Novel Bioactive Natural Products Isolated from Madagascar Plants and Marine Organisms (2009-2017)

Bioactive Compounds and In Vitro Antioxidant and Anticoccidial Activities of Opuntia ficus-indica Flower Extracts

The objective of the present study is to identify the biochemical compounds extracted from OFI flowers using ultra-high-performance liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry and to evaluate their in vitro antioxidant activities and anticoccidial effects on the destruction of Eimeria oocysts isolated from naturally infected chickens. A domestic microwave was used with a refrigerant to condense the vapors generated during the extraction. The flavonoid and phenolic compound contents of the OFI flowers were determined according to standard methods. DPPH radical and H2O2 scavenging capacities were used to assess the antioxidant activity. Regarding the anticoccidial activity, the Eimeria spp. oocysts used were isolated from the fresh feces of infected broilers and were determined in triplicate by incubation at an ambient temperature for 24 h. The results highlighted the considerable influence of the optimized acetone concentration, ratio, irradiation time, and microwave power parameters on the phenolic content and antioxidant activities. Our results revealed significant matches between the predicted and experimental values of the models. Molecular analysis revealed the presence of several biophenol classes such as quercetin, isorhamnetin 3-O-rutinoside, and quercetin-3-O-rutinoside. OFI flower extracts inhibited sporulation and damaged the morphology of Eimeria oocysts compared with normal sporulated Eimeria oocysts containing sporocysts. In conclusion, the optimized conditions were validated and found to fit very well with the experimental values. These findings suggest that the flowers of OFI should be considered sources of antioxidants. The results of the present study revealed that OFI flower extracts have anticoccidial activities against Eimeria-spp.-induced infection in broiler chickens.

In Vitro Anticoccidial Activity of Olive Pulp (Olea europaea L. var. Chemlal) Extract Against Eimeria Oocysts in Broiler Chickens

AIM

The objective of the present study was to investigate in vitro anticoccidial effect of olive pulp (Olea europaea L var. Chemlal) extract on the destruction of Eimeria spp. oocysts isolated from infected chickens naturally.

MATERIALS AND METHODS

The olive pulp (OP) powder was stirred manually in aqueous ethanol in preparation for extraction using the microwave-assisted extraction system. The identification of the phenolic compounds was obtained by ultra-high-performance liquid chromatography-mass spectrometry with electrospray ionisation (HPLC-ESI-MS). The treatment of Eimeria oocyst with OP extract and standard compounds (quercetin and oleuropein) leads to their lysis as shown by the release of substances absorbing at 273 nm.

RESULTS

Our results showed that the maximum number of reduced oocysts was recorded after 8 h of incubation of optimum OP extract, quercetin and oleuropein for different periods of time. Also, the number of Eimeria oocysts decreased considerably with increase concentrations after adding the optimum of OP extract in concentration ranging from 0.023 to 0.371 mg/ml. Positive correlation between the optimum OP extract concentrations and the number of Eimeria oocysts reduced was R² = 0.959. From this in vitro experiment, it can be concluded that the OP extract possesses an anti-Eimeria spp activity.

CONCLUSION

To our knowledge, this is the first time that quercetin and oleuropein were tested to evaluate their anticoccidial activity. The findings of this study showed that phenolic compound of OP extract tested separately possesses anti-Eimeria spp. effect. Further studies should be carried out to test its in vivo efficacy of the OP bioactive compounds in broiler chickens.

Synthesis and biological activity of new derivatives with the preserved carane system

Terpenoid derivatives, which contain a preserved carane system in their structure, exhibit a broad spectrum of biological activities. Among them, we can distinguish insecticides, structures with pharmacological application etc. In the presented paper, the substrate - (-)-cis-caran-trans-4-ol was transformed using the reactions of typical organic synthesis to obtain novel derivatives. Most importantly, bromolactone ((-)-(1R,4R,6S)-2'-(bromomethyl)-4,7,7-trimethylspiro[bicyclo[4.1.0]heptan-3,3'-furan]-5'(4'H)-one) with the preserved carane system was synthesized. This bromolactone was tested for antifeedant activity against the lesser mealworm, Alphitobius diaperinus Panzer, and peach potato aphid (Myzus persicae). In addition, its moderate antibacterial activity was observed against the Bacillus subtilis strain (with Minimal Inhibitory Concentration of 200 µg/mL).