br Ethical approval br Conflict of interest br
Conflict of interest
Acknowledgements We thank the Australian Government\'s Cooperative Research Centre Program and the China Scholarship Council for financial support. We would also like to acknowledge the support of staff from the Postharvest Biosecurity and Food Safety Laboratory (Murdoch University) for providing technical assistance.
Introduction Diabetes mellitus is a metabolic disorder characterized by chronic hyperglycaemia leading to a progressive generation of oxidation products derived from glucose. Glucose is oxidized by the transition-metal-dependent reaction to form enediol radical anion that is converted into reactive ketoaldehydes and to superoxide anion radicals. These superoxide anion radicals undergo dismutation to produce hydrogen peroxide radicals and it may lead to production of extremely reactive hydroxyl radicals in the presence of transition metals [1,2]. These reactive oxygen species affects the Atglistatin of carbohydrates, proteins, fat, electrolytes and water in the human body due to increased oxidative stress. Recent evidences suggest that oxidative stress and changes in the formation of reactive species play major roles in the onset of diabetic complications . Nowadays, several drugs are commercially available and used to treat diabetic complications. However, some of the standard drugs such as sulfonylureas, biguanides and alpha glucosidase inhibitors such as acarbose, glinides and miglitol cause side effects nausea, liver disorders, flatulence, abdominal pain, renal tumours, low blood glucose, dark urine and hepatic injury [4–6]. Therefore, new antioxidant and anti-diabetic drugs from medicinal plants are needed to replace these synthetic drugs. Currently, the consumption of fruits and vegetables has been used worldwide for health benefits because of the presence of nutritive and non-nutritive chemicals from medicinal plants which protect the humans from oxidative stress related disorders. Although the wild fruits are nutritious, more consumption of such fruits is hazardous to our body, therefore before eating it must be checked whether it contains any anti-nutritional factors. The anti-nutritional factors such as trypsin inhibitors and tannins inhibit the protein digestion, growth, iron and zinc absorption . Natural antioxidants from edible plants are source for dietary components to promote healthy life. For example, α-amylase and α-glucosidase inhibitors are considered as one of the effective measures for regulating type II diabetes by preventing the glucose oxidation . Breynia retusa (commonly known as Cup Saucer plant) belongs to the family Euphorbiaceae. Macerated B. retusa leaf juice is used to cure body pain, skin inflammation, hyperglycaemia, diarrhoea and diuretic. The fruits have been used for dysentery and twigs used for toothache [9,10]. Young leaves are cooked and used as poultice to hasten suppuration [11,12]. Literatures survey showed that B. retusa leaves have good total phenolic contents, antioxidant  and anti-diabetic activity [14,15]. These studies can be taken as a strong platform to carry out antioxidant and anti-diabetic potentials in B. retusa. Hence, the present investigation on leaf and fruit was undertaken to study the nutritional composition, anti-nutritional, total phenolic content, antioxidant and anti-diabetic properties of B. retusa.
Materials and methods
Results and discussion
Conclusion The present study confirms the nutritional value of B. retusa leaves as indicated by high total phenolic content that have the ability to reduce the oxidative stress related disorders by scavenging different free radicals. Chemical composition with strong antioxidant properties of B. retusa correlated to strong inhibition of α-amylase and α-glucosidase enzymes which might regulate the hyperglycaemia and other diabetic complications. Our results suggest that dietary compounds from B. retusa can be used as a nutritional food supplement against disorders related to oxidative stress such as diabetes or others. Further studies will be conducted on identification of dietary compounds, molecular mechanisms involved in antioxidant activity and determination of their efficacy by in vivo studies.