022001032 yen, le tran thi hai

VIETNAM NATIONAL UNIVERSITY – HOCHIMINH CITY INTERNATIONAL UNIVERSITY EVALUATING THE ALPHA-GLUCOSIDASE INHIBITON OF THE Artocarpus altilis Fosberg leaves A thesis submitted to The School of Biotechnology, International University In partial fulfillment of the requirements for the degree of B.S inBiotechnology Student name: Le Tran Thi Hai Yen – ID: BTIU08123 Supervisor: Dr Le Thi Ly Dr Hoang Le Son MSc Phung Van Trung February, 2013 EVALUATING THE ALPHA-GLUCOSIDASE INHIBITON OF THE ARTOCARPUS ALTILIS FOSBERG LEAVES Yen T.T.H Lea, Ly T Lea, Son L Hoanga, Trung V Phungb a School of Biotechnology, International University – Vietnam National University in HCMC b Department of Chemistry of Natural Products, Institute of Chemical Technology, Vietnam Academy Science and Technology Corresponding author’s email address: ly.le@hcmiu.edu.vn ACKNOWLEDGEMENT I would like to express my deepest gratitude to my supervisor, Dr Le Thi Ly, for her wide knowledge on Applied Chemistry Her understanding, encouragement and personal guidance have provided a good basis for this thesis I am also deeply grateful to my co-supervisors; Dr Hoang Le Son and MSc Phung Van Trung for their support throughout this work L owe my most gratitude to these instrument officers in Department of Chemistry of Natural Products, Institute of Chemical Technology, Vietnam Academy Science and Technology; Mr Minh, Mr Phat, Miss Be, Miss Hien I wish to express my warm and sincere thanks to my former labmates for their valuable advices and their friendship which I have treasured the most I cannot end thanking my family, and my dearest siblings on whose constant encouragement and patience I have relied throughout my study Friends and colleagues for whom I have great regard, wish to extend my warmest thank to all those who have helped me ABSTRACT This study investigates the effect of Artocarpus altilis (Parkinson) Fosberg leaf extracts on -glucosidase activity Among the extracts tested, Ethyl Acetate extract exhibited a potential -glucosidase inhibitory activity with an IC50 value of 11.38 1.074 (μg/mL) In contrast, the Hexane and Methanolic extracts showed lowest inhibition with the IC50 value in turn 1,099 2.004 and 1,085 1.715 (μg/mL) Extracts were also tested for anti-oxidant activity by 1, 2- Diphenyl-2- picrylhydrazyl (DPPH) assay The E4 fraction of Ethyl Acetate extract had strongest inhibitory activity with the lowest IC50 value 25.39 1.270 (μg/mL) while E17 and E18 had low percentage inhibited DPPH with higher IC50 value 215,970 6.176 and 269,113 4.551 (μg/mL) respectively The phytochemical analysis indicated the varied distribution of tannins, glycosides, saponins, steroids, flavonoids and alkaloid in crude extracts The correlation between the phytochemical analysis and glucosidase activity and DPPH assay suggests that the high content of glycosides, flavonoids and steroids compounds could be involved in exerting -glucosidase activity and DPPH inhibition This study supports the utilisation of Artocarpus altilis (Parkinson) Fosberg leaf in the folk medicine for the better treatment of antidiabeties Keyword: Artocarpus altilis (Parkinson) Fosberg leaves, -glucosidase inhibition, DPPH inhibition I INTRODUCTION For centuries, people have been using herbs for medicinal purposes Medicinal plants have their own historical stake in every early civilization Medicinal plants have been used for centuries as traditionally to treat various types of diseases such as infectious disease and malignancy Artocarpus altilis (Parkinson) Fosberg, originated in the western Pacific, is a widely known food source, but is also commonly used as a folk medicine in Vietnam where it is locally called Sake The plant Artocarpus altilis (Parkinson) Fosberg is belonging to the family Moraceae, 10-15m tall, evergreen Bark grayish brown, thick as showed in Figure Branchlets are 0.5-1.5cm thick Leaves broadly obovate, almost entire with only slight lobing to deeply pinnately lobed with sinuses from 2/3 to 4/5 of the distance from margin to midrib, or deeper Fruits globose to oblong, skin light green; surface smooth to slightly bumpy or spiny with individual disks ranging from areolation [1] Figure 1: the Artocarpus altilis (Parkinson) Fosberg (a) tree and (b) leaf Traditionally, the leaves of Artocarpus altilis (Parkinson) Fosberg are used for the treatment of various kinds of diseases such as liver cirrhosis, hypertension and diabetes [2] Scientifically, some biological activities of the extract of this plant have been reported The acetone extract of the leaves showed an inhibitory effect on 5αreductase activity which might make it useful for the selective treatment of benign prostate hyperplasia and prostate cancer [3] Recently, a study showed the ethylacetate extract of the leaves had cytotoxic effects on some human cancer cell lines, including human lung adenocarcinoma (SPC-A-1 cells), human colon carcinoma (SW-480 cells), and human hepatocellular carcinoma (SMMC-7721 cells) [4] , thus indicating that the extract might be a potential anti-cancer agent In 2011, Vietnamese scientists have isolated three substances are Quercertin (1), Rutin (2), 8-gerany-4,5,7-trihydroxyflavon (3) as can be seen from Figure The results indicated two of Quercetin and Rutin in yellow powder had the ability to reduce the risk of cancer, help prevent heart disease, antioxidant, anti-inflammatory activity, anti-virus, prevention and treatment of Depression bone [6] OH OH HO OH HO O O OH O OH OH OH O O O (1) H 3C (8) O HO O HO HO OH HO OH (2) (3) (9) Figure 2: The structure of (1) Quercertin, (2) Rutin, (3) 8-gerany-4,5,7-trihydroxyflavon In 2007, Lotulung PDN et al dihydroxyphenyl) -3 - [7] isolated a yellow crystalline [8-hydroxy-2-methyl-2 - - (2,4- (4-methyl-3-pentenyl)-2H-1- benzopyran-5-yl]-1-propanone, also known as AC-GF (4) in CH2Cl2 leaves extract as presented in Figure OH O Figure 3: The structure of AC-GF O HO OH (43) (4) Nowadays, the more modern living, the more diseases we have, once of them is diabetes That make we thought to find many ways to treat this disease Carried out this project can give one opportunity to treat it Besides that, folk remedy already using Artocarpus altilis Fosberg leaves for treating diabetes for a long time So, after this study, we can demonstrate the reliability of that folk remedy The main purpose of this study was to prepare the extract from Artocarpus altilis (Paskinson) Fosberg leaves and then determined the -glucosidase inhibition of them II MATERIALS AND METHODS Preparation of extracts[9] The leaves of Artocarpus altilis (Parkinson) Fosberg were collected from Ho Chi Minh City The leaves were washed thoroughly under tap water, shade dried, powdered The powdered leaves were macerated with 96% Ethanol to produce crude extract The crude extract was partitioned with Hexane, Ethyl Acetate and Methanol respectively The Rotary evaporator R200 was used for eliminating solvents The procedure for extract of leaves of Artocarpus altilis (Parkinson) Fosberg can be diagramed in Figure Figure 4: The process of extract leaves Artocarpus altilis (Parkinson) Fosberg The extracts were fractionated by Medium pressure column with silicagel 60 d=0.04-0.063m Testing -glucosidase inhibiton ability a Principles[10] -Glucosidase Assay is designed to measure -glucosidase activity directly in biological samples without pretreatment The improved method utilizes pnitrophenyl- -D-glucopyranoside that is hydrolyzed specifically by α- glucosidase into a yellow colored product (maximal absorbance at 405nm) The rate of the reaction is directly proportional to the enzyme activity p-nitrophenyl--D-glucopyranoside  -D-glucopyranoside + p-nitrophenol -glucosidase Inhibitory activity of the extracts was calculated by the formula: % inhibition = {Absorbance (control) – Absorbance (sample)}*100% Absorbance (control) I%= [A]o – [A]i [A]o *100 % In which: [A]o the average absorption of control [A]i the average absorption of sample IC50 value is defined as the concentration of extract inhibiting 50% of -glucosidase activity under the stated assay conditions In case of significant inhibition, IC50 values were determined by linear regression by fitting to a sigmoid dose-response equation with variable slope All values are represented as Mean ± Standard Deviation b Procedure: - Preparation of test samples as can be seen in Figure 5: Figure 5: The procedure of testing samples - The control (Acarbose) contained all reagents without the tested sample The reactions were conducted in triplicate Antioxidant assay[8] The DPPH radical scavenging activities of the extracts were determined by the method of Blois (1958) with slight modification Initially, mL of methanol solution containing 0.1 mL each of the samples at different concentrations was mixed with mL of 0.15 mM DPPH (dissolved in methanol) The reaction mixture was then incubated for 30 at room temperature The control contained all reagents without the sample, whereas methanol was used as a blank All measurements were performed in triplicate DPPH radical scavenging activity was determined by measuring the absorbance at 490nm and expressed as the inhibition percentage of free radicals by the sample after calculation using the following formula: % inhibition = {Absorbance (control) – Absorbance (sample)}*100% Absorbance (control) I%= [A]o – [A]i [A]o In which: [A]o the average absorption of control [A]i the average absorption of sample *100 % Phytochemical screening[9] The presence of phytochemical compounds in the extract of Artocarpus altilis (Paskinson) Fosberg leaves was tested by the following methods: - Draggendorff’s reagent for Alkaloids - Fehling method for Glycosides - Shaking for Saponins - Ferric chloride for Tanins - Liebermann’s Burchard Test for Steroids - Shibata’s raction for Flavonoids 10 III RESULTS Preparation of extracts Initially, 8kg of Artocarpus altilis (Parkinson) Fosberg leaves were macerated with 96% Ethanol to give 300g of crude extract The crude extract partitioned with different solvents to give 127g of Hexane extract, 85g of Ethyl Acetate extract and 14g of Methanol extract The extracts were fractionated by Medium Pressure Column 12 fractions of Hexane extract, fractions of Ethyl Acetate extract and fractions of Methanol extract were collected From the 8th fraction of Ethyl Acetate extract, after removing the solvent, white powder was obtained The powder was tested by TLC with the solvent system Chloroform: Methanol (9:1) and sprayed 10% Sulfuric acid/ Ethanol The violet-brown color was observed AA02 structure was elucidated by analysis of 1D, 2D – NMR spectra and compared with published data AA02 was chemically identified β-sitosterol-3-O-β-D-glucopyranoside The structure of β-sitosterol-3-O-βD-glucopyranoside can be seen structure in Figure (a) (b) (c) Figure 6: (a) TLC of AA02; (b) AA02 powder (c)The structure of β-sitosterol-3-O-β-D-glucopyranoside 11 Testing -glucosidase inhibiton ability Firstly, the absorption of positive control and kinds of extracts were measured The Table and Figure showed the inhibition of acarbose propotion to concentrations IC50 was determined as can be seen in the Table and Figure Table 1: The inhibition of Acarbose Concentration 12 24 36 30.814 44.089 52.130 48 60 (μg/mL) Inhibition (%) 61.259 61.483 R2=0.9854 CONCENTRATION ( g/mL) Figure 7: The inhibition of Acarbose Table 2: IC50 of positive control (Acarbose) and kinds of extract Acarbose Concentration 31.60 SE (μg/mL) 1.041 Hexane Ethyl extract extract extract 1,099 2.004 11.38 1.074 1,085 1.715 12 Acetate Methanol Figure 8: Comparing IC50 of positive control and extracts Secondly, the various fractions of Ethyl Acetate extract were performed to test the inhibition -glucosidase activity The IC50 values of fractions were summarized in Table and Figure In which, these fractions already obtained by MPLC Table 3: The inhibition of fractions from Ethyl Acetate extract Concentration 10 40 80 120 160 (μg/mL) IC50 SE (μg/mL) Inhibition E2 23.24 87.74 93.98 97.97 52.36 1.029 (%) E4 2.05 37.44 70.93 79.19 94.98 1.047 E5 5.18 41.68 44.08 81.82 106.10 1.144 E7 24.51 33.19 34.05 35.79 696.20 1.639 E9 8.89 63.55 74.83 88.72 73.37 1.091 E10 22.87 72.66 83.09 98.92 22.10 1.324 E12 40.35 62.94 94.61 97.84 16.03 1.357 E17 37.56 55.56 68.89 91.11 23.08 E18 47.13 85.93 96.67 97.26 25.86 13 1.132 1.030 Figure 9: IC50 values of fractions of Ethyl Acetate extract (μg/mL) Antioxidant assay The antioxidant was tested by using DPPH assay Ascorbic acid seemed to be the positive control Extracts were tested firstly Then, fractions of Ethyl Acetate extract were tested The tested results were summarized in Table Figure 10 showed the IC50 value of Ethyl Acetate extract and its fraction and positive control, except E17 and E18 fraction Table 4: the inhibition of extracts and fractions of Ethyl Acetate extract of Artocarpus altilis (Parkinson) Fosberg leaves Concentration (μg/mL) 20 40 60 80 IC50 SE (μg/mL) Inhibition Ascorbic acid 51.93 83.04 85.41 87.12 15.77 1.100 Hexane 10.35 12.37 14.12 14.72 27,664 1.606 25.17 32.67 45.70 60.54 63.79 1.127 10.57 12.15 14.20 15.74 11,626 (%) extract Ethyl Acetate extract Methanol extract 14 1.935 E2 45.08 47.91 57.93 67.73 32.95 1.211 E4 40.45 68.87 68.65 69.52 25.39 1.270 E5 39.61 68.43 67.37 72.45 26.32 1.213 E7 36.16 66.26 67.12 69.51 29.29 1.203 E9 13.58 31.38 47.18 62.97 61.58 1.023 E10 14.32 28.24 41.58 59.24 68.43 1.061 E12 12.80 21.33 32.78 46.35 93.98 1.094 E17 11.34 12.49 13.26 15.02 215,970 6.176 E18 11.46 12.27 13.91 14.72 269,113 4.551 Figure 10: IC50 value of Ethyl Acetate extract and its fractions of Artocarpus altilis (Parkinson) Fosberg leaves in antioxidant test Phytochemical screening The presence of phytochemical compounds in the crude extract of Artocarpus altilis (Paskinson) Fosberg leaves and its Ethyl Acetate extract were summarized in Table 15 Table 5: The phytochemical screening of Artocarpus altilis (Paskinson) Fosberg leaves Type compounds of Result Observation Crude Ethyl Acetate extract extract Alkaloids + - Reddish precipitate Glycosides + + Brick red precipitate Saponins + - Foaming/frothing Tannins + - Greenish black precipitate Steroids + + Reddish brown ring color Flavonoids + + Orange–pink coloration (+): present (-): absent 16 IV DISSCUSION The Artocarpus altilis (Paskinson) Fosberg leaves were fractionated into 12 fractions of Hexane extract, fractions of Ethyl Acetate extract and fractions of Methanol extract by using different solvents with different polarity From the 8th fraction of Ethyl Acetate extract, β-sitosterol-3-O-β-D-glucopyranoside, was obtained That compound was white amorphous, with melting point is 269 – 270oC, crystallized in Methanol [13] β-sitosterol-3-O-β-D-glucopyranoside did not show any antidiabetics and DPPH scavenging effect[14] but showed selective activity with the antimicrobial spectra to 95 %[15] The fractions were used to test inhibit - glucosidase activity and DPPH assay Recently, Lee et al.[12] reported that natural products with wide structural diversity were a good source of -glucosidase inhibitors Thus, it is necessary to determine the -glucosidase inhibitory activity of Artocarpus altilis (Paskinson) Fosberg In this study, to determine the effects of the Artocarpus altilis (Paskinson) Fosberg leaves extracts on -glucosidase activity, we calculated the IC50 values, as shown in Table and Almost fractions of the Ethyl Acetate extracts seemed to have potent inhibitory activities towards -glucosidase The E12 was the strong inhibit fraction with the IC50 value of 16.03 1.357 μg/mL However, the - glucosidase inhibitory activities of the different extracts varied greatly The Hexane and Methanol extract had a higher IC50 value 1,099 2.004 and 1,085 1.715 μg/mL, respectively, as compared to the Ethyl Acetate extract with the lowest IC50 value (11.38 1.074 μg/mL) This may be due to the fact that Ethyl Acetate extract contained more effective -glucosidase inhibitory compounds, including glycosides, steroids and flavonoids Acarbose, known to be an effective microbial -glucosidase inhibitor (IC50 =31.6 1.041 μg/mL), is used for diabetes therapy The Ethyl Acetate extract and fractions had lower IC50 value than Acarbose So, this herb may be a promising drug for antidiabeties therapy DPPH, a stable free radical is purple in color, but changes into a stable yellow compound upon reaction with an antioxidant It is common to measure the concentration of antioxidant required to reduce or inhibit 50% of the DPPH radicals present The inhibition abilities of various extracts against DPPH radical are illustrated in Table 4, and the results are expressed as IC50 values (μg/mL) for comparison purposes In experiments, all of the extracts tested possessed DPPH 17 radical scavenging activity The Ethyl Acetate extract was the most active DPPH inhibition with IC50 value of 63.79 1.127 μg/mL whereas the lowest activity was found in Hexane and Methanol extract with IC50 value in turn 27,664 1.606 and 11626 1.935 μg/mL Overall, the DPPH inhibition activities of all the extracts were lower to that of the positive control, Ascorbic acid (IC50 value is 15.77 1.10μg/mL) Extracts obtained with different solvents varied in their DPPH inhibition activities, indicating that the extraction medium significantly affected the strength of antioxidants in the extracts In general, the most active DPPH inhibition was fractions of Ethyl Acetate extract with IC50 value varies from 25.39 93.98 1.270 to 1.094 μg/mL, possibly due to a higher content of glycosides, steroids and flavonoids compounds E17 and E18 fractions did not inhibit This observation is consistent with a report that flavonoid compounds contribute directly to the antioxidative action [11] A number of different classes of compounds with antidiabeties and antioxidant activity have been isolated from plants including tannins, glycosides, saponins, steroids, flavonoids and alkaloid Therefore, the phytochemical analysis of leaf extracts was carried out to locate the possible classes of compounds responsible for antidiabeties and antioxidant activity Among these phytoconstituents, glycosides, steroids and flavonoids of Ethyl Acetate extract showed significant correlation with antidiabeties and antioxidant activity V CONCLUSION: In this study, the antioxidative, -glucosidase inhibitory activities of Artocarpus altilis (Paskinson) Fosberg leaves extracts were investigated β-sitosterol-3-O-β-Dglucopyranoside was collected from Ethyl Acetate extract The -glucosidase inhibitory potential of Artocarpus altilis (Paskinson) Fosberg leaf extracts shore up its utilisation in the folk medicine for the better treatment of antidiabeties The result of DPPH assay indicated Artocarpus altilis (Paskinson) Fosberg leaf extracts had lower ability to inhibit DPPH activity The correlation between the phytochemical analysis and -glucosidase and DPPH inhibitory activity in this investigation suggests that the high content of glycosides, steroids and flavonoids compounds in the leaf extracts could be involved in exerting the -glucosidase and DPPH inhibitory activity Further studies on isolation and characterization from Ethyl Acetate extract of Artocarpus altilis leaf would be highly recommended 18 REFERENCES [1] Diane Ragone, Promoting the conservation and use of underutilized and neglected crops: Breadfruit, Artocarpus Altilis (Paskinson) Fosberg, vol 10, 1997; p14 [2] Kasahara S, Hemmi S Medicinal Herb Index In Indonesia Bogor, Indonesia, PT Eisai Indonesia, 1988, page 1-2 [3] Shimizu K, Kondo R, Sakai K, Buabarn S, Dilokkunanant U; α-Reductase inhibitory component from leaves of Artocarpus Altilis , 2000; page 385-389 [4] Wang Y, Xu K, Lin L, Pan Y, Zheng X; Geranyl flavonoids from the leaves of Artocarpus altilis, Phytochem, 2007; page 1300-1306 [5] Wang Y., Deng, T., Lin, L., Pan, Y., Zheng, X., Bioassay guided isolation of antiatherosclerotic phytochemicals from Artocarpus altilis, Phytotherapy Research 20, 2006, 1052–1055 [6] Phạm Ngọc Ẩn, Phạm Thị Nhật Trinh, Mai Đình Trị, Lê Tiến Dũng, Nghiên cứu thành phần hoá học sa kê Artocarpus altilis (Park) Fosberg, Chemistry magazine vol49, 2011, page 87-91 [7] Lotulung PD, Fajriah S, Hanafi M, Filaila E, Identification of cytotoxic compound from Artocarpus communis leaves against P-388 cells, Pak J Biol Sci;11(21), 2008, page 2517-2520 [8] Blois MS, Antioxidant determinations by the use of a stable free radical J pn J Nature, 1958, 181: 1199-1200 [9] Ph Pro Nguyễn Kim Phi Phụng, Các phương pháp tách chiết hợp chất hữu cơ, Nhà xuất Đại học Quốc gia TP Hồ Chí Minh, 2007, page 155, 74 [10] Jinfeng Yang, Ju-Sung Kim, Yeo Jin Sa, Myeong Ok Kim, Hyun Ju Jeong; Antioxidant, antibacterial and α-glucosidase inhibitory activities of different extracts of Cortex Moutan, African Journal of Biotechnology Vol 10, 2011, page 9438-9444 [11] Shen Y, Jin L, Xiao P, Lu Y, Bao J; Total phenolics, flavonoids, antioxidant capacity in rice grain and their relations to grain color, size and weight J Cereal Sci, 2009, 49: 106-111 [12] Lee B, Shin YW, Bae EA, Han SJ, Kim JS, Kang SS, Kim DH, Antiallergic effect of the root of Paeonia lactiflora and its constituents paeoniflorin and paeonol Arch Pharmacol, 2008, Res 31: 445-450 19 [13] Tôn Nữ Liên Hương, Nguyễn Minh Hiền and Trần Đình Luận, Study on the chemical composition of Achyranthes aspera L growing in Tra Vinh Province, Sciences magazine, 2011, 19b 56-61 [14] Han J, Weng X, Bi K, Antioxidants and antidiabetic from Chinese medicinal herb-Lithospermum erythrorhizon, Food Chemistry, 2008, 106:2-10 [15] Kuete, V.; Eyong, K O.; Folefoc, G N.; Beng, V P.; Hussain, H.; Krohn, K.; Nkengfack, A E.; Antimicrobial activity of the methanolic extract and of the chemical constituents isolated from Newbouldia laevis, Die Pharmazie An International Journal of Pharmaceutical Sciences, Volume 62, 2007 , pp 552-556 20 [...]... fractions of Artocarpus altilis (Parkinson) Fosberg leaves in antioxidant test 4 Phytochemical screening The presence of phytochemical compounds in the crude extract of Artocarpus altilis (Paskinson) Fosberg leaves and its Ethyl Acetate extract were summarized in Table 5 15 Table 5: The phytochemical screening of Artocarpus altilis (Paskinson) Fosberg leaves Type compounds of Result Observation Crude... of extracts were measured The Table 1 and Figure 7 showed the inhibition of acarbose propotion to concentrations IC50 was determined as can be seen in the Table 2 and Figure 8 Table 1: The inhibition of Acarbose Concentration 12 24 36 30.814 44.089 52.130 48 60 (μg/mL) Inhibition (%) 61.259 61.483 R2=0.9854 CONCENTRATION ( g/mL) Figure 7: The inhibition of Acarbose Table 2: IC50 of positive control (Acarbose)... drug for antidiabeties therapy DPPH, a stable free radical is purple in color, but changes into a stable yellow compound upon reaction with an antioxidant It is common to measure the concentration of antioxidant required to reduce or inhibit 50% of the DPPH radicals present The inhibition abilities of various extracts against DPPH radical are illustrated in Table 4, and the results are expressed as IC50... locate the possible classes of compounds responsible for antidiabeties and antioxidant activity Among these phytoconstituents, glycosides, steroids and flavonoids of Ethyl Acetate extract showed significant correlation with antidiabeties and antioxidant activity V CONCLUSION: In this study, the antioxidative, -glucosidase inhibitory activities of Artocarpus altilis (Paskinson) Fosberg leaves extracts... of Ethyl Acetate extract were tested The tested results were summarized in Table 4 Figure 10 showed the IC50 value of Ethyl Acetate extract and its fraction and positive control, except E17 and E18 fraction Table 4: the inhibition of extracts and fractions of Ethyl Acetate extract of Artocarpus altilis (Parkinson) Fosberg leaves Concentration (μg/mL) 20 40 60 80 IC50 SE (μg/mL) Inhibition Ascorbic acid... showed selective activity with the antimicrobial spectra to 95 %[15] The fractions were used to test inhibit - glucosidase activity and DPPH assay Recently, Lee et al.[12] reported that natural products with wide structural diversity were a good source of -glucosidase inhibitors Thus, it is necessary to determine the -glucosidase inhibitory activity of Artocarpus altilis (Paskinson) Fosberg In this... investigated β-sitosterol-3-O-β-Dglucopyranoside was collected from Ethyl Acetate extract The -glucosidase inhibitory potential of Artocarpus altilis (Paskinson) Fosberg leaf extracts shore up its utilisation in the folk medicine for the better treatment of antidiabeties The result of DPPH assay indicated Artocarpus altilis (Paskinson) Fosberg leaf extracts had lower ability to inhibit DPPH activity... analysis and -glucosidase and DPPH inhibitory activity in this investigation suggests that the high content of glycosides, steroids and flavonoids compounds in the leaf extracts could be involved in exerting the -glucosidase and DPPH inhibitory activity Further studies on isolation and characterization from Ethyl Acetate extract of Artocarpus altilis leaf would be highly recommended 18 REFERENCES [1] Diane... (11.38 1.074 μg/mL) This may be due to the fact that Ethyl Acetate extract contained more effective -glucosidase inhibitory compounds, including glycosides, steroids and flavonoids Acarbose, known to be an effective microbial -glucosidase inhibitor (IC50 =31.6 1.041 μg/mL), is used for diabetes therapy The Ethyl Acetate extract and fractions had lower IC50 value than Acarbose So, this herb may be a... Secondly, the various fractions of Ethyl Acetate extract were performed to test the inhibition -glucosidase activity The IC50 values of fractions were summarized in Table 3 and Figure 9 In which, these fractions already obtained by MPLC Table 3: The inhibition of fractions from Ethyl Acetate extract Concentration 10 40 80 120 160 (μg/mL) IC50 SE (μg/mL) Inhibition E2 23.24 87.74 93.98 97.97 52.36 1.029 ... Corresponding author’s email address: ly .le@ hcmiu.edu.vn ACKNOWLEDGEMENT I would like to express my deepest gratitude to my supervisor, Dr Le Thi Ly, for her wide knowledge on Applied Chemistry Her understanding,... called Sake The plant Artocarpus altilis (Parkinson) Fosberg is belonging to the family Moraceae, 10-15m tall, evergreen Bark grayish brown, thick as showed in Figure Branchlets are 0.5-1.5cm thick... extracts[9] The leaves of Artocarpus altilis (Parkinson) Fosberg were collected from Ho Chi Minh City The leaves were washed thoroughly under tap water, shade dried, powdered The powdered leaves were