Enzymatic and Non-Enzymatic Antioxidants in Plants

Year 2018, Volume: 7 Issue: 2, 473 - 483, 28.12.2018

Oğuz Ayhan Kireçci

https://doi.org/10.17798/bitlisfen.463251

Cited By: 1

Abstract

Living
things have defense mechanisms against environmental stresses. These mechanisms
protect the organism against adverse effects of stress conditions. Stress
responses are a complex process. Live systems can survive according to the
compatibility of their responses to stress types. Antioxidant defense is the
most important mechanism to combat stress in biological systems. As in animals,
there is antioxidant defense in plants. It is difficult to clarify biological
stress responses such as plants. Plants can fight against the negative effects
of environmental stress through their antioxidant systems. The antioxidant
system consists of enzymatic antioxidants such as Superoxide dismutase,
Catalase, Ascorbate peroxidase, Glutathione peroxidase, Glutathione reductase,
Dehydroaskorbate reductase, Monodehydroaskorbate reductase and Guaiacol
peroxidase, as well as non-enzymatic antioxidants such as Ascorbic acid, Glutathione,
α-Tocopherol, Carotenoid and Phenolic compounds. This review, plants' enzymatic
and non-enzymatic antioxidants were explained and it was intended to provide
contribution to literature.

Keywords

Antioxidant system, Enzymatic antioxidant, Non-enzymatic antioxidant, Plant, Stress

Bitkilerde Enzimatik ve Enzimatik Olmayan Antioksidanlar

Abstract

Canlılar çevresel streslere karşı
savunma mekanizmalarına sahiptir. Bu mekanizmalar canlıyı stres şartlarının olumsuz
etkilere karşı korur. Stres cevaplarının oluşması karmaşık bir süreçtir. Canlı
sistemler stres tiplerine karşı oluşturdukları yanıtların uyumuna göre hayatta
kalmayı başarabilirler. Biyolojik sistemlerde stresle mücadele eden en önemli
mekanizma antioksidan savunmadır. Hayvanlarda olduğu gibi bitkilerde de
antioksdian savunma mevcuttur. Bitkiler gibi biyolojik stres cevaplarını
aydınlığa kavuşturmak zordur.  Bitkiler;
antioksidan sistemleri sayesinde çevresel stresin olumsuz etkilerine karşı
mücadele edebilirler. Antioksidan sistem Süperoksit dismutaz, Katalaz, Askorbat
peroksidaz, Glutatyon peroksidaz, Glutatyon redüktaz, Dehidroaskorbat redüktaz,
Monodehidroaskorbat redüktaz ve Guaiakol peroksidaz gibi enzimler ile Askorbik
asit, Glutatyon, α –Tokoferol, Karotenoid ve Fenolik bileşikler gibi enzimatik
olmayan antioksidanlardan oluşur. Bu derlemede bitkilerde mevcut olan enzimatik
ve enzimatik olmayan antioksidanlar açıklanmış ve literatüre katkı amaçlanmıştır.

Keywords

Antioksidan sistem, Bitki, Enzimatik antioksidan, Enzimatik olmayan antioksidan, Stres

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