scholarly journals Effect of Ferrous Ion on Heat-Induced Aroma Deterioration of Green Tea Infusion

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4255
Author(s):  
Ying Gao ◽  
Jie-Qiong Wang ◽  
Jian-Xin Chen ◽  
Fang Wang ◽  
Gen-Sheng Chen ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Hydrogen Peroxide ◽  
Green Tea ◽  
Underlying Mechanism ◽  
Ferrous Ion ◽  
Tea Infusion ◽  
Ms Analysis ◽  
Production Of Hydrogen ◽  
Aroma Characteristics

Aroma deterioration is one of the biggest problems in processing tea beverages. The aroma of tea infusion deteriorates fast during heat sterilization and the presence of ferrous ion (Fe2+) aggravates it. The underlying mechanism remains unveiled. In this study, Fe2+ was verified to deteriorate the aroma quality of green tea infusion with heat treatment. Catechins were necessary for Fe2+-mediated aroma deterioration. By enhancing the degradation of catechins, Fe2+ dramatically increased the production of hydrogen peroxide (H2O2). Fe2+ and H2O2 together exacerbated the aroma of green tea infusion with heat treatment. GC-MS analysis revealed that the presence of Fe2+ enhanced the loss of green/grassy volatiles and promoted the formation of new volatiles with diversified aroma characteristics, resulting in a dull scent of green tea infusion. Our results revealed how Fe2+ induced aroma deterioration of green tea infusion with heat treatment and could help guide tea producers in attenuating the aroma deterioration of tea infusion during processing.

The protective effect of melatonin on the in vitro development of yak embryos against hydrogen peroxide-induced oxidative injury

Zygote ◽  
2019 ◽  
Vol 27 (3) ◽  
pp. 118-125 ◽  
Author(s):  
Wei Peng ◽  
Mengtong Lei ◽  
Jun Zhang ◽  
Yong Zhang
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Critical Role ◽  
Underlying Mechanism ◽  
Preimplantation Embryos ◽  
Effective Antioxidant ◽  
Vitro Development ◽  
Oxidation Effect

SummaryMelatonin plays a critical role in several types of cells as an antioxidant to protect intracellular molecules from oxidative stress. The anti-oxidation effect of melatonin in yak embryos is largely unknown. We report that melatonin can protect the development of yak preimplantation embryos against oxidative stress induced by hydrogen peroxide (H2O2). Therefore, the quality of blastocysts developed from zygotes exposed to H2O2 was promoted. In addition, we observed that melatonin reduced H2O2-induced intracellular reactive oxygen species (ROS) levels and prevented mitochondrial dysfunction in zygotes. These phenomena revealed the effective antioxidant activity of melatonin to prevent oxidative stress in yak embryos. To determine the underlying mechanism, we further demonstrated that melatonin protected preimplantation embryos from oxidative damage by preserving antioxidative enzymes. Collectively, these results confirmed the anti-oxidation effect of melatonin in yak embryos that significantly improved the quantity and quality of blastocysts in the in vitro production of embryos in yaks.

scholarly journals Hyperglycemia Promotes the Epithelial-Mesenchymal Transition of Pancreatic Cancer via Hydrogen Peroxide

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Wei Li ◽  
Lun Zhang ◽  
Xin Chen ◽  
Zhengdong Jiang ◽  
Liang Zong ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Hydrogen Peroxide ◽  
Nude Mice ◽  
Epithelial Mesenchymal Transition ◽  
Metastatic Potential ◽  
Underlying Mechanism ◽  
Related Factors ◽  
Mesenchymal Transition ◽  
Pancreatic Cancer Cells ◽  
Production Of Hydrogen

Diabetes mellitus (DM) and pancreatic cancer are intimately related, as approximately 85% of patients diagnosed with pancreatic cancer have impaired glucose tolerance or even DM. Our previous studies have indicated that high glucose could promote the invasive and migratory abilities of pancreatic cancer cells. We therefore explored the underlying mechanism that hyperglycemia modulates the metastatic potential of pancreatic cancer. Our data showed that streptozotocin- (STZ-) treated diabetic nude mice exhibit larger tumor size than that of the euglycemic mice. The number of nude mice that develop liver metastasis or ascites is much more in the STZ-treated group than that in the euglycemic group. Hyperglycemic mice contain a higher plasma H2O2-level than that from euglycemic mice. The injection of polyethylene glycol-conjugated catalase (PEG-CAT), an H2O2scavenger, may reverse hyperglycemia-induced tumor metastasis. In addition, hyperglycemia could also modulate the expression of epithelial-mesenchymal transition- (EMT-) related factors in pancreatic tumor tissues, as the E-cadherin level is decreased and the expression of mesenchymal markers N-cadherin and vimentin as well as transcription factor snail is strongly increased. The injection of PEG-CAT could also reverse hyperglycemia-induced EMT. These results suggest that the association between hyperglycemia and poor prognosis of pancreatic cancer can be attributed to the alterations of EMT through the production of hydrogen peroxide.

scholarly journals An Increase in Antibacterial Activity of Green Tea Infusion by Heat-Treatment.

2000 ◽  
Vol 47 (9) ◽  
pp. 708-715 ◽  
Author(s):  
Masashi ASAKA ◽  
Keiko MURAI ◽  
Ritsuko NAKANISHI ◽  
Yosio AOYAMA
Keyword(s):  
Heat Treatment ◽  
Antibacterial Activity ◽  
Green Tea ◽  
Tea Infusion

Effect of Pasteurization, Centrifugation and Additives on Quality of Concentrated Yogurt (Labneh)

1985 ◽  
Vol 48 (4) ◽  
pp. 300-302 ◽  
Author(s):  
S. DAGHER ◽  
A. ALI
Keyword(s):  
Heat Treatment ◽  
Hydrogen Peroxide ◽  
Bacterial Count ◽  
Potassium Sorbate ◽  
Bacterial Cells ◽  
Low Levels ◽  
Heat Pasteurization ◽  
Short Time ◽  
Pronounced Reduction

Pasteurization of yogurt by heat at 60–80°C or by addition of 0.2 to 2% hydrogen peroxide were investigated. Heat-treatment caused a very pronounced reduction in the bacterial count of yogurt samples. Addition of hydrogen peroxide was not effective at the low levels studied. Higher concentrations of hydrogen peroxide that were effective in reducing the bacterial population persisted in the food for more than 4 weeks. Heat-pasteurization in the presence of hydrogen peroxide, was very efficient in destroying bacterial cells and hastened the disappearance of hydrogen peroxide residues from the food. “Labneh”, which is usually prepared from yogurt by filtering out the whey through a cloth, had an inferior texture when prepared from pasteurized yogurt. Milder heat treatment in the presence of hydrogen peroxide and addition of potassium sorbate and thickeners, greatly improved the quality and the shelf-life of labneh as confirmed by sensory evaluation experiments. Further improvements were possible by preparing labneh using centrifugation at various speeds for a short time.

scholarly journals Effects of Additive β-Cyclodextrin on the Performances of Green Tea Infusion

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Qianying Dai ◽  
Sitong Liu ◽  
Huozhu Jin ◽  
Yurong Jiang ◽  
Tao Xia
Keyword(s):  
Green Tea ◽  
Camellia Sinensis ◽  
Oxygen Solubility ◽  
High Quality ◽  
Tea Infusion ◽  
Color Quality ◽  
Tea Infusions ◽  
Conventional Extraction ◽  
Solubility Ratio

The effects of the added β-cyclodextrin (β-CD) in the tea infusion extraction on color quality of green tea (Camellia sinensis) infusion have been investigated in detail. Due to the added β-CD, the color of the tea infusion can be brightened effectively, and meanwhile, compared to conventional extraction, the retentions of tea polyphenols, catechins, and chlorophyll have also been proved to be increased greatly. Furthermore, the additive β-CD can also increase the viscosity of the tea infusion. In addition, the existing β-CD can lower the oxygen solubility ratio in tea infusions effectively, from which a high-quality tea infusion can be prepared ready for further processing.

Decomposition of hydrogen peroxide on cerium dioxide-nickel oxide two-component catalysts and the effect of ionizing radiation on them

1984 ◽  
Vol 49 (1) ◽  
pp. 14-24 ◽  
Author(s):  
Viliam Múčka
Keyword(s):  
Heat Treatment ◽  
Hydrogen Peroxide ◽  
Ionizing Radiation ◽  
Nickel Oxide ◽  
Cerium Dioxide ◽  
Catalytic Properties ◽  
Specific Activity ◽  
Ion Pairs ◽  
Composition Region ◽  
Two Component

Some physical and catalytic properties of cerium dioxide-nickel oxide two-component catalysts have been studied over the entire composition region, employing the decomposition of hydrogen peroxide in aqueous solution as a model catalytic process. The two oxides have been found to affect each other, particularly for NiO contents of 9.1 and 96.7 mol%; the mutual influencing, the nature of which in the conditions applied remains unaffected by heat treatment of the sample or by its exposition to ionizing radiation, is manifested by the nonmonotonic dependences of the oxidation power and of the specific activity of the catalysts on their composition. This can be interpreted in terms of the concept of bivalent catalytic centres, assuming that for nickel oxide the centres consist of Ni2+-Ni3+ ion pairs, for cerium dioxide they consist of Ce3+-Ce4+ ion pairs, and that in the region of the mutual influencing , Ni2+-Ce4+ ion pairs play a major role. Within the scope of this concept, the increase in the oxidation power of all the catalysts in question and a simultaneously decrease in the specific activity of the pure nickeloxide exposed to ionizing radiation can be explained in terms of the ionization effect.

scholarly journals Photocatalytic Production of Hydrogen Peroxide over Modified Semiconductor Materials: A Minireview

2020 ◽  
Vol 63 (9-10) ◽  
pp. 895-912
Author(s):  
Haiyan Song ◽  
Lishan Wei ◽  
Luning Chen ◽  
Han Zhang ◽  
Ji Su
Keyword(s):  
Hydrogen Peroxide ◽  
Semiconductor Materials ◽  
Production Of Hydrogen
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