Draba cemileae (Karaer): Phytochemical composition, antioxidant and enzyme inhibitory activity
Introduction
Plant polyphenols are compounds containing hydroxyl groups attached to aromatic rings in their structure (Zhou et al., 2019). It is estimated that the number of plant polyphenols identified so far, including those that can be consumed, is several thousand (Stagos, 2020). Plants have been the richest source of exogenous antioxidant compounds for many years. Authorities claim that almost two-thirds of the plant species distributed on the world have various biological/pharmacological activities and almost all of them contain strong antioxidant compounds (Krishnaiah et al., 2011). After the discovery of ascorbic acid, the first exogenous antioxidant compound, plants were relied upon for the treatment of many diseases caused by increased oxidative stress (Boo, 2019; Burgos-Morón et al., 2019; Pawlowska et al., 2019). Many researchers agree that polyphenols can be used as antioxidants in the treatment of diseases caused by oxidative stress (Jin et al., 2018). Therefore, plant-derived antioxidants are a promising source of reference to combat the problems caused by oxidative stress (Jin et al., 2018; Kasote et al., 2015).
Diabetes is a chronic disease that occurs due to inadequate carbohydrate metabolism or impairment of cell surface receptors. The high level of glucose in the blood causes many health problems (Mathers and Loncar, 2006; Shaw et al., 2010). The enzymes responsible for metabolizing polysaccharides or disaccharides in the body are α-amylase and α-glucosidase. Inhibiting these enzymes to slow down carbohydrate metabolism is one of the important strategies in the treatment of diabetes (Azad et al., 2017; Kim et al., 2000; Ramasubbu et al., 1996; Zhen et al., 2017). Today, some synthetic enzyme inhibitors are used to reduce the blood glucose level. However, these substances cause some side effects such as edema, hypoglycemia, excessive weight gain, anemia, gastrointestinal disorders and lactic acidosis (Magaji et al., 2020). Therefore, researchers also focused on plants to discover new and alternative α-amylase and α-glucosidase inhibitors to treat diabetes.
In addition to the therapeutic properties mentioned above, phytochemicals also exhibit promising activities for the treatment of disorders in the cholinergic system. It has been determined that the metabolic activity of cholinesterases (ChEs) is closely related to the pathology of various neurological diseases, especially Alzheimer's disease (AD). Especially in AD, high ChE activity contributes to the increase of amyloid plaque aggregation as well as slowing down neural conduction. Symptoms such as memory loss, irreversible neurological tissue degeneration, inability to perform daily vital activities are frequently seen in AD (Choubdar et al., 2019; Vickers, 2017). Today, the most effective approach in the treatment of AD is the use of cholinesterase inhibitors (donepezil, galantamine, rivastigmine) (Ahmad et al., 2019; Yiannopoulou and Papageorgiou, 2020). Despite being clinically effective, these compounds have been reported to have common side effects such as diarrhea, nausea, and vomiting. Therefore, researchers have focused on the development or isolation of new phytochemicals (Cheenpracha et al., 2016; García et al., 2015; Kiełczewska et al., 2021; Liu et al., 2017; Mohebbi et al., 2018; Richmond et al., 2013).
Tyrosinase is a critical enzyme that converts monophenols to diphenols and then to melanin through o-quinone oxidation (Tian et al., 2019; Yu et al., 2019). Melanin is a pigment found in the skin of organisms that acts as a filter against UV rays. However, if it is synthesized excessively, freckles and age spots occur on the skin. Overexpression of melanin synthesis has also been reported to be associated with melanoma (Chang, 2009). Polyphenol oxidases, which are structurally similar to tyrosinase, cause browning in fruits and vegetables. Browning leads to deterioration of quality and taste in these foods (Brotzman et al., 2019; Chang, 2009). Inhibition of tyrosinase is one of the most rational solutions in the treatment of skin diseases due to abnormal melanin synthesis in medicine, in the preparation of skin whitening preparations in the cosmetics industry and in the prevention of browning in the food industry. Today, there are some synthetic substances used as tyrosinase inhibitors. However, natural tyrosinase inhibitors are more preferred on the grounds that their biocompatibility capacity is higher and they are sustainable. For this reason, researchers are investigating plant species for the discovery of new and effective tyrosinase inhibitors (Wang et al., 2020; Zolghadri et al., 2019).
In this study, roots, leaves and seeds of Draba cemileae (Karaer) were evaluated for their chemical compositions and biological activities. In addition to spectrophotometric and chromatographic analysis, total antioxidant activities of the extracts based on their chlorogenic acid equivalents (CAEs) of total phenolic and flavonoid contents were determined by performing square wave stripping voltammetry (SWSV) on multi-walled carbon nanotube paste electrode (MWCNTPE).
Section snippets
2.1. Plant material and extract preparation
D. cemileae was collected from Tamzara village, Sebinkarahisar, Giresun-Turkey on 14 June 2020 (1348 m, 40° 20’ 47.67”N 38° 26’ 32.62”E), authenticated by Dr. Mustafa Cuce, and deposited (Herbarium number: KTUB, CUCE & GULTEPE 796) at the Department of Biology, Karadeniz Technical University (Trabzon-Turkey). The plant was firstly divided into different parts (roots, leaves, and seeds), air-dried in the shade for several weeks, and then ground using a laboratory mill.
Air-dried samples (2 g)
3.1. Chemical composition
The yields of the MeOH extracts obtained from the roots, leaves and seeds of D. cemileae were given in Table 1. According to the data in the table, the highest yield belonged to root extract (11.9%). It was followed by the seed and leaf extracts, respectively.
Data obtained from the spectrophotometric analysis were also presented in Table 1. While leaves were the richest plant parts in terms of phenolics (22.84 mg GAEs/g), the seed extract was found to contain higher amount of flavonoids than
Conclusions
The lack of a similar study on D. cemileae makes the present study important in terms of the literature. It was concluded that the extracts obtained from leaves and seeds exhibited higher antioxidant and enzyme inhibitory activity than the root extract. Although not all of the phytochemicals in the extracts have been documented, p-hydroxybenzoic acid, chlorogenic acid and especially rosmarinic acid in the seed extract are thought to contribute significantly to the activities. It was concluded
Declaration of Competing Interest
The authors confirm that there are no known conflicts of interest.
References (60)
- et al.
Cardio-protective and antioxidant properties of caffeic acid and chlorogenic acid: mechanistic role of angiotensin converting enzyme, cholinesterase and arginase activities in cyclosporine induced hypertensive rats
Biomed. Pharmacother.
(2019) - et al.
Synthesis, in-vitro cholinesterase inhibition, in-vivo anticonvulsant activity and in-silico exploration of N-(4-methylpyridin-2-yl) thiophene-2-carboxamide analogs
Bioorg. Chem.
(2019) - et al.
Synthesis and tyrosinase inhibitory activities of 4-oxobutanoate derivatives of carvacrol and thymol
Bioorg. Med. Chem. Lett.
(2019) - et al.
Acetylcholinesterase inhibitory activity and molecular docking study of steroidal alkaloids from Holarrhena pubescens barks
Steroids
(2016) - et al.
Inhibitory effects on mushroom tyrosinase by p-alkoxybenzoic acids
Food Chem.
(2005) - et al.
New classes of carbazoles as potential multi-functional anti-Alzheimer's agents
Bioorg. Chem.
(2019) - et al.
Solanocapsine derivatives as potential inhibitors of acetylcholinesterase: synthesis, molecular docking and biological studies
Steroids
(2015) - et al.
Comparison of antioxidant activities of selected phenolic compounds in O/W emulsions and bulk oil
Food Chem.
(2021) - et al.
The synthesis and cholinesterase inhibitory activities of solasodine analogues with seven-membered F ring
J. Steroid Biochem. Mol. Biol.
(2021) - et al.
Salvia cadmica: phenolic composition and biological activity
Ind. Crops Prod.
(2016)
A review of the antioxidant potential of medicinal plant species
Food Bioprod. Process.
Isosteroidal alkaloids as potent dual-binding site inhibitors of both acetylcholinesterase and butyrylcholinesterase from the bulbs of Fritillaria walujewii
Eur. J. Med. Chem.
Alpha amylase, alpha glucosidase and glycation inhibitory activity of Moringa oleifera extracts
S. Afr. J. Bot.
Acetylcholinesterase inhibitory activity of a neurosteroidal alkaloid from the upside-down jellyfish Cassiopea andromeda venom
Rev. Bras. Farmacogn.
Ajuga chamaecistus subsp. scoparia (Boiss.) Rech. f.: a new source of phytochemicals for antidiabetic, skin-care, and neuroprotective uses
Ind. Crops Prod.
Onosma heterophyllum: phenolic composition, enzyme inhibitory and antioxidant activities
Ind. Crops Prod.
Synthesis and acetylcholinesterase inhibitory activity of polyhydroxylated sulfated steroids: Structure/activity studies
Steroids
Phenolic profile, safety assessment, and anti-inflammatory activity of Salvia verbenaca L
J. Ethnopharmacol.
Selective in vitro and in silico butyrylcholinesterase inhibitory activity of diterpenes and rosmarinic acid isolated from Perovskia atriplicifolia Benth. and Salvia glutinosa L
Phytochemistry
Global estimates of the prevalence of diabetes for 2010 and 2030
Diabetes Res. Clin. Pract.
Phytochemical profile and antioxidant activity of Dracocephalum moldavica L. seed extracts using different extraction methods
Food Chem.
Flavanoids derivatives from the root bark of Broussonetia papyrifera as a tyrosinase inhibitor
Ind. Crops Prod.
Animal communication: when i'm calling you, will you answer too?
Curr. Biol.
Rosmarinic acid protects rats against post-stroke depression after transient focal cerebral ischemic injury through enhancing antioxidant response
Brain Res.
Tyrosinase inhibitory performance of hydrolysate from post-washing liquor of steam exploded corn stalk and its fractionation enhancement
Ind. Crops Prod.
Five individual polyphenols as tyrosinase inhibitors: inhibitory activity, synergistic effect, action mechanism, and molecular docking
Food Chem.
Crepis foetida L. subsp rhoeadifolia (Bleb.) Celak. as a source of multifunctional agents: cytotoxic and phytochemical evaluation
J. Funct. Foods
Synthesis of novel flavonoid alkaloids as α-glucosidase inhibitors
Biorg. Med. Chem.
The cupric ion reducing antioxidant capacity and polyphenolic content of some herbal teas
Int. J. Food Sci. Nutr.
Anti-hyperglycaemic activity of Moringa oleifera is partly mediated by carbohydrase inhibition and glucose-fibre binding
Biosci. Rep.
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