Infestation of Lithodes santolla by Eremitione tuberculata: spatial and temporal variations in parasite prevalence and effect on host growth.

The southern king crab (SKC) Lithodes santolla is a crustacean parasitised by the bopyrid Eremitione tuberculata. This study aimed to analyse spatial and temporal variations in E. tuberculata prevalence in the juvenile SKC population of San Jorge Gulf (SJG) and adjacent waters (Argentine Patagonia), and evaluate the effects of the parasite on SKC juveniles to improve our understanding of its impact as a disease on SKC health condition. Moult increment and body weight were compared between parasitised and unparasitised individuals. The prevalence of E. tuberculata in SKC juveniles varied both spatially and temporally. In the south of SJG, the prevalence was 54.5% (n = 11). Temporal prevalence analysis revealed values lower than 17.4% in mid SJG during May and September 2015. No significant differences were observed in E. tuberculata prevalence between sexes or among seasons. Eremitione tuberculata had a negative effect on SKC growth (lower body dry mass, moult increment and relative increment rate) in parasitised individuals. We hypothesised that the higher prevalence of E. tuberculata in the south SJG could be attributed to the retention of parasite larvae and the presence of the frontal system in this part of the gulf. The temporal variations could reflect host mortality. Our results suggest that bopyrid infestation may have a more important role than previously believed in the dynamics of the SKC population in mid-Patagonia.

Microplastics and 17α Ethinylestradiol: How Do Different Aquatic Invertebrates Respond to This Combination of Contaminants?

The synthetic hormone 17α ethinyl estradiol (EE2) is a molecule widely used in female contraceptives and recognized as a contaminant of attention (Watch List) in the European Union due to its high consumption, endocrine effects and occurrence in aquatic environments. Its main source of introduction is domestic sewage where it can be associated with other contaminants such as microplastics (MPs). Due to their characteristics, they can combine with each other and exacerbate their isolated effects on biota. This study evaluated the combined effects of microplastics (MPs) and 17α ethinylestradiol (EE2) on two tropical estuarine invertebrate species: Crassostrea gasar and Ucides cordatus. Polyethylene particles were spiked with EE2 and organisms were exposed to three treatments, categorized into three groups: control group (C), virgin microplastics (MPs), and spiked microplastics with EE2 (MPEs). All treatments were evaluated after 3 and 7 days of exposure. Oysters exhibited changes in phase 2 enzymes and the antioxidant system, oxidative stress in the gills, and reduced lysosomal membrane stability after exposure to MPs and MPEs. Crabs exposed to MPs and MPEs after seven days showed changes in phase 1 enzymes in the gills and changes in phases 1 and 2 enzymes in the hepatopancreas, such as disturbed cellular health. The combined effects of microplastics and EE2 increased the toxicity experienced by organisms, which may trigger effects at higher levels of biological organization, leading to ecological disturbances in tropical coastal ecosystems.

Phylogenetic inferences based on distinct molecular markers reveals a novel Babesia (Babesia pantanalensis nov. sp.) and a Hepatozoon americanum-related genotype in crab-eating foxes (Cerdocyon thous).

Piroplasmids and Hepatozoon spp. Are apicomplexan protozoa that may cause disease in several canid species. The present study aimed to expand the knowledge on the diversity of piroplasmids and Hepatozoon in crab-eating foxes (Cerdocyon thous; n = 12) sampled in the Pantanal of Mato Grosso do Sul State, central-western Brazil. PCR assays based on the 18S rRNA were used as screening. Three (25%) and 11 (91.7%) were positive for piroplasmids and Hepatozoon spp., respectively. Co-infection was found in three C. thous. Phylogenetic analyses based on the near-complete 18S rRNA, cox-1 and hsp70 genes evidenced the occurrence of a novel of Babesia spp. (namely Babesia pantanalensis nov. sp.) closely related to Rangelia vitalii and Babesia sp. 'Coco'. This finding was supported by the genetic divergence analysis which showed (i) high divergence, ranging from 4.17 to 5.62% for 18 S rRNA, 6.16% for hps70 and 4.91-9.25% for cox-1 and (ii) the genotype network (which displayed sequences separated from the previously described Piroplasmida species by median vectors and several mutational events). Also, phylogenetic analysis based on the 18S rRNA gene of Hepatozoon spp. positioned the sequences obtained herein in a clade phylogenetically related to Hepatozoon sp. 'Curupira 2', Hepatozoon sp. detected in domestic and wild canids from Uruguay and Hepatozoon americanum. The present study described Babesia pantanalensis nov sp. and Hepatozoon closely related to H. americanum in crab-eating foxes from Brazil. Moreover, the coinfection by piroplasmids and Hepatozoon sp. for the first time in crab-eating foxes strongly suggesting that this wild canid species potentially acts as a bio-accumulate of hemoprotozoan in wild environment.

Treatment and Management of Acinetobacter Pneumonia: Lessons Learned from Recent World Event.

Acinetobacter pneumonia is a significant healthcare-associated infection that poses a considerable challenge to clinicians due to its multidrug-resistant nature. Recent world events, such as the COVID-19 pandemic, have highlighted the need for effective treatment and management strategies for Acinetobacter pneumonia. In this review, we discuss lessons learned from recent world events, particularly the COVID-19 pandemic, in the context of the treatment and management of Acinetobacter pneumonia. We performed an extensive literature review to uncover studies and information pertinent to the topic. The COVID-19 pandemic underscored the importance of infection control measures in healthcare settings, including proper hand hygiene, isolation protocols, and personal protective equipment use, to prevent the spread of multidrug-resistant pathogens like Acinetobacter. Additionally, the pandemic highlighted the crucial role of antimicrobial stewardship programs in optimizing antibiotic use and curbing the emergence of resistance. Advances in diagnostic techniques, such as rapid molecular testing, have also proven valuable in identifying Acinetobacter infections promptly. Furthermore, due to the limited availability of antibiotics for treating infections caused A. baumannii, alternative strategies are needed like the use of antimicrobial peptides, bacteriophages and their enzymes, nanoparticles, photodynamic and chelate therapy. Recent world events, particularly the COVID-19 pandemic, have provided valuable insights into the treatment and management of Acinetobacter pneumonia. These lessons emphasize the significance of infection control, antimicrobial stewardship, and early diagnostics in combating this challenging infection.

Prevalence of microplastics in Peruvian mangrove sediments and edible mangrove species.

Mangrove ecosystems have been hypothesised as a potential sink of microplastic debris, which could pose a threat to mangrove biota and ecological function. In this field-study we establish the prevalence of microplastics in sediments and commercially-exploited Anadara tuberculosa (black ark) and Ucides occidentalis (mangrove crab) from five different zones in the mangrove ecosystem of Tumbes, Peru. Microplastic were evident in all samples, with an average of 726 ± 396 microplastics/kg for the sediment, although no differences between the different zones of the mangrove ecosystem were observed. Microplastic concentrations were 1.6± 1.1 items/g for the black ark and 1.9 ± 0.9 microplastics/g for the mangrove crab, with a difference in the microplastic abundance between species (p < 0.05), and between the gills and stomachs of the crab (p < 0.01). Human intake of microplastics from these species, for the population in Tumbes, is estimated at 431 items per capita per year. The outcomes of this work highlight that the mangrove ecosystem is widely contaminated with microplastics, presenting a concern for the marine food web and food security.

Tomographic evaluation of the glands and lymph nodes of the cervical region in the crab-eating fox (Cerdocyon thous).

The present study aimed to determine references of normality of computed tomographic (CT) images of mandibular and parotid salivary glands (PSGs), medial retropharyngeal and mandibular lymph nodes and thyroid gland of 10 clinically healthy crab-eating foxes, Cerdocyon thous. The location, shape, homogeneity of the parenchyma, and length, height, width and pre- and post-contrast attenuation values were evaluated. The anatomical structures in the crab-eating foxes studied here presented anatomical landmarks similar to those described for domestic dogs, and showed a regular shape and homogenous parenchyma, except for the PSGs, that showed predominantly heterogeneous parenchyma. The thyroid gland topography in the crab-eating fox, though very similar, is not identical to the domestic dog and the presence of isthmus between the lobes was not detected. The values obtained from crab-eating foxes are within the normal range, although in the upper limits of dogs. There was a significant difference in the attenuation values between the right and left lobes of the thyroid gland, being greater in the left thyroid lobe. CT attenuation values ranges for this neotropical canid can be incorporated into routine staging procedures in the veterinary care of the crab-eating foxes. Furthermore, the CT images obtained were similar to those of healthy dogs, and the information obtained can be considered as initial tomographic references of normality in the cervical structures of the crab-eating fox, in order to aid in the diagnosis of future diseases that can affect this neotropical canid.

Serological Survey for Three Canine Viruses in Brazilian Wild Carnivores : Antibodies Against Canine Viruses in Wild Carnivores.

We evaluated the presence of antibodies against CaHV-1, CDV, and CPV-2 in serum samples from Brazilian wild carnivore species. Nine maned wolves and six crab-eating foxes were tested for CaHV-1 and CDV by virus neutralization test and CPV-2 by hemagglutination inhibition assay. Antibodies to CaHV-1, CDV, and CPV-2 were detected in serum samples of 1 (6.7%), 5 (33.3%), and 10 (66.7%) wild carnivores, respectively. Two maned wolves and one crab-eating fox were seropositive simultaneously for CDV and CPV-2. Antibodies against all viruses were detected in one crab-eating fox. This is the first report of CaHV-1 antibody detection in crab-eating foxes.

Neuroethology in South America: past, present and future.

South America is a vast continent endowed with extraordinary biodiversity that offers abundant opportunities for neuroethological research. Although neuroethology is still emerging in the region, the number of research groups studying South American species to unveil the neural organization of natural behaviors has grown considerably during the last decade. In this Perspective, we provide an account of the roots and strategies that led to the present state of neuroethology in the Southern Cone of America, with a forward-looking vision of its role in education and its international recognition. Hopefully, our Perspective will serve to further promote the study of natural behaviors across South America, as well as in other scarcely explored regions of the world.

Persistence of a carbapenem-resistant Acinetobacter baumannii (CRAB) International Clone II (ST2/IC2) sub-lineage involved with outbreaks in two Brazilian clinical settings.

BACKGROUND: Acinetobacter baumannii international clone II (IC2) is a widespread pandemic clone, however, it is rarely described in South America. The present study reported an outbreak caused by XDR IC2 strains in a clinical setting in Rio de Janeiro in 2022. METHODS: Molecular epidemiology analysis was conducted with MLST to determine the clonal relationship and to assign a sequence type. The antimicrobial resistance profile of A. baumannii strains was assessed by the disk-diffusion method and MIC determination, and the presence of antibiotic resistance genes was determined by PCR and Sanger sequencing. The whole genome of one representative strain (AB91) was sequenced to prospect its resistome and virulome. RESULTS: The MLST revealed that all strains belonged to the ST2 (Pasteur scheme) that corresponded to the pandemic IC2 lineage. They presented the XDR phenotype, which was compatible with their resistome composed of several acquired resistance genes and altered housekeeping genes. Additionally, an expressive virulome was revealed in AB91 genome. Genomic comparison with the unique other available IC2 genome from Brazil revealed that outbreaks occurring during (São Paulo - 2020/2021) and after (Rio de Janeiro - 2022) COVID-19 pandemics were caused by the same IC2 lineage. CONCLUSIONS: This study suggests that the presence of a huge arsenal of resistance and virulence genes may have contributed to the persistence and the successful establishment of IC2 in Brazilian clinical settings during and after the COVID-19 pandemics in response to a series of events, such as the antibiotic overused during that period.

A new species of spider of the genus Sadala Simon, 1880 (Araneae, Sparassidae) from the Yasuni Biosphere Reserve, Amazonian lowlands of Ecuador.

We describe a new species of giant crab spider of the genus Sadala Simon, 1880 collected in Lowland Evergreen rainforests at the Tiputini Biodiversity Station, Yasuni Biosphere Reserve, Amazonian Ecuador. This new species corresponds to the first record of the genus from Ecuador. Females of the new species of Sadala are similar to S. punicea and S. nanay, by having the epigyne with a median septum diamond-shaped posteriorly. The new species is easily distinguished from S. punicea and S. nanay by having relatively straight anterior lateral margins of the median septum. This study increases to 10 the number of described species of Sadala.

Describimos una nueva especie de araña cangrejo gigante del género Sadala Simon, 1880 colectada en Bosque Lluvioso Siempreverde de Tierras Bajas en la Estación de Biodiversidad Tiputini, Reserva de la Biósfera Yasuní, Amazonía del Ecuador. Esta nueva especie corresponde al primer registro del género en Ecuador. Las hembras de la nueva especie de Sadala se diferencian de todos sus congéneres, excepto S. punicea y S. nanay, por un septo medio del epiginio con forma de diamante posteriormente. La nueva especie se diferencia fácilmente de S. punicea y S. nanay por tener los bordes anterolaterales del septo medio relativamente más rectos. Este estudio incrementa a diez el número de especies descritas de Sadala.

Outbreak of high-risk XDR CRAB of international clone 2 (IC2) in Rio Janeiro, Brazil.

OBJECTIVES: Among the high-risk clones of Acinetobacter baumannii, called international clones (ICs), IC2 represents the main lineage causing outbreaks worldwide. Despite the successful global spread of IC2, the occurrence of IC2 is rarely reported in Latin America. Here, we aimed to evaluate the susceptibility and genetic relatedness of isolates from a nosocomial outbreak in Rio de Janeiro/Brazil (2022) and perform genomic epidemiology analyses of the available genomes of A. baumannii. METHODS: Sixteen strains of A. baumannii were subjected to antimicrobial susceptibility tests and genome sequencing. These genomes were compared phylogenetically with other IC2 genomes from the NCBI database, and virulence and antibiotic resistance genes were searched. RESULTS: The 16 strains represented carbapenem-resistant A. baumannii (CRAB) with an extensively drug-resistant profile. In silico analysis established the relationship between the Brazilian CRAB genomes and IC2/ST2 genomes in the world. The Brazilian strains belonged to three sub-lineages, associated with genomes from countries in Europe, North America, and Asia. These sub-lineages presented three distinct capsules, KL7, KL9, and KL56. The Brazilian strains were characterised by the co-presence of blaOXA-23 and blaOXA-66, in addition to the genes APH(6), APH(3"), ANT(3"), AAC(6'), armA, and the efflux pumps adeABC and adeIJK. A large set of virulence genes was also identified: adeFGH/efflux pump; the siderophores barAB, basABCDFGHIJ, and bauBCDEF; lpxABCDLM/capsule; tssABCDEFGIKLM/T6SS; and pgaABCD/biofilm. CONCLUSION: Widespread extensively drug-resistant CRAB IC2/ST2 is currently causing outbreaks in clinical settings in southeastern Brazil. This is due to at least three sub-lineages characterised by an enormous apparatus of virulence and resistance to antibiotics, both intrinsic and mobile.

Use of Chitosan from Southern King Crab to Develop Films Functionalized with RGD Peptides for Potential Tissue Engineering Applications.

Southern King Crab (SKC) represents an important fishery resource that has the potential to be a natural source of chitosan (CS) production. In tissue engineering, CS is very useful to generate biomaterials. However, CS has a lack of signaling molecules that facilitate cell-substrate interaction. Therefore, RGD (arginine-glycine-aspartic acid) peptides corresponding to the main integrin recognition site in extracellular matrix proteins have been used to improve the CS surface. The aim of this study was to evaluate in vitro cell adhesion and proliferation of CS films synthesized from SKC shell wastes functionalized with RGD peptides. The FTIR spectrum of CS isolated from SKC shells (SKC-CS) was comparable to commercial CS. Thermal properties of films showed similar endothermic peaks at 53.4 and 53.0 °C in commercial CS and SKC-CS, respectively. The purification and molecular masses of the synthesized RGD peptides were confirmed using HPLC and ESI-MS mass spectrometry, respectively. Mouse embryonic fibroblast cells showed higher adhesion on SKC-CS (1% w/v) film when it was functionalized with linear RGD peptides. In contrast, a cyclic RGD peptide showed similar adhesion to control peptide (RDG), but the highest cell proliferation was after 48 h of culture. This study shows that functionalization of SKC-CS films with linear or cyclic RGD peptides are useful to improve effects on cell adhesion or cell proliferation. Furthermore, our work contributes to knowledge of a new source of CS to synthesize constructs for tissue engineering applications.

Molecular insights from the crab Neohelice memory model.

Memory acquisition, formation and maintenance depend on synaptic post-translational machinery and regulation of gene expression triggered by several transduction pathways. In turns, these processes lead to stabilization of synaptic modifications in neurons in the activated circuits. In order to study the molecular mechanisms involved in acquisition and memory, we have taken advantage of the context-signal associative learning and, more recently, the place preference task, of the crab Neohelice granulata. In this model organism, we studied several molecular processes, including activation of extracellular signal-regulated kinase (ERK) and the nuclear factor kappa light chain enhancer of activated B cells (NF-κB) transcription factor, involvement of synaptic proteins such as NMDA receptors and neuroepigenetic regulation of gene expression. All these studies allowed description of key plasticity mechanisms involved in memory, including consolidation, reconsolidation and extinction. This article is aimed at review the most salient findings obtained over decades of research in this memory model.

Mercury contamination in seafood from an aquatic environment impacted by anthropic activity: seasonality and human health risk.

Petroleum activity and the dumping of domestic and industrial sewage are important sources of mercury (Hg) contamination in the aquatic environment. Thus, this article aimed to biomonitor the Hg concentration in fish, mussels, and swimming crabs of commercial importance in southeastern Brazil. The quantifications were carried out over a year to verify the influence of seasonality. Finally, a risk assessment was applied to identify whether the concentrations found could lead to long-term damage to the population. Our results indicate that the contaminations were higher in spring, summer, and winter than in autumn, mainly among fish and swimming crabs. The results of quantification in the animal and estimated monthly intake, despite being below the limit established nationally and internationally, were indicative of risk for these two animals after calculating the Hazard quotient. The highest risk values were attributed to the infant population. Based on the data generated by this work, the consumption of mussels is encouraged throughout the year, to the detriment of the other types of seafood studied, especially during summer, spring, and winter. Our work reinforces the importance of risk assessment for a more reliable understanding of the impact of contaminants in seafood on the population's health.

Protocolo anestésico em guaxinim submetido à colocefalectomia / Anesthesic protocol in a raccoon submitted to colocephalectomy

Em guaxinins, comumente se observa a presença de osteoartrites acometendo a articulação coxofemoral. Em carnívoros domésticos, o tratamento pode ser conservativo ou cirúrgico e, dentre as técnicas cirúrgicas, cita-se a colocefalectomia. Por ser um procedimento que provoca dor moderada a severa, um protocolo de anestesia balanceada se faz necessário, podendo associar a técnicas de bloqueio locorregional, como a epidural. Protocolos descritos para a espécie são limitados, porém comumente empregados para contenções químicas, avaliações físicas e exames de imagem. Portanto, o objetivo deste trabalho é relatar a o protocolo anestésico realizado em guaxinim (Procyon cancrivorus) submetido à colocefalectomia. Foram utilizados dexmedetomidina (5µg/kg), cetamina (5mg/kg) e diazepam (0,3mg/kg) por via intramuscular como medicação pré-anestésica, indução com propofol e manutenção por anestesia inalatória com isoflurano. Para execução da anestesia epidural, realizou-se uma abordagem na região lombossacral, sendo administrados bupivacaína (1mg/kg) e morfina (0,1mg/kg). Não houve intercorrências e os parâmetros fisiológicos mantiveram-se estáveis. Descartou-se a necessidade de resgate analgésico e a recuperação anestésica foi rápida. Dessa forma, conclui-se que o manejo anestésico proposto promoveu estabilidade hemodinâmica e recuperação satisfatórias para a espécie.

In raccoons, the presence of osteoarthritis affecting the hip joint is commonly observed. In domestic carnivores, the treatment can be conservative or surgical and, among the surgical techniques, colocephalectomy is mentioned. Since it is a procedure that causes moderate to severe pain, a balanced anesthesia protocol is necessary, which can be associated with locoregional block techniques such as the epidural. Protocols described for the species are limited, being commonly used for chemical restraints, physical assessments, and imaging exams. Therefore, this work aims to report the anesthetic protocol performed on a raccoon (Procyon cancrivorus) submitted to colocephalectomy. Dexmedetomidine (5µg/kg), ketamine (5mg/kg), and diazepam (0.3mg/kg) were used intramuscularly as pre-anesthetic medication, in addition to induction with propofol, and the maintenance by inhalational anesthesia with isoflurane. For epidural anesthesia, an approach was performed in the lumbosacral region, with the administration of bupivacaine (1mg/kg) and morphine (0.1mg/kg). There were no complications and the physiological parameters remained stable. The need for analgesic rescue was ruled out and the anesthetic recovery was fast. Thus, it is concluded that the proposed anesthetic management promoted hemodynamic stability and a satisfactory recovery for the species.

Microsatellite Loci of the Atlantic Horseshoe Crab (Limulus polyphemus) Reveal Inter-Localities Genetic Diversity in the Coastal Waters of the Eastern and Northern Yucatan Peninsula.

The American horseshoe crab (Limulus polyphemus) is an economically and ecologically important species, which is currently categorized as endangered in Mexico. L. polyphemus, one of four extant horseshoe crab species that constitute the class Merostomata, is distributed along the Atlantic coastline of the USA from Alabama to Maine and has another population on the coastline of Campeche, Yucatan, and Quintana Roo in the Yucatan Peninsula, Mexico. In the present study, we evaluated the genetic diversity and genetic structure of four separated localities along the coast of the Yucatan peninsula (Champoton, CH; Isla Arena, IA; Rio Lagartos, RL; and Holbox Island, HI), using nine microsatellite-type molecular markers for this species. The aim of this study is to obtain a baseline of the current level of genetic diversity, which would allow the monitoring of important changes over time. Multilocus analyses revealed moderate levels of genetic diversity (He, 0.5230 to 0.6389) and genetic structure within the whole study area (FST 0.025). The population from RL showed limited gene flows, differing significantly from the other sampling sites. The genetic information obtained in this study can support the implementation of management and conservation programs for this species in Mexico.

Following the aridity: Historical biogeography and diversification of the Philodromidae spider genus Petrichus in South America.

Aridity conditions and expansion of arid biomes in South America are closely linked to the onset of Andean orogeny since at least 30 Mya. Among arid-associated taxa, spiders belonging to the genus Petrichus are found along the Andes mountains and across the diagonal of open formations of the Chaco and Cerrado domains. In this contribution, we asked whether Petrichus originated prior to the central Andean uplift and what historical processes have promoted their diversification. We time-calibrated the phylogenetic tree of Philodromidae and estimated the divergence times of Petrichus. Considering phylogenetic uncertainty, we assessed biogeographical hypotheses of the historical events associated with the diversification of these spiders in South America. Petrichus originated along the Pacific coastal deserts in the Central Andes during the Early Miocene. The species likely dispersed from the western to the eastern side of the Andes coincidently with the central Andean uplift. The diversification of these spiders is coeval with the expansion of open grassland formations during the Late Miocene and Early Pliocene. Multiple dispersal events occurred from the Monte desert to southern South America and eastward to Chaco between âˆ¼ 8 and 2.5 Mya. The Andes might have played a role as a corridor favoring geographical range expansions and colonization of new environments. In addition, we also suggest that Philodromidae might have an Oligocene origin or earlier. Future analyses based on further evidence and larger taxon sampling should be carried out to corroborate our findings.

Nutrient compositional variation and interrelationship in the muscle of wild and plastic-reared brachyuran

Edible brachyurans are recognized as a popular source of food due to their delicious taste and nutritional quality. This study investigated the nutrient compositional variation and interrelationship in the muscle of wild and plastic-reared Cardisoma armatum. The plastic-reared crab had 27.81 ± 2.29 g 100 g-1protein while crab from the wild contained 22.45 ± 2.65 g 100 g-1protein. The difference in protein content of plastic-reared and its counterpart from the mangrove swamp was not significantly different(p > 0.05). This is also true of other proximate composition except that wild crabs were slightly higher in both crude fat (2.68 ± 0.35 g 100 g-1) and carbohydrate (5.89 ± 3.05 g 100 g-1). Generally, the total energy contributed due to protein, carbohydrate and fat in the tissues of both wild and plastic-reared C. armatumare similar. In the wild crab, contents of calcium (16083.27 ± 2127.90 mg 100 g-1) and phosphorus (1191.42 ± 199.21) were relatively higher, while contents of magnesium (368.69 ± 111.05 mg 100 g-1), sodium (125.30 ± 11.18 mg 100 g-1) and potassium (87.36 ± 7.27 mg 100 g-1) were relatively higher inplastic-reared crabs. All significant mineral ratios in wild and plastic-reared C. amartumfall within acceptable range. The positive relationship in the nutritional quality indicates that changes in proximate composition are associated with changes in mineral contents of the crab tissue.(AU)

Extraction of chitin from edible crab shells of Callinectes sapidus and comparison with market purchased chitin / Extração de quitina de cascas de caranguejo comestíveis de Callinectes sapidus e comparação com quitina adquirida no mercado

Chitin and its derived products have immense economic value due to their vital role in various biological activities as well as biomedical and industrial application. Insects, microorganism and crustaceans are the main supply of chitin but the crustaceans shell like shrimp, krill, lobsters and crabs are the main commercial sources. Chitin content of an individual varies depending on the structures possessing the polymer and the species. In this study edible crabs shells (Callinectes sapidus) were demineralized and deproteinized resulting in 13.8% (dry weight) chitin recovery from chitin wastes. FTIR and XRD analyses of the experimental crude as well as purified chitins revealed that both were much comparable to the commercially purchased controls. The acid pretreatment ceded 54g of colloidal chitin that resulted in 1080% of the crude chitin. The colloidal chitin was exploited for isolation of eighty five chitinolytic bacterial isolates from different sources. Zone of clearance was displayed by the thirty five isolates (41.17%) succeeding their growth at pH 7 on colloidal chitin agar medium. Maximum chitinolytic activity i.e. 301.55 U/ml was exhibited by isolate JF70 when cultivated in extracted chitin containing both carbon and nitrogen. The study showed wastes of blue crabs can be utilized for extraction of chitin and isolation of chitinolytic bacteria that can be used to degrade chitin waste, resolve environmental pollution as well as industrial purpose.(AU)

A quitina e seus produtos derivados têm imenso valor econômico devido ao seu papel vital em várias atividades biológicas, bem como em aplicações biomédicas e industriais. Insetos, microrganismos e crustáceos são o principal suprimento de quitina, mas a casca dos crustáceos como camarão, krill, lagosta e caranguejo são as principais fontes comerciais. O conteúdo de quitina de um indivíduo varia dependendo das estruturas que possuem o polímero e da espécie. Neste estudo, as cascas de caranguejos comestíveis (Callinectes sapidus) foram desmineralizadas e desproteinizadas, resultando em 13,8% (peso seco) de recuperação de quitina a partir de resíduos de quitina. As análises de FTIR e XRD do bruto experimental, bem como das quitinas purificadas, revelaram que ambas eram muito comparáveis aos controles adquiridos comercialmente. O pré-tratamento com ácido cedeu 54 g de quitina coloidal que resultou em 1.080% da quitina bruta. A quitina coloidal foi analisada para isolamento de 85 isolados bacterianos quitinolíticos de diferentes fontes. A zona de eliminação foi exibida pelos 35 isolados (41,17%) que sucederam seu crescimento a pH 7 em meio de ágar de quitina coloidal. A atividade quitinolítica máxima, ou seja, 301,55 U / ml, foi exibida pelo isolado JF70 quando cultivado em quitina extraída contendo carbono e nitrogênio. O estudo mostrou que resíduos de caranguejos azuis podem ser utilizados para extração de quitina e isolamento de bactérias quitinolíticas que podem ser usadas para degradar resíduos de quitina, resolver a poluição ambiental e também para fins industriais.(AU)

Extraction of chitin from edible crab shells of Callinectes sapidus and comparison with market purchased chitin / Extração de quitina de cascas de caranguejo comestíveis de Callinectes sapidus e comparação com quitina adquirida no mercado

Chitin and its derived products have immense economic value due to their vital role in various biological activities as well as biomedical and industrial application. Insects, microorganism and crustaceans are the main supply of chitin but the crustaceans shell like shrimp, krill, lobsters and crabs are the main commercial sources. Chitin content of an individual varies depending on the structures possessing the polymer and the species. In this study edible crabs’ shells (Callinectes sapidus) were demineralized and deproteinized resulting in 13.8% (dry weight) chitin recovery from chitin wastes. FTIR and XRD analyses of the experimental crude as well as purified chitins revealed that both were much comparable to the commercially purchased controls. The acid pretreatment ceded 54g of colloidal chitin that resulted in 1080% of the crude chitin. The colloidal chitin was exploited for isolation of eighty five chitinolytic bacterial isolates from different sources. Zone of clearance was displayed by the thirty five isolates (41.17%) succeeding their growth at pH 7 on colloidal chitin agar medium. Maximum chitinolytic activity i.e. 301.55 U/ml was exhibited by isolate JF70 when cultivated in extracted chitin containing both carbon and nitrogen. The study showed wastes of blue crabs can be utilized for extraction of chitin and isolation of chitinolytic bacteria that can be used to degrade chitin waste, resolve environmental pollution as well as industrial purpose.

A quitina e seus produtos derivados têm imenso valor econômico devido ao seu papel vital em várias atividades biológicas, bem como em aplicações biomédicas e industriais. Insetos, microrganismos e crustáceos são o principal suprimento de quitina, mas a casca dos crustáceos como camarão, krill, lagosta e caranguejo são as principais fontes comerciais. O conteúdo de quitina de um indivíduo varia dependendo das estruturas que possuem o polímero e da espécie. Neste estudo, as cascas de caranguejos comestíveis (Callinectes sapidus) foram desmineralizadas e desproteinizadas, resultando em 13,8% (peso seco) de recuperação de quitina a partir de resíduos de quitina. As análises de FTIR e XRD do bruto experimental, bem como das quitinas purificadas, revelaram que ambas eram muito comparáveis aos controles adquiridos comercialmente. O pré-tratamento com ácido cedeu 54 g de quitina coloidal que resultou em 1.080% da quitina bruta. A quitina coloidal foi analisada para isolamento de 85 isolados bacterianos quitinolíticos de diferentes fontes. A zona de eliminação foi exibida pelos 35 isolados (41,17%) que sucederam seu crescimento a pH 7 em meio de ágar de quitina coloidal. A atividade quitinolítica máxima, ou seja, 301,55 U / ml, foi exibida pelo isolado JF70 quando cultivado em quitina extraída contendo carbono e nitrogênio. O estudo mostrou que resíduos de caranguejos azuis podem ser utilizados para extração de quitina e isolamento de bactérias quitinolíticas que podem ser usadas para degradar resíduos de quitina, resolver a poluição ambiental e também para fins industriais.