Antibacterial activity of black and green tea extracts against multidrug resistance Shigella sonnei and Shigella flexneri an integrated experimental study and computational approach

Shigella spp. is well known for shigellosis in humans. Growing
resistance pattern of Shigella spp. to different antibiotics is increasing
global public health concerns. This study has been conducted to
evaluate the antibiotics sensitivity of Shigella sonnei and Shigella
flexneri, the antibacterial activity of methanol extract of black tea (BT)
and green tea (GT), and the docking study was performed using 28
phytochemicals from Camellia sinensis with Shigella effector protein
kinase OspG (4BVU) as well as in silico drug-likeness and ADME
properties were also studied. Both S. sonnei and S. flexneri exhibited
diverse antibiotics resistance patterns. Interestingly, methanol extract
of GT showed higher antibacterial activity than BT extract against both
bacteria. In addition, the docking study exposed 50% phytocompounds from Camellia
sinensis which have strong inhibitory activity against 4BVU compared to control
ciprofloxacin with binding energy of more than -7.40 kcal/mol. The highest binding affinity -
9.70 kcal/mol was found by theaflavin with 21 interacting amino acid residues from 4BVU.
However, drug-likeness and ADME properties showed Lipinski’s violation of our top binding
ligand theaflavin, whereas 2nd and 3rd highest binding compounds theaflavic acid and
theaflagallin showed violation with one parameter in H-bond donor. Therefore, present
observation suggests Camellia sinensis may have the inhibitory activity against S. sonnei and S. flexneri, and phytocompunds theaflavic acid and theaflagallin could be used as effective drug candidates against Shigella spp.