Reactive oxygen species (ROS) are a class of highly reactive molecules derived from the metabolism of oxygen. ROS, including superoxide radicals, hydroxyl radical and hydrogen peroxide molecules are often generated as by products of biological reactions or from exogenous factors. There is extensive evidence to involve ROS in the development of degenerative diseases. Evidence suggests that compounds especially from natural sources are capable of providing protection against free radicals. This has attracted a great deal of research interest in natural antioxidants. It is necessary to Screen out medicinal plants for their antioxidant potential. Therefore an attempt has been made to review different in vitro models for estimating antioxidant properties of natural products from medicinal plants. All the models are described along with the different standards that can be used for estimation. In the end, a large number of plants showing in vitro antioxidant activity are listed but in vivostudies are lacking. 

	 

	Key words: Antioxidant assay, in vitro models, antioxidant medicinal plants.

In vitro models for antioxidant activity evaluation and some medicinal plants possessing antioxidant properties: An overview

Edible seaweeds are rich in bioactive antioxidants, soluble dietary fibers, proteins, minerals, vitamins, phytochemicals, and polyunsaturated fatty acids Although previously the seaweeds were only used as gelling and thickening agents in the food or pharmaceutical industries, recent researches have revealed their potential as complementary medicine The red, brown and green seaweeds have been shown to have therapeutic properties for health and disease management, such as anticancer, antiobesity, antidiabetic, antihypertensive, antihyperlipidemic, antioxidant, anticoagulant, anti-inflammatory, immunomodulatory, antiestrogenic, thyroid stimulating, neuroprotective, antiviral, antifungal, antibacterial and tissue healing properties in vivo Active compounds include sulphated polysaccharides, phlorotannins, carotenoids (eg fucoxanthin), minerals, peptides and sulfolipids, with proven benefits against degenerative metabolic diseases Their therapeutic modes of action and bioactive components have been meticulously studied by scientists and their reports are summarized in this review

Seaweeds: A sustainable functional food for complementary and alternative therapy

Free radicals are well documented for playing a dual role in our body as both deleterious and beneficial species. In low/moderate concentrations free radicals are involved in normal physiological functions but excess production of free radicals or decrease in antioxidant level leads to oxidative stress. It is a harmful process that can be mediates damage to cell structures, including lipids, proteins, RNA and DNA which leads to number of diseases. A variety of synthetic medicine employed in the treatment of different diseases also capable to generate free radicals in body which may causes another disease. The plant sources are rich of antioxidants, phyto-constituents are capable to terminate free radical reactions and prevent our body from oxidative damage. Vegetables and fruits are also important sources of antioxidant substances. Different phytoconstituents and herbal product which are safer then synthetic medicine and beneficial in the treatment of diseases caused by free radicals, it also protect the body by prevent the free radicals to cause tissue injury. Phytoconstituents are conferring less side effect and compatible to body physiology. Therefore it is demand of modern era to use such phytoconstituents or phytomedicines.

Free radicals, antioxidants, diseases and phytomedicines: current status and future prospect

Total phenolic contents and free radical scavenging activity of certain Egyptian Ficus species leaf samples

https://digital.csic.es/bitstream/10261/35499/3/Advanced_analysis_of_nutraceuticals_Bernal_2011.pdf

Advanced analysis of nutraceuticals.

Simultaneous quantification of bergenin, catechin, and gallic acid from Bergenia ciliata and Bergenia ligulata by using thin-layer chromatography

Quality is conformance to requirement and meeting stated as well as implied needs of customer. The word quality is derived from Latin ‘qualis’ means ‘of what kind’ and encompasses composition and properties of object. Quality is of paramount importance when it is specifically related with drugs. And when it comes to herbal drugs, because of several reasons is a herculean task. The quality of pharmaceuticals has been a concern of the World Health Organization (WHO) since its inception. The setting of global standards is requested in Article 2 of the WHO Constitution, which cites as one of the Organization’s functions that it should “develop, establish and promote international standards with respect to food, biological, pharmaceutical and similar products”. The World Health Assembly - in resolutions WHA31.33 (1978), WHA40.33 (1987) and WHA42.43 (1989) - has emphasized the need to ensure the quality of medicinal plant products by using modern control techniques and applying suitable standards. This manual describes a series of tests for assessing the quality of medicinal plant materials. The tests are designed primarily for use in national drug quality control laboratories in developing countries, and complement those described in ‘The international pharmacopoeia’ which provides quality specifications only for the few plant materials that are included in the WHO ‘Model List of Essential Drugs'. In this review, we have addressed some important issues related to quality of botanicals and discussed possible application of total quality management for herbal drugs. Keywords: WHO, Herbal Drugs, Quality Control.

https://www.arjournals.org/index.php/ijpm/article/download/23/19

Application of quality control principles to herbal drugs.

Sida cordifolia. Linn. (Malvaceae) is commonly known as bala. and widely used in Ayurveda. The comparative antioxidant potential of ethanol extracts of Sida cordifolia. leaf, stem, root, and whole ...

https://www.tandfonline.com/doi/pdf/10.1080/13880200500406438

Evaluation of the Antioxidant Activity of Sida cordifolia.

Sida rhombifolia (L.) ssp. retusa (L.) is widely used in Ayurvedic medicine for the treatment of fever as well as a diuretic. The comparative antioxidant potentials of ethanol extract of roots, stems, leaves, and whole plant were studied. Estimation of total polyphenolic content and high-performance thin-layer chromatography profile were determined. Further inhibition of oxygen-derived free radicals, viz., assays for free radical scavenging, reducing power, superoxide anion scavenging, nitric oxide scavenging, and anti-lipid peroxidation, were performed. All the antioxidant activities were compared with standard antioxidants such as butylated hydroxyanisole and α-tocopherol acetate. Extracts were found to be good scavengers of the 1,1-diphenyl-2-picrylhydrazyl radical in the order root > leaves > whole plant > stem with 50% inhibitory concentrations of 546.1, 852.8, 983.8, and 1,222.5 μg/mL, respectively. All extracts of this plant showed effective free radical scavenging activity, reducing power, and sup...

Evaluation of In Vitro Antioxidant Activity of Sida rhombifolia (L.) Ssp. retusa (L.)

In the Indian systems of medicine, there are many highly valued medicinal plants. Aegle marmelos. Correa (Rutaceae), commonly known as “bael,” is one of them. Its fruit exhibited antidiabetic, antihyperlipidemic, and antioxidant properties. This study was designed to evaluate in vitro. antioxidant activity of umbelliferone and psoralen in a methanol extract of A. marmelos. fruit pulp. A simple high performance thin layer chromatography (HPTLC) method has been developed for the simultaneous quantification of umbelliferone and psoralen. The method was validated for precision, repeatability, and accuracy in accordance with International Conference on Harmonisation (ICH) guidelines. Inhibition of oxygen-derived free radicals (ODFR), viz.., free radical scavenging, reducing power, superoxide anion scavenging assay, nitric oxide scavenging assay, and anti–lipid peroxidation, were carried out. All the antioxidant activities were compared with standard antioxidants such as BHA and α-tocopherol acetate. Th...

https://www.tandfonline.com/doi/pdf/10.1080/13880200701741088

Kamlesh Dhalwal

Papers

Simultaneous quantification of bergenin, catechin, and gallic acid from Bergenia ciliata and Bergenia ligulata by using thin-layer chromatography

Application of quality control principles to herbal drugs.

Evaluation of the Antioxidant Activity of Sida cordifolia.

Evaluation of In Vitro Antioxidant Activity of Sida rhombifolia (L.) Ssp. retusa (L.)

Antioxidant Profile and HPTLC-Densitometric Analysis of Umbelliferone and Psoralen in Aegle marmelos.