Antioxidant and Anti-Tyrosinase Activity from Olea Leaf Extract Depended on Seasonal Variations and Chromagraphy Treatment

Yang, Daomao; Ouyang, Mi

doi:10.4236/ijoc.2012.24054

Cited by 9 publications

(6 citation statements)

References 18 publications

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“…Comparing data for AOA the highest values were observed for cultivar Chondrolia Halkidiki grown in vitro and in vivo. Presented results are in accordance with Yang and Ouyang (2012) and Lafka et al (2013) confirming the highest antioxidant potential of olive leaf extracts. Present investigation demonstrated that in vitro plants possess higher content of TPC and AOA in comparison with in vivo cultivated olive plants.…”

Section: Resultssupporting

confidence: 89%

“…Recent studies have shown that compounds, derivatives from the leaves and fruits of the olive tree are strong antioxidants (Kontogianni and Gerothanassis, 2012). For the leaf extracts is proved antimalarial, anti-HIV action, vasomotor and hypoglycemic effects (Yang and Ouyang, 2012;Lafka et al, 2013). Many reports indicate that olive leaves contain significant amounts of oleuropein and phenols possessing high antioxidant capacity (Mourtzinos et al, 2007;Lee et al, 2009;Abaza et al, 2011).…”

Section: Introductionmentioning

confidence: 99%

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Polyphenol profile and antioxidant activity of extracts from olive leaves

Yancheva¹,

Mavromatis²,

Georgieva³

2016

j. cent. eur. agric.

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The compounds, derivatives of olive leaves have a high antioxidant activity. The content of the total phenolic compounds (TPC), antioxidant activity (AOA) and HPLC polyphenol profile of methanol extracts from the leaves of the olive cultivars Chondrolia Halkidiki, Kalamon, Koroneiki grown in the nursery (in vivo) and in vitro plants of Chondrolia Halkidiki were compared. The results obtained for TPC varied between 9.2±0.5 mgGAE*gDW -1 and 16.4±0.5 mgGAE*gDW -1 . Antioxidant capacity was determined by four methods DPPH, ABTS, FRAP and CUPRAC. The highest results for TPC and AOA were achieved for the leaves of Chondrolia Halkidiki grown in vitro. A high correlation between the results gained from the TPC and AOA was established. Conducted HPLC analysis revealed the presence of 3,4-dihydroxybenzoic, caffeic, sinapic and ferulic acids and quercetin, hesperidin and luteolin and the quercetin glycosides rutin and hyperoside.

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Section: Resultssupporting

confidence: 89%

Section: Introductionmentioning

confidence: 99%

Polyphenol profile and antioxidant activity of extracts from olive leaves

Yancheva¹,

Mavromatis²,

Georgieva³

2016

j. cent. eur. agric.

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“…Kinetic data analysis using Lineweaver-Burk plot, which is also called the double reciprocal plot reveals that the inhibitory mechanism of both methanol leaf extracts on mushroom tyrosinase was competitive, viz partial competitive inhibition. This correlates with Yang and Quyang [19] conclusion for Olea leaf extract analysed by Lineweaver-Burk plot. Furthermore, L. esculentum var.…”

Section: Discussionsupporting

confidence: 87%

“…This implies that methanol leaf extract of Eva F1 variety has a higher affinity for the active site of mushroom tyrosinase than that of Hausa variety. Also, the K I value obtained in this study is considerably lower than that obtained by Yang and Quyang [19] for Olea europa leaf extract, which had a K I value of 0.226 mg/mL.…”

Section: Discussioncontrasting

confidence: 87%

Phytochemical screening, antioxidant and tyrosinase inhibitory studies of methanol leaf extracts of two tomato varieties

Omotoyinbo

Awojulu

Sanni

2020

Highlights in BioScience

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This study evaluated the phytochemical compositions, antioxidant properties, chlorophyll content and anti-tyrosinase activity of methanol leaf extracts of two tomato varieties, Lycopersicon esculentum (var. Eva F1) and Lycopersicon esculentum Mill (var. Hausa). The dried pulverized of the plant’s leaves were extracted by decoction and mild agitation. Phytochemicals such as flavonoids, tannin, glycoside, saponin, terpenoid and anthraquinone were present in the extracts of both varieties examined, while alkaloid and phlobatannin were confirmed absent in the extracts. The presence of steroid was observed in var. Eva F1 but absent in var. Hausa. Total phenolic content (TPC) and total flavonoid content (TFC) of var. Eva F1 were 505.9 ± 2.61 mg GAE/ge, and 35.5 ± 1.64 mg RE/ge, while var. Hausa recorded a TPC and TFC value of 344.3 ± 2.01 and 7.8 ± 0.15 mg RE/ge respectively. The chlorophyll content of the extracts were 6.6 ± 0.02 mg/ge (chlorophyll a), 5.7 ± 0.05 mg/ge (chlorophyll b) and 12.6 ± 0.14 mg/ge (total chlorophyll content) for Eva F1 variety, while the chlorophyll contents for var. Hausa were 7.6 ± 0.32 mg.ge (chlorophyll a), 5.6 ± 0.06 mg/ge (chlorophyll b) and 13.7 ± 0.14 mg/ge. Eva F1 and Hausa showed percentage inhibition of 76.3 % and 61.2 % at 400 μg/mL. The IC50 value of var. Eva F1 and var. Hausa were 110 μg/mL and 160 μg/mL. The inhibition constant (KI) of var. Eva F1 and var. Hausa, were 0.006 and 0.016 μg/mL, respectively, and both extracts showed partial competitive inhibition. Hence, this confirms the phytoprotective and tyrosinase inhibitory properties of tomato plant leaves.

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“…The activity of mushroom Tyr was measured following the method described earlier by Yang and Ouyang. 21 The conditions of the enzymatic crosslinking reactions were decided based on a previous study 22 and pre-experiments. Figure 1(A) displays the reaction formula showing the crosslinking reaction.…”

Section: Crosslinking Of Fish Pv By Tyr In the Presence Of Camentioning

confidence: 99%

Effect of tyrosinase‐catalyzed crosslinking on the structure and allergenicity of turbot parvalbumin mediated by caffeic acid

Tian

Ahmed

et al. 2019

J Sci Food Agric

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BACKGROUND Enzymatic treatment of allergenic protein can alter their functional properties under a mild reaction condition due to specificity of enzymes. Phenolic compounds act as mediators and enhance the crosslinking reactions. The study aimed to assess the changes in the structure and immunoglobulin G (IgG) binding capacity of turbot parvalbumin (PV) upon crosslinking with tyrosinase (Tyr) in the absence and presence of caffeic acid. RESULTS Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) analysis revealed the appearance of higher molecular weight bands (24, 36 kDa) in the crosslinked PV. The secondary structure of crosslinked PV became loosened and disordered. The results of intrinsic fluorescence and ultraviolet absorption spectral analyses, as well as surface hydrophobicity and free amino group analyses also revealed structural changes. As observed by western blot analysis, the intensity of the PV bands reduced upon Tyr treatment, indicating reduced binding of specific IgG to PV. Moreover, the indirect ELISA (enzyme‐linked immunosorbent assay) analysis confirmed that the IgG binding ability of crosslinked PV was reduced 34.94%. CONCLUSION Enzymatic treatment mitigated the allergenicity of fish PV, which was closely related to the alterations in the conformational structure. This treatment showed potential for developing hypoallergenic fish products under mild reaction conditions. © 2019 Society of Chemical Industry

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Antioxidant and Anti-Tyrosinase Activity from Olea Leaf Extract Depended on Seasonal Variations and Chromagraphy Treatment

Cited by 9 publications

References 18 publications

Polyphenol profile and antioxidant activity of extracts from olive leaves

Polyphenol profile and antioxidant activity of extracts from olive leaves

Phytochemical screening, antioxidant and tyrosinase inhibitory studies of methanol leaf extracts of two tomato varieties

Effect of tyrosinase‐catalyzed crosslinking on the structure and allergenicity of turbot parvalbumin mediated by caffeic acid

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