B. bacciger on this bivalve species was investigated and it was shown that it could have a deleterious effect . In France, this bivalve is not specifically monitored unless mortalities are reported. Thus, in 2010 and 2011, severe mortality events occurred on different wedge clam beds in France and analyses revealed the presence of micro- cell parasites belonging to Mikrocytos in the different sampled areas. This was the first time that Mikrocytos parasites were detected in France and the first occurrence of these parasites in this bivalve species. With this detection, several questions arose including: what is the relative taxonomic position of these para- sites? Are they new species or known species? What is their role in observed mortality? In order to answer these questions, we characterized these parasites on the basis of morphological, ultrastructural and molecular criteria, and also by including host information as sug- gested by Abbott & Meyer . The data obtained allowed us to provide a detailed description of two new species, Mikrocytos veneroïdes n. sp. and M. donaxi n. sp., detected during mortality events of the wedge clam Donaxtrunculus in France. We also discussed about the simultaneous apparition of these two different parasites in very close locations and their potential role in D. trunculus mortality.
Abstract— The aim of the present work was to investigate bioaccumulation and biological responses of Donaxtrunculus collected along the sampling area of Aghroud beach (Moroccan south). Samples were collected over a 27-month period in 2009–2011. The study focused on mercury (Hg) as a trace element known to be potential reactive oxygen species inducers. Enzymatic activities related to cellular defense systems including antioxidant enzymes as catalase (CAT) and Acetylcholinesterase (AChE) were measured in soft tissue. Concentrations of mercury were significantly higher in Donaxtrunculus in three months during sampling period. The values are respectively of 0.51 ± 0.02 μg/g wet weight at May 2009; 0.73 ± 0.008 μg /g wwt at September 2009 and 1.43 ± 0.009 μg/g wwt at August 2010. These values exceeded the environmental quality standards (0.5 mg kg−1 wwt) established by the European Union commission. Concerning this study, no significant correlation was observed between mercury and biochemical parameters measured in D. trunculus.
A total of 12 surveys (hand dredge tow) were conducted throughout the sampling period. It appears that a highest value 28502.11 g in autumn and the lowest 8451.58 g in summer, with total catch 78041.92 g (Table 3). Nine different bivalve species were captured during sampling. The following bivalve species were collected throughout this period; Donaxtrunculus, Chamelea gallina, Donax variabilis, Tapes phillippinarum, Tapes decussatus, Venus verrucosa, Spisula subtruncata, Cardium edule and Mytilus galloprovincialis. The catch composition comprised target species (D. trunculus) 69.34%, by-catch bivalve species 25.71%, and predator species 4.95% (Table 3). C. gallina was the most abundant by-catch bivalve species, representing 27.77% of the total catch.
Abstract— Wastewater treatment plants (WTP) are common sources of a wide mixture of chemicals entering the aquatic environment. We have investigated the impact of WTP on two populations of Donaxtrunculus situated outside of the WTP outfall by using antioxidant stress parameters (catalase (CAT) and Gluthation S-transférases (GST)), Acetylcholinesterase (AchE) and malondialdehmyd (MDA). In addition, we have determined the distribution of the species along the Bouadisse beach. AchE, Oxidative damage and antioxidant enzymes had discerned the effect of the wastewater primary treated. The density showed also clear cut distribution in relationship with distance from the WTP outfall. The sites situated in the proximity of WTP outfall and the southernmost site showed decreased densities.
Öz: Araştırmada, Marmara Denizi’nin batısında doğal stokların bulunduğu alanlardan örneklenen beyaz kum midyesi (Chamelea gallina) ve kum şırlanının (Donaxtrunculus) büyüme özellikle- ri tahmin edilmiştir. Numuneler, ticari avcılığa kapalı bölgelerden 24 ay süre ile aylık olarak dreç yardımıyla toplanmıştır. C. gallina populasyon unda bireylerin, boy dağılımı 7 -39 mm, ağırlığı 0.3 -21.05 g olarak belirlenmiş, D. trunculus’un ise boyu 11.5- 42 mm ve ağırlığı 0.26 - 17.22 g arasında değişmiştir. Her iki türün de negatif allometrik büyüme gösterdiği tespit edil- miştir. C. gallina bireylerinin ortalama et verimi %19.10; D. trunculus’un ise %19.45 olarak belirlenmiştir.
El descenso de producción de coquina en las costas gallegas podría relacionarse con la sobreexplotación a la que se ha visto sometida esta especie. Sin embargo, existen otros factores que podrían estar implicados como los movimientos de arena después de fuertes temporales, la realización de construcciones próximas (como paseos marítimos) que alteran el funcionamiento ecológico del banco o el tipo de sustrato de éste, entre otros. Estudios recientes (Marie et al., 2016; Urra et al., 2017) ponen de manifiesto que el descenso en la producción de coquina no es únicamente un problema en Galicia sino también en otras regiones del sur de la Península Ibérica. Por ello, existe un gran interés en la recuperación y gestión de los bancos naturales de D. trunculus para lo cual son importantes los estudios genéticos que permitan caracterizar y evaluar la variación genética de este recurso con el objetivo de obtener datos que permitan evitar la pérdida de variabilidad genética y mejorar su gestión sostenible (Allendorf et al., 2008). Para ello, aparte de estudiar la diversidad y diferenciación poblacional de la especie también se podrían realizar programas de mantenimiento de las condiciones óptimas de su hábitat para aumentar las posibilidades de que los estudios genéticos resulten satisfactorios, así como, la recuperación de la especie a través de prácticas de cultivo en criadero (Ward, 2006).
Formally the phenotype is an expression of the genotype and the environment in which it grows, including structural traits (e.g., plant height, leaf area index, lodging, crop canopy cover), canopy spectral texture (spectral features), physiological traits (e.g., chlorophyll, biomass, pigment content, photosynthesis), abiotic/biotic stress indicators (e.g., stomatal conductance, canopy temperature difference, leaf water potential, and senescence index), nutrients (nitrogen concentration, protein content), and yield . Many of these traits can be used as indicators of plant fitness and for biomass estimation and have been used in selective plant breeding for decades. An important feature of these measurements is they often require manual measurement or sampling. This is invariably time consuming, can result in considerable crop disturbance and for some measurements requires destructive sampling. Thus, any non‐invasive and non‐destructive measurements which can be used as an indicator of likely biomass that can readily be applied to a biomass crop would be advantageous. Crop height is recognized as one of the most important components of AGB and yield in biomass crops [6,7]. Height can be reduced by environmental stress and can therefore be used to separate drought sensitive from drought tolerant crops [8,9]. Traditionally, crop height and diameter are measured manually with graduated poles and measuring tapes; this is difficult to do without canopy disturbance in the central region away from plot edges of tall (3.2 to 4.2 m) A. donax plants with their typically high shoot density. In terms of the choice of sensor, light detection and ranging (LiDAR) is a promising technology to measure plant height and predict biomass . LiDAR equipped UAVs have been demonstrated to work well in forestry [11,12], maize , and shorter annual crops such as wheat . There is one study using tractor mounted LiDAR to characterize a bioenergy crop, Miscanthus giganteus, with good results (reported accuracy 92–98.2%) . However, the approach is limiting in terms of field size and shape as well as crop horizontal density, thus demonstrating the advantage of UAV platforms. Prior to our study, there was no survey that has applied UAV‐based LiDAR to A. donax which contrasts both in terms of crop structure and leaf reflectivity with other crops studied to date.
During combustion, nitrogen is practically fully converted into gaseous N 2 and NO x , which presents the main environmental impact of biomass burning process (García et al., 2012). As can be seen in Table 2, nitrogen levels found in both species ranged between 0.2% and 0.6%, respectively; however, A. donax, sample PA, expressed somewhat higher content of nitrogen (1.26%). Even though these components are directly related to the nitrogen oxides emissions, values that were found in all samples show contribution to NO x much lower than from the air, which has a contribution nearly 15 or 20 times higher (García et al., 2012).
The genetic analysis indicated that COI gene sequences are useful for species discrimination within the genus Donax. The observed divergence levels (0 – 1.2%) of both morphotypes pooled (Fig. 5) are typical of intraspeciﬁc levels (Held, 2000; Hebert et al., 2003; Cardenas, Castilla & Viard, 2009). No consistent spatial structure was found in the distribution of genetic variance among geographically separated populations, suggesting extensive and ongoing gene ﬂow between geo- graphically separated populations and also between nominal D. obesulus and D. marincovichi. The same molecular marker system was highly informative when distinguishing the two Donax species included in the outgroup (D. asper and D. hanleyanus).
In the midst of a complicated large-scale task such as the A. donax program, the subsidiary task of looking for new species can be overlooked. In addition, the resources used to survey can be hard to justify when no new infestations are found, even though the increase in control costs from delayed detection can be substantial and exceed the cost of surveys (Hoshovsky and Randall 2000). While detection of new exotic species should draw on existing monitoring work, it needs to be an independent task with multiple visits every year initially and every few years in the long term. It should include vouchering and review of status. The review could be as simple as comparison with the California Exotic Pest Plant list (CalEPPC 1999). Exotic species that are not on the list should be evaluated to determine if they are recent escapes and a decision made as to whether to carry out localized control, no treatment, or full eradication.
Los parámetros de crecimiento fueron comparables con los valores obtenidos para la especie más cercana del genero Donax en condiciones similares de hábitat, lo cual sugiere que el rápido crecimiento de marucha en las playas de bahía Samanco puede estar fuertemen- te influenciado por la disponibilidad del alimento al incrementarse la productividad de las zonas costeras. Este factor es considerado de mucha importancia para obtener los índices de rendimiento, reportando para el presente estudio, un valor de Ø’= 3,10. Sin embar-
There is a lots of drugs and techniques are present to combat cancer but none of these are able to cure cancer completely. So researchers are looking for anticancer drugs from natural sources. Not only for anticancer drug, anti-microbial and anti- inflammatory compounds also discovered. Sea life is harsh, compared to terrestrial environment. Marine organisms are facing extreme condition of temperature, salinity, pressure and often anoxic and hypoxic conditions. They adopt themselves through complex biochemical and biophysical process. Donax variabilis, a bivalve mollusc from the Donacidae family, is mainly inhibit southern part of India in Bay of Bengal. The aim of this investigation is to extract a protein from different organs of D. variabilis and to determine its inhibitory effect on the proliferation of human cancer cell lines.
The impact of pH coupled to process design for the conversion of the energy crop Arundo donax to ethanol was assessed in the present study under industrially relevant solids loadings. Two main process strategies were investigated, i.e. the traditional simultaneous saccharification and co-fermentation (SSCF) and a HYBRID design, where a long high temperature enzymatic hydrolysis step was carried out prior to continued low temperature SSCF, keeping the same total reaction time. Since acetic acid was identified as the major inhibitor in the slurry, the scenarios were investigated under different fermentation pH in order to alleviate the inhibitory effect on, in particular, xylose conversion. The results show that, regardless of fermentation pH, a higher glucan conversion could be achieved with the HYBRID approach compared to SSCF. Furthermore, it was found that increasing the pH from 5.0 to 5.5 for the fermentation phase had a large positive effect on xylose consumption for both process designs, although the SSCF design was more favored. With the high sugar concentrations available at the start of fermentation during the HYBRID design, the ethanol yield was reduced in favor of cell growth and glycerol production. This finding was confirmed in shake flask fermentations where an increase in pH enhanced both glucose and xylose consumption, but also cell growth and cell yield with the overall effect being a reduced ethanol yield. In conclusion this resulted in similar overall ethanol yields at the different pH values for the HYBRID design, despite the improved xylose uptake, whereas a significant increase in overall ethanol yield was found with the SSCF design.
However, also under these conditions, the accumula- tion of 4.78 and 2.11 g/L of glucose and xylose, respec- tively, was still observed. A similar final concentration of SA (33.8 g/L) was previously obtained in fed-batch experiments on nanofiltered spent sulphite liquor with a slightly lower yield of SA on consumed sugars (0.58 g/g) and productivity (0.48 g/L h) . Overall, B. succinicip- roducens BPP7 demonstrated a significantly lower sugar consumption rate during the fed-batch phase; in fact, only feeding about 0.24 g/L h of total sugars did not lead to sugar accumulation in the medium. The different ratios of A.donax-derived to pure sugars used in FB experi- ments could not be related to the different fermentation results. It seems, however, that higher glucose:xylose ratios reduced the total acid by-product to succinic acid proportion (Table 3); these data are consistent with those reported by Pateraki and collaborators  that observed a higher total acid (TA)/SA ratio, equal to 0.65 g/g, when growing B. succiniciproducens on a semidefined medium containing 73% xylose and 11% glucose. The authors also observed increased TA/SA values (0.9–1 g/g) in spent sulphite liquor-based media, indicating that the inhibi- tors present in lignocellulosic substrates stimulate the production of other acid by-products . Although the use of lignocellulose hydrolysates as sole C source is more suitable for the development of sustainable fer- mentation processes, concentrated A. donax would also contain high concentrations of inhibitory mol- ecules such as acetic acid and phenolic compounds that were previously shown to strongly delay the growth of
The growing importance and interest of giant reed can be obviously characterized by literature databases. Based on the Google Scholar database, the total number of publications is over 17 400 (Until 12.11.2017), from which in 1 340 paper’s title contain the plant’s scientific name (Arundo donax or giant reed). Over the last 50 years, the number of publications about giant reed has been increasing, between 1997 and 2001 it almost doubled, which was typical of the later periods (Figure 1). Over the past 10 years, more than 13 000 scientific papers were published which are related to the plant, and annually, almost 100 publications appeared with giant reed or Arundo donax names in the title of publications. In those papers, the term of “biomass” and “energy” 5 600, the “biorefinery“ 1 080, the “biofuel” 2 620, the “biogas” 1 270, the “musical” 612, the “invasive” 4 040 and the “phytoremediation” 956 pieces of publication contained. It is interesting that the word "propagation" and "in vitro" same 1 560 publications can be
In the present work, the waste material Donax deltoides shells (DDS) was utilized as a heterogeneous base catalyst for biodiesel production from Calophyllum inophyllum oil (CIO)-waste cooking oil (WCO) mixture. Non-edible CIO possessing 65 mg of KOH g − 1 of acid value was mixed with WCO of low acid value in different proportions. The acid value was reduced to 33.3 mg of KOH g − 1 of oil by using a volumetric ratio of 1:1 and it was further reduced to 5.6 mg of KOH g − 1 of oil by acid catalyzed esterification process and used for biodiesel production. DDS was converted into active CaO catalyst by calcination and the catalyst characterization was performed using different instrumental techniques. The impact of calcined DDS (catalyst) concentration, reaction time and methanol to esterified oil volumetric ratio on biodiesel conversion was investigated to optimize the transesterification reaction using response surface methodology based central composite design. The biodiesel conversion was determined by proton nuclear magnetic resonance spectroscopy and a maximum biodiesel conversion of 96.5% was achieved with catalyst concentration of 7.5 wt%, methanol to oil volumetric ratio of 63.8%, reaction time of 129.3 min, stirrer speed of 450 rpm and reaction temperature of 65 °C.
Background: Solid acid catalyzed inexpensive ionic liquid (IL) pretreatment is promising because of its effectiveness at decreasing biomass recalcitrance to subsequent enzymatic hydrolysis or in situ hydrolysis of carbohydrate oligom- ers. However, the conventional strategy was limited by the complex non-isothermal process and considering only one aspect of sugar recovery. In this study, facile isothermal pretreatments using Amberlyst 35DRY catalyzed 1-n-butyl- 3-methylimidazolium chloride ([C 4 mim]Cl) at mild conditions were developed on bioenergy crop Arundo donax Linn. to enhance the combined sugars released. The physicochemical differences, enzymatic digestibility, and sugars released in situ were evaluated and compared to define the best set of conditions.
At similar process conditions, in the FT process, the fraction of solubilized biomass changed little with time (Exp. 2FT and 3FT in Table 5) even if more biomass was dissolved with respect to the closed reactor as total solubi- lized fractions of 40.3 and 44.5 % were reached after 20 and 40 min, respectively. Also in this case the higher fractions of solubilized biomass must be related to the better mass transfer regime obtained in the semi-continuous system with respect to the batch reactor. According to the initial composition of the adopted Arundo donax, it seems that substantially the whole of the hemicellulose is recovered after 20 min in the FT system, as the total yield in solubi- lized hemicellulose, estimated considering the cumulative amount of Xyl, Arab, F, Acet, FA and related oligomers, accounts for 30.4 % w/w that corresponds to a fraction of hemicellulose extraction of about 100 % (See Exp. 2FT in Table 6). Formic acid was considered to be derived from hemicellulose because the degradation of glucose from cellulose should lead to the formation of FA and Lev [38, 47] but no Lev was detected by HPLC. In this condition, lignin is also partially extracted (9.7 %), while the majority of cellulose is recalcitrant to solubilization under adopted conditions.
Abstract Shrinkage of green cane (Arundo donax L.) was measured during air-drying at room temperature. The cane began to shrink at 150% moisture content due to a remark- able collapse of parenchyma cells. The collapse recovered after boiling in water, but more serious collapse (recollapse) was induced by the following drying. On the other hand, the collapse recovered almost completely after steaming with saturated water vapor at 92°–96°C without recollapse. By comparing the thickness of cane specimens before and after steaming, the degree of cell collapse remaining in dry cane was evaluated. When the green cane was frozen prior to drying, the degree of collapse was reduced whereas the drying rate remained unchanged. The effect of prefreezing was interpreted as the generation of air bubbles in the cell lumen which hinder the effective loading of liquid tension on the cell wall. Even when the cane was carefully dried using a conventional method used by reed manufacturers, the degree of collapse was very large and it increased with elevating internode position.
fermentation in single bioreactor of steam exploded Arundo donax for lipid production using Lipomyces starkeyi as oleaginous yeast. In this work, it has been investigated the influences of environmental factors as initial pH but also inhibitory effects of organic acids, furans from hexoses decomposition and phenols from lignin decomposition, released during hydrolysis and oleaginous fermentation. Thus, this new process has two features. In one aspect, it provides an example of simultaneous utilization of carbon source which may be of general interests for microbial conversion of some organic wastes and special resources. In the other hand, it offers an opportunity to develop integrated process to reduce time and costs for microbial oil production from lignocellulosic biomasses.