scholarly journals Pengaruh Waktu Aging dan Metode Ekstraksi terhadap Aktivitas Antioksidan Black Garlic yang Dibandingkan dengan Bawang Putih (Allium sativum L.)

2021 ◽  
Vol 1 (1) ◽  
pp. 16-23
Author(s):  
Salma Fadhilah Azhar ◽  
Kiki Mulkiya Y ◽  
Reza Abdul Kodir
Keyword(s):  
Free Radical ◽  
Chemical Reactions ◽  
Maillard Reaction ◽  
Oxidation Reaction ◽  
Aging Process ◽  
Room Temperature ◽  
Allium Sativum ◽  
Absorbance Measurement ◽  
Activity Test ◽  
Radical Reduction

Abstract. Antioxidant is a compound that could obstruct oxidation reaction through free radical binding. Garlic (Allium sativum L.) is a plant which has many benefits that could be used for traditional medication. Some of pharmacology effects which was discovered are antioxidant, anti-hypertensive, anti-cholesterol, and antimicrobial. Black garlic is the heating aging process which induces many chemical reactions of garlic such as non-enzymatically discoloration to be brown, Maillard reaction which produces antibacterial compound, caramelization, and phenol formation as antioxidant that causes discoloration from cream to dark brown or black. White and Black garlic were extracted through two methods, namely maceration (room temperature) and digestion (± 40°C) by using 96% ethanol solvent. The activity test of extract antioxidant is done using DPPH free radical reduction (2,2-difenil-1-pikrilhidrazil) with absorbance measurement uses UV-Vis spectrophotometry with DPPH maximum wavelength is 515 mm. Garlic maceration has value IC50 in the amount of 28.422 ppm, two weeks maceration of black garlic in the amount of 27.129 ppm and four weeks maceration of black garlic in the amount of 13.041 ppm. While garlic digestion in the amount of 28.524 ppm, two weeks digestion of black garlic in the amount of 28.086 ppm and four weeks digestion of black garlic in the amount of 15.160 ppm. Abstrak. Antioksidan merupakan senyawa yang dapat menghambat reaksi oksidasi, dengan cara mengikat radikal bebas. Bawang putih (Allium sativum L.) merupakan salah satu tanaman yang mempunyai banyak khasiat yang digunakan untuk pengobatan tradisional. Efek farmakologi yang telah diketahui salah satunya adalah antioksidan, anti-hipertensi, anti-kolesterol, anti-mikroba. Bawang hitam merupakan proses aging dengan pemanasan yang menginduksi banyak reaksi kimia pada bawang putih seperti perubahan warna menjadi coklat secara non-enzimatik, reaksi Maillard yang menghasilkan senyawa antibakteri, karamelisasi, dan pembentukan fenol sebagai antioksidan yang menyebabkan warnanya berubah dari putih kekuningan menjadi coklat tua atau hitam. Bawang putih dan bawang hitam diekstraksi menggunakan dua metode yaitu maserasi (suhu kamar) dan digesti (suhu ±40°C) dengan menggunakan pelarut etanol 96%. Uji aktivitas antioksidan ekstrak dilakukan dengan menggunakan metode peredaman radikal bebas DPPH (2,2-difenil-1-pikrilhidrazil) dengan pengukuran absorbansi menggunakan spektrofotometri UV–Vis pada panjang gelombang maksimal DPPH yaitu 515 nm. Pada bawang putih maserasi memiliki nilai IC50 sebesar 28,422 ppm, bawang hitam 2 minggu maserasi 27,129 ppm dan bawang hitam 4 minggu maserasi 13,041 ppm. Sedangkan pada bawang putih digesti 28,524 ppm, bawang hitam 2 minggu digesti 28,086 ppm dan bawang hitam 4 minggu digesti 15,160 ppm.

Reduction of Folate and Dihydrofolate by Dithionite

1972 ◽  
Vol 50 (11) ◽  
pp. 1191-1198 ◽  
Author(s):  
M. Kawai ◽  
K. G. Scrimgeour
Keyword(s):  
Free Radical ◽  
Low Temperatures ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Kinetic Method ◽  
Sodium Dithionite ◽  
Nucleophilic Attack ◽  
Stopped Flow ◽  
Reduction Processes ◽  
Radical Reduction

Sodium dithionite reduces folate to 7,8-dihydrofolate at room temperature, but further reduction to the tetrahydro level can be obtained at elevated temperatures (11). Both folate and dihydrofolate form adducts with dithionite (presumably sulfinates), and these adducts appear to be intermediates in the reduction processes. The adduct of dihydrofolate is not converted to tetrahydrofolate at low temperatures, and is thus more amenable to examination. The mechanism of reduction of the folate compounds and of the nicotinamide ring by dithionite involves nucleophilic attack by the dithionite, not a free radical reduction as with p-nitrophenol. The rate of addition of bisulfite to folate and dihydrofolate has been measured by the stopped-flow kinetic method, and the nonenzymic and enzyme-catalyzed addition of nucleophiles to folate compounds is discussed.

The Microstructure of Diene Polymers. II. Polyisoprenes and Polybutadienes Prepared at High Pressures

1954 ◽  
Vol 27 (4) ◽  
pp. 958-961
Author(s):  
W. S. Richardson
Keyword(s):  
Free Radical ◽  
Hydrostatic Pressure ◽  
Chemical Reactions ◽  
Atmospheric Pressure ◽  
Room Temperature ◽  
High Pressures ◽  
Bulk Polymerization ◽  
Extensive Investigation ◽  
Very High ◽  
Increased Pressure

Abstract The rapid bulk polymerization of isoprene at room temperature under high hydrostatic pressure was apparently first observed by Bridgman and Conant. A more extensive investigation by Conant and Tongberg established the free radical nature of the polymerization (peroxide catalysis and hydroquinone inhibition). The latter workers also noted the solubility and elasticity of polymers made to moderate conversion and the insoluble crumbly nature (gelation) of the polymers made to very high conversion. In view of the well known effect of increased pressure in driving chemical reactions in the direction of the products of least specific volume, it is of interest to consider the possibility that diene polymers made at high pressures may be different in microstructure from polymers made at comparable temperatures but near atmospheric pressure.

EFEKTIVITAS ANTIBAKTERI BAWANG PUTIH (Allium sativum L) SEBAGAI PENGAWET ALAMI PADA IKAN LELE DUMBO (Clarias gariephinus) SEGAR

2019 ◽  
Vol 14 (1) ◽  
pp. 26
Author(s):  
Dyah Anggraeni ◽  
Nurlela Nurlela
Keyword(s):  
Room Temperature ◽  
Allium Sativum ◽  
Research Result ◽  
Clarias Gariepinus ◽  
Storage Period ◽  
The Body ◽  
Garlic Extract ◽  
African Catfish ◽  
Natural Preservatives ◽  
Colony Counter

Background: Natural preservatives are compounds produced by natural ingredients that can suppress bacterial growth and development. Natural preservatives are carried out because most of the preservatives circulating are chemicals and unsafe for the body. One of the natural preservatives is by using garlic extract (Allium sativum L).  Objective: This study is aimed to determine the effectiveness of the antibacterial garlic (Allium sativum L) as a natural preservative in fresh African catfish (Clarias gariepinus).  Method: This research used the Pour Plate iroculation method. African catfish (Clarias gariepinus) which is soaked with garlic (Allium sativum L) with a concentration of 7%, 14% and 21% for 30 minutes, then the fish will be kept at room temperature with a storage period of 24 hours and 48 hours and calculated growth in bacterial numbers with the Colony counter.  Result: Based on the research result, it was found that garlic extract (Allium sativum L) can obstruct the effectiveness of antibacterial in African catfish (Clarias gariepinus) at a concentration of 14%.

scholarly journals THE EFFECT OF CORONA INCANDESCENT PLASMA RADIATION AND STORAGE TEMPERATURE ON THE VIABILITY OF GARLIC SEEDS (ALLIUM SATIVUM L. LUMBU KUNING VARIETY)

2021 ◽  
Vol 5 (1) ◽  
pp. 11-17
Author(s):  
Febiasasti Trias Nugraheni ◽  
Erma Prihastanti ◽  
Endah Dwi Hastuti
Keyword(s):  
Room Temperature ◽  
Allium Sativum ◽  
Storage Temperature ◽  
Germination Percentage ◽  
Plasma Radiation ◽  
Agricultural Commodity ◽  
Time Duration ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
And Storage

Garlic (Allium sativum L.) is an agricultural commodity which is widely consumed by the community. The obstacle experienced in cultivation is that a relatively long dormancy period of about 6-7 months. The dormancy of garlic seeds occurs because the embryo has not yet been fully formed, and the growth hormone and inhibitory hormone are not balanced. The methods used to break dormancy and accelerate germination are by using corona incandescent plasma radiation and storage temperature. The research utilized factorial Completely Randomized Design (CRD), consisting of six treatments with five replications. The first factor was the corona incandescent plasma radiation carried out on the garlic seeds ‘Lumbu Kuning’ variety with time duration of 0, 15, and 30 minutes. The second factor was storage temperature comprising of room temperature and cold temperature of 7oC stored for 30 days. Viability parameters observed are germination percentage dan the length of sprouts. The data were analyzed by using ANOVA followed by the DMRT test at the 95% confidence level. The results showed that corona incandescent plasma radiation influenced the germination percentage using plasma radiation for 15- 30 minutes.

scholarly journals SINTESIS CALKON ((E)-1,3-DI(NAPHTHALEN-2-YL)PROP-2-EN-1-ONE) DAN AKTIVITASNYA SEBAGAI ANTIOKSIDAN

2012 ◽  
Vol 3 (1) ◽  
pp. 7-14
Author(s):  
Rahmiwati Hilma ◽  
Jasril ◽  
Hilwan Yuda Teruna
Keyword(s):  
Free Radical ◽  
Melting Point ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Room Temperature ◽  
Intermediate Compound ◽  
Alkaline Condition ◽  
Point Measurement ◽  
Anti Inflammatory ◽  
Layer Chromatography

Study on chalcone calkon (E)-1,3-di(naphthalen-2-yl)prop-2-en-1-one synthesis have been carried out with stirrer methode. These compounds can be used as intermediate compound to synthesize others compounds which was reported having antimicrobial, anti-inflammatory, anti-depressant, anti-tumour. The of chalcones synthesis vatives were reported in acid and alkali condition. In this study, chalcone and its derivates were synthesized by using stirrer method in alkaline condition in room temperature. the compounds subjected to somes analyses including melting point measurement, thin layer chromatography and HPLC. Scavenging free radical by using DPPH methode showed Scavenging free radical with LC50 >80 μg/ml min potent activity while the ascorbat acid LC50 89,79 μg/ml.

CuWO4 as a photocatalyst for room temperature aerobic benzylamine oxidation

2018 ◽  
Vol 54 (9) ◽  
pp. 1101-1104 ◽  
Author(s):  
Aaron D. Proctor ◽  
Shobhana Panuganti ◽  
Bart M. Bartlett
Keyword(s):  
Oxidative Coupling ◽  
Oxidation Reaction ◽  
Room Temperature ◽  
Photo Oxidation

We report the first example of a controlled photo-oxidation reaction on CuWO4, the aerobic oxidative coupling of benzylamine.

Blue Light Driven Free-Radical Polymerization using Arylazo Sulfones as Initiators

2021 ◽  
Author(s):  
Andrea Nitti ◽  
Angelo Martinelli ◽  
Fabrice Batteux ◽  
Stefano Protti ◽  
Maurizio Fagnoni ◽  
...  
Keyword(s):  
Free Radical ◽  
Visible Light ◽  
Radical Polymerization ◽  
Blue Light ◽  
Room Temperature ◽  
Free Radical Polymerization

The polymerization of a broad range of electron-poor olefins has been achieved under free-radical conditions by using arylazo sulfones as visible light photoinitiators. The process proceeds smoothly at room temperature...

PERBANDINGAN METODE EKSTRAKSI MASERASI DAN SOKLETASI TERHADAP AKTIVITAS ANTIOKSIDAN EKSTRAK ETANOL DAUN JAMBU BOL (Syzygium malaccense L.)

2017 ◽  
Vol 3 (1) ◽  
pp. 91
Author(s):  
Henny Nurhasnawati ◽  
Sukarmi Sukarmi ◽  
Fitri Handayani
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Vitamin C ◽  
Extraction Methods ◽  
Natural Antioxidant ◽  
Comparison Of Methods ◽  
Activity Test ◽  
Ic50 Value ◽  
The Difference ◽  
Free Radical Activity

Malay apple (Syzygium malaccense L.) is a plant that can be used for treatment. Antioxidants have the activity to reduce free radical compounds which is one of the causes of the emergence of various diseases in humans. The purpose of this study to determine the comparison of methods of maceration and socletation extraction of antioxidant activity of malay apple leaf. Research stages include sampling, plant determination, making of simplisia, maceration extraction and socletation with 70% ethanol solvent and determine the antioxidant activity by UV-Vis spectrophotometry with DPPH (1,1-diphenyl-2-picrylhydrazyl) as free radical. The parameter is IC50 value that is the concentration of antioxidant compound which can cause 50% loss of DPPH free radical activity. Although both methods show very strong antioxidant activity, it can be concluded that the difference in extraction methods has an effect on the antioxidant activity produced. The results of antioxidant activity test showed that socletation methods gave an average IC50 value of 37.67 ppm, this value is higher than maceration methods with an average IC50 value of 47.80 ppm. Malay apple leaf has the potential as a natural antioxidant, although it has a lower IC50 value than vitamin C which is 9.72 ppm.

Sign in / Sign up

Export Citation Format

Share Document