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Int J Pharm Pharm Sci. Anti-diabetic effect of dietary mango Mangifera indica L. peel in streptozotocin-induced diabetic rats. Your purchase has been completed. Your documents are now available to view. Open Access Published by De Gruyter Open Access January 10, From the journal Open Chemistry.

Download article PDF. Cite this Share this. Abstract Among various diseases in humans, diabetes is one of the most complicated disorders resulting either from the malfunctioning of β cells, causing a poor discharge of insulin from them, or poor functioning of the liberated insulin.

Graphical abstract. Keywords: peel ; pomace ; seed ; waste ; fruits ; polyphenols ; functional components ; physiological benefits ; nutra-pharmaceutical ; diabetes.

Table 1. Polyphenols in diabetes management — in vitro studies. Table 2. Polyphenols in diabetes management — in vivo studies. GAE gallic acid equivalent. DW dry weight. PWGPE purified white grape pomace extract.

QE quercetin Equivalent. µg microgram. RE rutin equivalent. CE catechin equivalent. TE tannic acid equivalent. TAE tannic acid equivalent. CatE catechin equivalent. DM dry matter. ddp dried defatted pomace.

Funding information: No funding was received. Author contributions: All authors took an active part in the collection, processing, and description of the presented literature data Conflict of interest: The authors declare no conflict of interest.

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Cite this article. MLA APA Harvard Chicago Vancouver. Malik, Faiqa, Iqbal, Aqsa, Zia, Sabika, Ranjha, Muhammad Modassar Ali Nawaz, Khalid, Waseem, Nadeem, Muhammad, Selim, Samy, Hadidi, Milad, Moreno, Andres, Manzoor, Muhammad Faisal, Kowalczewski, Przemysław Łukasz and Aadil, Rana Muhammad.

Malik, F. Role and mechanism of fruit waste polyphenols in diabetes management. Open Chemistry , 21 1 , and Aadil, R. Open Chemistry, Vol. Malik F, Iqbal A, Zia S, Ranjha M, Khalid W, Nadeem M, Selim S, Hadidi M, Moreno A, Manzoor M, Kowalczewski P, Aadil R. Open Chemistry.

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Computational and experimental investigation of antibacterial and antifungal properties of Nicotiana tabacum extracts. Reinforcement of cementitious mortars with hemp fibers and shives. Several polyphenols are reported to increase glucose-stimulated insulin secretion GSIS , including epicatechin Hii and Howell, , quercetin Hii and Howell, ; Youl et al.

However, their reported mechanism of action varies. The effect of genistein was mediated by intracellular accumulation of cAMP due to adenylyl cyclase activity, rather than inhibition of PDE Liu et al.

Not all polyphenols stimulate insulin release. In fact, chrysin and naringenin can inhibit insulin secretion Hii and Howell, , while there is conflicting evidence as to whether resveratrol is an insulin secretagogue or inhibits secretion Chen et al.

Some polyphenols are reported to upregulate components of the insulin signaling pathway. Pancreatic expression of Ins-1, ngn-3 and PDX1, were increased by CPP extract in rats with alloxan-induced diabetes, while IRS-1 expression was increased in the liver Iftikhar et al.

Resveratrol supplementation in T2DM patients increased the ratio of phosphorylated Akt to unphosphorylated Akt in platelets Brasnyo et al. Curcumin decreased plasma levels of GSK-3β, overexpression of which is associated with insulin resistance, in subjects at risk of developing T2DM Thota et al.

Polyphenols may be able to increase glucose uptake in various tissues. Green tea supplementation increased the number of insulin binding sites Wu, Juan, Ho, et al. Quercetin increased GLUT-4 expression in the adipose tissue, skeletal muscle, and serum of mice with alloxan-induced diabetes Alam et al.

Resveratrol increased phosphorylated Akt and GLUT-4 protein expression in the skeletal muscle of STZ-treated rats Chi et al. In C 2 C 12 myotube cells, resveratrol increased glucose uptake, which was blocked by PI3K inhibition, suggesting resveratrol increases GLUT-4 expression and glucose uptake by skeletal muscle via a PI3K-Akt pathway-dependent mechanism Chi et al.

The ability of polyphenols to upregulate GLUT-4 may also be via activation of AMPK. Resveratrol Penumathsa et al. Curcumin also inhibited pyruvate dehydrogenase kinase 4 expression and phosphorylation of glycogen synthase in skeletal muscle, suggesting increased glucose oxidation and glycogen synthesis Na et al.

Evidence suggests that several polyphenols can inhibit hepatic glucose production by reducing gluconeogenic enzyme activity and upregulating glycolytic enzyme activity. EGCG inhibits hepatic glucose production Waltner-Law et al. Conversely, it upregulated expression of the glycolytic enzyme phosphofructokinase and GLUT-1 Wolfram et al.

Similarly, resveratrol decreased hepatic G6Pase and PEPCK activity, and increased glucokinase activity and pyruvate kinase expression Do et al. Quercetin reduced G6Pase and FBPase activity in liver, kidney, and skeletal muscle Alam et al. Quercetin also increased hepatic hexokinase activity in alloxan-induced diabetic mice Alam et al.

Likewise, CPP extract decreased G6Pase and FBPase activity, and restored the activities of G6P dehydrogenase and hexokinase in alloxan-treated rats Iftikhar et al. In STZ-rats, kaempferol demonstrated the ability to reduce hepatic glucose production and pyruvate carboxylase activity, and increase glucokinase activity and glycogen storage Alkhalidy et al.

Taken together, available evidence suggests that some polyphenols may augment GSIS, upregulate the insulin signaling pathway, increase glucose uptake and utilization, and reduce endogenous glucose production, which may partly explain their reported blood glucose-lowering and glucose tolerance-enhancing effects.

Some of these effects may also be explained by improved β-cell survival and function rather than a direct metabolic effect. High circulating levels of FFA are known to increase insulin resistance. FFA are metabolized through β-oxidation to produce acetyl-CoA and ATP, or to make other metabolites such as diacylglycerides and ceramides, which are suggested to decrease insulin sensitivity Corcoran et al.

This lipid-lowering effect of polyphenols may be due to alteration of the expression and activity of enzymes involved in lipid uptake and metabolism.

Curcuminoid treatment in patients with T2DM increased serum lipoprotein lipase LPL activity Na et al. Since LPL converts triglycerides into FFA, it was suggested that curcuminoids increase uptake and utilization of FFA in tissues.

In L6 myotubes, curcumin increased CD36 and CPT-1 expression, and phosphorylation of acetyl-CoA carboxylase, suggesting that curcumin lowers FFA levels by increasing uptake and β-oxidation in skeletal muscle Na et al.

This effect was mediated by activation of AMPK. The pleiotropic effects of many polyphenols may be useful in combatting T2DM, especially considering its equivocal etiology, multiple dysfunctional cellular pathways, and uncertainty over which are causes and which are consequences of the disease.

Polyphenol treatment could have pancreatic and extra-pancreatic effects. Inhibition of amyloid formation, antioxidant, anti-inflammatory, mitochondrial and ER-stress protective effects could preserve β-cells, while anti-inflammatory, serum lipid lowering, and insulin-like effects particularly on liver enzyme activity could improve whole-body insulin sensitivity and help ameliorate hyperglycemia.

The bioavailability and metabolism of polyphenols should be considered in future studies. Many available studies have shown an effect after oral administration in animal models, but clinical studies have provided variable results, which could be due to dose, methodology or differences in bioavailability or metabolism.

Some polyphenols are bioavailable in their native form. ECGC is found in plasma in free form following oral administration, albeit at low concentrations Andreu-Fernandez et al.

Resveratrol can be absorbed in its native state but can also undergo considerable microbial metabolism before absorption Bode et al. However, some polyphenols are largely metabolized before absorption. Rutin is metabolized by microbiota before the metabolites are absorbed in both humans and rodents Baba et al.

There is significant interspecies variation in the metabolism of xenobiotics. For example, resveratrol and dihydroresveratrol in human subjects after oral administration have been observed at higher plasma levels than those obtained in mice given considerably higher doses Timmers et al.

Furthermore, interindividual differences in the metabolism and absorption of compounds may underlie clinical variability. The level of bioavailability of resveratrol between individuals is inconsistent. Microbial metabolism between individuals can vary greatly, which may explain the conflicting results from human trials Bode et al.

The bioactivity of most metabolites of polyphenolic compounds is poorly understood. The plasma level of free, unconjugated quercetin following rutin supplementation is reported to be low Erlund et al. Despite this, an antidiabetic effect has been reported following oral rutin administration in vivo , raising the question of whether one or more metabolites are responsible Aitken et al.

So far, there has been little published research on the activities of metabolites and their link to the clinical efficacy of the parent compound. Bioavailability and metabolism should be considered in the design of future intervention studies Manach et al.

An avenue for further research may be to design drugs based on polyphenolic structures that may be more stable or targeted in the body, or with novel delivery systems, to improve absorption and efficacy.

The inhibitory effects of polyphenols on hA aggregation are often studied in vitro in aqueous solutions; however, this does not accurately recapitulate the lipid membrane environment in which hA aggregates physiologically. Studies utilizing a variety of membrane-mimetic model systems have demonstrated that lipid membranes containing an anionic charge accelerate fibril formation Knight et al.

However, few studies have reported on the ability of polyphenols to inhibit hA aggregation in such an environment, with results only for EGCG and resveratrol reported to our knowledge.

By contrast, resveratrol inhibited hA aggregation even in the presence of lipids Evers et al. Further investigation into whether other polyphenols retain their inhibitory effect on amyloid formation in a lipid membrane environment would be valuable.

This opens the possibility that polyphenols, especially with their pleiotropic effects, may be an effective treatment for several diseases. The antioxidant and anti-inflammatory activities of polyphenols have non-disease specific, beneficial effects that may be especially useful for those diseases with a complicated and varied etiology like T2DM.

Additionally, with their well-tolerated safety profile there is the possibility for use of polyphenolic compounds as a preventative as well as therapeutic treatment.

Future studies should carefully consider the methodologies they use. As discussed, ThT fluorescence should not be used as the sole method to measure inhibition of hA aggregation by compounds due to the possibility of competitive binding Daval et al.

Circular dichroism, atomic force microscopy or other methods should be utilized to verify results. High resolution nuclear magnetic resonance or mass spectrometry techniques could be used to probe the specific interaction of compounds with hA, which could provide vital insights into the binding mechanism and facilitate rational drug design based on polyphenolic compounds.

For in vivo studies, the appropriateness of the animal model used must also be considered, as many models recapitulate part of but not the entirety of T2DM. Many commonly used models, such as STZ or alloxan-induced diabetic animals, are more reminiscent of T1DM than T2DM.

Few studies utilize transgenic mice that express the human variant of amylin which forms amyloid Aitken et al. Similarly, the use of cell lines that overexpress hA in in vitro studies, rather than applying exogenous hA to cells, may be more physiologically relevant.

For decades, T2DM was considered as predominantly a disease caused by insulin resistance and therapies focused on lowering blood glucose levels. However, in recent years there has been a paradigm shift, from a glucose-centric to a β-cell-centric view of T2DM Saisho, This evolution recognizes that T2DM occurs only when β-cell function has failed.

The etiology underlying this process is unclear; however, evidence suggests that cytotoxic hA oligomers, oxidative stress, inflammation, ER stress and mitochondrial dysfunction all play their part, even if a single causative mechanism if there is indeed one is yet to be determined.

Therefore, agents that target multiple pathways may lead to better therapeutic outcomes. In this regard, polyphenols are promising candidates with their ability to inhibit amyloid formation Porat et al.

As hA oligomers have been shown to contribute to oxidative stress Zraika et al. Additionally, polyphenols have more direct effects on reducing oxidative stress and inflammation, as well as modulating other cellular pathways with beneficial metabolic effects.

Thus, polyphenols may have beneficial effects on both β-cell survival and whole-body insulin sensitivity. Both scientists and the public have shown strong interest in polyphenols, their potential health benefits, and their use as treatments for a multitude of diseases, especially surrounding EGCG, resveratrol, and curcumin.

However, hopes for a new effective therapeutic treatment based on the findings summarized here have yet to come to fruition. Clinical trials have shown some encouraging but controversial results. The greatest challenge appears to be achieving a consistent therapeutic effect.

The current impasse may be due to incomplete understanding of the molecular basis of polyphenol action, alongside the complexity of multifactorial diseases such as T2DM. Further research could usefully focus on the following: 1 the bioavailability of compounds in humans and establishing a therapeutic dose range; 2 the identity and activity of metabolites; 3 consideration of methodology for in vitro studies and in vivo trials and ensuring that clinical trials examine appropriate parameters; 4 design of compounds or delivery systems with greater stability and improved and reproducible efficacy.

Natural polyphenols remain an active area of research for many diseases Khursheed et al. Improved compounds and robust study designs will enable greater understanding of how to utilize these interesting, multifunctional compounds. TN wrote the article, GC revised the article and contributed discussions on the content.

Our research programme has been funded by the Ministry for Business, Innovation and Employment, New Zealand Government. Funding identification: CONTENDRP-UOA UOAX for research programme entitled Optimized disease-modifying therapy for type-2 diabetes.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers.

Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher. We thank Cynthia Tse for her help in reviewing the manuscript and providing administrative assistance. Abedini, A. Time-resolved Studies Define the Nature of Toxic IAPP Intermediates, Providing Insight for Anti-amyloidosis Therapeutics.

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Quercetin, a Flavonoid Antioxidant, Prevents and Protects Streptozotocin-Induced Oxidative Stress and Beta-Cell Damage in Rat Pancreas. Daval, M.

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Rutin Prevents LTA Induced Oxidative Changes in H9c2 Cells. Food Sci. Hadi, S. Improvement in Fasting Blood Sugar, Anthropometric Measurement and Hs-CRP after Consumption of EpigallocatechinGallate EGCG in Patients with Type 2 Diabetes Mellitus.

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Iftikhar, A. Effect of Caesalpinia Bonduc Polyphenol Extract on Alloxan-Induced Diabetic Rats in Attenuating Hyperglycemia by Upregulating Insulin Secretion and Inhibiting JNK Signaling Pathway.

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Phytother Res. One problem is that you rely on people to give you accurate information about their diets. Another challenge is that polyphenol levels can vary considerably. For instance, organic fruits sometimes have higher levels of polyphenols than nonorganic fruits.

Other factors, like rainfall, sun exposure , and how food is stored and prepared can also alter a food's polyphenol levels. Above, we outlined epidemiological studies that included large numbers of people. These are important in helping scientists spot patterns and associations.

Then, scientists run smaller, more tightly controlled studies to understand whether those associations are causal. These are clinical trials. The researchers recruited 86 participants with overweight or obesity and assigned them to four groups.

Each followed a different diet, some of which were rich in polyphenols. At the beginning and end of the study, the scientists gave the participants a test meal and measured their blood sugar responses.

At the end of the study, participants with the high-polyphenol diets had significantly reduced blood sugar responses. The scientists recruited 34 people with prediabetes. People with prediabetes have higher than usual blood sugar levels, but these are still too low for a diagnosis of type 2 diabetes.

Half the participants took an acacia polyphenol supplement each day for 8 weeks, and the other half took a placebo. The team found that participants taking the polyphenol supplement had significantly reduced blood sugar responses to a meal at the end of the study, compared with the beginning.

This wasn't true for the people who took the placebo. By now, several clinical trials have measured the positive effects of polyphenols on blood sugar control. So, the next question is …. If these wonderful plant compounds really do influence blood sugar control and protect against type 2 diabetes, how are they doing it?

Evidence suggests that polyphenols probably work their magic via a number of routes. Enzymes need to snip them into simple sugars, like glucose, before they can enter your blood.

Polyphenols slow this process by inhibiting some of the carb-snipping enzymes. Once carbs have been chopped up into glucose, they move through your gut lining using glucose transporters. Polyphenols may also interact with these transporters, slowing the movement of glucose from your gut to your blood.

So, polyphenols seem to hinder the breakdown of larger carb molecules and slow their passage into your blood. Evidence from lab and animal studies suggests that polyphenols can help your body remove glucose from your blood more quickly. It might do this by increasing your insulin sensitivity, which means that glucose is more efficiently shunted out of your blood.

Also, lab studies suggest that polyphenols can increase the number or sensitivity of glucose transporters on muscles. This means that glucose is moved from your blood into your muscles more efficiently. Instead, they reach your large intestine, where they feed your gut bacteria and keep them happy.

Some evidence suggests that polyphenols might increase numbers of Bifidobacteria in your gut. And increased numbers of Bifidobacteria seem to be associated with better blood sugar control.

The full story of how gut bacteria are involved is yet to be told. Scientists are still digging into the links between polyphenols, blood sugar control, and type 2 diabetes. But evidence is mounting that these plant compounds can positively influence your blood sugar control and may reduce your type 2 diabetes risk.

As researchers continue to uncover the link between these plant chemicals and the risk of developing type 2 diabetes, upping your polyphenol intake is a safe bet. Aside from blood sugar control, polyphenols may also protect heart, gut, and skin health.

Scientists are still unraveling the roles that polyphenols play in our health. But because plant foods that are good for your health contain high levels of polyphenols , increasing your intake of these plants will likely benefit you.

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The minimum value reported was Chai et al. Coumarins belong to the benzopyrone family commonly found in many medicinal plants [ 93 ]. Coumarins are fused benzene and α-pyron ring that represents a significant low-molecular phenol group [ 94 ]. Coumarins are secondary metabolites, found in a wide variety of higher plants, but also detected in some microorganisms and animal species [ 95 ].

Natural coumarins are divided into different classes on the basis of their chemical enormous diversity, such as simple coumarins, isocoumarins, furanocoumarins, and pyranocoumarins [ 96 ]. The coumarins are of great interest due to their pharmacological properties.

In particular, their physiological, bacteriostatic, and anti-tumor activities make these compounds attractive backbone derivatization and screening as novel therapeutic agents [ 97 ]. A total of coumarin-derived compounds have been naturally distinguished from approximately genera in families [ 98 ].

High contents of coumarins have been found in the peel of different fruits like pomegranate, banana, orange, mango, pear, and many others. Dugrand et al. Mercolini et al. Masuda et al. In extracts from various varieties of citrus peel coumarins, the concentration was 1.

Pear peel observed coumarin concentration The banana peel acetone extract contained 0. The peel of mango has The coumarin content in pomegranate peel was 0. In other study, the highest coumarin content in pomegranate peel was Correspondingly, the peel pomegranate by ethanol extracts found 5.

Coumarin contents have found in various fruit pomace like olive, grape, citrus, guava, and many others. The identification of coumarins contents in pomace olive by the methanolic extraction method was 0. The varieties of grape pomace contained 0.

Multari et al. Ribeiro da Silva et al. Correspondingly, Mota et al. Excess amount of coumarins has found in many fruit seed like citrus, pomegranate, and many more.

Russo et al. The maximum concentration of coumarins in pomegranate seed was 1. Yang et al. Stilbenes are a small family of plant secondary metabolites derived from the phenylpropanoid pathway and produced in a number of unrelated plant species [ ]. Although their molecular backbone consists only of 1,2-diphenylethylene units, stilbenes show an enormous diversity with regard to the different units present, the degree of polymerization, and the pattern of oligomer construction.

In plants that naturally produce stilbenes, these metabolites are generally accumulated in both free and glycosylated forms. Glycosylation of stilbenes could be involved in their storage, transport from cytoplasm to apoplasm, and protection from peroxidative degradation [ ].

Stilbenes are a small family of plant secondary metabolites derived from the phenylpropane pathway and produced in many unrelated plant species [ ]. Although their molecular backbones consist of only 1,2-diphenylethylene units, stilbenes show huge differences in the different units present, degree of polymerization, and oligomeric structural patterns.

In plants that naturally produce stilbene, these metabolites typically accumulate in free and glycosylated forms. Glycosylation of stilbenes may be involved in their storage, transport from the cytoplasm to the apoplast, and protection from peroxidative degradation [ ].

Genetic modification of tomato plants results in the accumulation of different levels of four stilbene species i. Stilbenes preferentially accumulate in the peel in glycosylated form, both in immature and mature stages. The highest amounts of trans -resveratrol and trans -resveratrol were found in the peels of fruits harvested at maturity [ ].

By-products from the food industry, such as passion fruit seeds, have increased significantly due to their added value due to their properties such as potential antioxidant activity. The purpose of this study was to determine the presence of paclitaxel and resveratrol in various extracts of passion fruit Passiflora edulis seeds from Madeira, using commercial passion fruit oil as a reference.

Commercial oils and extracts obtained by the traditional Soxhlet method with ethanol and acetone do not show the presence of two stilbenes, paclitaxel and resveratrol [ ]. Type 2 diabetes mellitus is described as a condition in which the insulin produced by the pancreatic β cells faces resistances from the insulin receptors that are embedded in the bodily cells due to the deposition of fatty deposits in respective receptors.

As a result of this, at initial stages, the levels of insulin are high in the blood, but later the levels drop as the β cells become defective [ ]. Various studies have emphasized that intake of polyphenols in the diet especially phenolic, flavonoids, tannins, and coumarins has an association with the reduction in the prevalence of type 2 diabetes mellitus [ , ].

The hypoglycemic effects of polyphenols are primarily attributable to reduced intestinal absorption of dietary carbohydrates and regulation of the enzymes involved in glucose metabolism, enhancing glucose metabolism, β-cell function, and insulin action, insulin stimulation, and insulin secretion antioxidant and anti-inflammatory effects of components.

The suppression of α-glucosidase and α-amylase, the major enzymes responsible for the digestion of dietary carbohydrates to glucose, is one of the most well-known effects of polyphenols on carbohydrate metabolism. Several studies have demonstrated that polyphenolic substances can also modulate postprandial glycemia and prevent the onset of glucose intolerance via a facilitated insulin response and decreased production of glucose-dependent insulinotropic polypeptide and glucagon-like polypeptide-1 [ 31 , ].

Natural fruits with high polyphenol content, such as blackberries, red grapes, and apricots, can regulate carbohydrate metabolism through a variety of methods, including maintaining and repairing beta-cell function and improving insulin releasing activity and cellular glucose absorption [ ].

A previous study shows that polyphenols found in food items like coffee, cocoa, propolis, guava tea, grape seeds, whortleberry, and red wine have been found to have anti-diabetic characteristics by increasing glucose metabolism and reducing insulin resistance, vascular function, and HbA1c levels in T2D patients [ 29 ].

Polyphenols reduce hyperglycemia and increase insulin sensitivity and acute insulin secretion. Some of the mechanisms that could be involved: insulin secretion stimulation, inhibition of carbohydrate digestion, glucose uptake in insulin-sensitive tissues, modulation of glucose release from the liver, modulation of intracellular signaling pathways, activation of insulin receptors, and gene expression [ 28 ].

Protection of pancreatic cells from glucose toxicity, antioxidant properties, anti-inflammatory properties, inhibition of amylases or glucosidases, decreased starch digestion, and prevention of advanced glycation end products generation is all advantages of dietary polyphenols for T2D [ ].

Glycation of proteins is thought to have a major role in diabetes complications and illnesses. Cao et al. The ligand-binding properties change when HSA is glycated. Gao et al. They do so by either inhibiting the absorption of glucose in the GI tract or activating the insulin receptors in the cells.

Chukwum and colleagues [ ] reported that polyphenols reduce the carbohydrate digestion and increase the uptake of glucose being stored in the liver. Similarly, Ramya et al. Niederberger and coworkers [ ] reported that the polyphenol phloridzin has the ability to inhibit the activity of SGLT 1 a glucose transporter present in the small intestine, thus minimizing the uptake of glucose from the intestine into the blood.

Moloto et al. The OH group of these polyphenols forms connection with the active sites of enzyme and thus hinders their capacity to hydrolyze the carbohydrates. Tables 1 and 2 show various in vitro and in vivo studies. The present review summarizes that waste generated during the processing of fruits contains ample quantities of polyphenols in it.

The major polyphenols that are present in the wasted portion of fruits seeds, peel, and pomace mainly include the phenolic acids, flavonoids, and tannins.

Polyphenols are an important class of phytochemicals and offer various benefits to humans upon consumption. One of the major benefits of these polyphenols may be their capability to cure various degenerative diseases, and diabetes is one among them. From clear investigation, it was found that polyphenols show a positive effect in the management of diabetes, particularly the type 2.

It is suggested that instead of discarding the inedible components of fruits proper extraction procedures must be utilized for the recovery of these polyphenols from the fruit wastes so that beneficial products can be made out of them and treatment of various ailments including diabetes can be facilitated by using these bioactive commodities.

Besides this such practices would also minimize the harmful impact of wastes on the environment. It is therefore advisable to utilize waste-derived polyphenols from the fruits for the recovery of these functionally essential constituents so that they can be used in various formulations for the treatment and cure of diabetes and other disorders as they are considered to be far better than the synthetic products because they provide more benefits and fewer harms.

CVDs cardiovascular diseases. Author contributions: All authors took an active part in the collection, processing, and description of the presented literature data. Conflict of interest: The authors declare no conflict of interest. Ethics approval: The conducted research is not related to either human or animal use.

Data availability statement: Data sharing is not applicable to this article as no datasets were generated or analyzed during the current study.

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