scholarly journals Functionality changes of natural antioxidants during food processing and storage

2004 ◽  
Vol 22 (SI - Chem. Reactions in Foods V) ◽  
pp. S80-S83 ◽  
Author(s):  
J. Pokorný ◽  
Š. Schmidt ◽  
H. T T Nguyen

Food raw materials and products contain inhibitors of oxidation reactions, both in the lipidic phase and the aqueous phase. The most important inhibitors are phenolic antioxidants. During food processing and storage, concentrations of antioxidants in the two phases reach an equilibrium. Phenolics react with lipidic free radicals, being converted into antioxidant free radicals, quinones, polymers and copolymers. Some degradation products possess an antioxidant activity, too. The relative antioxidant activity decreases with decreasing concentration of oxygen in the system and with increasing temperature. Antioxidants are more rapidly decomposed in surface layers. Health aspects of antioxidant degradation products are often neglected as the safety of antioxidant degradation products is mostly unknown.

Author(s):  
Pozdnyakovа Т.А. ◽  
Kuleshovа Е.S. ◽  
Bubenchikov R.A.

The predominance of synthetic and genetically modified foods in the diet of a modern person often leads to disruption of natural metabolic processes and the accumulation of toxic free radicals in the body, which provokes the development of various diseases. Natural antioxidants from medicinal plants can help maintain health and stop the processes of peroxidation. In our opinion, Аstragalus onobrychis can become a promising source of natural antioxidants. The aim of this study was to establish the antioxidant activity in extracts from the herb Astragalus onobrychis. In order to obtain objective and reliable results during our research, we used two methods: the method of titrimetry and spectrophotometry of free radicals. The titrimetric method is based on the chemical interaction between an oxidizing agent (potassium permanganate) and natural antioxidants present in extracts from plant raw materials, since they exhibit the properties of reducing agents. The spectrophotometric method makes it possible to assess the value of antioxidant activity and the duration of the reaction by assessing the interaction of 2,2-diphenyl-1-picrylhydrazil with plant antioxidants. To establish the relationship between the antioxidant activity and the presence of phenolic compounds in the plant, the content of flavonoids and hydroxycinnamic acids in the herb Astragalus onobrychis was determined. As a result of the studies, the total antioxidant activity of extracts from the herb Astragalus onobrychis was established and it was revealed that its value depends on the type of extractant used, since this factor is associated with the content of various groups of natural antioxidants in the extraction. The data obtained indicate the prospects of using the herb Astragalus onobrychis as a source of natural antioxidants.


Antioxidants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 815 ◽  
Author(s):  
Paulo E. S. Munekata ◽  
Beatriz Gullón ◽  
Mirian Pateiro ◽  
Igor Tomasevic ◽  
Ruben Domínguez ◽  
...  

The use of synthetic antioxidants in the food industry has raised important questions about the effects of prolonged consumption on human health. On top of that, the consumption of meat products has been changing due to the awareness generated by health-related organizations. In this sense, exploring strategies to develop and produce healthier meat products has become a paramount concern. Several studies explored the composition of several seeds to characterize and explore the compounds with antioxidant activity, which are mainly composed of polyphenols. The use of antioxidant extracts in meat products has shown important results to delay the oxidative reactions in meat products derived from the processing and storage of meat products. Moreover, these extracts can also replace synthetic antioxidants and preserve the quality of meat products. Therefore, the aims of this review are first, to present the sources and compounds with antioxidant activity in seeds, and second, to discuss their protective effect against oxidative reactions in meat products.


2019 ◽  
Vol 19 (1-2) ◽  
pp. 27-32
Author(s):  
T. A Pozdnyakova ◽  
R. A Bubenchikov

Topicality. In the process of originating and development of many diseases, an important role belongs to free radicals, which trigger chain reactions leading to damage of cells and tissues. The natural antioxidants can help to neutralize free radicals, among which phenolic compounds are the most active. The presence of these groups of biologically active substances in the herb Astragalus glycyphyllus L. suggests the presence of antioxidant activity in the phyto-complexes of the studied plant. The purpose of this research was to study the antioxidant activity of extracts from the herb Astragalus glycyphyllus L. Materials and methods. The object of the study was the air-dry herb Astragalus glycyphyllus L. harvested in the period of mass flowering. To obtain the most reliable results of the study, the investugation of the antioxidant activity of extracts from the herb Astragalus glycyphyllus L. was carried out by two met hods: by the method based on the chemical reaction between potassium permanganate and regenerating biologically active substances contained in extracts from the studied plant and by spectrophotometry of free radicals based on the reaction interactions of 2,2-diphenyl-1-picrylhydrazyl with antioxidants contained in plant raw materials. To establish the dependence between the antioxidant activity and the presence of phenolic compounds in the plant, the content of flavonoids and hydroxycinnamic acids in Astragalus glycyphyllus L. was determined. Results. It was found that all the studied extracts from the herb Astragalus glycyphyllus L. have antioxidant activity, but their values are different depending on the used extractant. In this case, a consistent pattern is observed between the content in the extraction of phenolic compounds (hydroxycinnamic acids and flavonoids) and the magnitude of antioxidant activity. Conclusions. As a result of the conducted research, the total antioxidant activity of extracts from the herb Astragalus glycyphyllus L. was established. Its value was found to be related to the content of phenolic compounds in the plant by a positive correlation. The obtained data indicate the promising use of the herb Astragalus glycyphyllus L. as a source of natural antioxidants. · Keywords: Astragalus glycyphyllus L.; antioxidant activity; flavonoids; hydroxycinnamic acids; free radicals.


2005 ◽  
Vol 8 (4) ◽  
pp. 413-422 ◽  
Author(s):  
S. Xianquan ◽  
J. Shi ◽  
Y. Kakuda ◽  
J. Yueming

PHARMACON ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 419
Author(s):  
Samuel I.M. Sibarani ◽  
Adithya Yudistira ◽  
Deby A. Mpila

ABSTRACTHabitat of sponge Stylissa sp., were under the sea and these sponges contain active compounds, which are more active than the compounds produced by terrestrial plants. Antioxidants are inhibitors of oxidation reactions due to the free radicals, which can cause weak damage to unsaturated cells, cell wall membranes, blood vessels, DNA bases, and lipid tissue, that causing disease. The study was conducted to determine the antioxidant activity of ethanol extracts  of sponge Stylissa sp., which is located on the Bangka Island, Likupang District, North Minahasa Regency. Sponge Stylissa sp., was extracted by maceration with using ethanol. Testing of antioxidant activity was carried out by the DPPH method measured by a UV-Vis spectrophotometer. The results of the study showed that ethanol extracts of sponge Stylissa sp., has antioxidant activity in each concentration and the highest at a concentration of 100 mg / L. The conclusion is a ethanol extract of sponge Stylissa sp. have high antioxidant activity with a concentration of 25 mg/L (77,40%), concentration of 50 mg/L (85,63%), concentration of 75 mg/L (88,66%), and concentration 100 mg/L (88,96%). Key words: Stylissa sp. Sponge, Antioxidant, DPPH (1,1-diphenyl-2-picrylhydrazyl) ABSTRAKHabitat dari spons Stylissa sp. terdapat di bawah laut dan spons ini mengandung senyawa aktif yang persentase keaktifannya lebih besar dibandingkan dengan senyawa-senyawa yang dihasilkan oleh tumbuhan darat. Antioksidan adalah zat penghambat reaksi oksidasi akibat radikal bebas yang dapat menyebabkan kerusakan lemah tak jenuh, membran dinding sel, pembuluh darah, basa DNA, dan jaringan lipid sehingga menimbulkan penyakit. Penelitian dilakukan untuk mengetahui aktivitas antioksidan ekstrak etanol biota laut spons Stylissa sp. yang terdapat di pulau Bangka, Kecamatan Likupang, Kabupaten Minahasa Utara. Spons Stylissa sp. ini diekstrak dengan metode maserasi menggunakan etanol. Pengujian aktivitas antioksidan ini dilakukan dengan metode DPPH yang diukur dengan alat spektrofotometer UV-Vis. Hasil dari penelitian menunjukan bahwa ekstrak etanol spons Stylissa sp. memiliki aktivitas antioksidan disetiap konsentrasi dan yang tertinggi pada konsentrasi 100 mg/L. Kesimpulan yang didapat bahwa ekstrak etanol spons Stylissa sp. memiliki aktivitas antioksidan yang tinggi dengan konsentrasi 25 mg/L (77,40%), konsentrasi 50 mg/L (85,63%), konsentrasi 75 mg/L (88,66%), dan konsentrasi 100 mg/L (88,96%). Kata Kunci : Spons Stylissa sp., Antioksidan, DPPH (1,1-difenil-2-pikrilhidrazil)


2020 ◽  
Vol 11 (1) ◽  
pp. 1-27
Author(s):  
Adil Hussain

Background: There exist natural antioxidants in plants that scavenge harmful free radicals from the body. Free radicals are species of chemical origin with an unpaired electron and play a pivotal role in combating against health-related problems like lung damage, inflammation, and cardiovascular ailments etc. Antioxidants halt the development of these free radicals called the reactive oxygen species either by chelating the trace elements or by enzymes inhibition. Objectives: The aim of present review was to collect information about Pakistani medicinally important plants with the exploration of their antioxidant potential. Methodology: Total 206 papers were looked over, which were obtained from numerous sources like; Google Scholar, Medline, PubMed, Research Gate, Science Direct, Scopus and Web of Science. Results: Overall, 93 plants representing 44 families with potential antioxidant activity reported from Pakistan have been presented in this review. Maximum number of species from Asteracea, Poaceae and Rutaceae familes were scrutinized for their potential antioxidant activity from Pakistan. Conclusion: The present review clearly designates that the presence of phytochemicals and antioxidant activity of medicinal plants from Pakistan vary with the species of the plants and material/extracts used. From this review, it is recommended to perform comprehensive experimental investigations based on toxicology and ethnopharmacology on these precious plants from Pakistan. It will be advantageous in the provision of trustworthy information to patients and determine further innovative compounds for safer and new drugs development with fewer side effects.


Biomolecules ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 400 ◽  
Author(s):  
Alvaro Martinez-Gomez ◽  
Isabel Caballero ◽  
Carlos A. Blanco

Beer is one of the most consumed drinks around the world, containing a variety of compounds that offer both appreciated sensorial characteristics and health advantages. Important healthy compounds in beer are those with antioxidant properties that attenuate the content of free radicals produced as by-products in the human metabolism, exerting an appreciable effect against cancers or cardiovascular diseases. This work details a study of antioxidant compounds present in beer, focusing on the two main groups: phenols (including polyphenolic forms) and melanoidins, formed specifically during brewing as Maillard products. The fundaments of the most important methods to evaluate beer antioxidant activity, the main antioxidant compounds present in beer—especially those with healthy properties—and the new trends to increase beer antioxidant activity are also discussed.


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