α glu

Sa was previously isolated from Usnea subfloridana Stirton^{18 (link)} and Usnea laevis Nyl.^{19 (link)} in good yields and reported by our group. STZ was obtained from Himedia Laboratories Pvt. Ltd. (Mumbai, India) and amylase HR reagent was obtained from Pro Lab Marketing Pvt. Ltd. (New Delhi, India). Recombinant human (rH) AR, rH DPP-IV, LIP from porcine pancreas, α-Amy from porcine pancreas, α-Glu from Saccharomyces cerevisiae, 2,2-diphenyl-1-picrylhydrazyl (DPPH·), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS⁺·) and intestinal acetone powders from rats were purchased from Sigma Aldrich (Mumbai, India). Sildenafil citrate and rat feed were procured from Sun Pharma Ltd. (Mumbai, India) and Hindustan Lever Ltd. (Mumbai, India), respectively. All other chemicals used in the present study were at analytical grade.

The inhibitory capacity of α-glu activity was determined using the method described by Li et al. (2016) , using p-nitrophenyl α-D-glucopyranoside (p-NPG) as a substrate. The reaction mixture containing sterile phosphate-buffered saline (PBS) pH 6.5 (200 μl), p-NPG 20mM (8 μl), bacterial suspension (10 μl) and α-glu (0.17 U ml⁻¹ (Sigma-Aldrich, MO, USA.) was incubated at 37 °C for 20 min. The amount of p-nitrophenol released was quantified by measuring OD_405.