Table 5 Binding affinity values and interacting residues of isolated compounds from N. thomsonianum toward α-glucosidase, α-amylase and PTP1B

Nt01

−6.68

Phe157, His239, Asn241

−5.26

Trp59, Gln63, Leu165

−4.93

Arg24, Arg254, Met258

Nt02

−4.09

Phe157, His239, Arg312

−4.52

Tyr62

−3.84

Arg24, Arg254,

Nt03

−7.16

Arg312, Asp408

−5.94

Tyr62, His201, His299

−5.19

Arg254, Gly259

Acarbose

−9.27

Asp214, His279, Glu304, Pro309, Arg312, Asp349, Arg439

−9.57

Trp59, Gln63, Arg195, Asp197, Lys200, His201, Glu233, Glu240, Asp300, Gly306

–

–

Ursolic acid

–

–

–

–

−5.72

Arg24, Arg254, Gly259