The influence of heat treatment of chickpea seeds on antioxidant and fibroblast growth‐stimulating activity of peptide fractions obtained from proteins digested under simulated gastrointestinal conditions

This study presents the effect of heat treatment of chickpea seeds on biological activity of peptides obtained by in vitro gastrointestinal digestion. The most significant antiradical activity against ABTS^+? expressed as IC₅₀ value was observed for 3.5‐ to 7‐kDa peptide fraction from TC hydrolysate (41.01 μg mL^?1). In turn, peptide fraction of 3.5–7.0 kDa obtained from raw chickpea seeds hydrolysate showed the highest antiradical activity against DPPH^? and Fe²⁺ chelating activity with IC₅₀ value of 20.94 and 52.53 μg mL^?1, respectively. The highest Cu²⁺ chelating activity was observed for peptides obtained from TC hydrolysate (IC₅₀ = 56.60 μg mL^?1). Peptide fraction <3.5 kDa from TC hydrolysate demonstrated the most significant reducing power (0.362 A₇₀₀/μg mL^?1). The peptide fraction of 3.5–7 kDa from TC hydrolysate also showed the highest fibroblast growth‐stimulating activity. These results indicated that the heat treatment process has no significant effect on antiradical activity against DPPH^? and Fe²⁺ chelating ability of peptides.     

Sweet potato protein hydrolysates: antioxidant activity and protective effects on oxidative DNA damage

In this study, sweet potato protein (SPP) hydrolysates were prepared by six enzymes (alcalase, proleather FG‐F, AS1.398, neutrase, papain and pepsin). The antioxidant activities and protective effect against oxidative DNA damage of SPP hydrolysates were investigated. Alcalase hydrolysates exhibited the highest hydroxyl radical‐scavenging activity (IC₅₀ 1.74 mg mL^?1) and Fe²⁺‐chelating ability (IC₅₀ 1.54 mg mL^?1) (P < 0.05). Compared with other five hydrolysates, the hydrolysates obtained by alcalase had the most abundant <3‐kDa fractions. In addition, below 3‐kDa fractions of alcalase hydrolysates showed the highest antioxidant activities and protective effects against DNA damage through both scavenging hydroxyl radicals and chelating Fe²⁺, which was probably because of the increase in several antioxidant amino acids, such as His, Met, Cys, Tyr and Phe, as well as the hydrophobic amino acids. The results suggested that enzymatic hydrolysis could be used as an effective technique to produce high value‐added peptides products from SPP.     

Antioxidant activity of predigested protein obtained from a range of farmed edible insects

This study investigated the antioxidant activities of peptides obtained by in vitro gastrointestinal digestion of edible insects. The antioxidant potential of edible insects' hydrolysates was determined as the free radical‐scavenging activity, ion chelating activity and reducing power. The highest antiradical activity against DPPH^˙, whose IC₅₀ value is the lowest, was noted for Amphiacusta annulipes (19.1 μg/mL) and that against ABTS^˙+ was the highest for Zophobas morio (4.6 μg/mL). The peptides obtained from A. annulipes also showed the highest Fe²⁺ chelation ability (58.82%) and reducing power (0.652). The highest ability to chelate Cu²⁺ was noted for Locusta migratoria (86.05%). The locust was characterised by the highest concentration of peptides before digestion and after digestion (3.13 and 5.88 mg/mL, respectively), and the DH was 36.29%.     

Antioxidative Activity and Safety of 50% Ethanolic Red Bean Extract (Phaseolus radiatus L. var. Aurea)

ABSTRACT: This study evaluated the antioxidative activities of 50% ethanolic extract from red bean (Phaseolus radiatus L. var. Aurea). The antioxidative activities, including α,α‐diphenyl‐β‐picryl‐hydrazyl (DPPH) radicals scavenging effects, Fe²⁺‐chelating ability, and reducing power, were studied in vitro. The antioxidative activity was found to increase with the concentration of the extract to a certain extent and then level off as the concentration further increased. Compared with commercial antioxidants, the red bean extract showed less scavenging effect on the DPPH radical and less reducing power than α‐Tocopherol and BHT, but better Fe²⁺‐chelating ability. No mutagenic effect toward any tester strains was found in the 50% ethanolic extract of red bean.     

Characterisation of the phenolic and flavonoid fractions and antioxidant power of Italian honeys of different botanical origin

BACKGROUND: Twenty‐seven Italian honey samples of different floral origin were analysed for total phenolic and flavonoid contents by a spectrophotometric method and for antioxidant power and radical‐scavenging activity by the ferric‐reducing/antioxidant power (FRAP) and 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) assays respectively. In addition, the phenolic and flavonoid profiles were analysed using high‐performance liquid chromatography with UV detection (HPLC‐UV). RESULTS: The results of this study showed that honey contains copious amounts of phenolics and flavonoids. HPLC‐UV analysis showed a similar qualitative polyphenolic profile for all honey samples analysed. The main difference among samples was in the contribution of individual analytes, which was affected by floral origin. Total phenolic and flavonoid contents varied from 60.50 to 276.04 mg gallic acid equivalent kg^?1 and from 41.88 to 211.68 mg quercetin equivalent kg^?1 respectively. The antioxidant capacity was high and differed widely among samples. The FRAP value varied from 1.265 to 4.396 mmol Fe²⁺ kg^?1, while the radical‐scavenging activity expressed as DPPH‐IC₅₀ varied from 7.08 to 64.09 mg mL^?1. Correlations between the parameters analysed were found to be statistically significant (P < 0.05). CONCLUSION: The present study shows that honey contains high levels of phenolics and flavonoids and that the distribution of these compounds is influenced by the honey's floral origin. Copyright © 2009 Society of Chemical Industry     

Low‐ and Medium‐DE Maltodextrins From Waxy Wheat Starch: Preparation and Properties

The goal of the research was to prepare maltodextrins (MD) from waxy wheat starch and waxy corn starch (control). Waxy wheat starches with 0.2% protein, 0.2% lipid and ∼1% amylose were isolated from two flours by mixing a dough, dispersing the dough in excess water, and separating the starch and gluten from the resultant dispersion. The mean recoveries were 72% for the starches and 76% for the gluten fraction with 80% protein. Maltodextrins having low‐dextrose equivalence (DE) 1—2 and mid‐DE 9—10 were prepared by treatment of 15% slurries of waxy wheat starch and waxy corn starch at 95 °C for 5—10 min and 20—50 min, respectively, with a heat‐stable α‐amylase. Denaturing the enzyme and spray‐drying produced MD's with bulk densities of 0.3 g/cm ³. The powdery MD's were subjected to an accelerated‐rancidity development test at 60 °C, and an off‐odor was detected after 2 days storage for the low‐DE MD's from the two waxy wheat starches (WxWS₁‐MD 1.2 and WxWS₂‐MD 1.5), but not for the low‐DE waxy corn maltodextrin (WxCS‐MD 2.2) or a commercial waxy corn MD with DE 1. None of the mid‐DE 9—10 MD's developed off‐odor after 30 days storage at 60 °C. The experimental products WxWS₁‐MD 9.2, WxWS₂‐MD 9.9 and WxCS‐MD 9.1 showed high water‐solubility and gave 1—10% aqueous solutions of high clarity with no clouding upon cooling.     

Optimisation of antioxidant hydrolysate production from sweet potato protein and effect of in vitro gastrointestinal digestion

In this study, response surface methodology (RSM) was applied to optimise antioxidant hydrolysate production from sweet potato protein (SPP). The effects of enzyme‐to‐substrate ratio, pH value and reaction temperature on ·OH radical scavenging activity and Fe²⁺‐chelating activity of antioxidant hydrolysates from SPP were investigated. The maximum ·OH radical scavenging activity (40.10%) and Fe²⁺‐chelating activity (74.37%) of SPP hydrolysates (SPPH) were obtained at an enzyme‐to‐substrate ratio of 4%, pH value of 7.8 and reaction temperature of 57 °C, which was in agreement with the predicted value (40.11% and 74.83%, respectively) estimated by RSM. The simulated in vitro gastrointestinal digestion (GID) dramatically modified molecular weights distribution, increased peptide (<3 kDa) concentration and highly retained antioxidant activity of SPPH, indicating potentially utilisation of SPPH as a functional supplement in food system.     

Enhancement of antioxidant activity,total phenolic and flavonoid content of black soybeans by solid state fermentation with Bacillus subtilis BCRC 14715

In the present study, a solid state fermentation of black soybeans with Bacillus subtilis BCRC 14715 was performed. The effect of fermentation on the changes of total phenolic and flavonoid content and antioxidant activities including 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect, and Fe²⁺-chelating ability exerted by various solvent (water, 80% methanol, 80% ethanol, 80% acetone) extracts of black soybeans was examined. It was found that fermentation enhanced the total phenolic and flavonoid content as well as antioxidant activity of the black soybean extract. Among the various extracts examined, the acetone extract of fermented black soybeans showed the highest total phenolic and flavonoid content. The acetone extract and the methanol extract of fermented black soybeans showed the highest DPPH free radical-scavenging effect and Fe²⁺-chelating ability, respectively. Analysis of extraction yields showed that the active principle associated with the DPPH radical-scavenging effect was most efficiently extracted from black soybeans using water, regardless of fermentation. Water and methanol effectively extract the Fe²⁺-chelating principles from non-fermented and fermented black soybeans, respectively.     

Antioxidant,enzyme inhibitory and antiproliferative activity of polyphenolic‐rich fraction of commercial dry ginger powder

Polyphenolic‐rich fraction obtained from locally produced dry ginger powder in Brahmaputra valley, India, and commercially available dry ginger (Zingiber officinale) rhizome powder consisted of [6]‐gingerol (41.9%), [6]‐shogaol (24.3%), 1‐dehydro‐6‐gingerdione (8.6%), [8]‐gingerol (7.2%), [10]‐gingerol (5.1%), [6]‐paradol (5.9%) and [4]‐gingerol (3.6%). Traces of methyl‐[6]‐gingerol and methyl‐[8]‐gingerol (both at 1.8%) were also detected. The fraction exhibited high antioxidant capacity [total phenolics (TP), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC) and cellular antioxidant activity (CAA assay)], effectively inhibited isolated digestive enzymes (α‐glucosidase, pancreatic lipase and angiotensin converting enzyme) and inhibited the proliferation of colon (HT29; IC₅₀ of 1.06 ± 0.02 mg mL^?1) and gastric (AGS IC₅₀ of 1.29 ± 0.03 mg mL^?1) adenocarcinoma cells, without affecting the proliferation of their nontransformed counterparts (IC₅₀ > 2.0 mg mL^?1). This case study demonstrates that locally produced and commercially available dry ginger powder from Brahmaputra valley, India, retains numerous food components that may enhance human health.     

Pharmacological activities of brown seaweed Sargassum wightii (Family Sargassaceae) using different in vitro models

Recently a great deal of interest has been developed towards natural bioactive components from seaweeds as functional food ingredients. Antioxidant, anti-inflammatory, antidiabetic, and antihypertensive activities of ethyl acetate:methanol and chloroform solvent fractions of the brown seaweed Sargassum wightii were evaluated using different in vitro systems. The ethyl acetate:methanol fraction registered greater Fe²⁺ ion chelating ability (IC₅₀ 0.52 mg/ml), and were effective in stabilizing the 2,2-azino-bis-3-ethylbenzothiozoline-6-sulfonic acid (IC₅₀ 0.82 mg/mL), and 1,1-diphenyl-2-picryl hydrazil radicals (IC₅₀ 0.32 mg/mL) than those derived from chloroform solvent fractions. The chloroform solvent fraction showed greater angiotensin converting enzyme-I inhibitory activity (IC₅₀ 0.084 mg/mL), while the ethyl acetate:methanol fraction exhibited greater anti-COX-1, 2, and 5-LOX (IC₅₀ 0.03-0.05 mg/mL) and DPP-4 inhibitory (IC₅₀ ~ 0.013 mg/mL) properties. A significant co-linearity was recorded between target bioactive properties and the electronegative groups appeared in the downfield space of the nuclear magnetic resonance spectra of the ethyl acetate:methanol and chloroform solvent fractions from S. wightii.     

红曲甜米酒生产过程中红曲色素稳定性研究

通过固态发酵的方法,制备红曲米,并从中提取出天然红曲色素。以色价为指标,研究光照、温度、受热时间及金属离子对红曲色素稳定性的影响。结果表明:光照条件对红曲色素稳定性影响的大小顺序为日光紫外灯避光处,其中,日光对红曲色素稳定性的影响最为明显;另外随着温度的升高,红曲色素的稳定性越来越差,加热时间越长,色价损失越大;金属离子中,Fe~(3+)对红曲色素的影响最大,而Cu~(2+)和Zn~(2+)影响不显著。     

Phenolics as antioxidants in garlic (Allium sativum L., Alliaceae)

The antioxidant activities of polar fractions of mature garlic bulbs and immature plants in four different model systems are presented. Antioxidant activity was evaluated as free radical-scavenging capacity (RSC), together with the effect on lipid peroxidation (LP). RSC was assessed by measuring the scavenging activity of garlic extracts on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide. Effects on LP were evaluated by following the activities of examined garlic extracts in Fe²⁺/ascorbate and Fe²⁺/H₂O₂ systems of induction. Investigated extracts reduced the DPPH radical formation (IC₅₀ ranging from 1.03 to 6.01 mg/ml) and neutralised H₂O₂ (IC₅₀ ranging from 0.55 to 2.01 mg/ml) in a dose-dependent manner. Strong inhibition of LP in both systems of induction was observed for all tested garlic extracts. Various levels of phenolics (0.05–0.98 mg gallic acid equivalents/g of dry extract) and flavonoid aglycones (4.16–6.99 μg quercetin equivalents/g of dry extract) in the investigated extracts of garlic could explain the obtained differences in these results only partially.     

Antioxidant properties of polyphenol-rich cocoa products industrially processed

Fermentation and roasting are the main causes of polyphenol degradation during the process for obtaining cocoa products. In the present study, a process for obtaining polyphenol-rich cocoa products on an industrial scale is described. The process avoids the fermentation and roasting steps and includes a step for the inactivation of the enzyme Polyphenol Oxidase (PPO), which helps preserve the polyphenol content present in the raw cocoa bean. In addition, our study evaluates the antioxidant capacity and characterizes the flavonoid profile of the polyphenol-rich cocoa products obtained from the natural polyphenol-rich cocoa cake. Using different protocols, we have obtained three cocoa extracts with high polyphenol content, namely extracts A (167 mg/g), B (374 mg/g) and C (787 mg/g). The scavenging capacity of the extracts was measured as their ability to bleach the stable radicals DPPH and ABTS⁺ while their antioxidant effect was evaluated with the FRAP assay. The results for A, B and C in the DPPH test expressed as Trolox equivalent (μmol)/mg dry weight of extract were 0.2, 1.4 and 3.0, respectively; in the ABTS test the results were 1.0, 4.7 and 9.8. The antioxidant capacity expressed as ascorbic acid equivalent (μmol)/mg dry weight of each product were 17.2, 76.1 and 207.7, respectively. The scavenging properties of cocoa powder against the superoxide anion, H₂O₂, HClO, and peroxynitrite were also determined. The IC₅₀ (μg/mL) values in the hypoxanthine/xanthine oxidase test were 77.5, 12.3 and 10.3, for A, B and C, respectively, while as an HOCl scavenger the IC₅₀ (μg/mL) values were 225.4, 73.2 and 21.5. As a peroxynitrite anion scavenger, only extract C had a relevant effect, with IC₅₀ (μg/mL) values of 76.1 or 110.0 in the absence or presence of bicarbonate. None of the extracts tested showed activity in the hydrogen peroxide test, but B and C significantly increased the deoxyribose degradation in the absence of ascorbate. Likewise, none of the extracts inhibited the ferrous or copper chelating activity at 100 μg/mL, but they inhibited the lipid peroxidation in brain homogenates and human plasma through non-enzymatic generation systems, with extract C giving the best IC₅₀ (μg/mL) values: 17.4 and 8.1 against lipid peroxidation in brain homogenates and human plasma, respectively. In conclusion, if the extractive protocol is well characterized, defined and optimized, cocoa could constitute a source of polyphenols for enriching foods, nutraceuticals and alimentary supplements.     

Enzymatic hydrolysis of hemp (Cannabis sativa L.) protein isolate by various proteases and antioxidant properties of the resulting hydrolysates

Enzymatic hydrolysis of hemp protein isolate (HPI) by six proteases (alcalase, flavourzyme, neutrase, protamex, pepsin and trypsin) and antioxidant activities of the resulting hydrolysates, obtained for 2 and 4 h were investigated. The yield of trichloroacetic acid (TCA)-soluble peptides (Y_sp), protein composition and surface hydrophobicity (H_o) of the hydrolysates were evaluated. The results showed that the hydrolysates exhibited varying DPPH radical scavenging (with lowest IC₅₀, ∼2.3 mg/mL) and Fe²⁺⁺ chelating (with lowest IC₅₀ of 1.6–1.7 mg/mL) abilities and reducing power (with highest absorbance at 700 nm of 0.31–0.35), depending on their Y_sp and H_o values. The DPPH radical scavenging and Fe²⁺⁺ chelating abilities of the hydrolysates were positively correlated with their Y_sp or H_o values. The results suggest that enzymatic hydrolysis can be used as an effective technique to produce high value-added products of hemp proteins.     

Antioxidant and melanogenesis‐inhibitory activities of collagen peptide from jellyfish (Rhopilema esculentum)

BACKGROUND: Jellyfish collagen was hydrolysed with trypsin and properase E, and jellyfish collagen peptide (JCP) was purified from the enzymatic hydrolysate using ion exchange chromatography and gel filtration. The antioxidant activity of JCP in a linoleic acid emulsion system, its superoxide anion‐ and hydroxyl radical‐scavenging activities and its copper‐chelating ability were evaluated in vitro. Initial investigations of JCP's ability to inhibit melanogenesis were carried out using cultured B16 melanoma cells. RESULTS: The molecular weight distribution of JCP was from 400 to 1200 Da. Amino acid analysis showed that JCP was rich in Gly, Pro, Ser, Ala, Glu and Asp and had a total hydrophobic amino acid content of 384.2 g kg^?1. JCP showed high antioxidant activity (IC₅₀147.8 µg mL^?1), superoxide anion‐scavenging activity (IC₅₀21.9 µg mL^?1), hydroxyl radical‐scavenging activity (IC₅₀16.7 µg mL^?1) and copper‐chelating ability (IC₅₀88.7 µg mL^?1) in vitro. It also significantly inhibited intracellular tyrosinase activity, decreased melanin content and enhanced glutathione synthesis (P < 0.05). Furthermore, JCP decreased intracellular cAMP levels and suppressed tyrosinase mRNA expression. CONCLUSION: Based on the results of this study, JCP exerts anti‐melanogenic actions via its antioxidant properties and copper‐chelating ability. JCP could be used as a natural skin‐lightening agent in the medicine and food industries. Copyright © 2009 Society of Chemical Industry     

Antioxidant properties of methanolic extracts from monascal adlay

Both the fungus Monascus sp. and adlay possess functional components effective in improving human health. The fungus was inoculated into adlay and a new product was produced after the colonization of fungal mycelia. Our objective was to evaluate the antioxidant properties of methanolic extracts from inoculated products [monascal polished adlay (MPA) and monascal dehulled adlay (MDA)] as compared to uninoculated products [polished adlay (PA) and dehulled adlay (DA)]. With regard to EC₅₀ values (mg extract ml⁻¹) of methanolic extracts, antioxidant activities were excellent and in the descending order of MDA (0.05) ? MPA (0.75) > DA (0.83) ? PA (6.35). Effectiveness in reducing powers was in a descending order of MPA (0.78) > MDA (1.53) ? PA (13.24) ∼ DA (13.67 mg ml⁻¹). Scavenging abilities on 1,1-diphenyl-2-picrylhydrazyl radicals and chelating abilities on ferrous ions were in the descending order of MPA > MDA > DA > PA. Total phenols were the major naturally occurring antioxidant components found. Overall, monascal adlay products displayed higher antioxidant activity, reducing power, scavenging and chelating abilities and higher in total phenol content than uninoculated adlay products.     

Digestibility and Pasting Properties of Rice Starch Heat‐Moisture Treated at the Melting Temperature (Tm )

Non‐waxy and waxy rice starches adjusted to 20% moisture (wet based, w.b.) were heated in a differential scanning calorimeter to determine the optimum parameters for producing slowly digestible starch (SDS). Starches heated to the temperature of melting (T_m) and held for 60 min in the calorimeter showed a slow digestibility compared to unheated samples. Digestibility decreased by 25 and 10%, respectively, for non‐waxy and waxy rice starches relative to non‐treated starches. Heat‐moisture treatment of waxy corn, non‐waxy corn and wheat starches at the T_m determined for non‐waxy rice starch did not result in significant decreases in digestibility. For waxy rice starches heat‐treated in microwave or conventional ovens at the T_m , there were slight but significant increases in digestibility of the treated starches compared to non‐treated starches at all incubation times. Digestibility was higher for starches heated for 30 min than for 60 min. Non‐waxy rice starches did not show any significant changes in digestibility. Heat‐moisture treatment at the T_m and the holding time of sample at that temperature in a differential scanning calorimeter were found to be significant to the formation of slowly digestible heat‐moisture treated starch.     

Characteristics and antioxidant capacities of five hawthorn wines fermented by different wine yeasts

Different yeast strains can influence the characteristics and active constituents of hawthorn wines. Hawthorn wines were produced using five different yeasts and characterized in terms of their profiles of typical properties and antioxidant capacities. The wine antioxidant capacities of 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), 2′‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulfonic acid, superoxide anion (O₂ · ^–) scavenging activities and ferric reducing antioxidant power (FRAP) were determined. It was found that the general wine compositions showed the expected variations. Except for yeast Lalvin W15 all of the yeasts exhibited good sugar‐utilizing ability and alcohol production. Yeast Lalvin 71B exhibited an excellent fermentation capability. Hawthorn wine fermented by yeast Lalvin 71B had the lowest residual sugar, titratable acidity and colour density and the highest alcohol content. SIHA Active Yeast 3 had good performance in respect to oxidation resistance. The highest content of anthocyanins and polyphenols in the wine was found with hawthorn wine fermented by SIHA Active Yeast 3, and this wine contained the highest antioxidant activity as determined by the DPPH assay, O₂ · ^– assay and FRAP. Statistical analysis indicated that pH value was significantly correlated with colour density (?0.954**) and alcohol content (0.905**) in the hawthorn wines. There was a strong positive correlation between the polyphenol content and the antioxidant activity as determined by the DPPH (0.915**) and FRAP (0.914**) assays, respectively. Copyright © 2013 The Institute of Brewing & Distilling.     

Antioxidant and free radical scavenging potential of Achillea santolina extracts

The antioxidative activities of hydroalcoholic extract of Achillea santolina were investigated employing various established in vitro systems including total antioxidant activity in linoleic acid emulsion system, 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide and hydroxyl radicals scavenging, reducing power, and inhibitory effect on protein oxidation as well as the inhibition of Fe²⁺/ascorbate induced lipid peroxidation in rat liver homogenate. Total phenolic and flavonoid content of A. santolina extract (ASE) was also determined by a colorimetric method. The results revealed that ASE has notable inhibitory activity on peroxides formation in linoleic acid emulsion system along with concentration-dependent quenching of DPPH and superoxide radicals. Furthermore, the extract showed both nonsite-specific (Fe²⁺ + H₂O₂ + EDTA) and site-specific (Fe²⁺ + H₂O₂) hydroxyl radical scavenging suggesting potent hydroxyl radical scavenging and chelating ability for iron ions in deoxyribose degradation model. A linear correlation between ASE and the reducing power was also observed (r² = 0.9981). ASE prevents thiobarbituric acid reactive substances formation in Fe²⁺/ascorbate induced lipid peroxidation in rat liver tissue in a dose-dependent manner. Moreover, free radical induced protein oxidation was suppressed significantly by the addition of ASE over a range of concentration. These results clearly demonstrated that A. santolina extract possess a marked antioxidant activity.     

In vitro inhibitory effects of cranberry bean (Phaseolus vulgaris L.) extracts on aldose reductase, α‐glucosidase and α‐amylase

The in vitro inhibitory activities of different seed extracts prepared from cranberry bean mutant SA‐05 and its wild‐type variety Hwachia against aldose reductase, α‐glucosidase and α‐amylase were examined. The results indicated that the polyphenolics‐rich extracts obtained using 800 g kg^?1 methanol and 500 g kg^?1 ethanol demonstrated inhibitory activities against aldose reductase (IC₅₀ of 0.36–0.46 mg mL^?1) and α‐glucosidase (IC₅₀ of 1.32–1.94 mg mL^?1). The 500 g kg^?1 ethanol extracts also showed α‐amylase inhibitory activities (IC₅₀ of 70.11–80.22 μg mL^?1). Subsequent extracts, prepared further with NaCl and H₂O from precipitates of 800 g kg^?1 methanol or 500 g kg^?1 ethanol extracts, exhibited potent α‐amylase inhibitory activities (IC₅₀ of 17.68–38.68 μg mL^?1). A combination of 500 g kg^?1 ethanol extraction plus a subsequent H₂O extraction produced highest polyphenolics and α‐amylase inhibitors. The SA‐05 α‐amylase inhibitor extracts showed greater inhibitory activities than that of Hwachia. Thus, cranberry bean mutant SA‐05 is an advantageous choice for producing anti‐hyperglycaemic compounds.