Use of grapefruit seed extract in parasite management: first results of in vitro examinations

Increased resistancies of parasites are a challenge in parasite management worldwide. During the last decade a lot of research about secondary plant ingredients were conducted [1],[2],[3]. But farmers are still missing solutions in alternative parasite management. The aim of this study was to investigate the influence of grapefruit seed extract (GSE) on the exsheathment rate of parasitic third larvae in vitro. GSE was sourced from the local pharmacy. The content of bioflavonoids (naringin, hesperidin, néohepéridine, narirutine) was according to the certificate at 8 mg/ml. The parasitic larvae were extracted from faeces of pastured goats of the station after incubation of the feces at 28 °C for 10 days. The purified larvae were incubated with two differently concentrated GSE dilutions(GSE1: 1,6 mg/ml; GSE2: 3,2 mg/ml), with tetramishole hydrochloride (positiv control) and water (negativ control) for 3 hours at 22 °C. The proportion of exsheathment was counted 20, 40 and 60 minutes after starting the exsheathment process with diluted sodium hypochlorite solution. After 60 minutes the exsheathment rates of the negative control, positive control, GSE1 and GSE2 were 96,7 %, 4,2 %, 6,4 % and 15,1 %, respectively. The exsheathment rate of the positive control reflects the situation of resistancy in parasites of goats of the station. Although the in vitro examination in GSE showed comparable results with the positive control further investigations are necessary to verify these effects under agricultural field conditions.

• References

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