Antidiabetic Functional Foods Research Articles

Upregulatory action of antioxidative genes potentiates Capsicum chinense Jacq as an antidiabetic functional food evident in biochemical, histopathological, and network pharmacological impacts

This research characterized the organic extracts of Capsicum chinense by GCMS and LCMS analyses and investigated their antidiabetic potentials in a fructose-fed streptozotocin (STZ)-induced model. The organic extracts were found to display a promising in vitro inhibition of α-amylase and α-glucosidase and in vivo decrease of serum glucose levels, ALP, ALT, AST, creatinine, uric acid, and lipid levels. They upregulated the antioxidative CAT, SOD1, GPx, and PFK1 gene expressions and restored the pancreas, liver, and kidney architectures. Multitarget interactions of C. chinense metabolites forcibly modulated the AKT1 and PIK3R1 proteins demonstrating the prospective functional food potential of C. chinense.

High temperature lacto-fermentation improves antioxidant and antidiabetic potentials of Lithuanian red beetroot

Diabetes is becoming a global pandemic and therefore calls for diverse therapeutic strategies for mitigating the disease. In this study, lactic acid bacteria isolated from Lithuanian traditional fermented foods were screened for β-Glucosidase activity and were used to ferment beetroot to develop an antidiabetic product. After fermentation, LAB PN39MY (also referred to as PN39) fermented samples demonstrated the strongest DPP-IV and α-Glucosidase inhibitory abilities of 50.0 ± 3.5% and 80.5 ± 5% respectively as well as the highest antioxidant capacity of 0.69 ± 0.04 mmol/L relative to all the other samples. Varying the fermentation conditions revealed that fermenting beetroot with PN39 at 45 °C for 72 h yielded the strongest DPP-IV and α-Glucosidase inhibition of 87.45% and 80.5 ± 5.3% respectively and increased the antioxidant capacity to 1.46 ± 0.01 mmol/L. Whole genome sequencing analysis of PN39 revealed the strain to be Latilactobacillus curvatus. HPLC-MS analysis of PN39 fermented samples showed that the fermentation process generated high levels of dihydromyricetin (an antidiabetic flavonoid) which was absent in unfermented beetroot. Results from this study indicate that fermenting beetroot with Latilactobacillus curvatus PN39 at 45 °C for 72 h would be an effective method for developing antidiabetic functional foods.

SHREDDED TUNA FORTIFIED WITH BANANA BLOSSOMS AS AN ANTI-DIABETIC FOOD CANDIDATE: AN INVESTIGATIONAL IN SILICO STUDY

Fish shredded is nutritious and has a soft texture, less stringy than shredded beef. The compounds in tuna shredded fortified with banana blossoms and their potential as antidiabetic are not yet known. The purpose of this study was to identify phytochemical bioactive compounds in tuna shredded fortified with banana blossoms and to study its potential as an antidiabetic functional food in silico. The 70% fortified tuna shreds were extracted using hexane, followed by ethyl acetate and finally using methanol. The methanol filtrate was evaporated to obtain methanol extract of shredded fish and analyzed using LC-HRMS. Phytochemical compounds were analyzed for antidiabetic potential in silico using Open Babel GUI software version 2.4.1, PyRx 0.8 (The scrips Research Institute), PyMOL™ 1.7.4.5, and Discovery Studio Visualizer (2021). The methanol extract of banana heart fortified tuna fish contained 32 compounds. The results of docking the compounds against the α-glucosidase receptor showed that the compound that had a lower or the same binding affinity with acarbose (-8.00 Kcal/mol) and native ligand (-6.00 Kcal/mol) was flurandrelonide (-9.40 kcal/mol), Quercetin-3β-D-glucoside (-9.30 kcal/mol), sakuranetin (-8.80 kcal/mol), curcumin (-7.70 kcal/mol), ar-turmerone (-7.20 kcal/mol), nootkatone (-7.20 kcal/mol), and ferulic acid (-6.90 kcal/mol). The lower the binding affinity value, the stronger the inhibition of α-glucosidase. Phytochemical compounds in shredded tuna fortified with banana blossoms that may act as antidiabetic agents through in silico α-glucosidase inhibition are flurandrelonide, quercetin-3β-glucosidase, sakuranetin, curcumin, ar-turmerone, and ferulic acid.

Chemical characterization of the antioxidant and α-glucosidase inhibitory active fraction of Malus transitoria leaves

Chinese Tibetan tea made from the tender leaves of Malus transitoria is a widely consumed health drink, but there are few reports on its chemical composition and biological activity. In this study, we found that a 50% ethanol extract of M. transitoria had good antioxidant and α-glucosidase inhibitory activities in vitro. Guided by in vitro bioassays, chromatographic separation and purification were conducted, and the most active fraction in M. transitoria was determined. UPLC-Orbitrap-MS/MS was used to further quickly and comprehensively characterize the chemical composition. Library searches, MS/MS fragmentation patterns of two isolated reference compounds, and bibliography were used to annotate 81 compounds, of which 2 were new compounds, and 79 were identified from M. transitoria for the first time. This study provides a scientific basis for the development of antioxidant and anti-diabetic functional foods from M. transitoria.

Identification and molecular docking of novel α-glucosidase inhibitory peptides from hydrolysates of Binglangjiang buffalo casein

Binglangjiang buffalo is a new type of river buffalo discovered in Tengchong of Yunnan Province, China, with rich protein in milk. In this study, we isolated novel α-glucosidase inhibitory peptides from the buffalo casein hydrolyzed by Dregea sinensis protease using RP-HPLC. A total of 26 peptides in the active fraction were identified by LC-MS/MS, mainly belonging to αs1-CN, αs2-CN, and β-CN. Based on bioinformatics analysis, four peptides with potential α-glucosidase inhibitory activity were selected for chemical synthesis and activity verification. The four synthetic peptides exhibited α-glucosidase inhibitory activity and had IC50s of 470.492 ± 3.086 μmol/L (P3), 498.040 ± 1.829 μmol/L (P2), 503.635 ± 3.269 μmol/L (P1), and 542.502 ± 1.995 μmol/L (P4). Through molecular docking, we found that these four peptides may occupy the potential catalytic active sites (Arg387, Arg428, Arg727, Arg801, Arg799, and Trp710) of α-glucosidase through forming hydrogen bonds and hydrophobicity, thus hindering the formation of complex and glycosylation between α-glucosidase and substrate. Screening α-glucosidase from buffalo casein hydrolysates will provide insights for further study on the antidiabetic mechanism of the peptides and further development of antidiabetic functional food.

Pomegranate peel-derived punicalagin: Ultrasonic-assisted extraction, purification, and its α-glucosidase inhibitory mechanism

The pomegranate peel is a by-product of pomegranate fruit rich in polyphenols. In this study, pomegranate peel polyphenols were explored using LC-MS/MS, and punicalagin was the most abundant compound. The highest yield (505.89 ± 1.73 mg/g DW) of punicalagin was obtained by ultrasonic-assisted extraction (UAE) with the ethanol concentration of 53%, sample-to-liquid ratio of 1:25 w/v, ultrasonic power of 757 W, and extraction time of 25 min. Punicalagin was further purified by the macroporous resin D101 and prep-HPLC, reaching the purity of 92.15%. The purified punicalagin had the IC50 of 82 ± 0.02 µg/mL against α-glucosidase, similar to the punicalagin standard with IC50 of 58 ± 0.014 µg/mL, both exhibiting a mixed inhibitory mechanism. Molecular docking further revealed that a steric hindrance with the intermolecular energy of −7.99 kcal/mol was formed between punicalagin and α-glucosidase. Overall, pomegranate peel is a promising source of punicalagin to develop anti-diabetic functional foods.

The Effectiveness of the “Panjang” Poffertjes Consumption on Blood Glucose Level

Background: Fragrant pandan leaf extract (Pandanus amayllifolius Roxb.) has pharmacological activity as an anti-diabetes, while sweet corn is believed to be a staple food or snack for people with diabetes mellitus. Thus, the foods could be used as an alternative to anti-diabetic functional food. Objective: This study aims to investigate the effectiveness of “Panjang” poffertjes consumption with the addition of pandan leaves extract and sweet corn on the blood glucose level. Methods: This study employs a randomized controlled trial approach with the pre-and post-test design. The data collected on the value of the glycemic index, glycemic load, and the results of 2 hours postprandial (pp) blood sugar level examination after consuming two Poffertjes formulas. The glycemic index (GI) was calculated by employing incremental area under the blood glucose response curve method for ten subjects and a 2-hour postprandial (pp) blood sugar level examination in 25 subjects with the range age between 18-24 years, with normal nutritional status (BMI = 18.58-23.88), 100% had no history of diabetes, did not smoke or alcohol and were not allergic to the tested food ingredients. Results: the results show that the glycemic index of control Poffertjes obtained a value of 71.88 (high category), and “Panjang” Poffertjes got 52.82 (low category). The glycemic load of control Poffertjes obtained a value of 12.78 (medium category), while “Panjang” Poffertjes attained a value of 6.37 (low category). The difference in the average reduction in blood glucose with the intervention poffertjes was 11.08 mg/dl. Conclusion: the provision of “Panjang” poffertjes has a significant effect on the decrease in twohour postprandial blood glucose level.

Antidiabetic activity screening and nmr profile of vegetable and spices commonly consumed in Indonesia

Apart from their nutritional value, vegetables and spices were empirically known to have functional properties such as antioxidant and antidiabetic activity. However, scientific evidence of these health effects is limited. In our effort to find potent raw material for antidiabetic functional food development, α-glucosidase inhibition and antioxidant activity of 15 Indonesian vegetables and spices methanolic extracts were screened. Their phytochemical profiles were assessed by determining total phenolic content (TPC) and 1H NMR fingerprinting. The results showed that the Syzygium polyanthum, Pluchea indica, Etlingera elaitor, and Cosmos caudatus had the highest GIA (IC50 11.76 ± 0.32, 12.17 ± 0.18, 53.13 ± 2.87, and 61.33 ± 1.21 μg/ml, respectively). The AA and TPC of the four samples were also higher than the others. The 1H NMR profiles of the active samples were different from the non-active samples mainly in the aromatic region. Further observation of the spectra revealed that caffeoylquinic derivatives and esculetin were identified in P. indica; while gallic acid, syringic acid, and myricetin were identified in S. polyanthum. These compounds were known to have antidiabetic activity through different mechanisms.

Opuntia dillenii (Ker Gawl.) Haw., Seeds Oil Antidiabetic Potential Using In Vivo, In Vitro, In Situ, and Ex Vivo Approaches to Reveal Its Underlying Mechanism of Action.

Opuntia dillenii Ker Gawl. is one of the medicinal plants used for the prevention and treatment of diabetes mellitus (DM) in Morocco. This study aims to investigate the antihyperglycemic effect of Opuntia dillenii seed oil (ODSO), its mechanism of action, and any hypoglycemic risk and toxic effects. The antihyperglycemic effect was assessed using the OGTT test in normal and streptozotocin (STZ)-diabetic rats. The mechanisms of action were explored by studying the effect of ODSO on the intestinal absorption of d-glucose using the intestinal in situ single-pass perfusion technique. An Ussing chamber was used to explore the effects of ODSO on intestinal sodium-glucose cotransporter 1 (SGLT1). Additionally, ODSO’s effect on carbohydrate degrading enzymes, pancreatic α-amylase, and intestinal α-glucosidase was evaluated in vitro and in vivo using STZ-diabetic rats. The acute toxicity test on mice was performed, along with a single-dose hypoglycemic effect test. The results showed that ODSO significantly attenuated the postprandial hyperglycemia in normal and STZ-diabetic rats. Indeed, ODSO significantly decreased the intestinal d-glucose absorption in situ. The ex vivo test (Ussing chamber) showed that the ODSO significantly blocks the SGLT1 (IC50 = 60.24 µg/mL). Moreover, ODSO indu\\ced a significant inhibition of intestinal α-glucosidase (IC50 = 278 ± 0.01 µg/mL) and pancreatic α-amylase (IC50 = 0.81 ± 0.09 mg/mL) in vitro. A significant decrease of postprandial hyperglycemia was observed in sucrose/starch-loaded normal and STZ-diabetic ODSO-treated rats. On the other hand, ODSO had no risk of hypoglycemia on the basal glucose levels in normal rats. Therefore, no toxic effect was observed in ODSO-treated mice up to 7 mL/kg. The results of this study suggest that ODSO could be suitable as an antidiabetic functional food.

Diospyros lotus L. fruit: A potential antidiabetic functional food targeting intestinal starch hydrolysis

Post-meal hyperglycaemia is considered a prominent therapeutic target to attenuate the progression of diabetes and its associated complications. The present study identified fruit extract of Diospyros lotus Linnaeus, of the Ebenaceae family, as an inhibitor of starch digestion through the inhibition of both alpha amylase and alpha glucosidase. The extract inhibits porcine and human pancreatic amylase with IC50 values of 82.5±2.0 and 130.4±24 μg/ml respectively. The inhibition of intestinal sucrase and maltase activity was however considerably weaker. In vitro hydrolysis of solubilised potato starch into glucose yielded comparable inhibition kinetics for 100 μg/ml D. lotus L. extract and 3.5 μM acarbose. Screening the major phenolic constituents revealed that quercetin and myricetin were the strongest alpha amylase inhibitors. D. lotus L. extract showed strong antioxidant activity; however, this provided no meaningful protection against 2-deoxy-ribose induced oxidative stress in INS-1 cells. Taken together these findings identify D. lotus L. fruit as a multi-component functional food with potential to dampen the onset and development of diabetes through the inhibition of post meal hyperglycaemia.

A new high-performance liquid chromatographic method for the quality control of bioconverted Mori Folium extracts with appropriate marker compounds related to antidiabetes

A HPLC method was developed to assess the enhanced bioactivity of bioconverted Mori Folium (MF) extract and to apply a quality-control system. Liquid-liquid extraction was applied to observe changes in chemical composition through enzymatic bioconversion. The ethyl acetate layer was used for quality control of the anti-diabetic functional MF product. A high-performance liquid chromatography method was developed to analyze five marker compounds (syringaldehyde, trans-caffeic acid, morin 3-O-β-D-glucopyranoside, astragalin, and moracin M 3′-O-β-glucopyranoside) within 60 min. Optimized sample preparation was sonication for 44 min and a water-to-material ratio of 102.5 mL/g by response surface methodology. Comparing MF water extract, trans-caffeic acid and syringaldehyde contents were increased 1.89 times and 2.70 times at Viscozyme-bioconverted material by applying the developed method. This HPLC method can be used to control the quality of bioconverted MF based on suitable bioactive markers and also applied to develop anti-diabetic functional foods containing Mori Folium.

Thermoase-hydrolysed pigeon pea protein and its membrane fractions possess in vitro bioactive properties (antioxidative, antihypertensive, and antidiabetic).

Enzymatic hydrolysis can liberate bioactive peptides from protein materials, thus, pigeon pea was hydrolysed using thermoase. Crude hydrolysate (PPHT) was subjected to ultrafiltration using different molecular weight cutoffs to collect <1, 1-3, 3-5, 5-10, and >10kDa peptide fractions. Fractions were analysed for in vitro antioxidative, antihypertensive, and antidiabetic properties. The peptide fractions had stronger DPPH• scavenging and renin inhibition when compared to PPHT. In contrast, ACE inhibition was stronger for the PPHT and <1kDa peptide fraction while activity decreased as peptide size increased. The <1kDa peptide also showed significantly stronger ferric reducing antioxidant power, OH• scavenging and inhibition of linoleic acid oxidation when compared to PPHT. α-amylase and α-glucosidase were inhibited by all the peptide fractions, though the 3-5 and >10kDa had higher values. We conclude that the PPHT and peptide fractions could serve as potential ingredients to formulate antihypertensive and antidiabetic functional foods and nutraceuticals. PRACTICAL APPLICATIONS: Oxidative stress promotes the generation of free radicals, which have a significant impact in the pathogenesis of human chronic diseases such as cardiovascular impairment, cancer, and diabetes. Peptides generated from enzymatic hydrolysis of proteins have been identified to impart beneficial health effects. In this work, we showed that a thermoase digest of pigeon pea protein as well as the fractionated peptides had strong antioxidant properties in addition to exhibiting inhibitory activities against renin and angiotensin converting enzyme, the main therapeutic targets for antihypertensive agents. The peptide products also inhibited α-amylase and α-glucosidase activities, providing potential ingredients that can be used to formulate antidiabetic functional foods.

Oleanane Triterpenoids from the Leaves of Gymnema inodorum and Their Insulin Mimetic Activities.

During an effort to find insulin mimetic compounds, the leaves of Gymnema inodorum were shown to have a stimulatory effect on glucose uptake in 3T3-L1 adipocyte cells. Bioassay-guided fractionation on a 70% ethanol extract of G. inodorum was applied to yield two new (1 and 2) and two known (8 and 9) oleanane triterpenoids with a methyl anthranilate moiety together with five further new oleanane triterpenoids (3-7). The chemical structures of all isolates were determined based on their spectroscopic data, including IR, UV, NMR, and mass spectrometric analysis. The isolated compounds (1-9) were determined for their stimulatory activities on glucose uptake in differentiated 3T3-L1 adipocyte cells using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a fluorescent-tagged glucose probe. Three compounds (3, 5, and 9) showed stimulatory effects on the uptake of 2-NBDG in 3T3-L1 adipocyte cells. Chemicals with a methyl anthranilate moiety have been considered as crucial contributors of flavor odor in foods, and quantitative analysis showed the content of compound 8 to be 0.90 ± 0.01 mg/g of the total extract. These results suggest that the leaves of G. inodorum have the potential to be used as an antidiabetic functional food or tea.

Phaseolus lunatus(lima beans) abates Fe2+‐induced hepatic redox imbalance; inhibits intestinal glucose absorption and major carbohydrate catabolic enzymes; and modulates muscle glucose uptake

The antioxidative and antidiabetic effects of the aqueous extract of Phaseolus lunatus were investigated in vitro and ex vivo. The seeds were subjected to aqueous extraction, after defatting with n-hexane. The extract (15, 30, 60, 120, 240 µg/ml) showed significant (p < 0.05) free radical scavenging and enzyme inhibitory activities in vitro. It significantly (p < 0.05) elevated glutathione level with concomitant depletion of malondialdehyde level as well as increased superoxide dismutase and catalase activities in rat liver. Fe2+-induced hepatic DNA fragmentation was also significantly (p < 0.05) suppressed. The extract significantly inhibited intestinal glucose absorption and increased muscle glucose uptake with and without insulin. The inhibitory activities and reversion of hepatic redox imbalance, as well as inhibition of intestinal glucose absorption and increased muscle glucose uptake by P. lunatus suggest an antihyperglycemic and antioxidative effect. These can be ascribed to the synergistic effect of the phytochemicals and amino acids identified in the extract. Practical applications Lima beans (Phaseolus lunatus) is among the many underutilized legumes with reported nutritional benefits. It is utilized locally in Nigeria in treating and managing diabetes and its complications, but without any scientific proof. The ability of the legume to inhibit digestive enzymes linked to postprandial blood glucose spike, as well as inhibition of intestinal glucose absorption and increased muscle glucose uptake substantiates its antidiabetic folkloric uses. The amino acid constituents also indicate its nutritional properties. These findings will promote its utilization not only as an antidiabetic functional food but also as a nutritional meal.

THE EFFECT OF HEATING TEMPERATURE ON INHIBITORY ACTIVITY OF MANGROVE RHIZOPHORA MUCRONATA FRUIT EXTRACT TOWARD Α-GLUCOSIDASE

Objectives: The aim of this research was to determine the effect of heating temperature of mangrove Rhizophora mucronata fruit extract toward its inhibition activity of α-glucosidase. Methods: Research method used was an experimental method with the treatment of heating temperature (70°C, 80°C, 90°C, and 100°C) of crude tannin extract of mangrove R. mucronata fruit on inhibition activity toward α-glucosidase. Results: IC50 of unheated extract and extracts that were heated at 70°C, 80°C, 90°C, and 100°C are adalah 3.38 ppm, 2.79 ppm, 2.97 ppm, 3.19 ppm, and 3.52 ppm, respectively. Heating until 100°C only decreased its inhibition activity of α-glucosidase of about 3.87% compared to unheated extract. Mangrove R. mucronata fruit extract contains phytochemical compounds, i.e., alkaloids, saponin, flavonoids, tannin, and terpenoids. IC50 of this extract is lower compared to IC50 of acarbose (antidiabetic medicine), which as IC50 value of 13.27 ppm. Conclusion: Mangrove R. mucronata fruit extract is quite heat resistant and is potential to be an antidiabetic functional food.

A Novel Antidiabetic Food Produced via Solid-State Fermentation of Tartary Buckwheat by L. plantarum TK9 and L. paracasei TK1501.

SummaryDiabetes is a chronic metabolic disease characterized by hyperglycaemia and a number of potential complications that significantly reduce the patient’s quality of life. In this study, we produced an antidiabetic functional food from Tartary buckwheat fermented by Lactobacillus plantarum TK9 and L. paracasei TK1501. The results of an orthogonal experimental design indicated that the three factors with the largest effects on the growth of L. plantarum TK9 and L. paracasei TK1501 in solid-state fermentation (SSF) were in the order: water ratio>inoculum size>time of fermentation. Under the optimal fermentation conditions comprising a 1:1.5 water ratio, 24 h of SSF and a 107 CFU/g inoculum, the Tartary buckwheat fermented by L. plantarum TK9 and L. paracasei TK1501 yielded viable probiotic counts of (2.3±0.7)·109 and (3.3±0.4)·109 CFU/g, respectively. The nutritional potential, as well as antioxidant and antidiabetic properties of ethanolic extracts from fermented Tartary buckwheat were investigated. The highest α-glucosidase inhibitory activity, with an IC50 of 0.51 mg/mL, was present in Tartary buckwheat fermented by L. plantarum TK9. However, Tartary buckwheat fermented by L. paracasei TK1501 had the highest dipeptidyl peptidase IV (DPP-IV) inhibition, with an IC50 of 2.47 mg/mL. Therefore, fermentation by both L. plantarum TK9 and L. paracasei TK1501 has the potential to yield a product that can help regulate the levels of blood glucose as part of a diabetic diet.

Anti-diabetic functional food with wasted litchi seed and standard of quality control

The prevalence of diabetes has become a huge health burden in parts of quality of life and economic cost for overcoming this chronic disease. We followed a bioactivity-guided isolation using α-glucosidase inhibitory assay, four major compounds were isolated, and their structures were elucidated using nuclear magnetic resonance, mass spectrometry, and ultra-performance liquid chromatography quadrupole time of flight mass spectrometry in litchi seed. As a result, the IC50 of α-glucosidase inhibitory assay of the crude extract, sugar-removed layer, pavetannin B2, procyanidin A2, and acarbose was 0.691 μg/mL, 3.686 μg/mL, 0.04 μM, 0.08 μM, and 55.845 μg/mL, respectively. With those compounds, we examined the protein tyrosine phosphatase 1B inhibitory activity. And the IC50 of pavetannin B2, procyanidin A2, and ursolic acid was 450.295, 338.257, and 19.686 μM, respectively. Contents analysis method for bioactive compounds, which can be used in manufacturing for extract preparations, was established. The findings of this study, litchi seed can be a cost-effective medicinal food in terms of recyclable resources in the litchi food industry and as a natural alternative medicine against type-2 diabetes.

Anti-prediabetic effect of rose hip (Rosa canina) extract in spontaneously diabetic Torii rats.

Prediabetes, a high-risk state for developing diabetes showing impaired glucose tolerance but a normal fasting blood glucose level, has an increasing prevalence worldwide. However, no study investigating the prevention of impaired glucose tolerance at the prediabetic stage by anti-diabetic functional foods has been reported. Thus, the present study aimed to evaluate the anti-prediabetic effect of rose hip in a prediabetic rat model. Spontaneously diabetic Torii (SDT) rats were supplemented with hot-water extract of rose hip at a dose of 100 mg kg-1 body weight day-1 for 12 weeks. The results obtained showed that the supplementation of rose hip extract improved impaired glucose tolerance, promoted insulin secretion, preserved pancreatic beta-cell function and suppressed plasma advanced glycation end-products formation of methylglyoxal-derived hydroimidazolone (MG-H1) residue and Nϵ -carboxymethyl-lysine residues (e.g. MG-H1, control: 465.5 ± 43.8 versus rose hip: 59.1 ± 13.0 pmol mg protein-1 , P < 0.05) in SDT rats at the prediabetic stage (12-20 weeks old). The present study provides the first evidence showing that a hot-water extract of rose hip could exert an anti-prediabetic effect in a rat model. © 2017 Society of Chemical Industry.

Biguanide related compounds in traditional antidiabetic functional foods

Biguanides such as metformin are widely used worldwide for the treatment of type-2 diabetes. The identification of guanidine and related compounds in French lilac plant (Galega officinalis L.) led to the development of biguanides. Despite of their plant origin, biguanides have not been reported in plants. The objective of this study was to quantify biguanide related compounds (BRCs) in experimentally or clinically substantiated antidiabetic functional plant foods and potatoes. The corrected results of the Voges–Proskauer (V–P) assay suggest that the highest amounts of BRCs are present in green curry leaves (Murraya koenigii (L.) Sprengel) followed by fenugreek seeds (Trigonella foenum-graecum L.), green bitter gourd (Momordica charantia Descourt.), and potato (Solanum tuberosum L.). Whereas, garlic (Allium sativum L.), and sweet potato (Ipomea batatas (L.) Lam.) contain negligible amounts of BRCs. In addition, the possible biosynthetic routes of biguanide in these plant foods are discussed.

영지버섯, 여주, 쓴메밀 및 혼합 시료의 메탄올 추출물의 생리활성

영지버섯, 여주, 쓴메밀 및 이들 혼합 시료의 70% 메탄올 추출물을 이용하여 생리활성물질(폴리페놀 화합물 및 플라보노이드) 농도와 항산화(DPPH radical 소거 활성, 생체막 지질과산화, Fe/Cu 환원력), <TEX>${\alpha}$</TEX>-glucosidase 저해, tyrosinase 저해 및 항혈전 활성에 대하여 검토하였다. 추출 수율과 폴리페놀 화합물 및 플라보노이드의 함량은 혼합 추출물에서 가장 높았다. 또한 혼합 추출물에서 <TEX>${\alpha}$</TEX>-glucosidase 저해, tyrosinase 저해, 항산화, 환원력 및 항혈전 활성은 혼합 추출물에서 가장 높았으며, 이러한 효과는 처리 농도 의존적 이였다. 이상의 실험 결과에서 영지버섯, 여주, 쓴메밀의 혼합 메탄올 추출물은 폴리페놀 화합물과 플라보노이드를 많이 함유함으로서 높은 <TEX>${\alpha}$</TEX>-glucosidase 저해 및 항산화 활성과 관련성이 높아 보여 항당뇨 건강 기능성식품의 소재 개발에 활용될 가능성이 높아 보인다. The concentrations of bioactive material (polyphenolics and flavonoids) and the biological activities of antioxidative (DPPH [<TEX>${\alpha},{\alpha}'$</TEX>-diphenyl-<TEX>${\beta}$</TEX>-picrylhydrazyl] free radical scavenging activity, peroxidation of rat liver microsome, and Fe/Cu reducing power), <TEX>${\alpha}$</TEX>-glucosidase inhibition, tyrosinase inhibition, and fibrinolytic activity were tested by in vitro experimental models using 70% methanolic extract from Ganoderma lucidum, Momordica charantia, Fagopyrum tataricum and their mixtures. The highest yield and the concentrations of polyphenolics and flavonoids were shown in the mixture extract. Mixture extract was shown to have the highest activities of <TEX>${\alpha}$</TEX>-glucosidase inhibition and tyrosinase inhibition, fibrinolytic, DPPH free radical scavenging, and Fe/Cu reducing power in a concentration-dependent manner. From these results, mixture methanol extract was shown to have the most potent bioactive properties and to contain large amounts of biological materials such as polyphenolics and flavonoids. This mixture could be a good dietary supplement material candidate, such as for antidiabetic functional foods.