Mussel Research Articles

Do seaweed fronds offer refuge for mussels?

Do seaweed fronds offer refuge for mussels?

The influence of surface waters on the bioavailability and toxicity of copper oxide nanoparticles to freshwater mussels

The increased commercial use of copper oxide nanoparticles (nCuO) led to the release of nanoparticles in wastewaters potentially harming the aquatic biota. The purpose of this study was to determine the toxic action of nCuO and dissolved Cu (II) to Dreissena bugensis freshwater mussels placed in 4 types of surface waters: aquarium, green (high conductivity), brown (high organic carbon) and 10 % municipal effluent (high conductivity and anthropogenic source of organic carbon). Mussels were exposed to 50 µg/L of nCuO or Cu (II) for 96 h at 15 °C in the above waters. The results revealed that the total Cu loadings were higher in mussels placed in organic-rich waters (brown and effluent) and exposed to either forms of Cu. Tissue Cu contents were correlated with air-time survival, lipid peroxidation, protein-ubiquitin levels and DNA strand breaks. Both surface water types and Cu forms influenced Zn (II) mobilization, glutathione S-transferase activity and protein turnover (ubiquitin binding). Based on the surface water properties, Cu (II) was more influenced by the levels and origin of the organic carbon content while nCuO was more influenced by the total suspended solids. In conclusion the toxicity of nCuO could be influenced by surface waters properties expecially when similar physiological targets are impacts by these treatments.

REPRODUCTIVE BIOLOGY OF THE FRESHWATER MUSSEL, NITIA TERETIUSCULA (PHILIPPI, 1847) (BIVALVIA: UNIONIDAE) FROM THE NILE RIVER IN EGYPT

Seasonal reproductive cycle, gonad structure, gametogenesis, larval development and sex ratio of the freshwater mussel, Nitia teretiuscula (Philippi, 1847) was investigated for the first time. A total of 200 mussels, were randomly collected each month from September 2016 to August 2017 from four regions along Nile River, Egypt: El-Kanater (Qaluobiya Governorate), Tura (Helwan Governorate) Geziret Bein El-Bahrein (Giza Governorate) and Geziret El-Dahab (Cairo Governorate). Histological examination of the gonads showed that N. teretiuscula is a dioecious species with a 1:1 sex ratio. The female and male gonads were found to be paired and asymmetrical organs, situated between the mantle and digestive gland. Female follicles contain edoogonia and oocytes that could be separated into, previtelogenin, vitelogenin and postvitelogenin stages. Male follicles contained spermatogonia and spermatocytes that could be classified as primary spermatocytes, secondary spermatocytes and spermatids. Moreover, the reproductive cycle of both sexes included four developmental stages, developing, ripened (mature), spawning and spent. The predominant stages were ripening (mature) and spawning, whereas spent gonads were rare. Gametogenesis began in early spring and spawning occurred in late spring. Although mature oocytes and spermatozoa were present for almost the entire year, gonadal activity seemed lowest in autumn months. Both sexes displayed the most gonadal activity during the winter months. Consequently, eggs and larval stages (glochidia) were incubated for a short period within both the outer and inner demibranchsso; N. teretiuscula can be considered atetragenic and tachytachtic species.

Optimization of the ultrasonic-microwave assisted enzymatic hydrolysis of freshwater mussel meat

In the present study, the Ultrasonic-Microwave (US-MW) technique was applied for assisting enzymatic hydrolysis of freshwater mussel meat. The operating parameters of enzymatic hydrolysis were investigated and the properties and qualities of the freshwater mussel hydrolysates were also analyzed. The considerable optimum conditions for enzymatic hydrolysis of mussel meat were ratio of liquid to material of 10.36:1, power of 360.52 W, processing time of 6.91 min, enzymolysis time of 4 h. Under these conditions, a degree of hydrolysis (DH) of 48.40% was obtained. The hydrolysates produced under optimum conditions, were characterized in terms of electrophoretic profile, amino acid composition and infrared spectrum analysis. SDS-PAGE profiles of the hydrolysates revealed that several protein bands were cleaved and several light myosin chains (25 kDa and 15 kDa, respectively) and peptides of molecular weight lower than 6.5 kDa were identified. The infrared spectrum absorption peak of amide band A and band III shifted after US-MW pre-treatment, which indicated that the N-H (hydrogen bonding) stretching vibration and triple helix structure of samples were affected. The essential amino acids in hydrolysates with or without US-MW pre-treatment were 36.62 mg/100 g and 33.40 mg/100 g. It was proved that US-MW assisted enzymatic hydrolysis is an effective technology to utilize freshwater mussel meat. Keywords: ultrasonic-microwave (US-MW), freshwater mussel meat, enzymatic hydrolysis, degree of hydrolysis (DH) DOI: 10.25165/j.ijabe.20181105.4104 Citation: Zhou Y J, Yi X L, Wang J Y, Yang Q, Wang S J. Optimization of the ultrasonic-microwave assisted enzymatic hydrolysis of freshwater mussel meat. Int J Agric & Biol Eng, 2018; 11(5): 236–242.

Nonconsumptive predator effects on prey: dogwhelk cues limit mussel recruitment and trigger mussel shell plasticity that hinders predation

Nonconsumptive predator effects on prey: dogwhelk cues limit mussel recruitment and trigger mussel shell plasticity that hinders predation

Efecto de la alimentación sobre la condición fisiológica del mejillón Perna viridis (Bivalvia: Mytilidae), según el cociente ARN/ADN

The green mussel, Perna viridis, became widespread in the northern coast of Sucre State since its arrival to Venezuela in 1993. RNA/DNA and Protein/DNA ratios were used to study the effect of starvation on its instantaneous growth. The mussels were collected in La Esmeralda and Chacopata, acclimatized in the labo­ratory for four weeks and maintained for another six weeks in two groups: one fed ad libitum and another with­ out food (this later group was later fed for two additional weeks). Protein (colorimetric method), and nucleic acid concentrations (RNA and DNA, fluorometric method with ethidium bromide) were measured in adductor mus­cle, digestive gland and gills. The instantaneous growth was assessed using RNA/DNA and Protein/DNA rations. These indexes were always higher in the fed organisms. Animals from Chacopata were in better physiological condition that those from La Esmeralda during the abstinence time (six weeks). Muscle was the best tissue to determine instantaneous growth. The RNA/DNA ratio is a reliable index to determine the physiological condition and instantaneous growth of this species.

Extending the toxicity-testing paradigm for freshwater mussels: Assessing chronic reproductive effects of the synthetic estrogen 17α-ethinylestradiol on the unionid mussel Elliptio complanata

Surface water concentrations of the synthetic estrogen 17α-ethinylestradiol (EE2) as low as 1ng/L can cause adverse reproductive effects in fish under acute and chronic exposure conditions, whereas higher concentrations (> 5ng/L) in acute studies are necessary to elicit adverse effects in freshwater mussels. Prolonged chronic exposures of freshwater mussels to EE2 remain un-evaluated. An extended duration testing paradigm was used to examine reproductive and biochemical (carbohydrate, lipid, protein) effects of EE2 on the unionid mussel, Elliptio complanata, throughout its reproductive cycle. Mussels were exposed to a control and EE2 concentrations (5 and 50ng/L) in six discrete and sequential 28 d tests, and in one discrete and simultaneous 180 d test, from February through August. Foot protrusion and siphoning behavior were recorded daily, along with conglutinate releases and larval (glochidia) mortality. Gonad, hemolymph, and gonad fluid samples were taken for biochemical and vitellogenin-like protein (Vtg) analysis post-exposure. Female mussels released eggs and conglutinates during the months of April to June, indicating sexual maturation during this time. Conglutinates released in the 5ng/L treatment in 28 d exposures contained fewer glochidia and more eggs, and increased concentrations of Vtg in hemolymph were observed from April to August in the 5ng/L treatment during the 180 d exposure. Results indicate that the 180 d test approach, concurrent with the sequence of 28 d tests, enabled a more robust evaluation of mussel behavior and physiology than would have been possible with a single short-term (28 d) test.

Effects of exposure to zinc oxide nanoparticles in freshwater mussels in the presence of municipal effluents

Zinc oxide (nano-ZnO) nanoparticles are used in the production of transparent sunscreens and cosmetics, which are released into surface waters and municipal wastewater effluent. The purpose of this study was to examine the toxicity of nano-ZnO in the presence of municipal effluents to freshwater mussels Elliptio complanata. Mussels were exposed for 21 days at 15 o C to nano-ZnO and ZnCl2 in the presence of 10 % dilution of primary-treated municipal effluent. After the exposure period and 24-h depuration step, mussels were analyzed for total Zn in gills and digestive gland, free Zn, metallothioneins (MT), oxidative stress (glutathione S-transferase and LPO), endoplasmic reticulum stress (heat shock proteins and protein ubiquitination) and genotoxicity. The data revealed that although total Zn loadings did not change with these treatments, Zn levels in digestive gland were elevated in mussels exposed to nano-ZnO but not with ZnCl2 in the presence of municipal effluent. Free Zn levels in the gills were elevated in mussels exposed to the municipal effluent, but decreased in mussels exposed to nano-ZnO. MT in digestive gland showed a similar pattern and was negatively associated with free and total Zn. GST activity was significantly reduced by both nano-ZnO and municipal effluent and was negatively correlated with MT levels, suggesting the involvement of MT in the sequestration of reactive oxygen species. Discriminant function analysis showed that the municipal effluent related effects differed from the unexposed mussels and nano-ZnO exposed mussels in terms of the following responses: free Zn in gills and digestive gland and GST activity. Nano-ZnO related effects also involved GST activity, MT and protein ubiquitination, which suggests a combination of oxidative stress and reticulum endoplasmic stress. In respect with oxidative stress, the oxidative properties of nano-ZnO and ZnCl2 are dampened in the presence of the municipal effluent.

Ecological Assessment in Semarang Coastal Area Based on Sediment Bioassay Approach

Rapid development of industry and population growth leads to ecological pressures on coastal areas. Semarang as the capital of Central Java and as a port city has a sensitivity of environment which is important to do. Sediment is an important thing from aquatic environment because acts as sink or source of pollutant and could be used to assess health of coastal environment. Three locations that had been studied were Tanjung Mas Port, estuaries of West Canal Flood and estuaries of East Canal Flood. These locations were compared to assess health of sediment through elutriate - sediment toxicity test. Sediment from each location was exposure to green mussel larvae for 48 hour. Statistical analysis with ANOVA showed that abnormality larvae from sites 5, 8 and 13 are significantly different from other. The highest of abnormality larvae occurred in Port, followed by Eastern Canal Flood and Western Canal Flood. From other study had been reported that Ammonia beccari, bio indicator for hypoxia/anoxia/eutrophic was found in Port. Lead was decreased form Port, East Canal Flood and West Canal Flood, respectively. So, we concluded that sediment quality from Port, West Canal Flood and East Canal Flood are decreased.

Identifying Specialized 19th Century Fishing Camps on California's Northern Channel Islands: Applying AMS Radiocarbon Dating to Historical Sites

California’s Northern Channel Islands have long been an epicenter of specialized fishing economies dating from 13,000 yr ago to the mid-19th century. With thousands of well-preserved shell middens, some dominated by single shellfish species and little to no material culture, it can be difficult to distinguish between specialized prehistoric and historical deposits at some site types. Beginning at least in the Early Holocene and continuing into the Historic period, California mussels, turban snails, and abalone were targeted for specialized collection and processing by Native Americans and later Chinese and Euro-American fishers. Here, we demonstrate how selective accelerator mass spectrometry (AMS) radiocarbon dating of specialized abalone processing camps can help distinguish between prehistoric and historical sites. While unconventional, our case study demonstrates the utility of 14 C dating at sites less than 300 yr old. DOI: 10.2458/azu_rc.57.18397

BULLDOZING AND RESTING TRACES OF FRESHWATER MUSSEL ANODONTA WOODIANA AND SUBSTRATE CHARACTERISTICS IN LAKE-MARGIN AND RIVER SETTINGS OF UMBRIA, ITALY

The neoichnology of the freshwater mussel Anodonta ( Sinanodonta ) woodiana (Lea, 1834) is examined herein in some continental environments of Umbria (central Italy), such as lake-margin and river dam-margin settings. This study, based on analysis of about 200 traces, reveals that this mussel burrows employing two types of behaviours: bulldozing which produces horizontal meanders to straight bilobate traces, often filled with peloidal faecal pellets (pseudofaeces and backfill), and resting (vertical stationary into substrate) while filter feeding. A new type of very soft substrate, the ‘cloudground’ is proposed. It is placed at the water-sediment interface, above the soupground. After four years of observation, the cloudground was buried with shells and traces, preserving through the fossilization barrier about 20% of the Anodonta traces. This bivalve activity is a useful tool to recognize preservation of mud in quiet environments and parallels ichnological evidence of unknown epichnial trace fossils in the continental realm. Cloudground with resting traces must be investigated also in modern marine basin floor environments where cloud of mud dominates and considered also in geological record.

Effects of blue mussel (ME) water extracts on pentobarbital-induced sleep and the sleep architecture in mice

Blue mussel (Mytilus edulis) is a popular shellfish that is used widely in the daily diet. It has antioxidant, antimicrobial, and anticoagulant properties. The hypnotic effects of blue mussel (ME) water extracts in a mouse model were investigated. Oral administration of ME water extracts produced a dose-dependent decrease in sleep latency and an increase in sleep duration in pentobarbital-treated mice. At concentrations of 500 and 1,000 mg/kg, the extracts also increased the sleep onset rate (90 and 90%, respectively) and sleep duration (46.3±4.9 and 58.3±2.0 min, respectively) in sub-hypnotic dosage testing. Electroencephalograms (EEG) and electromyograms (EMG) showed that ME water extracts reduced sleep latency and induced non-rapid eye movement sleep (NREMS) while maintaining rapid eye movement sleep (REMS). ME water extracts did not affect the EEG power density. ME water extract-induced sleep is similar to physiological sleep in a mouse model.

Both trophic and non-trophic interactions determine group structure in the Tatoosh mussel bed

Both trophic and non-trophic interactions determine group structure in the Tatoosh mussel bed

Comparative Assessment of the Mussel Micronucleus Test Versus Bacterial Bioassays for Genotoxicity Testing of Benzo[a]pyrene

Polycyclic aromatic hydrocarbons are hazardous compounds to the environment and human health, thus their detection is an important task. In this study the genotoxic effect of benzo[a]pyrene (B[a]P) was examined on a freshwater mussel Unio pictorum and results were compared to bacterial tests, such as the Ames test and SOS chromotest. The aim of the study was to calibrate the sensitivity of the mussel micronucleus test to that of the two bacterial tests using B[a]P as a reference chemical. The Ames and the micronucleus tests gave similar response both in sensitivity and in concentrationresponse pattern. These two tests are proposed to be applied in a battery for genotoxicity testing.

Observation on fouling organisms collected from Indian naval ships at Bombay

Fouling organisms collected from Indian Naval Ships dry-docked at Bombay during a period of two years (July 1956-June 1958) were studied in detail. Forty six of the forms collected have been identified. The most important groups of ship-fouling Organisms in Bombay waters are Barnacles, Hydroids, Polyzoans and Tube-worms. Eleven different Fouling Communities have been found to dominate the settlements on the hulls at different occasions. Definite zonations that could be observed were restriction of green algae to the boot-top area and mussels and oysters to the pipes and gratings. An attempt has been made to find the sequence of settlement of the different major fouling groups. Some general remarks on the observations have also been included.

Bimonthly assessment of PAH content in wild mussels from the Spanish Atlantic coast

Bimonthly assessment of PAH content in wild mussels from the Spanish Atlantic coast

Lead and other heavy metals (cadmium and mercury) accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas) sampled in Sardinia in 2008-2012

The Sardinian shellfish farming, like the national, is mainly focused on mussels and carpet-shell clams, still less on cupped oyster farming. After Olbia’s Gulf, various lagoon areas along the coastal perimeter have been interested to shellfish farming. They are transitional waters, whose state of pollution must be evaluated both as ecosystem’s health and as directly/indirectly human risk. This also applies to heavy metals such as lead, cadmium and mercury, arising both from anthropogenic that geological-natural activity. The aim of the present study is to investigate the variability of the concentrations of these metals in different mollusks to make a comparative assessment, detect trends (over the five-years or cyclicrecurring) and identify hot spots. In 2008- 2012, 984 samples have been analysed by inductively coupled plasma mass spectrometry technique. Of them, 599 in pre-marketing (for classification of production areas or their monitoring) and the remaining during marketing. The difference between the average levels of the three metals in the different mollusks species was statistically significant, with Pb>Cd>Hg, and there was evidence of a gradual downward trend, albeit moderate, in the contamination levels, with a significant seasonality in concentrations levels, of lead in particular. Also comparisons between the bio-monitored coastal areas were statistically different. Since the samples were representative of the entire production of bivalve mollusks in Sardinia and the contamination allowable limits have never been exceeded in the products marketed, it can be concluded that these products are safe, pointing out that maintenance of monitoring/surveillance plans provides useful information species-dependent, site-specific and temporal trends.

The study of zinc bioaccumulation in internal organs of swan mussel, Anodonta cygnea (Linea, 1876)

Heavy metals as importantpollutants in aquatic ecosystems can cause adverse biological effects on liveorganisms of these environments. This research was conducted to study the bioaccumulationof zinc (Zn) in internal organs (mantle, gill, hepatopancreas and foot) of thefreshwater bivalve, Anodonta cygnea during 27 days in vitro exposureperiod. Results showed that this species has a high potency of metalaccumulation. There was no significant difference between basal Zn levels instudied organs. Maximum accumulation rate were recorded in gill andhepatopancreas and their Zn content was significantly (α=0.05; P < 0.02) higher than mantle and foot. The minimumZn accumulation occurred in mantle. Zn levels in gill, hepatopancreas and footwere increased during exposure period, but a decreasing trend was observed inZn level of mantle between days 18 and 27. The results of this study indicatedthat accumulation potential of different organs and their sensitivity andimpressibility are different and gill and hepatopancreas are appropriate organsto study heavy metal bioaccumulation and their pollution in freshwaters.

How mussels flex for impact

How mussels flex for impact

LATENT EFFECTS OF IRANIAN CRUDE OIL AND A CHEMICAL OIL DISPERSANT ON RED SEA MOLLUSCS

ABSTRACT Predation rate of the gastropod drill, Drupa granulata, on the mussel, Mytilus variabilis, was measured over a period of 28 days after adults from both species had been immersed for 168 h in seawater solutions containing high sublethal concentrations (10 ml/liter) of Iranian crude oil. Predation rate was three times higher in controls than in the group where both predator and prey had been exposed initially; intermediate values were determined among groups where only one species had been treated initially. Fecundity of drills, as evidenced by number of egg cases deposited, was directly related to mussel consumption. In a similar study with a chemical oil dispersant, exposure to high (0.003 ml/liter) sublethal levels for 168 h did not affect markedly the rate at which mussels were destroyed and consumed during post-treatment. However, the fecundity of untreated drills feeding on untreated mussels (controls) was 3 to 10 times greater than among groups in which one or both species had been exposed i...