Effects of Kimchi Extract and Temperature on Embryostasis of Ascaris suum Eggs

Abstract

To determine the effects of kimchi extracts at different temperatures on larval development, Ascaris suum eggs were mixed with soluble part of 7 different brands of commercially available kimchi and preserved at either 5℃ or 25℃ for up to 60 days. A. suum eggs incubated at 25℃ showed marked differences in larval development between kimchi extract and control group. While all eggs in the control group completed embryonation by day 21, only 30% of the eggs in the kimchi extract group became embryonated by day 36 and about 25% never became larvated even at day 60. At 5℃, however, none of the eggs showed larval development regardless of the incubation period or type of mixture group. To determine the survival rate of A. suum eggs that showed no embryonation after being preserved at 5℃, eggs preserved in kimchi extracts for 14, 28, and 60 at 5℃ were re-incubated at 25℃ for 3 weeks in distilled water. While all eggs in the control group became larvated, eggs in the kimchi extract group showed differences in their embryonation rates by the incubation period; 87.4 % and 41.7% of the eggs became embryonated after being refrigerated for 14 days and 28 days, respectively. When refrigerated for 60 days, however, no eggs mixed in kimchi extract showed larval development. Our results indicate that embryogenesis of A. suum eggs in kimchi extract was affected by duration of refrigeration, and that all eggs stopped larval development completely in kimchi kept at 5℃ for up to 60 days.

Sensitivity and Specificity of Multiple Kato-Katz Thick Smears and a Circulating Cathodic Antigen Test for Schistosoma mansoni Diagnosis Pre- and Post-repeated-Praziquantel Treatment

“…Drug-induced embryostasis, has been demonstrated in Onchocerca volvulus [52] and Ascaris suum [53]. Embryostasis could explain our lower sensitivities (73%) at four-weeks-post-praziquantel than those observed in a stable, low transmission Western Kenyan region (prevalence 38.8%, sensitivity = 96%) [34].…”

“…In contrast, at four-weeks-post-praziquantel, positive POC-CCA results in egg negative individuals may have occurred due to juveniles unaffected by treatment, newly acquired infections, and/or worms which survived treatment, but with reduced or cessated egg production (embryostasis). Drug-induced embryostasis, has been demonstrated in Onchocerca volvulus [52] and Ascaris suum [53] . Embryostasis could explain our lower sensitivities (73%) at four-weeks-post-praziquantel than those observed in a stable, low transmission Western Kenyan region (prevalence 38.8%, sensitivity = 96%) [34] .…”

2-Methyl-pentanoyl-carnitine (2-MPC): a urine biomarker for patent Ascaris lumbricoides infection

“…Also, some individuals from endemic areas that were negative by qPCR might still carry a low worm burden with only adult male or pre-adult worms in their gut as these will not result in shedding of eggs and DNA in stool; or were simply not detected by qPCR, something that has been observed before 8,19 . For the samples collected post-treatment, the remaining 2-MPC levels in otherwise Kato-Katz negative individuals may be attributed to worms which survived treatment, but with reduced or cessated egg production (drug-induced embryostatis), a phenomenon already demonstrated for Onchocerca volvulus and A. suum 20,21 . Alternatively, the analytical method used to determine 2-MPC might be affected by some interferences (possibly the closely eluting 3-MPC, but also other unknown molecules might be interfering), present in varying small quantities, but with the same mass fragment ions as 2-MPC and co-eluting at similar retention time.…”

Detection of Ascaris lumbricoides infection by ABA-1 coproantigen ELISA

“…The very low ABA-1 levels observed after 24 days in some subjects may be attributed to worms which survived treatment, but with reduced or cessated egg production (drug-induced embryostasis), a phenomenon already demonstrated for Onchocerca volvulus and A . suum [ 38 , 39 ]. Alternatively, this could also be caused by some remaining ABA-1 in the gut or possibly even from a new worm infection.…”