Application of Sustainable Natural Resources in Agriculture: Acaricidal and Enzyme Inhibitory Activities of Naphthoquinones and Their Analogs against Psoroptes cuniculi

Abstract

As important secondary plant metabolites, naphthoquinones exhibit a wide range of biological activities. However, their potential as sustainable alternatives to synthetic acaricides has not been studied. This study for the first time investigates the acaricidal activity of naphthoquinones against Psoroptes cuniculi in vitro. Furthermore, the in vivo activity, the skin irritation effects, the cytotoxicity and the inhibitory activities against mite acetylcholinesterase (AChE) and glutathione S-transferase (GST) of the two compounds that displayed the best insecticidal activity in vitro were evaluated. Among fourteen naphthoquinones and their analogs, juglone and plumbagin were observed to possess the strongest acaricidal activities against P. cuniculi with LC50 values of 20.53 ppm and 17.96 ppm, respectively, at 24 h. After three treatments, these two chemicals completely cured naturally infested rabbits in vivo within 15 days, and no skin irritation was found in any of the treated rabbits. Compared to plumbagin, juglone presented no or weak cytotoxicity against HL-7702 cells. Moreover, these two chemicals significantly inhibited AChE and GST activity. These results indicate that juglone has promising toxicity against P. cuniculi, is safe for both humans and animals at certain doses, and could be used as a potential alternative bio-acaricide for controlling the development of psoroptic mange in agricultural applications.

Anthelmintic Activity of Extracts and Active Compounds From Diospyros anisandra on Ancylostoma caninum, Haemonchus placei and Cyathostomins

“…In particular, the presence of naphthoquinones, a group of highly reactive phenolic compounds, can be highlighted. These are important for the development of new agrochemical pharmaceuticals because of their broad antiparasitic effect, which has recently generated increasing research interest ( 61 ). Also, the antimicrobial, antifungal, anti-inflammatory, anticarcinogenic, antiprotozoal and acaricidal activities of Diospyros have been attributed to the presence of the 1,4-naphthoquinones, specifically plumbagin ( 13 , 32 , 62 – 64 ).…”

Nematicidal Activities of Three Naphthoquinones against the Pine Wood Nematode, Bursaphelenchus xylophilus

“…NTQs have been reported for their insecticidal and nematicidal activity [11,12,17,20,21]. Among the NTQ analogs, juglone and plumbagin showed the strongest acaricidal activities against P. cuniculi [14]. Plumbagin obtained from persimmon root, Diospyros kaki, had the most potent larvicidal activity against Aedes aegypti , and Ochlerotatus togoi [22].…”

“…Naphthoquinone is a class of organic compounds structurally related to naphthalene and is easily found in nature as products of microorganisms and as secondary metabolites in plants. The bioactivities, such as potential antibacterial, insecticidal, and nematicidal effects, have been studied [9,10,11,12,13,14]. The mechanism of naphthoquinone in organisms is related to enhanced reactive oxygen species (ROS) generation and results in the death of cells [15].…”

Juglone-Triggered Oxidative Responses in Seeds of Selected Cereal Agrosystem Plant Species

“…Additionally, a few reports have elucidated that the transport of JU in soil may be significantly enhanced by fungal hyphae, hence modifying its biological effects [44][45]. On the other hand, results of numerous in vitro studies evidenced a strong antimicrobial and antiparasitic impact of JU or extracts derived from walnut tissues [46][47][48][49][50][51][52]. The use of allelopathy phenomenon in crop production is gaining increased recognition, particularly in organic farming.…”