Pharmacophore identification, virtual screening and activity verification of pedunsaponin A on target proteins PcAdv and PcnWAS of Pomacea canaliculata

Target-protein-based pesticide screening has attracted wide-ranging attention on pesticide science. Pedunsaponin A (PA) is a compound isolated from the root of Pueraria peduncularis, and it has a strong toxic effect on Pomacea canaliculata. Previous studies found that Advlin (PcAdv) and neural Wiskott-Aldrich syndrome isoform X1(PcnWAS) are target proteins of PA when interacted with P. canaliculata. In this study, we modeled the two target proteins through I-Tasser and identified the pharmacophore of PA binding to the two target proteins by molecular docking. Furthermore, through virtual screening, potassium alginate was found to strongly bind to the target proteins in theory. In vivo bioassay showed that, similar to PA treatment, potassium alginate was able to induce typical poisoning symptoms on P. canaliculata, which were characterized by abnormal increase of excreta, weakening of climbing capacity, loss of gill cilia and decrease in hemocyanin content, and even cause death of P. canaliculata with a 13.33% mortality rate under 100 mg L^-1 concentration. Furthermore, the treatment of potassium alginate also decreased the gene expression level of PcAdv and PcnWAS. These findings indicate that potassium alginate can affect the living state of P. canaliculata, and that it is feasible to develop new molluscicides based on PcAdv and PcnWAS by virtual screening. © 2022 Society of Chemical Industry.

Safety and efficacy of sodium and potassium alginate for pets, other non food-producing animals and fish

Sodium and potassium alginate are intended to be used as technological additives (functional groups: emulsifiers, stabilisers, thickeners, gelling agents and binders). Sodium alginate is intended to be used in feedingstuffs for pets, other non food-producing animals and fish, with no maximum recommended use level. Potassium alginate is intended to be used in feedingstuffs for cats and dogs at levels up to 40,000 mg/kg feed (on dry matter). Since the functional properties of the additives are determined by the alginate content, sodium and potassium alginate were considered equivalent. The maximum dose considered safe for cats, dogs, other non food-producing animals, salmonids and other fish is 40,000 mg alginates (sodium and potassium salts)/kg complete feed. The use of alginates in feedingstuffs for fish is of no concern for the consumer. Alginates are reported not to be irritant to the skin but mildly irritant to the eyes. They are considered as potential sensitisers to the skin and the respiratory tract. Alginates are high-molecular-weight polymers naturally occurring in brown algae. Their use in feedingstuffs for fish does not pose a risk for the aquatic environment. Alginates are effective as stabilisers, thickeners, gelling agent and binders. No conclusion could be drawn on the efficacy of alginates as emulsifiers.