PF$ at $50{\mu}g/mL$ concentration respectively, and was higher than those of the other medicinal-plant extracts. The TBARs inhibition rates of all the medicinal-plant extracts, were above 80% at the $50{\mu}g/mL$ concentration except Hibiscus esculentus. These results confirmed that the various oriental medicinal plants (Hibiscus esculentus, Cirsium japonicum var. ussuriense, Kalopanax pictus and Zizania latifolia) that were included in this study are useful anti-oxidant and functional-food resources.

A Study on Treatment of Soils Contaminated by Diesel and Kerosene Using Hydrogen Peroxide Catalyzed by Naturally Occurring Iron Minerals (디젤과 등유로 오염된 토양의 철광석으로 촉매화된 과수를 이용한 처리에 관한 연구)

  • Choi, Jin-Ho;Kim, Sang-Dae;Moon, Sei-Ki;Kong, Sung-Ho
    • Applied Chemistry for Engineering
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    • v.10 no.1
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    • pp.24-29
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    • 1999
  • Naturally-occurring iron minerals, goethite, magnetite, and hydrogen peroxide were used to catalyze and initiate Fenton-like oxidation of silica sand contaminated with mixture of diesel and kerosene in batch system. Optimal reaction conditions were investigated by varying pH(3, 7), $H_2O_2$ concentration(0%, 1%, 7%, 15%, 35%), initial contaminant concentration(0.2, 0.5, 1.0 g-mixture of diesel and kerosene/ kg-soil), and iron mineral contents(1, 5, and 10 wt % magnetite or goethite). Contaminant degradations in silica sand-iron mineral-$H_2O_2$ systems were identified by determining total petroleum hydrocarbon(TPH) concentration. The optimal pH of the system was 3. The system which iron minerals were the only iron source was more efficient than the system with $FeSO_4$ solution due to lower $H_2O_2$ consumption. In case of initial contaminant concentration of 1g-contaminant/kg-soil with 5 wt % magnetite, addition of 0%, 1%, 7%, 15%, and 35% of $H_2O_2$ showed 0%, 24.5%, 44%, 52%, and 70% of TPH reduction in 8 days, respectively. When the mineral contents were varied 0, 1, 5, and 10wt%, removal of contaminants were 0%, 33.5%, 50%, and 60% for magnetite and 0%, 29%, 41%, and 53% for goethite, respectively. Reaction of magnetite system showed higher degradation than that of goethite system due to dissolution of iron and mixed presence of iron(II) and iron(III); however, dissolved iron precipitated on the surface of iron mineral and seemed to cause reducing electron transfer activity on the surface and quenching $H_2O_2$. The system using goethite has better treatment efficiency due to less $H_2O_2$ consumption. When cach system was mixed by shaker, removal of contaminants increased by 41% for magnetite and 30% for goethite. Results of this study showed catalyzed $H_2O_2$ system made in-situ treatment of soil contaminated with petroleum possible without addition of iron source since natural soils generally contain iron minerals such as magnetite and goethite.

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Antioxidant and Angiotensin Converting Enzyme I Inhibitory Activities of Extracts from Mulberry (Cudrania tricuspidata) Fruit subjected to Different Drying Methods (건조방법에 따른 꾸지뽕열매 추출물의 항산화활성과 Angiotensin Converting Enzyme I 저해활성)

  • Youn, Kwang-Sup;Kim, Jae-Won
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.10
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    • pp.1388-1394
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    • 2012
  • The physiological functionalities of 70% ethanol extracts (EE) from Cudrania tricuspidata fruit (ECFD, EE of C. tricuspidata subjected to freeze-drying; ECHD, EE of C. tricuspidata subjected to heat air drying; ECID, EE of C. tricuspidata subjected to infrared drying) were investigated. Yields of freeze-dried powders of ECFD, ECHD, and ECID were 51.50%, 53.91%, and 56.14%, respectively. Color $L^*$, $a^*$, $b^*$, and $H^{\circ}$ values of ECHD and ECID decreased. Dried ECHD and ECID had relatively higher contents of total polyphenolics and flavonoids than ECFD. Electron donating abilities at a concentration of 10 mg/mL (w/v) were in order of ECID (62.37%) >ECHD (80.17%)>ECFD (77.80%). Reducing powers ($OD_{700}$) of ECFD, ECHD, and ECID were 0.75, 1.70, and 1.89, respectively. Additionally, ABTS radical scavenging ability of ECID was the highest with a value of 62.37% at a concentration of 10 mg/mL (w/v). Nitrite scavenging activities of ECFD, ECHD, and ECID at a concentration of 10 mg/mL (w/v) were 28.76%, 30.69%, and 41.64%, respectively. SOD (superoxide dismutase)-like activities at 5 mg/mL (w/v) were in the order ECFD (891.93 mUnits)>ECHD (723.02 mUnits)>EFID (611.97 mUnits). Whereas ferrous ion chelating activity of ECFD (52.36%) and ECID (47.16%) was significantly higher than that of ECHD (30.04%). ACE inhibitory and xanthine oxidase (XO) inhibitory activities of ECHD and ECID at a concentration of 1 mg/mL (w/v) were higher than those of ECFD. In conclusion, we provided experimental evidence that extracts of pre-dried C. tricuspidata exhibit increased physiological functionalities. Further, infrared drying technique is the best method for enhancement of antioxidant activity of C. tricuspidata fruit.

A Study on the Whitening Effect of Erigeron annuus (L.) Pers. Ethanol Extract on Melanoma Cell (B16F10) (멜라노마 세포(B16F10)에서의 개망초 추출물을 이용한 미백효과에 관한 연구)

  • Joo, Da-Hye;Yoo, Dan-Hee;Lee, Jin-Young
    • Microbiology and Biotechnology Letters
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    • v.47 no.1
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    • pp.148-157
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    • 2019
  • A 70% ethanol extract of Erigeron annuus (L.) Pers. was investigated for its whitening activity for application as a functional ingredient in cosmetic products. At the E. annuus extract concentration of $100{\mu}g/ml$, the electron-donating ability was found to be 67.83%, the tyrosinase inhibitory effect (related to skin-whitening) was 69%, the elastase inhibitory effect (related to skin-wrinkling) was 69%, and the astringent effect was 80%. The $ABTS^+$ radical-scavenging ability was 87% at the $500{\mu}g/ml$ concentration. In the cell viability test measured on melanoma cells, 96% of the cells treated with $100{\mu}g/ml$ of the extract were viable. According to the western blot results, the protein expression of the microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 was decreased by 60.22%, 47.83%, 54.79%, and 67.88%, respectively, at the extract concentration of $100{\mu}g/ml$. The protein expression of phosphorylated extracellular signal regulated kinase (p-ERK) and phosphorylated cAMP response element-binding protein (p-CREB) was decreased with increasing concentrations of the extract. Reverse transcription-polymerase chain reaction of the extract showed that the mRNA expression of MITF, tyrosinase, TRP-1, and TRP-2 was decreased by 86.51%, 85.22%, 74.26%, and 66.66%, respectively, at $100{\mu}g/ml$ extract concentration. The findings suggest that the 70% ethanol extract from E. annuus (L.) Pers. has potential as a cosmeceutical ingredient with whitening effect.