Ciguatoxin-like toxin in mackerel <i>Acanthocybium soladria</i> in Vietnam

Two processed mackerel products were sent to VAST keylab on “Food and Environmental Safety” in Institute of Oceanography for Ciguatoxin criteria as exported seafood requirement. The specimens were caught from offshore region of Vietnam South-Eastern sea in April 2019. By DNA sequencing of COI gene, both specimens were identified as Acanthocybium solandri, one of high commercial mackerel species which is well-known to be distributed in Central and South-Eastern sea of Vietnam. In mouse bioassay, both extracts from 2 samples exhibited acute toxicity, which killed tested mice within 6 and 15 hours after i.p. injection. In SIM LC/MS-MS analysis, the extracts showed the peak with retention time closed to that in CTX-1B standard in both cases of optimized and non-optimized solid phases. The result suggested that at least there was occurrence of CTX-like toxin in these mackerel specimens. The equivalent toxin levels were estimated as 0.51 ng/g and 0.84 ng/g; 5 and 8 times higher than regulation limit for CTXs in seafood product (0.1 ng CTX-1B/g). Further verification is in progress to confirm toxin in these mackerel samples in Vietnam. However, this data is the first alert on potential poisoning by consumption of mackerel, not only in Vietnam but also in Asia.

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The Phylogenetic Analysis of Cimex hemipterus (Hemiptera: Cimicidae) Isolated from Different Regions of Iran Using Cytochrome Oxidase Subunit I Gene

Journal of Arthropod-Borne Diseases ◽

10.18502/jad.v14i3.4557 ◽

2020 ◽

Author(s):

Awat Samiei ◽

Mousa Tavassoli ◽

Karim Mardani

Keyword(s):

Dna Sequencing ◽

Cytochrome Oxidase ◽

Blood Feeding ◽

Coi Gene ◽

Sequencing Analysis ◽

Nucleotide Polymorphisms ◽

Bed Bugs ◽

Geographical Regions ◽

Dna Sequencing Analysis ◽

I Gene

Background: Bedbugs are blood feeding ectoparasites of humans and several domesticated animals. There are scarcity of information about the bed bugs population throughout Iran and only very limited and local studies are available. The aim of this study is to assess the phylogenetic relationships and nucleotide diversity using partial sequences of cytochrome oxidase I gene (COI) among the populations of tropical bed bugs inhabiting Iran. Methods: The bedbugs were collected from cities located in different geographical regions of Iran. After DNA extraction PCR was performed for COI gene using specific primers. Then DNA sequencing was performed on PCR products for the all 15 examined samples. Results: DNA sequencing analysis showed that the all C. hemipterus samples were similar, despite the minor nucleotide variations (within the range of 576 to 697bp) on average between 5 and 10 Single nucleotide polymorphisms (SNPs). Subsequently, the results were compared with the database in gene bank which revealed close similarity and sequence homology with other C. hemipterus from other parts of the world. Conclusion: In conclusion, this study has demonstrated the ability of the COI gene to differentiate between the C. hemipterus populations from a few different locations in Iran. The current research is the first report of phylogenetic and genetic species diversity analysis conducted on C. hemipterus in Iran. These results provided basic information for further studies of molecular epidemiology, public health and pest control operators in Iran.

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Spinosyns Delivered in Sugar Meals to Aedes aegypti and Aedes albopictus (Diptera: Culicidae): Acute Toxicity and Subacute Effects on Survival, Fecundity, and Fertility

Journal of Medical Entomology ◽

10.1093/jme/tjab220 ◽

2022 ◽

Author(s):

Abdullah A Alomar ◽

Barry W Alto ◽

Edward D Walker

Keyword(s):

Acute Toxicity ◽

Aedes Aegypti ◽

Aedes Albopictus ◽

Nutritive Value ◽

Mosquito Control ◽

Environmental Safety ◽

Adult Mosquito ◽

Hatch Rate ◽

Median Lethal Concentrations ◽

Males And Females

Abstract Sugar is an essential source of nutrition for adult mosquitoes to acquire energy. Toxic sugar bait (TSB) provides a promising method for mosquito control by incorporating toxins into artificial sources of sugar (i.e., toxic baits) presented to wild populations. Spinosyns comprise a family of bacterial secondary metabolites with a unique mode of action against the insect nervous system, an appealing environmental safety profile, and potential for incorporation into sugar baits. This research evaluated acute and subacute effects of spinosad (spinosyns A and D) and spinetoram (spinosyns J and L) in sugar meals on survival, fecundity, and fertility of Aedes aegypti and Aedes albopictus. Acute toxicity of spinosyns doubled from 24 to 48 h of assessment, revealing a relatively slow and cumulative action of the formulated spinosyns. Median lethal concentrations at 48 h were lower for spinetoram than for spinosad, lower for Ae. albopictus than Ae. aegypti, and lower for males than females. When exposed to subacute LC50 concentrations of spinosad and spinetoram for 24 h, survival of males and females of both species was diminished compared with controls, fecundity of females was increased, but fertility as measured by hatch rate of eggs was decreased. The formulations may have increased the nutritive value of the sugar meals thereby boosting fecundity, while toxifying embryos, reducing fertility. The inclusion of subacute effects of spinosyns allows assessment of the broader consequences of TSB for adult mosquito control.

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Molecular Characterization of Clistobothrium sp. Viable Plerocercoids in Fresh Longfin Inshore Squid (Doryteuthis pealeii) and Implications for Cephalopod Inspection

Pathogens ◽

10.3390/pathogens9070596 ◽

2020 ◽

Vol 9 (7) ◽

pp. 596 ◽

Cited By ~ 1

Author(s):

Lisa Guardone ◽

Alice Giusti ◽

Ewa Bilska-Zajac ◽

Renato Malandra ◽

Miroslaw Różycki ◽

...

Keyword(s):

Life Cycle ◽

Cytochrome C Oxidase ◽

Molecular Characterization ◽

Large Subunit ◽

Coi Gene ◽

Rrna Gene ◽

Intermediate Hosts ◽

Lsu Rrna Gene ◽

Seafood Product

Cephalopods, an appreciated seafood product, are common hosts of marine cestodes. The aim of this work is to report visible alive plerocercoids in longfin inshore squid (Doryteuthis pealeii), a cephalopod species commercialized as fresh and whole in Italy. Seventy D. pealeii from the Northwest Atlantic (FAO area 21) were collected and visually inspected. In total, 18 plerocercoid larvae were found in the viscera of 10 host specimens (P: 14.3% 95% CI 7.1–24.7; MI: 1.8, MA: 0.26; range 1–4) and molecularly analyzed targeting the variable D2 region of the large subunit (LSU) rRNA gene and the cytochrome c oxidase subunit I (COI) gene. The molecular characterization allowed to identify all the plerocercoids as Clistobothrium sp., a cestode of the Phyllobothriidae family with Lamnidae sharks as definitive hosts, and cephalopods as second intermediate hosts. These findings represent the first molecular record of Clistobothrium sp. in D. pealeii, thus contributing to elucidate its poorly known life cycle. Even if not affecting consumer’s health, these visible parasites may represent a reason for disgust for consumers. Therefore, the results suggest that Food Business Operators should also check for the presence of these visible parasites during inspection and underline the importance of a correct consumers’ education.

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Using high-resolution melting to identify Calliphoridae (blowflies) species from Brazil

PeerJ ◽

10.7717/peerj.9680 ◽

2020 ◽

Vol 8 ◽

pp. e9680

Author(s):

Pablo Viana Oliveira ◽

Francine Alves Nogueira de Almeida ◽

Magda Delorence Lugon ◽

Karolinni Bianchi Britto ◽

Janyra Oliveira-Costa ◽

...

Keyword(s):

High Resolution ◽

Dna Sequencing ◽

High Resolution Melting ◽

Coi Gene ◽

Morphological Identification ◽

Mitochondrial Coi ◽

New Methods ◽

Degraded Samples ◽

Sequencing Technique ◽

Coi Sequences

Forensic entomology is the study of insects and other arthropods used in the solution of crimes. Most of entomological evidences strongly depend on accurate species identification. Therefore, new methods are being developed due to difficulties in morphological identification, including molecular methods such as High-Resolution Melting. In this study, we reported a new HRM primer set to identify forensically important Calliphoridae (blowflies) from Brazil. For such purpose, Calliphoridae species of forensic importance in Brazil were listed and confirmed by specialists. Mitochondrial COI sequences of those species were downloaded from databases and aligned, and polymorphic variations were selected for distinction between species. Based on it, HRM primers were designed. Forty-three fly samples representing six species were tested in the HRM assay. All samples had the COI gene sequenced to validate the result. Identifying and differentiating the six species proposed using a combination of two amplicons was possible. The protocol was effective even for old insect specimens, collected and preserved dried for more than ten years, unlike the DNA sequencing technique that failed for those samples. The HRM technique proved to be an alternative tool to DNA sequencing, with advantage of amplifying degraded samples and being fast and cheaper than the sequencing technique.

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Genetic variation of reef-building polychaete Sabellaria chandraae in the south-eastern Arabian Sea based on mitochondrial COI gene sequences

Mitochondrial DNA Part B ◽

10.1080/23802359.2019.1673223 ◽

2019 ◽

Vol 4 (2) ◽

pp. 3291-3292 ◽

Cited By ~ 1

Author(s):

Periasamy Rengaiyan ◽

Baban Ingole

Keyword(s):

Genetic Variation ◽

Arabian Sea ◽

Coi Gene ◽

Gene Sequences ◽

The South ◽

Mitochondrial Coi ◽

South Eastern ◽

Mitochondrial Coi Gene ◽

Eastern Arabian Sea

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Advancing traceability using DNA sequence on seafood product: fraudulence in shrimp crackers

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d211222 ◽

2020 ◽

Vol 21 (12) ◽

Author(s):

Mala Nurilmala ◽

YOGHI AJITAMA ◽

AGOES M. JACOEB ◽

AFKAR RONA INDARWATI ◽

RONI NUGRAHA

Keyword(s):

Dna Sequence ◽

Control Method ◽

Gc Content ◽

Pcr Primers ◽

Morphological Characters ◽

Coi Gene ◽

Universal Primers ◽

Unidentified Species ◽

Polymerase Chain ◽

Seafood Product

Abstract. Nurilmala M, Atjitama Y, Jacob AM, Indarwati AR, Nugraha R. 2020. Advancing traceability using DNA sequence on seafood product: fraudulence in shrimp crackers. Biodiversitas 21: 5650-5656. Shrimp crackers are snacks made from starch with the addition of shrimp and other ingredients. Authentication of shrimp crackers becomes a quality control method in line with its traceability since the morphological characters are not recognized in those products. The failure of the authentication will lead to adulteration of shrimp products. The study aimed to design shrimp-specific polymerase chain reaction (PCR) primers by and used them to authenticate shrimp cracker products to assure their traceability. The primers were designed from cytochrome oxidase subunit I (COI) gene with a GC content of 50% and a melting temperature of 57 °C. The amplicon had a length of 613 bp. Fourteen shrimp crackers having DNA concentrations 0.3 to 8.1 ng/µL were evaluated. Eight out of fourteen DNA samples were successfully amplified using the specific primer and could be visualized on the agarose gel at 500-750 bp. Those DNA samples were identified belonging to shrimp species, namely Litopenaeus vannamei, Metapenaeus ensis, and Fenneropenaeus merguiensis with 95% to 100% identity. Meanwhile, the other six DNA samples underwent PCR using universal primers. One sample was amplified and identified as fish (Sphyraena flavicauda). These results indicate illegal substitution of shrimp using unidentified species occurred in shrimp crackers.

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Imaging polymers, proteins and dna in aqueous solutions with the atomic force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152136 ◽

1989 ◽

Vol 47 ◽

pp. 32-33

Author(s):

S.A.C. Gould ◽

B. Drake ◽

C.B. Prater ◽

A.L. Weisenhorn ◽

S.M. Lindsay ◽

...

Keyword(s):

Amino Acids ◽

Dna Sequencing ◽

Aqueous Solutions ◽

Atomic Force Microscope ◽

Piezoelectric Crystal ◽

Atomic Force ◽

Structure Of Molecules ◽

Optical Lever

The atomic force microscope (AFM) is an instrument that can be used to image many samples of interest in biology and medicine. Images of polymerized amino acids, polyalanine and polyphenylalanine demonstrate the potential of the AFM for revealing the structure of molecules. Images of the protein fibrinogen which agree with TEM images demonstrate that the AFM can provide topographical data on larger molecules. Finally, images of DNA suggest the AFM may soon provide an easier and faster technique for DNA sequencing.The AFM consists of a microfabricated SiO2 triangular shaped cantilever with a diamond tip affixed at the elbow to act as a probe. The sample is mounted on a electronically driven piezoelectric crystal. It is then placed in contact with the tip and scanned. The topography of the surface causes minute deflections in the 100 μm long cantilever which are detected using an optical lever.

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