Phytochemical analysis of
Antibiotic resistance of Pseudomonas aeruginosa causes many infectious diseases and it is agreat. So, the aim of the present work was to assess the antibacterial, antibiofilm activity of Beta vulgaris extracts against resistance bacteria P. aeruginosa that were clinically isolated and tested for their antiprotease potential. Result showed that methanol extract exhibited important antiprotease activity against Trypsin, Savinase, and digestive proteases of blue crab with percentage of inhibition of 94.66, 91.39, and 86.41%, respectively. It showed also important antibiofilm activities against multidrug-resistant P. aeruginosa with inhibition values upper than 80% with a concentration of 4MIC. Our investigation delivered that Beta vulgaris might be possible source of natural antienzymatic, antimicrobial, and antibiofilm agents.
- Beta vulgaris
- multidrug-resistant P. aeruginosa
Many studies have demonstrated that vegetables play a significant role in human nutrition. They reduced risk of many chronic diseases, like diabetes, cardiovascular illnesses, and cancers [1, 2, 3] and Alzheimer’s diseases [4, 5]. These advantageous properties of vegetables are due to the bioactive compositions known for their important antioxidant activities [6, 7].
The objective of this chapter was to investigate the antiprotease, antimicrobial, and antibiofilm activities of
2. Materials and methods
2.1 Plant material
The fresh beetroots were bought from a market in Sousse (Tunisia) and the roots were identified and a voucher specimen was placed in our laboratory at the Faculty of Pharmacy (Monastir).
2.2 Preparation of aqueous extract of
About 200 ml of distilled water was added to 50 g of
2.3 Preparation of methanolic extract of
Beetroots were washed and sliced into small pieces and then 200 ml of methanol was added to 100-g root in brawn bottle for 3 days at room temperature, filtered through Whatman filter paper, and dried with rotavapor. Then the extract was kept at 4°C.
2.4 Total polyphenol content
The total phenolic content was tested by Folin-Ciocalteu method (Edziri et al.) . The total polyphenols content is expressed as mg gallic acid equivalents (GAEs) per g of extract.
2.5 Total flavonoid content
The flavonoids content was tested by the method of Othmana et al. . The result is expressed in mg quercetin equivalents (QEs) per g of extract.
2.6 Total tannin contents
Total tannin content in
2.7 Total carotenoid content
Total carotenoids content of
2.8 Antiprotease activity
The impact of
2.9 Antibacterial activity of
2.9.1 Microdilution assay
Minimum inhibitory concentration (MIC) values were determined by a microdilution method as indicated by Edziri et al. . The MIC was defined as the lowest concentration that inhibits the development of bacteria, after 24 h of incubation .
2.9.2 Antimicrobial activity
126.96.36.199 Micro-well determination of MIC and MBC
The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for all bacteria tested in this work by a microdilution method as described by . The MIC was distinct as the lowest concentration of the extract to inhibit the development of the bacteria.
2.9.3 Inhibition of biofilm formation
The biofilm inhibition was tested against five multidrug-resistant strains of
3. Results and discussion
3.1 Phytochemical screening
The proportions of the phenols, flavonoids, tannins, and carotenoids contents are summarized in Table 1. Methanolic extract of
|Total polyphenols (mg GAE/ g) extract||99.47 ± 0.45||134.55 ± 0.6|
|Total flavonoids (mg EQ/g) extract||1.29 ± 0.50||4.34 ± 0.02|
|Total tanin content(mg TA/g)||6.15 ± 1.4||7.5 ± 0.5|
|Carotenoids (mg/100 g FW)||2.1 ± 1.2||2.97 ± 0.4|
3.2 Antiprotease, antibacterial and antibiofilm activities
The antiprotease activity of various
|Purafect||89.31 ± 1.13||60.70 ± 0.96|
|Savinase||91.39 ± 1.38||81.07 ± 0.43|
|Chymotrypsin||65.28 ± 0.47||51.53 ± 0.51|
|Trypsin||94.66 ± 0.32||87.42 ± 1.55|
|Digestive proteases of blue crab||86,41 ± 0.34||70.11 ± 0.61|
It is interesting to note that the proteolytic activities of Savinase® and Purafect®, commercial microbial proteases, were mostly inhibited by methanol extract by about 91.39 and 89.31%, respectively. In addition, it was efficient to reduce 94.66% of digestive trypsin activity. In addition aqueous extracts exhibit good antiprotease activity.
According to Table 3, the values of MIC for two extracts against multidrug-resistant
The two extracts showed important antibiofilm activity (Figures 1 and 2). Furthermore, methanolic extract exhibited the greatest antibiofilm property against all resistant strains of PA with inhibition values greater than 80% at the concentration of 4MIC. In addition, aqueous extract inhibited the biofilm formation of PA greater than 50% with 2MIC. We can observe that there is not any difference between the tested strains of PA. Also methanol extract of
From this study, we can see that
Furthermore, this vegetable can be used as a source of natural antienzymatic, antimicrobial, and antibiofilm agents. Research is in progress to identify and isolate the bioactive molecules and to test them in vivo.