Thermal Effects on the Stability and Antioxidant Activity of an Acid Polysaccharide Conjugate Derived from Green Tea

Peel off mask has been very popular and preferred due to its ease in application. Gel base has been preferred for its cold and moist sensation during application. When herbal ingredients such as extract is introduced into gel formulation, the stability then will become an issue. The aim of the study was to formulate the peel-off mask gels containing green tea leaves extract (Camellia sinensis L.) which effective, stable, and safe to be used. The antioxidant study was conducted by using Diphenylhydrazylpicryl (DPPH) method. The peel-off mask gel formula were Hidroxypropyl Methylcelulosa (HPMC) as gel base at 0.5% concentration and plasticizer Polyvinyl Alcohol (PVA) at concentration of 12%. Evaluation of peel-off mask gel included observation on pH, viscosity, dispersing power, and drying time during the 90 days of storage at room temperature. The IC50 values of the green tea (Camellia sinensis L.) extract was 5.511 ppm. The concentration of green tea leaves extract in the preparation were 1x IC50 (F1); 2x IC50 (F2) and 3x IC50 (F3). The result showed that all preparations were stable in the aspect of consistency, color, and odor. Viscosity, drying time and dispersing power remained unchanged after 90 days of storage. The pH value changed, but still in the range of acceptable pH of topical preparations. The results of antioxidant activity study showed that formula F3 (peel-off mask gels with 3 x IC50 of green tea extracts) had the highest antioxidant activity.Keywords: antioxidant, Camellia sinensis L., peel off gel masks, green tea

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Uji Aktivitas Antioksidan Sediaan Masker Hidrogel Ekstrak Etanol Teh Hijau (Camellia sinensis) Dengan Metode BCB

Prosiding Seminar Nasional Kesehatan ◽

10.48144/prosiding.v1i.793 ◽

2021 ◽

Vol 1 ◽

pp. 1059-1070

Author(s):

Asri Septiani ◽

W Wirasti ◽

S Slamet ◽

Urmatul Waznah

Keyword(s):

Antioxidant Activity ◽

Green Tea ◽

Camellia Sinensis ◽

Color Change ◽

Ethanol Extract ◽

Test Method ◽

Stability Test ◽

Cycling Test ◽

The Stability ◽

Β Carotene

AbstractGreen tea is a plant that contains antioxidants. The content of green tea compounds that act as antioxidants are polyphenols. The addition of natural antioxidants in hydrogel masks has the potential as an alternative to synthetic antioxidants. The purpose of this study was to determine the antioxidant activity of the hydrogel mask preparation of green tea (Camellia sinensis L.) ethanol extract. The method of determining antioxidant activity was carried out by the -Carotene Bleaching (BCB) method. The stability test of the preparation using the cycling test method was carried out for 6 cycles including organoleptic, viscosity, pH, homogeneity tests. The data obtained from the antioxidant activity test is the IC50 value. The IC50 results of the green tea ethanol extract were 27,162 ppm, while the IC50 values for the formulations 1, 2 and 3 were 40,893 ppm, respectively; 35,348 ppm; and 32,270 ppm. The results of the stability test showed that the preparation was stable from the parameters of viscosity, pH and homogeneity but not stable from the organoleptic parameters because there was a color change in the preparation containing the extract after the cycling test process. In conclusion, both extracts and hydrogel mask preparations contain high antioxidants with relatively stable dosage forms.Keywords: Green Tea, Antioxidants, Hydrogel Mask, -Carotene Bleaching (BCB), IC50. AbstrakTeh hijau merupakan salah satu tanaman yang mengandung antioksidan. Kandungan senyawa teh hijau yang berperan sebagai antioksidan adalah polifenol. Penambahan antioksidan alami pada masker hidrogel berpotensi sebagai alternatif pengganti antioksidan sintetis. Tujuan penelitian ini adalah mengetahui aktivitas antioksidan sediaan masker hidrogel ekstrak etanol teh hijau (Camellia sinensis L.). Metode penentuan aktivitas antioksidan dilakukan dengan metode β-Carotene Bleaching (BCB). Pengujian stabilitas sediaan dengan metode cycling test dilakukan sebanyak 6 siklus meliputi uji organoleptik, viskositas, pH, homogenitas. Data yang diperoleh dari uji aktivitas antioksidan berupa nilai IC50. Hasil IC50 ekstrak etanol teh hijau sebesar 27,162 ppm, sedangkan pada sediaan menunjukan nilai IC50 berturut-turut dari formulasi 1, 2 dan 3 sebesar 40,893 ppm; 35,348 ppm; dan 32,270 ppm. Hasil uji stabilitas menunjukkan sediaan stabil dari parameter viskositas, pH dan homogenitas tetapi tidak stabil dari parameter organoleptik karena terjadi perubahan warna pada sediaan yang mengandung ekstrak setelah proses cycling test. Kesimpulannya ekstrak maupun sediaan masker hidrogel mengandung antioksidan tinggi dengan bentuk sediaan relatif stabil.Kata kunci:Teh Hijau; Antioksidan; Masker Hidrogel; β-Carotene Bleaching (BCB);IC50.

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Physiochemical Characteristics and Antioxidant Activity of Jellies Added with Green Tea Woojeon

The Korean Tea Society ◽

10.29225/jkts.2018.24.2.69 ◽

2018 ◽

Vol 24 (2) ◽

pp. 69-75

Author(s):

Hyeon Jae Yoo ◽

◽

Ha Sook Chung ◽

Keyword(s):

Antioxidant Activity ◽

Green Tea

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Ginger (Zingiber Officinale) Decreases Antioxidant Activity of Black and Green Tea

Current Nutrition & Food Science ◽

10.2174/1573401313666170928144320 ◽

2019 ◽

Vol 14 (5) ◽

pp. 386-390

Author(s):

Javad Aliakbarlu ◽

Surur K. Sadaghiani ◽

Shadieh Mohammadi

Keyword(s):

Antioxidant Activity ◽

Green Tea ◽

Zingiber Officinale

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METHODS FOR RESTORING WOLVES OF ROLLING PRODUCTION

Tekhnicheskiy servis mashin ◽

10.22314/2618-8287-2020-58-4-114-122 ◽

2020 ◽

Vol 4 (141) ◽

pp. 114-122

Author(s):

DAR’YA LEBEDEVA ◽

◽

ANNA KARPUNICHEVA

Keyword(s):

Thermal Effects ◽

Machine Building ◽

Research Purpose ◽

Technical Literature ◽

Production Methods ◽

Advantages And Disadvantages ◽

Rolling Production ◽

Machine Parts ◽

The Stability ◽

High Degree

Large forces and significant thermal effects are created on the rolls when rolling sheets. The higher the stability of the rolls, the less downtime during their rerolling and higher productivity. (Research purpose) The research purpose is in analyzing the ways of restoring rolls and choose the most appropriate method for restoring these parts. (Materials and methods) The article presents the analysis of the scientific and technical literature on the topic of rolling production, methods for restoring large-sized machine parts of machine-building and metallurgical industries that work in difficult conditions and are subject to a high degree of wear. Authors try to solve the problem by means of comparative and logical analysis based on theoretical and empirical methods of scientific research. (Results and discussion) The article presents two groups of methods for restoring rolled rolls: banding and surfacing the working layer of the roll. Authors have analyzed each method in terms of technology, equipment, and feasibility. The article presents the advantages and disadvantages of the methods under consideration. (Conclusions) The most acceptable way to restore parts with a high degree of wear is surfacing. It is most efficient to apply submerged surfacing using an additional hot additive. Such surfacing, despite some complication of the equipment design, allows to deposit the metal on the roll with low heat input and in most cases in one pass. Surfacing using an additional hot additive allows to increase the productivity of the process by up to 250 percent while reducing the penetration depth by 2-3 times and saving energy by up to 40 percent.

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Radix Pseudostellariae protein-curcumin nanocomplex: Improvement on the stability, cellular uptake and antioxidant activity of curcumin

Food and Chemical Toxicology ◽

10.1016/j.fct.2021.112110 ◽

2021 ◽

Vol 151 ◽

pp. 112110

Author(s):

Xixi Cai ◽

Qingxia Weng ◽

Jiaming Lin ◽

Guiqing Chen ◽

Shaoyun Wang

Keyword(s):

Antioxidant Activity ◽

Cellular Uptake ◽

The Stability

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Research perspectives and further studies on catalyst effects on the stability of different polyethylenes during multiple extrusion: Inter‐relationship of oxidation chemistry and antioxidant activity

Journal of Vinyl and Additive Technology ◽

10.1002/vnl.21829 ◽

2021 ◽

Author(s):

Norman S. Allen ◽

Christopher M. Liauw ◽

Michele Edge ◽

Eric Hoang ◽

Eusebio Fontan

Keyword(s):

Antioxidant Activity ◽

Research Perspectives ◽

The Stability ◽

Oxidation Chemistry ◽

Relationship Of

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Effect of food processing on the antioxidant activity of flavones from Polygonatum odoratum (Mill.) Druce

Open Life Sciences ◽

10.1515/biol-2021-0010 ◽

2021 ◽

Vol 16 (1) ◽

pp. 92-101

Author(s):

Guanghui Xia ◽

Xinhua Li ◽

Zhen Zhang ◽

Yuhang Jiang

Keyword(s):

Antioxidant Activity ◽

High Pressure ◽

Food Processing ◽

Yeast Fermentation ◽

Pressure Treatment ◽

Processing Methods ◽

High Pressure Treatment ◽

Effect Of Food ◽

The Stability

Abstract Polygonatum odoratum (Mill.) Druce (POD) is a natural plant widely used for food and medicine, thanks to its rich content of a strong antioxidant agent called homoisoflavones. However, food processing methods could affect the stability of POD flavones, resulting in changes to their antioxidant activity. This study attempts to evaluate the antioxidant activity of POD flavones subject to different processing methods and determines which method could preserve the antioxidant activity of POD flavones. Therefore, flavones were extracted from POD samples, which had been treated separately with one of the four processing methods: extrusion, baking, high-pressure treatment, and yeast fermentation. After that, the antioxidant activity of the flavones was subject to in vivo tests in zebrafish embryos. The results show that yeast fermentation had the least disruption to the antioxidant activity of POD flavones, making it the most suitable food processing method for POD. By contrast, extrusion and high-pressure treatment both slightly weakened the antioxidant activity of the flavones and should be avoided in food processing. The research results provide a reference for the development and utilization of POD and the protection of its biological activity.

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Complexes of Copper and Iron with Pyridoxamine, Ascorbic Acid, and a Model Amadori Compound: Exploring Pyridoxamine’s Secondary Antioxidant Activity

Antioxidants ◽

10.3390/antiox10020208 ◽

2021 ◽

Vol 10 (2) ◽

pp. 208

Author(s):

Guillermo García-Díez ◽

Roger Monreal-Corona ◽

Nelaine Mora-Diez

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Rate Constant ◽

Stable Complex ◽

Aqueous Environment ◽

Oh Radicals ◽

Bidentate Ligands ◽

Superoxide Radical Anion ◽

Amadori Compound ◽

The Stability

The thermodynamic stability of 11 complexes of Cu(II) and 26 complexes of Fe(III) is studied, comprising the ligands pyridoxamine (PM), ascorbic acid (ASC), and a model Amadori compound (AMD). In addition, the secondary antioxidant activity of PM is analyzed when chelating both Cu(II) and Fe(III), relative to the rate constant of the first step of the Haber-Weiss cycle, in the presence of the superoxide radical anion (O2•−) or ascorbate (ASC−). Calculations are performed at the M05(SMD)/6-311+G(d,p) level of theory. The aqueous environment is modeled by making use of the SMD solvation method in all calculations. This level of theory accurately reproduces the experimental data available. When put in perspective with the stability of various complexes of aminoguanidine (AG) (which we have previously studied), the following stability trends can be found for the Cu(II) and Fe(III) complexes, respectively: ASC < AG < AMD < PM and AG < ASC < AMD < PM. The most stable complex of Cu(II) with PM (with two bidentate ligands) presents a ΔGf0 value of −35.8 kcal/mol, whereas the Fe(III) complex with the highest stability (with three bidentate ligands) possesses a ΔGf0 of −58.9 kcal/mol. These complexes can significantly reduce the rate constant of the first step of the Haber-Weiss cycle with both O2•− and ASC−. In the case of the copper-containing reaction, the rates are reduced up to 9.70 × 103 and 4.09 × 1013 times, respectively. With iron, the rates become 1.78 × 103 and 4.45 × 1015 times smaller, respectively. Thus, PM presents significant secondary antioxidant activity since it is able to inhibit the production of ·OH radicals. This work concludes a series of studies on secondary antioxidant activity and allows potentially new glycation inhibitors to be investigated and compared relative to both PM and AG.

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