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Entada spiralis Ridl. or also known as 'akar beluru' or 'akar sintok', is one of the least studied species in the Fabaceae family. The species was famous for its soap-like properties in which the natives use them as soap and shampoo for hygiene and treating itchiness. The phytochemicals and biochemicals properties of this plant have always been an interesting area to be discovered, as the study of the species is still scanty. In this study, the aim is to evaluate the antibacterial effects of the E. spiralis leaves extracts against two Gram-negative phytobacteria species, Erwinia chrysanthemi (ATCC 437624) and Erwinia carotovora (ATCC 15713) for the discovery of the natural active bactericides. Hexane, dichloromethane, ethyl acetate and methanol were used as menstruum in producing the extracts through cold maceration method. The extracts were subjected to screening tests for identification of phytochemicals which revealed the presence of phenolics, terpenoids, saponins, coumarins, flavonoids, and tannins. Antibacterial activities of the extracts were assessed via Kirby-Bauer disk diffusion method by measuring the inhibition zones post-incubation for 24 hours at room temperature. While, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated through broth microdilution method after incubation at room temperature for 24 hours. Output data from this study showed that, methanol extract against E. chrysanthemi and ethyl acetate extract against E. carotovora have the maximum zone of inhibition in antibacterial susceptibility with 22.7 ± 0.6 mm and 26.3 ± 0.6 mm respectively at 400 mg/mL concentration. In accordance with MIC, E. chrysanthemi was revealed to be most susceptible in methanol extract with MIC value of 1.56 ± 0.00 mg/mL (MBC value at 3.13 ± 0.00 mg/mL). E. carotovora has been determined to be best susceptible also in ethyl acetate extracts with MIC values of 0.65 ± 0.23 mg/mL (MBC value at 2.60 ± 0.90 mg/mL). [ABSTRACT FROM AUTHOR]

The Pectobacterium bacteria are classified among the most economically important pathogens for growing potatoes. In recent years, an increase in diseases caused by these bacteria could be observed. The purpose of this work is the study of the antibacterial activity in vitro of five plant extracts namely grains of black cumin (Nigella sativa L.), cloves (Syzygium aromaticum), Eucalyptus camaldulensis, wild carrot (Daucus carota L.) and thyme Numidia (Thymus numidicus), against the strain Pectobacterium collected in a production parcel located in the region of Ain Defla. The strain isolated, purified and identified is called Pectobacterium carotovorum subsp. carotovorum (P.c.c). The study in vitro of antibacterial activity of Nigella sativa L. seeds and essential oil Daucus carota shows inhibition zone diameter (ID) less than 8 mm, attesting the non-sensitivity of strain against these two extracts. However, the strain studied is extremely sensitive to the extract of Thymus numidicus with an inhibition zone diameter (ID) of 20 mm. It is very sensitive to the extract of Eucalyptus camaldulensis with an inhibition zone diameter (ID) of 17 mm. Thus, it is also sensitive to the clove that is to say about 14 mm diameter of inhibition zone (ID). The minimum inhibitory concentrations (MIC), recorded for the cloves are (D4) 1/8 and (D5) 1/16 for Eucalyptus camaldulensis and Thymus numidicus. The study of the bactericidal or bacteriostatic effect confirms the bactericidal effect of the essential oil of Thymus numidicus against the bacterial strain studied through the absence of bacterial colonies for concentration 1. While for the extract of Eucalyptus camaldulensis and clove we see the resumption of bacterial growth for all concentrations used. This confirms the bacteriostatic effect. [ABSTRACT FROM AUTHOR]