TY - JOUR
T1 - Crystal structure and in vitro antimicrobial activity studies of Robustic acid and other Alpinumisoflavones isolated from Millettia thonningii
AU - Harrison, Jerry Joe E.K.
AU - Ayine-Tora, Moscoh Daniel
AU - Appiagyei, Benjamin
AU - Mills-Robertson, Felix C.
AU - Asomaning, William A.
AU - Achel, Daniel G.
AU - Ishida, Hiroyuki
AU - Kingsford-Adaboh, Robert
N1 - Publisher Copyright:
© 2019 Walter de Gruyter GmbH.
PY - 2019/4/1
Y1 - 2019/4/1
N2 - We report a systematic study of the antibacterial inhibitory potential of isoflavone natural products isolated from the seeds extracts of Millettia thonningii. In an effort to gain bond topological information which may have consequences for the observed bioactivities, the crystal structure of robustic acid was solved and refined using the independent atom as well as the invariom model, and the structures were compared. Robustic acid contains a fused tricyclic unit with a benzopyran moiety, with a phenylene ring substitution on the coumarin ring similar to the alpinumisoflavones isolated from this plant. At a minimum inhibitory concentration of ~1 mg/mL, alpinumisoflavone and robustic acid were found to be cytotoxic to Staphylococcus aureus (ATCC 25923) showing a zone of inhibition (ZOI) of ~9 mm. On the other hand, at ~2 mg/mL, these compounds were found to be bacteriostatic to a hospital isolate of Salmonella typhi with about 7 mm ZOI. Taken together, these compounds offer potential new avenues for targeting both Gram positive and negative bacteria and could be useful as chemical probes for understanding these pathogens in an effort to overcome drug resistance.
AB - We report a systematic study of the antibacterial inhibitory potential of isoflavone natural products isolated from the seeds extracts of Millettia thonningii. In an effort to gain bond topological information which may have consequences for the observed bioactivities, the crystal structure of robustic acid was solved and refined using the independent atom as well as the invariom model, and the structures were compared. Robustic acid contains a fused tricyclic unit with a benzopyran moiety, with a phenylene ring substitution on the coumarin ring similar to the alpinumisoflavones isolated from this plant. At a minimum inhibitory concentration of ~1 mg/mL, alpinumisoflavone and robustic acid were found to be cytotoxic to Staphylococcus aureus (ATCC 25923) showing a zone of inhibition (ZOI) of ~9 mm. On the other hand, at ~2 mg/mL, these compounds were found to be bacteriostatic to a hospital isolate of Salmonella typhi with about 7 mm ZOI. Taken together, these compounds offer potential new avenues for targeting both Gram positive and negative bacteria and could be useful as chemical probes for understanding these pathogens in an effort to overcome drug resistance.
KW - Salmonella typhi
KW - Staphylococcus aureus
KW - antibacterial
KW - isoflavone
KW - robustic acid
UR - http://www.scopus.com/inward/record.url?scp=85064110226&partnerID=8YFLogxK
U2 - 10.1515/zkri-2018-2052
DO - 10.1515/zkri-2018-2052
M3 - Article
AN - SCOPUS:85064110226
SN - 2194-4946
VL - 234
SP - 229
EP - 235
JO - Zeitschrift fur Kristallographie - Crystalline Materials
JF - Zeitschrift fur Kristallographie - Crystalline Materials
IS - 4
ER -