scholarly journals Antityrosinase activity ofEuphorbia characiasextracts

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1305 ◽  
Author(s):  
Francesca Pintus ◽  
Delia Spanò ◽  
Angela Corona ◽  
Rosaria Medda

Tyrosinase is a well-known key enzyme in melanin biosynthesis and its inhibitors have become increasingly important because of their potential use as hypopigmenting agents. In the present study, the anti-melanogenic effect of aqueous and ethanolic extracts fromEuphorbia characiasleaves, stems, and flowers in cell-free and cellular systems was examined. All the extracts showed inhibitory effects against mushroom tyrosinase with leaf extracts exhibiting the lowest IC50values of 24 and 97 µg/mL for aqueous and ethanolic extracts respectively. Enzyme kinetic analysis indicated that leaf aqueous extract acts as a mixed type inhibitor, while ethanolic extract shows a competitive inhibition effect on mushroom tyrosinase using L-DOPA as substrate. In addition, the inhibitory effect of leaf extracts on tyrosinase activity and melanin production was examined in murine melanoma B16F10 cells. Cellular tyrosinase activity as well as levels of melanin synthesis are reduced in a dose-dependent manner by extracts in cells treated withα-melanocyte stimulating hormone (α-MSH). The effects are comparable, and sometimes even better, than that of kojic acid, a well known tyrosinase inhibitor used for reference. All these results suggest thatE. characiascould be a great source of the natural inhibitors from tyrosinase and has the potential to be used as a whitening agent in therapeutic fields.

2004 ◽  
Vol 32 (01) ◽  
pp. 97-103 ◽  
Author(s):  
Jae Kyung No ◽  
Min Sun Kim ◽  
You Jung Kim ◽  
Song Ja Bae ◽  
Jae Sue Choi ◽  
...  

The purpose of this study was to determine the inhibitory action of protocatechuic aldehyde (PCA) on tyrosinase activity. PCA is one of the compounds found in the root of Salvia miltiorrhiza. Our study documented that PCA has a potent inhibitory effect on tyrosinase, which catalyzes the rate-limiting step of melanin biosynthesis. Although melanin biosynthesis has an essential function normally in human skin for defense against ultraviolet light of the sun, its abnormal activity as seen in pigmentation disorder could lead to serious medical problems. Our data showed that PCA, with concentrations ranging from 1×10-5 M to 8×10-5 M , exhibited dose-dependent inhibition of the enzyme activity with 50% of inhibition at 19.92×10-6 M . A further kinetic analysis on PCA inactivation of tyrosinase activity revealed a competitive inhibition of the enzyme at the L-tyrosine binding site. The findings of our present study merit further research on the applicability of PCA as a potential agent for treatment of pigmentation disorder.


2019 ◽  
Vol 819 ◽  
pp. 118-123
Author(s):  
Wassana Riam-Amatakun ◽  
Panupan Limpachayaporn ◽  
Jhoan Rhea L. Pizon ◽  
Praneet Opanasopit ◽  
Nopparat Nuntharatanapon

Melanin is cutaneous pigment which level of its production determines skin complexion. Overproduction of melanin, frequently promoted by UV rays, results in darkening of the skin. Inhibition of tyrosinase activity, a core component in melanin biosynthesis, is one of the mechanisms of depigmenting agents. Hydroquinone and kojic acid are the examples of well-known whitening agents widely used in both pharmaceutical and cosmetic products. However, their adverse effect issues still needed to be overcome. A recent study showed that p-chlorophenyl benzyl ether (Cl-benz), a new synthetic compound, more strongly inhibited mushroom tyrosinase than kojic acid. In the current study, cytotoxicity, anti-melanogenic activity and anti-tyrosinase activity of Cl-benz were performed in mouse B16F10 melanoma cells compared to kojic acid. After 24 h of treatment on B16F10 cells, the cytotoxicity was not observed with Cl-benz and kojic acid. However, after incubation for 48 h, kojic acid at a concentration of 500 μM reduced cell viability less than 50%, whereas Cl-benz-treated cells showed negligible cytotoxicity. For cell-based assay, Cl-benz exhibited inhibitory effect similar to kojic acid. Melanin production in B16F10 cells was suppressed by Cl-benz in a dose dependent manner. One hundred micrograms of Cl-benz decreased melanin content in α-MSH by 66%. Moreover, the percentage of cellular tyrosinase activity of Cl-benz showed positive association with its corresponding melanin content. These results revealed that Cl-benz could inhibit melanogenesis via the mechanism of cellular tyrosinase inhibition. Accordingly, Cl-benz has potential to become a novel skin whitening agent in terms of efficacy and safety.


2013 ◽  
Vol 31 (2) ◽  
pp. 239-248 ◽  
Author(s):  
P.U. Grisi ◽  
S.C.J. Gualtieri ◽  
S. Anese ◽  
V.C. Pereira ◽  
M.R. Forim

The objective of this study was to evaluate the effect of the ethanolic extract of Serjania lethalis leaves and stems on the diaspore germination and seedling growth of wild poinsettia (Euphorbia heterophylla) and barnyardgrass (Echinochloa crus-galli). The crude ethanolic extract was prepared from 100 g of dry plant material dissolved in 500 ml of ethanol. The extracts were solubilized in a buffer solution containing dimethyl sulfoxide (DMSO) at concentrations of 10.0, 7.5, 5.0 and 2.5 mg mL-1. The effect of these extracts was compared with herbicide oxyfluorfen in bioassays. The ethanolic extracts of S. lethalis leaves and stems inhibited the germination and seedling growth of barnyardgrass and wild poinsettia in a concentration-dependent manner. The reduction in the root length of E. heterophylla seedlings might be attributed to the reduced elongation of metaxylem cells. The phytotoxicity of the extracts ranged according to the receptor species, and for some variables, the inhibitory effect was similar, and even superior, to that of the commercial herbicide. Thus, S. lethalis extracts might be a promising alternative for sustainable weed management.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Na Liu ◽  
Ping Chen ◽  
Xiaojun Du ◽  
Junxia Sun ◽  
Shasha Han

Abstract Background Obtusofolin is the major active ingredient of Catsia tora L., which possesses the activity of improving eyesight and protecting the optic nerve. Investigation on the interaction of obtusofolin with cytochrome P450 enzymes (CYP450s) could provide a reference for the clinical application of obtusofolin. Methods The effect of obtusofolin on the activity of CYP450s was investigated in the presence of 100 μM obtusofolin in pooled human liver microsomes (HLMs) and fitted with the Lineweaver–Burk plots to characterize the specific inhibition model and kinetic parameters. Results Obtusofolin was found to significantly inhibited the activity of CYP3A4, 2C9, and 2E1. In the presence of 0, 2.5, 5, 10, 25, 50, and 100 μM obtusofolin, the inhibition of these CYP450s showed a dose-dependent manner with the IC50 values of 17.1 ± 0.25, 10.8 ± 0.13, and 15.5 ± 0.16 μM, respectively. The inhibition of CYP3A4 was best fitted with the non-competitive inhibition model with the Ki value of 8.82 μM. While the inhibition of CYP2C9 and 2E1 was competitive with the Ki values of 5.54 and 7.79 μM, respectively. After incubating for 0, 5, 10, 15, and 30 min, the inhibition of CYP3A4 was revealed to be time-dependent with the KI value of 4.87 μM− 1 and the Kinact value of 0.0515 min− 1. Conclusions The in vitro inhibitory effect of obtusofolin implying the potential drug-drug interaction between obtusofolin and corresponding substrates, which needs further in vivo validations.


2012 ◽  
Vol 35 (6) ◽  
pp. 993-996 ◽  
Author(s):  
Miyako Yanagihara ◽  
Maiko Yoshimatsu ◽  
Akinori Inoue ◽  
Tomoko Kanno ◽  
Tomoki Tatefuji ◽  
...  

2019 ◽  
Vol 14 (6) ◽  
pp. 1934578X1985852 ◽  
Author(s):  
You C. Chung ◽  
Min-Jin Kim ◽  
Eun Y. Kang ◽  
Yun B. Kim ◽  
Bong S. Kim ◽  
...  

Melanin plays a role in determining human skin color of a person, and a large amount of melanin makes the skin color look darkened. The proper amount of melanin formation protects our skin from UV radiation, but excessive melanin production causes hyperpigmentation and leads to freckles, melasma, and lentigo. In this study, we investigated the inhibitory effect of hydroxyectoine on melanogenesis and its mechanism in B16F10 cells. Melanin content and cellular tyrosinase activity were determined. The expression of microphthalmia-associated transcription factor (MITF), and the activities of tyrosinase and other melanogenesis-related enzymes, such as tyrosinase-related protein 1 (TRP-1) and tyrosinase-related protein 2, were also examined. Hydroxyectoine treatment significantly inhibited melanin production and intracellular tyrosinase activity in a dose-dependent manner. Western blot analysis showed that hydroxyectoine also reduced the expressions of tyrosinase and TRP-1. In addition, hydroxyectoine significantly reduced the expression of MITF, a major regulator of melanin production, and inhibited the phosphorylation of p38, c-Jun N-terminal kinase, and activated the protein kinase B. The results demonstrated that hydroxyectoine inhibits the expression of MITF through the inhibition or activation of melanin-related signaling pathways and downregulates melanogenesis by inhibiting melanogenic enzyme expression and tyrosinase activity. Hydroxyectoine has potential value in functional cosmetics applications, such as whitening.


2019 ◽  
Vol 891 ◽  
pp. 52-59
Author(s):  
Chanai Noysang ◽  
Teerarat Pummarin

Benchalokawichian (BLW) remedy is a Thai traditional medicine that has been notified in the List of Medicine Products of the National List of Essential Drugs A.D. 2006 and has long been used as an antipyretic. The phytochemicals of the 70% and 95% ethanolic extracts of were studied by color reaction test and HPTLC analysis. The BLW remedy showed a highest amounts of 70% ethanolic extractives (ca. 3.99 ± 0.60% of dry material weight). The several ethanolic extracts showed similar qualitative phytochemicals. The major of phytochemicals identified in these extracts were alkaloids, flavonoids, tannins, and polyphenols. The antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl assay. The analysed 70% ethanolic extract showed a highest antioxidant activity at IC50= 526.09 µg/ml and both extracts not showed tyrosinase inhibitory effect. The 95% ethanolic extract showed the greatest anti-propionibacterium acnes activity with inhibition zone of 10.10 ± 0.45 mm and minimum inhibitory concentration (MIC) was 5.05 mg/ml


2019 ◽  
Vol 891 ◽  
pp. 41-51
Author(s):  
Chanai Noysang ◽  
Nutsuda Boonmatit

The phytochemicals of the ethanolic extracts of petals and stamens of lotus flowers from several lotus cultivars belonging to the Nelumbo nucifera Gaertn. (namely 'lotus white flower' and 'lotus pink flower') were studied by color reaction test and HPTLC analysis. The lotus pink flower stamens showed a highest amount of ethanolic extractives (ca. 18.33±2.14% of dry material weight). The several the ethanolic extracts of N. nucifera petals and stamens showed similar qualitative phytochemicals. The crude extracts revealed the presence of flavonoids, terpenoinds, tannins and polyphenols. The antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl assay. The analyzed lotus pink flower stamens ethanolic extract showed a highest antioxidant activity at IC50 = 0.61±0.16 μg/ml and lotus pink flower petals ethanolic extract showed a highest tyrosinase inhibitory effect at IC50 = 2.25±0.21 μg/ml. N. nucifera flowers could be provide a potential natural source of phytochemicals and could be beneficial to the cosmetic properties.


Antioxidants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 449 ◽  
Author(s):  
Yunju Woo ◽  
Ji Sun Lim ◽  
Jisun Oh ◽  
Jeong Soon Lee ◽  
Jong-Sang Kim

Euonymus alatus is considered to elicit various beneficial effects against cancer, hyperglycemia, menstrual discomfort, diabetic complications, and detoxification. The young leaves of this plant are exploited as food and also utilized for traditional medicine in East Asian countries, including Korea and China. Our preliminary study demonstrated that ethanolic extract from the Euonymus alatus leaf (EAE) exhibited the strongest antioxidant enzyme-inducing activity among more than 100 kinds of edible tree leaf extracts. This study investigated whether EAE could attenuate the cognitive deficits caused by oxidative stress in mice. Oral intubation of EAE at 100 mg/kg bw or higher resulted in significant improvements to the memory and behavioral impairment induced via i.p. injection of scopolamine. Furthermore, EAE enhanced the expression levels of hippocampal neurotrophic factors such as brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor in mice, activated the Nrf2, and the downstream heme oxygenase-1 (HO-1) a quintessential antioxidant enzyme. As rutin (quercetin-3-O-rutinose) was abundantly present in EAE and free quercetin was able to induce defensive antioxidant enzymes in an Nrf2-dependent manner, our findings suggested that quercetin derived from rutin via the intestinal microflora played a significant role in the protection of the mouse hippocampus from scopolamine-induced damage through BDNF-mediated Nrf2 activation, thereby dampening cognitive decline.


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