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This research examined how sodium ascorbate, sodium tripolyphosphate (STPP) and their mixture influence the preservation of snail meat stored at 4 °C for a week, with a focus on commercial use in Thailand. Four treatments were applied to the snail meat: soaking in sodium ascorbate, STPP, a combination of both and a control group. Various quality parameters were analysed. The most effective treatment was the combination of 25.0 g·l-1 sodium ascorbate and 25.0 g·l-1 STPP, which enhanced pH stability, minimized Kvalues, total volatile basic nitrogen and panisidine values, reduced microbial growth and maintained the amino acid profile. Additionally, this treatment lowered biogenic amines and certain acids, indicating the suppression of enzymatic and microbial activities. This study suggested that the combined treatment could be a viable procedure for maintaining the quality and shelf life of snail meat in cold storage, presenting significant contribution to Thailand's seafood industry and the development of efficient preservation methods for seafood. [ABSTRACT FROM AUTHOR]

The Euconulidae is a globally distributed land snail family but there is no record of this family from Thailand. In this study, we describe a new genus, Siamoconus gen. nov., based on comparative studies of the shell characteristics, external morphology of animals, radula, genital and spermatophore structures, and molecular phylogeny. We performed phylogenetic analyses of two mitochondrial gene fragment (cytochrome c oxidase I, COI; and 16S rRNA) and one nuclear (28S rRNA) gene fragment to clarify the relationships with other euconulid genera and its position in the superfamily Trochomorphoidea. We also analysed shell morphometrics, male genitalia and mantle pigmentation of Siamoconus gen. nov., confirming the status of three new species with keeled shells (S. boreas sp. nov., S. coleus sp. nov. and S. geotrochoides sp. nov.) and one new species with a rounded shell (S. destitutus sp. nov.). These new species are restricted to limestone areas in northern and north-eastern Thailand. We also re-examined the status of other genera in the superfamily Trochomorphoidea based on shell features, body pigmentation, radula, genital anatomy, spermatophore morphology, and a phylogenetic analysis of all available trochomorphoidean DNA sequences. Our analysis suggests that the family Geotrochidae, previously synonymised with the Trochomorphidae, should be resurrected to represent the genus Geotrochus from Borneo, and this family is retrieved as the sister clade of the Dyakiidae. ZooBank: urn:lsid:zoobank.org:pub:C5205F4E-5DDE-42E6-A532-761CAFE099C3 Euconulidae is one of the most diverse families in the superfamily Trochomorphoidea with a distribution that is almost world-wide but there is no record of this family from Thailand. We describe four new species of Siamoconus gen. nov., a new euconulid genus and also perform phylogenetic analyses of one nuclear and two mitochondrial gene fragments to clarify the systematic position of this new genus and the relationships to other genera in the superfamily Trochomorphoidea. In addition, the family Geotrochidae, previously synonymised with the Trochomorphidae, is resurrected as sister clade of the Dyakiidae within the superfamily Trochmorphoidea. [ABSTRACT FROM AUTHOR]

Acne vulgaris is a common skin disease mainly caused by the Gram-positive pathogenic bacterium, Propionibacterium acnes. This bacterium stimulates the inflammation process in human sebaceous glands. The giant African snail (Achatina fulica) is an alien species that rapidly reproduces and seriously damages agricultural products in Thailand. There were several research reports on the medical and pharmaceutical benefits of these snail mucus peptides and proteins. This study aimed to in silico predict multifunctional bioactive peptides from A. fulica mucus peptidome using bioinformatic tools for the determination of antimicrobial (iAMPpred), anti-biofilm (dPABBs), cytotoxic (ToxinPred) and cell-membrane-penetrating (CPPpred) peptides. Three candidate peptides with the highest predictive score were selected and re-designed/modified to improve the required activities. Structural and physicochemical properties of six anti-P. acnes (APA) peptide candidates were performed using the PEP–FOLD3 program and the four previous tools. All candidates had a random coiled structure and were named APAP-1 ori, APAP-2 ori, APAP-3 ori, APAP-1 mod, APAP-2 mod, and APAP-3 mod. To validate the APA activity, these peptide candidates were synthesized and tested against six isolates of P. acnes. The modified APA peptides showed high APA activity on three isolates. Therefore, our biomimetic mucus peptides could be useful for preventing acne vulgaris and further examined on other activities important to medical and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Trematodes belonging to the family Echinostomatidae are food-borne parasites which cause echinostomiasis in animals and humans. This is a global public health issue, particularly in East and Southeast Asia. A method to detect the infective stage of Echinostomatidae species is required to prevent transmission to humans. In this study, a loop-mediated isothermal amplification coupled with a lateral flow dipstick (LAMP-LFD) assay was developed for visual detection of the metacercarial stage in edible snails of the genus Filopaludina from local markets in Thailand. The LAMP-LFD method can be performed within 70 min at a consistent temperature of 66 °C, and the results can be interpreted with the naked eye. The detection limits of the assay using Echinostoma mekongi , E. macrorchis , E. miyagawai and Hypoderaeum conoideum genomic DNA were equal between the four species at 50 pg/μL. A specificity evaluation demonstrated that the LAMP-LFD assay had no cross-reaction with another parasite (Thapariella species) or with the snail host species (Filopaludina martensi martensi , F. sumatrensis speciosa , and F. s. polygramma). Clinical test assessments were compared to microscopic examination in 110 edible snail samples. The clinical sensitivity and specificity of the tests were 84.62 % and 100 %, respectively, with a strong level of agreement based on the kappa statistic and the results of both methods were not significantly different (p > 0.05) per McNemar's test. The test successfully developed in this study may be useful for the detection of the metacercarial stage in edible snails for epidemiological investigations, control, surveillance, and to prevent future echinostomiasis health issues. • The assay can amplify DNA of four Echinostomatidae species in a single tube. • The results can be obviously visualized with the naked eye. • The assay could be utilized to diagnose Echinostomatidae infection in edible snail. • This study is the first LAMP-LFD assay for Echinostomatidae detection. [ABSTRACT FROM AUTHOR]

Thai terrestrial microsnails in the genus Aulacospira Möllendorff, 1890 are revised based on the collection of the Zoological Research Collection, Burapha University, Chonburi Province, Thailand and recently collected material. Three new species are described: Aulacospira nutadhirai sp.nov. from Southern Thailand, and Aulacospira tekavongae sp.nov. and Aulacospira vanwalleghemi sp. nov. from Eastern Thailand. The radula and genital system are described, and a key to Thai species is presented. [ABSTRACT FROM AUTHOR]

The lesser-known Sundaic lance-headed pit vipers Trimeresurus wiroti (Malaysia) and Trimeresurus puniceus (Indonesia) contribute to the disease burden of snakebite envenomation in Southeast Asia, but their venom toxicity and neutralization remain insufficiently investigated. This study demonstrated that both venoms were procoagulant (involving thrombin-like activity), hemorrhagic, and lethal to mice, with T. wiroti venom being more lethal (LD 50 = 0.78 μg/g c.f. 1.21 μg/g). The hetero-specific antivenom from Thailand, Green Pit Viper Antivenom (GPVAV, raised against Trimeresurus albolabris) cross-reacted with T. wiroti and T. puniceus venoms with a higher efficacy of immunological binding activity for the latter. The antivenom was also effective in cross-neutralizing the procoagulant, hemorrhagic and lethal effects of the venoms. In lethality neutralization, GPVAV showed a potency of 0.79–1.05 mg venom per mL antivenom, corresponding to the complete neutralization of approximately 8–10 mg venom per unit vial of antivenom for T. wiroti and T. puniceus venoms. Taken together, it was inferred that T. wiroti , T. puniceus , and T. albolabris venoms share common toxin epitopes, thus enabling the cross-neutralization observed. These findings suggest that GPVAV may be potentially useful in the management of envenomation by T. wiroti and T. puniceus while awaiting clinical trial and validation. Image 1 • Lesser-known Trimeresurus wiroti and Trimeresurus puniceus venoms were studied. • Both venoms exhibited procoagulant, hemorrhagic and lethal activities. • Thai Green Pit Viper Antivenom (GPVAV) cross-reacted with the venoms. • GPVAV effectively cross-neutralized the hemotoxic and lethal effects of the venoms. • GPVAV may be potentially useful in treating T. wiroti and T. puniceus envenomings. [ABSTRACT FROM AUTHOR]

The Asian freshwater snail Melanoides tuberculata has been established since the 1960s in the Americas, where it transmits cercariae of a small number of digenetic trematode species from its native range. In 2021–2022, 24 M. tuberculata were discovered shedding transversotrematid cercariae in Puerto Rico, where parasites of this snail have not been previously studied. Adult transversotrematids (in some cases, gravid) were found on field-caught fish and on fish exposed to shedding snails, including on fish species native to Puerto Rico. Adults and cercariae were identified as Transversotrema patialense (Soparkar, 1924), a species native to the Indomalayan region. Morphological identification was supported with 28S rDNA sequences closely matching that from unidentified transversotrematid cercariae in Thailand. The absence of T. patialense in snails collected prior to 2021, increasing prevalence of infection in snails collected thereafter, and lack of variation in parasite DNA sequences (28S, internal transcribed spacer 2, cytochrome c oxidase I) from three isolates are consistent with a recently introduced and possibly expanding parasite population. Transversotrema patialense has been recorded outside its native range before, but most studies (including a prior record in the Americas) reported the parasite from captive hosts from commercial sources such as pet shops. The present results thus provide the first demonstration of natural transmission of T. patialense in the Americas. Phylogenetic analysis of 28S but not of ITS2 show the transversotrematid genus Transversotrema Witenberg, 1944 is paraphyletic, with Crusziella Cribb, Bray and Barker 1992 nested within it. [Display omitted] • The Indomalayan parasite Transversotrema patialense was found in Melanoides tuberculata in Puerto Rico. • Partial 28S links T. patialense in Puerto Rico to unidentified cercaria in native range in Thailand. • Experimental infections and field collections show native fish are competent hosts. • Phylogeny of 28S but not of ITS2 shows Crusziella nested within Transversotrema. • Size of adult T. patialense is correlated with size of fish scales. [ABSTRACT FROM AUTHOR]

The two venomous pit vipers, Trimeresurus macrops and T. hageni, are distributed throughout Thailand, although their abundance varies among different areas. No species-specific antivenom is available for their bite victims, and the only recorded treatment method is a horse antivenom raised against T. albolabris crude venom. To facilitate assessment of the cross-reactivity of heterologous antivenoms, protein profiles of T. macrops and T. hageni venoms were explored using mass-spectrometry-based proteomics. The results show that 185 and 216 proteins were identified from T. macrops and T. hageni venoms, respectively. Two major protein components in T. macrops and T. hageni venoms were snake venom serine protease and metalloproteinase. The toxicity of the venoms on human monocytes and skin fibroblasts was analyzed, and both showed a greater cytotoxic effect on fibroblasts than monocytic cells, with toxicity occurring in a dose-dependent rather than a time-dependent manner. Exploring the protein composition of snake venom leads to a better understanding of the envenoming of prey. Moreover, knowledge of pit viper venomics facilitates the selection of the optimum heterologous antivenoms for treating bite victims. [ABSTRACT FROM AUTHOR]