scholarly journals SINTESIS SENYAWA KALKON SERTA UJI AKTIVITAS SEBAGAI ANTIOKSIDAN

Jurnal Kimia ◽  
2016 ◽  
Author(s):  
I Wayan Suirta

Synthesis chalcone compound by reaction between acetofenone and benzaldehyde using natrium hydroxide as catalyst with distil water or ethanol as solvent has been done. The yield was determined using antioxidant activity test with DPPH and GC-MS. The result of synthesis was pale yellow crystal with melting point of 55-570C. The synthesis in distil water yielded 84,98 %, and the formation of crystal was about 1 hour. The synthesis in ethanol resulted 87,68% yield, with the formation of crystal about 15 minutes. The product showed weak antioxidant activity with reduction percentage averaged at 50%. The GC-MS showed the presence of chalcone compound with sufficiently high purity.

2019 ◽  
Vol 5 (3) ◽  
pp. 11-20
Author(s):  
Stefani Dhale Rale ◽  
Hasim Hasim ◽  
Syamsul Falah

This study aims to find the treatment of diabetes using natural materials by exploring plants in the province of East Nusa Tenggara. his research was conducted out by extracting the Strychnos nitida G.Don stem using a method of maceration by ethanol 70%. Ethanol extract was then fractionated using n-hexane and ethyl acetate. Simplicia from maceration and fractionation results were then tested for antioxidant activity, α-glucosidase inhibition activity and identification of active compounds. The results showed that ethyl acetate fraction had the lowest IC50 value of 86.83 μg / ml. Results of the α-glucosidase activity test showed that ethyl acetate fraction and n-heksan fraction at 900 ppm had the highest percentage of inhibition of 34.23% and 33.89%. Identification using LCMS/MS method showed that ethyl acetate fraction consist of Benzenemethamine, N, N-dioctyl- as an antioxidantcompound and compound 24-methyl-5-cholestone-hexol as an antidiabetic compound. From the results of this study, we concluded that the extract of kayu ular Strychnos nitida G.Don stem has inhibition activity toward α-glucosidase enzyme.


2020 ◽  
Vol 1 (1) ◽  
pp. 24-31
Author(s):  
Elvi Kustiyah ◽  
Bungaran Saingin ◽  
Hernowo Widodo ◽  
Viriya Piti

 Indonesia has millions island and big part of Indonesia is sea that is rich in marine biological resources and has the potential to be developed and optimized. One of the abundant marine resources in Indonesia is algae. Algae are plant-like protists. Algae have several important compounds, including protein, carbohydrates, fats, minerals and other useful elements. Proteins contained in algae have the potential to be used as antioxidants. In this study, the levels of protein in red and green algae were tested by using the lowry method and testing the antioxidant activity of red and green algae extracts using the Diphenylpicrylhydrazyl (DPPH) method. Algae extraction was done by maceration, which is soaking the sample in low temperature with phosphate buffer saline (PBS) pH 7. From the extraction results it can be concluded that the red algae (Rhodophyta) has the highest protein content of 5.115 ± 0.126% and the lowest protein content in green algae (Chloropytha) as big as 1.686 ± 0.430%. And from the results of the antioxidant activity test showed that all positive algae showed antioxidant activity but the green algae (Chlorophyta) had the highest antioxidant activity of 71.5946 ± 0.01612% with IC50 value 1.6114.


1907 ◽  
Vol 27 ◽  
pp. 308-311 ◽  
Author(s):  
Alexander Smith ◽  
R. H. Brownlee

AbstractIn papers previously read before the Society, the behaviour of sulphur when heated has been the subject of investigation. It has been shown that the transition from a pale-yellow mobile liquid to a deep-brown viscous one, which occurs as the temperature rises in the neighbourhood of 160°, is due to the production from the mobile sulphur (Sλ) of another distinct variety (Sμ). The proportion of the viscous variety (Sμ) is about 4 per cent, at the melting point (114·5°). At 160° it has become 11 per cent., at 170° 19 per cent., and at the boiling point 34 per cent.


2021 ◽  
Vol 5 (01) ◽  
pp. 36-44
Author(s):  
Babita Adhikari ◽  
Shonu Rai

Phytate and tannin are more pronounced antinutrients limiting the nutritional quality of fenugreek. The impact of roasting (130±5°C for 7 minutes), soaking (12 hrs. at room temperature) and germination (72 hrs. at 25°C) on bioactive compounds (polyphenol and antioxidant activity), nutritional and anti-nutritional compounds (phytate and tannin) in Fenugreek were studied. Experimental data were analyzed using the software GenStat 12th Edition. Protein increased significantly (p<0.05) during roasting, soaking, and germination whereas fat decreased significantly. Iron and calcium increased during roasting whereas decreased during soaking and germination. Maximum reduction of phytate (54.55%) and tannin (66.73%) were found when fenugreek seeds were germinated (72 hours). The reduction percentage of antinutrients by soaking (12 hours) and roasting (130±5⁰C for 7 mins) was found to be a lesser effective method compared to germination. All the treatments had a significant (p<0.05) impact on their bioactive components. Phenolic content increased significantly (p<0.05) during roasting, soaking, and germination. Antioxidant activity (IC50=1.28mg dm/ml) was found to be high in the germinated samples as compared to raw, roasted, and soaked samples. Hence, Germination of fenugreek seeds for 72 hours is concluded as the most effective and promising method for the reduction of antinutrients and increasing the nutritional components, phytochemicals, and antioxidant properties.


Author(s):  
Asriullah Jabbar ◽  
Wahyuni Wahyuni ◽  
Muh Hajrul Malaka ◽  
Apriliani Apriliani

Wualae (Etlingera elatior (Jack) R.M Smith) is one of the plants in the Zingiberaceae family, widely used in medicine ranging from rhizomes, fruits, and flowers. Empirically Wualae are usually used by people for treating skin diseases, flavoring food, a natural soap, and in Southeast Sulawesi, it is used to treat typhoid fever. This study aims to examine the antioxidant activity of Wualae (Etlingera elatior) plant. The plant extracts were extracted by maceration method, antioxidant activity test was performed by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method. The results showed that ethanol extracts of fruits, leaves, stems and rhizomes of Wualae (Etlingera elatior) has the potential antioxidant activity with the IC50 values of 72.518 mg/L, 99.890 mg/L, 52.345 mg/L and 58.638 mg/L, respectively. and Vitamin C has IC50 value of 3,787 mg/L.


2017 ◽  
Vol 9 (1) ◽  
pp. 79
Author(s):  
Sri Wahdaningsih ◽  
Subagus Wahyuono ◽  
Sugeng Riyanto ◽  
Retno Murwanti

<p> </p><p>Red dragon fruit (<em>H. Polyrhizus</em>) is one of the the plants that has a great potential as natural antioxidant. This study tested the activity of radical scavenging of 2-2' diphenyl -1- pikril hidrazil (DPPH) in the methanol extract, as well as in the soluble and insoluble fractions of ethyl acetate of red dragon fruit peel. This research is carried out through various stages, such as: extraction and fractionation to obtain both insoluble fraction and soluble fractions of ethyl acetate. Antioxidant activity test is conducted by the method of thin layer chromatography and spectrophotometry.<strong> </strong>Antioxidant activity test, IC<sub>50 </sub>values of methanol extract, ethyl acetate soluble fraction, and insoluble fraction of ethyl acetate had been obtained consecutively as much as 241.19 µg /mL, 8.34  µg/mL, 46.84 µg/mL. The soluble fraction of ethyl acetate had greater antioxidant activity compared to the methanol extract and the insoluble fractions of ethyl acetate.</p>


PHARMACON ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 178
Author(s):  
Julia Elsa Lakoro ◽  
Max R. J. Runtuwene ◽  
Paulina V. Y. Yamlean

ABSTRACTNanamuha (Bridelia monoica Merr.) is a plant that was used as a cancer and tumor drug by the Sangihe Islands community. This plant contains phenol compounds, flavonoids, alkaloids and tannins. The purpose of this study was to determine the potential of nanamuha leaves that grow in the Sangihe Island to have antioxidant activity and determine the total phenolic ethanol extracts of nanamuha leaf. The extraction method used is maceration with ethanol solvent p.a. The extracts obtained was determined total phenolic and antioxidant activity test using DPPH method. Based on the results obtained, the ethanol extracts of nanamuha leaves has antioxidant activity with an IC50 value of 75,03 µg / mL and the result showed that the total phenol content the ethanol extracts of nanamuha leaves of  53,34 mg / L.  Keywords : Nanamuha leaf, total phenol, antioxidant activity, DPPH  ABSTRAKNanamuha (Bridelia monoica Merr.) merupakan tanaman yang dimanfaatkan sebagai obat kanker dan tumor oleh masyarakat Kepulauan Sangihe. Tanaman ini memiliki kandungan senyawa fenol, flavonoid, alkaloid dan tanin. Tujuan dari penelitian ini adalah unutuk mengetahui potensi dari daun nanamuha yang tumbuh di Kepulaun Sangihe ini memiliki aktivitas antioksidan dan menentukan total fenolik dari ekstrak etanol daun nanamuha. Metode ekstraksi yang digunakan adalah maserasi dengan pelarut etanol p.a. Ekstrak yang diperoleh ditentukan total fenolik dan uji aktivitas antioksidan dengan metode DPPH. Berdasarkan hasil yang didapatkan ekstrak etanol daun nanamuha memiliki aktivitas antioksidan dengan nilai IC50 75,03 µg/mL dan hasil penelitian menunjukan total kandungan fenolik ekstrak etanol daun nanamuha sebesar 53,34 mg/L. Kata kunci : Daun Nanamuha, Total fenol, Aktivitas antioksidan, DPPH


2018 ◽  
Vol 14 (1) ◽  
pp. 107
Author(s):  
Mardiyah Kurniasih ◽  
Purwati Purwati ◽  
Ratna Stia Dewi ◽  
Susi Fatimah

<p>Telah dilakukan uji aktivitas antioksidan dari N-metil kitosan yang memiliki kelarutan tinggi. Uji aktivitas antioksidan dilakukan dengan menggunakan metode DPPH (1,1-diphenyl-2-pikrilhidrazil) dan metode FTC (<em>ferric thiocyanate</em>). Optimasi sintesis dilakukan untuk memperoleh N-metil kitosan dengan kelarutan tinggi. Hasil penelitian menunjukkan bahwa N-metil kitosan yang berkelarutan paling tinggi adalah N-metil kitosan yang disintesis dengan 1,7 mL formaldehid 10%. Berdasarkan hasil uji aktivitas antioksidan menggunakan metode DPPH dapat diketahui bahwa N-metil kitosan merupakan antioksidan sedang dengan nilai IC<sub>50</sub> sebesar 145,398 ppm. Hasil pengujian antioksidan metode FTC menunjukkan bahwa N-metil kitosan memiliki kemampuan menghambat terbentuknya senyawa radikal bebas yang disebabkan oleh oksidasi asam lemak.</p><p><strong>An Antioxidant Activity Test of High Solubility N-Methyl Chitosan</strong><strong>.</strong> An antioxidant activity test of high solubility N-methyl chitosan has been performed. The antioxidant activity test was performed using DPPH (1,1-diphenyl-2-pikrilhidrazil) and FTC method (ferric thiocyanate). The synthesis optimization was performed to obtain high N-methyl chitosan solubility. The results showed that N-methyl chitosan with the highest solubility in 1% acetic acid solvent was N-methyl chitosan which was synthesized with 1.7 mL formaldehyde 10%. Based on the results of antioxant activity test using DPPH method can be seen that N-methyl chitosan is a medium antioxidant with IC<sub>50</sub> value of 145.398 ppm. The result of antioxidant test of FTC method showed that N-methyl chitosan has antioxidant activity with tendency to increase along with the increase of N-methyl chitosan concentration.</p>


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