Biomass Wet Weight Research Articles

Biomass estimations of cultivated kelp using underwater RGB images from a mini-ROV and computer vision approaches

Seaweed farming is the fastest-growing aquaculture sector worldwide. As farms continue to expand, automated methods for monitoring growth and biomass become increasingly important. Imaging techniques, such as Computer Vision (CV), which allow automatic object detection and segmentation can be used for rapid estimation of underwater kelp size. Here, we segmented in situ underwater RGB images of cultivated Saccharina latissima using CV techniques and explored pixel area as a tool for biomass estimations. Sampling consisted of underwater imaging of S. latissima hanging vertically from a cultivation line using a mini-ROV. In situ chlorophyll a concentrations and turbidity (proxies for phytoplankton and particle concentrations) were monitored for water visibility. We first compared manual length estimations of kelp individuals obtained from the images (through manual annotation using ImageJ software). Then, we applied CV methods to segment and calculate kelp area and investigated these measurements as a robust proxy for wet weight biomass. A strong positive linear correlation (r2 = 0.959) between length estimates from underwater image frames and manual measurements from the harvested kelp was observed. Using unsupervised learning algorithms, such as mean shift clustering, colour segmentation and adaptive thresholding from the OpenCV package in Python, kelp area was segmented and the number of individual pixels in the contour area was counted. A positive power relationship was found between length from manual measurements with CV-derived area (r2 = 0.808) estimated from underwater images. Likewise, CV-derived area had a positive power relationship with wet weight biomass (r² = 0.887). When removing data where visibility was poor due to high turbidity levels (mid-June), the power relationship was stronger between CV-derived area estimates and the field measurements (r² = 0.976 for wet weight biomass and r² = 0.979 for length). These results show that robust estimates of cultivated kelp biomass in situ are possible through kelp colour segmentation. However, we demonstrate that the quality of CV post-processing and accuracy of the model are highly dependent of environmental conditions (e.g. turbidity and chlorophyll a concentrations). The establishment of these technologies has the potential to offer scalability of production, efficient real-time monitoring of sea cultivation and improved yield predictions.

FAVIS: Fast and versatile protocol for non-destructive metabarcoding of bulk insect samples.

Insects are diverse and sustain essential ecosystem functions, yet remain understudied. Recent reports about declines in insect abundance and diversity have highlighted a pressing need for comprehensive large-scale monitoring. Metabarcoding (high-throughput bulk sequencing of marker gene amplicons) offers a cost-effective and relatively fast method for characterizing insect community samples. However, the methodology applied varies greatly among studies, thus complicating the design of large-scale and repeatable monitoring schemes. Here we describe a non-destructive metabarcoding protocol that is optimized for high-throughput processing of Malaise trap samples and other bulk insect samples. The protocol details the process from obtaining bulk samples up to submitting libraries for sequencing. It is divided into four sections: 1) Laboratory workspace preparation; 2) Sample processing-decanting ethanol, measuring the wet-weight biomass and the concentration of the preservative ethanol, performing non-destructive lysis and preserving the insect material for future work; 3) DNA extraction and purification; and 4) Library preparation and sequencing. The protocol relies on readily available reagents and materials. For steps that require expensive infrastructure, such as the DNA purification robots, we suggest alternative low-cost solutions. The use of this protocol yields a comprehensive assessment of the number of species present in a given sample, their relative read abundances and the overall insect biomass. To date, we have successfully applied the protocol to more than 7000 Malaise trap samples obtained from Sweden and Madagascar. We demonstrate the data yield from the protocol using a small subset of these samples.

Large-scale mariculture of the sponge Haliclona simulans on floating rafts in Zhao'an Bay, Fujian Province, China

Marine sponges are an important source of bioactive products and biomaterials. However, there is a bottleneck of biomass supply for sponge utilization. To overcome this bottleneck, mariculture was considered to be the most viable solution. Mariculture of the marine sponge Haliclona simulans was conducted on floating rafts in Zhao'an Bay, Fujian Province, China. The explants were suspended 0.5–2 m below the water surface to grow naturally using the mesh method. Two independent trials with different scales were performed in this study. In a small-scale trial with 30 sponge explants, with daily maintenance, the survival rate of H. simulans was 93.3% over 224 days. To determine whether harvesting twice yearly yields greater output than annual harvesting, the 30 H. simulans were randomly divided into two equivalent groups. The annual harvest group (1 harvest per year, 1PY) was harvested in 224 days, and the twice harvest groups (2 harvest per year, 2PY) were harvested at 92 days and 224 days, with approximately 30% of the biomass was retained during the first harvest to allow regrowth. The results showed that the total biomass accumulation rate was 629.27 ± 256.74% for the 1PY group and 1014.73 ± 252.56% for the 2PY group. The biomass accumulation rate of 2PY was approximately 61.26% higher than that of 1PY. To obtain more accurate yield data under industry scale, a large-scale mariculture was independently conducted with about 7500 explants and covered a sea area about 500 m2, in which each area of 0.2 m2 was occupied by a horizontal rope, and each rope held 3 vertically suspended explants. Lost or dead explants were replanted during routine maintenance. A total of 330 kg wet weight biomass was obtained from the first harvest after 92 days of cultivation, and 272 kg wet weight biomass was obtained from the second harvest after 224 days. A total of 45.05 kg dry weight sponge was obtained after drying. This finding indicates that under our mariculture methods and harvesting strategy, the yield of H. simulans can reach approximately 900 kg dry weight biomass per hectare per year. This research provides valuable data for large-scale sponge production and new methods for the industrial development of sponge products.

Use of a multi-metric macroalgal index to document severe eutrophication in a New Zealand estuary

ABSTRACT Environmental indicators that reliably describe estuary trophic response to nutrient loading are required for the effective management of New Zealand estuaries. A common estuary eutrophication response is frequent, extensive and persistent opportunistic macroalgae blooms. This study explores the utility of the Opportunistic Macroalgal Blooming Tool (OMBT) in the New River Estuary (∼4600 ha), a shallow intertidal-dominated system within a pastoral farming catchment in Southland, New Zealand. Total nitrogen (TN) loads increased from 3206 T y−1 in 2000 to 5143 T y−1 in 2020. Concomitantly, areas of opportunistic macroalgae, measured using the OMBT, expanded across the available intertidal habitat (AIH) from 34.9 ha or 1.4% of the AIH to 1383 ha or 47.6% of the AIH, and the average wet weight biomass increased from 19.3 g m−2 to a peak of 1326 g m−2 in 2019. We hypothesise that opportunistic macroalgae expanded rapidly in direct response to temporal increases in TN load, with increases disproportionately contributed by expansion and intensification of dairy farming in the catchment. This study confirmed that the OMBT predictably responded to changes in TN concentration and may therefore be useful in defining estuary-specific TN concentration thresholds to inform likely load reductions required to achieve improved environmental outcomes.

Effects of compost quality from non-dairy creamer sewage sludge-solid compost biogas-rice husk char on bok choy mustard (Brassica rapa L.)

Non-dairy creamer sewage sludge (NDCSS) has high organic matter and nutrients for compost production but NDCSS has a problem for the composting process because it has high moisture and slurry form. Therefore, the composting process of NDCSS requires mixing of other organic materials such as solid compost biogas (SCB) and rice husk char (RHC). Therefore, this study aims to determine the chemical properties of compost from a mixture combination of NDCSS, SCB, and RHC, and to assess compost quality as organic fertilizer from a mixture combination of NDCSS, SCB, and RHC through growth and yield of bok choy mustard (Brassica rapa L). Experiments were carried out in greenhouses from March to September 2019. The research treatment consisted of 7 treatments mixture combination of NDCSS, SCB, and RHC for the composting process, and each treatment was repeated 4 times. The composting process is carried out by anaerobic or fermentation methods. The research layout was used as a randomized complete block design (RCBD). The NDCSS can produce compost with the highest N content, while the RHC will produce compost with the highest P. The mixture combination of NDCSS, SCB, RHC, and the mixture combination of SCB and RC will produce compost with the highest K content. Compost from NDCSS produces the best organic fertilizer because it is able to make the best biomass wet weight and dry weight of bok choy mustard biomass.

Bioreactivity, Guttation and Agents Influencing Surface Tension of Water Emitted by Actively Growing Indoor Mould Isolates.

The secretion of metabolites in guttation droplets by indoor moulds is not well documented. This study demonstrates the guttation of metabolites by actively growing common indoor moulds. Old and fresh biomasses of indoor isolates of Aspergillus versicolor, Chaetomium globosum, Penicillium expansum, Trichoderma atroviride, T. trixiae, Rhizopus sp. and Stachybotrys sp. were compared. Metabolic activity indicated by viability staining and guttation of liquid droplets detected in young (<3 weeks old) biomass were absent in old (>6 months old) cultures consisting of dehydrated hyphae and dormant conidia. Fresh (<3 weeks old) biomasses were toxic more than 10 times towards mammalian cell lines (PK-15 and MNA) compared to the old dormant, dry biomasses, when calculated per biomass wet weight and per conidial particle. Surfactant activity was emitted in exudates from fresh biomass of T. atroviride, Rhizopus sp. and Stachybotrys sp. Surfactant activity was also provoked by fresh conidia from T. atroviride and Stachybotrys sp. strains. Water repealing substances were emitted by cultures of P. expansum, T. atroviride and C. globosum strains. The metabolic state of the indoor fungal growth may influence emission of liquid soluble bioreactive metabolites into the indoor air.

Mapping and Analysis of Biomass Supply Chains in Andalusia and the Republic of Ireland

The bioeconomy can play a critical role in helping countries to find alternative sustainable sources of products and energy. Countries with diverse terrestrial and marine ecosystems will see diverging feedstock opportunities to develop these new value chains. Understanding the sources, composition, and regional availability of these biomass feedstocks is an essential first step in developing new sustainable bio-based value chains. In this paper, an assessment and analysis of regional biomass availability was conducted in the diverse regions of Andalusia and Ireland using a bioresource mapping model. The model provides regional stakeholders with a first glance at the regional opportunities with regards to feedstock availability and an estimate of the transportation costs associated with moving the feedstock to a different modelled location/region for the envisioned biorefinery plant. The analysis found that there were more than 30 million tonnes of (wet weight) biomass arisings from Ireland (84,000 km2) with only around 4.8 million tonnes from the Andalusian region (87,000 km2). The study found that Cork in Ireland stood out as the main contributor of biomass feedstock in the Irish region, with animal manures making the largest contribution. Meanwhile, the areas of Almería, Jaén, and Córdoba were the main contributors of biomass in the Andalusia region, with olive residues identified as the most abundant biomass resource. This analysis also found that, while considerable feedstock divergence existed within the regions, the mapping model could act as an effective tool for collecting and interpreting the regional data on a transnational basis.

Hydrodynamic characteristics of a full-scale kelp model for aquaculture applications

Hydrodynamic characteristics are needed to optimize the design of kelp aquaculture systems. To support this need, the objective of this study was to resolve both the normal and tangential drag forces acting on a dense aggregate of kelp blades using full-scale physical model tests. The physical model was designed to match the exposed length, individual blade flexural rigidity, the number of blades per unit width, the mass/length of biomass, and the aggregate mass density of kelp cultured at the University of New England experimental aquaculture lease site in Saco Bay, Maine USA. Tow tests were conducted at the United States Naval Academy in a tank with the dimensions of 116m × 7.9m × 4.9 m. The large tank size enabled the use of the full-scale physical model, minimizing dynamic similarity issues. In a series of tests, the model was towed in orientations both aligned and perpendicular to the tow direction. Horizontal and vertical reaction forces were measured for five tow speeds, along with the deflection of the dense kelp aggregate. With these datasets and the wet weight biomass per length of the model, normal and tangential drag forces were calculated. Drag components were processed into corresponding normal and tangential drag-area values. The drag-area representation was chosen since reference areas were ambiguous for both the actual kelp and model. At the higher speeds, the total horizontal drag in the aligned configuration were slightly lower than for the perpendicular orientation. Normal drag-areas as a function of tow speed ranged from 2.36 m2/m to 1.39 m2/m for the aligned case and from 2.49 to 1.88 m2/m for the perpendicular case. Tangential drag-areas as a function of tow speed ranged from 0.264 m2/m to 0.0325 m2/m for the aligned case and from 0.213 to 0.0415 m2/m for the perpendicular case. A transition from a bluff body to a streamlined body occurred as the tow speeds increased. To investigate this transition, horizontal components of the normal and tangential drag forces were reconstructed with the results of the tow tests. The reconstructed forces were obtained using a force balance system of equations with drag-area values for tow speeds less than 0.25 m/s extrapolated from the experimental datasets. For both aligned and perpendicular orientations, the model-aggregate reconfigured at a threshold of 0.25 m/s. We defined the threshold for reconfiguration as the tow speed at which the horizontal component of tangential drag equaled or exceeded the horizontal component of the normal drag. The drag-area results from this study can be incorporated into a dynamic fluid-structure interaction model representing kelp aggregates as a finite element beam prescribed with in-situ values of length, volume, mass density and flexural-rigidity of kelp material.

Growing Media Combination Improve Plant Growth and Results of Eggplant (Solanum melongena L) in Hydroponic Culture Duck Bucked System

Today business eggplant still give a pretty good market opportunities, especially to meet the demand of the domestic market. Hydroponics is a way of cultivating plants without using soil, but the use of media such as rice husk, sawdust, fine sand, bricks, coco, and more.The research objective, to get the best medium composition hydroponic cultivation of eggplant Duck Bucked system. Research conducted at the Laboratory of Urban Agriculture Faculty of Agriculture, University of Muhammadiyah Jember, December 2018 to April 2019, indesigned randomized block design factorial arranged secaranon repeated 3 times. that is A (Charcoal chaff), S (Sawdust), B (Bricks), AS ( Charcoal and Sawdust Husk) with 3: 1, AB (Charcoal Husk and Bricks) with 3: 1, BA (Bricks and Charcoal husks with 3:1, BS (Bricks and Sawdust) with 3:1, SA (Sawdust and Charcoal husks) with 3:1, SB (Sawdust and bricks) with 3:1), ASB (Charcoal Sawdust Husk and Bricks) with 1:1:1. The result showed treatment of growing media composition of the substrate affects the vegetative growth of plant height at 45 and 60 days after planting, biomass wet weight, dry weight biomass, root fresh weight and root dry weight, the best substrate media broken bricks. While composition of the substrate growing media influence on the amount of fruit harvest and to all III-V substrate media best media substrate broken bricks. Conclusions broken bricks media substrate is a substrate of the best media for eggplant plants in the hydroponic system Duck Bucked.

Solid-state fermentation of sterile slurry and palm kernel cake (PKC) mixture using Rhizopus azygosporus UICC 539

This study described solid-state fermentation of sterile slurry and palm kernel cake (PKC) mixtures by Rhizopus azygosporus UICC 539, preparation of the fungus and waste mixture as a formula for animal feed, and analysis of nutrient content of the formula. Preparation of inoculum (v/v) in Potato Sucrose Broth (PSB) was carried out at 30 and 40 °C for 5 days. Wet weight biomass was used as inoculum for solid-state fermentation (SSF) using sterile slurry and PKC (3:1) mixtures and SSF was carried out in flat trays (20×20×5 cm) at 30 and 40 °C for 5 days. The fermented waste mixture was dried at 60 °C for 5 days. Changes in nutrient content of the formula were observed by comparing the treatment and control. Formula prepared at 30 °C showed an increase in carbohydrate, protein and moisture content. A decrease was observed in total fat and ash content, calorie from fat and total calorie. Formula prepared at 40 °C showed an increase in protein and ash content. A decrease was observed in carbohydrate, moisture and total fat content, calorie from fat, and total calorie. Rhizopus azygosporus UICC 539 was able to grow and utilize the palm oil processing waste and improved the nutrient content of the formula.

Solid-state fermentation and formulation of non-sterile palm oil processing waste using Rhizopus azygosporus UICC 539

This study reported the ability of Rhizopus azygosporus UICC 539 to utilize non-sterile slurry and palm kernel cake (PKC) through solid-state fermentation, preparation of the fungus and non-sterile waste mixture as a formula for animal feed, and analysis of nutrient content of the formula. Fungal culture in PSB at 30 and 40 °C for 5 days was prepared and wet weight biomass was used as inoculum for animal feed formula. Solid-state fermentation (SSF) was carried out on the mixtures of non-sterile slurry and PKC (3:1) at 30 and 40 °C for 5 days and the fermented waste mixtures were dried at 60°C for 5 days. The results showed that during SSF there were presence of colonies of other fungi and bacteria from the waste mixture besides R. azygosporus. The total cell number of R. azygosporus and other fungi were decreased after SSF. Changes in nutrient content in the formula were observed by comparing the treatment and control. Formula prepared at 40 °C showed an increase of carbohydrate content and total calorie, while formula prepared at 30 °C showed an increase only at carbohydrate content. A decrease of protein, water content, ash content, total fat, and energy from fat, was observed in formulas prepared at both temperatures.

Enhancement of l-amino acid oxidase production by Bacillus subtilis HLZ-68 with oxygen-vector and asymmetric degradation of dl-arginine to d-arginine

Bacillus subtilis HLZ-68 can produce l-amino acid oxidase (l-AAO), and dl-arginine can be degraded asymmetrically by suspending the wet bacterial biomass in the degradation liquid. By adding oxygen-vectors to the fermentation medium, the collected amount of wet bacterial biomass can be increased. Taking n-dodecane, n-hexadecane, oleic acid, paraffin and n-hexane as oxygen-vectors, the optimal oxygen-vector was 1.2% (v/v) oleic acid. The wet weight biomass increased by 66.83% and the activity of l-AAO in the fermentation broth increased by 38.88% compared with those before the addition of oxygen-vector. The standard sample dl-arginine was derivatized by phenyl isothiocyanate, and then subjected to high-performance liquid chromatography (HPLC), and the obtained peak area and arginine content were used as standard curves to measure the dl-arginine. The content of d-arginine and l-arginine in the initial degradation solution was 50% each, and the bacterial cells were added to the initial degradation solution of dl-arginine. After 21 h of reaction, l-arginine was completely degraded, leaving 47% of d-arginine. d-alanine was easily extracted from the reaction solution using cation-exchange resin, after centrifugation, decolourization, concentration and vacuum drying, and the chemical and optical purity of the extracted d-arginine were 92.68% and 97.46%, respectively.

Fishery-independent observations of Atlantic menhaden abundance in the coastal waters south of New York

Atlantic menhaden (Brevoortia tyrannus) is a migratory forage fish whose geographic range extends from the Gulf of Maine to Florida. Despite the ecological and commercial importance of menhaden, few fishery-independent surveys have been conducted to quantify their distributions of abundance and biomass. Active acoustic surveys of menhaden schools were conducted using 38, 120, and 200 kHz scientific echosounders in two regions on the continental shelf south of Long Island, New York during the summer of 2014 and spring, summer, and fall of 2015. Spatial distributions of menhaden schools were considered to be clustered across all surveys where three or more schools were observed. Estimates of school volume were highly variable, ranging from 30 to 48,000 m3. Menhaden aggregations were absent in the spring (April, May, and June) and present in the summer and fall (July, August, and September) surveys. Target strength measurements at 120 kHz during the summer and fall surveys were consistent with predicted values for adult Atlantic menhaden, suggesting that fish size did not change substantially during this time. Peak menhaden abundance was observed during August 2015 (approximately 157,000 fish km−2 with a wet weight biomass density of 35,000 kg km−2). Multifrequency acoustic surveys can provide an efficient and fishery-independent method for quantifying menhaden abundance and distribution in coastal habitats.

Habitat Heterogeneity and Spatio-Temporal Distribution of Macrobenthos in in a Tropical Estuarine Mangrove Ecosystem

This paper deals with spatio-temporal distribution of macrobenthos and their relationship with physico-chemical environment and sediment properties in estuarine mangrove ecosystem of Chorao, Goa. The complex mangrove habitats provide nutrient and play vital role in the establishment of healthy mangrove fauna. The mangrove of Chorao is inhabited by 14 species of mangrove and associated flora in different substrata. The macrofaunal density in the four study stations varied significantly. Total numerical count was 7960 at C1, 3300 at C2, 6705 at C3 and 7075 at C4. The wet weight biomass was 27.18 at C1, 17. 62 at C2, 15.85 at C3 and 24.30 at C4. There was strong seasonality in the occurrence of fauna in the study area. The average macrofaunaltaxa was dominated by polychaeta (55%), crustacea (26%) and mollusca (14%). The other groups like nematode, echiurida and nemertenea was insignificant. The epibenthic feeding forms of polychaetes and scavengers/browsers of crustacean were more common in the sandy substratum, while deposit feeders were common in muddy substratum at Chorao mangrove. The result of the present study suggests that mangrove ecosystem with different substrata and physico-chemical parameters supports varied fauna and had different effect on the benthic community.

Effect of sucrose on biofilm formed in situ on titanium material.

Because sucrose may change the composition of biofilms formed on dental surfaces, the aim of this study was to evaluate in situ the effect of this dietary sugar on biofilm formation on titanium surface. In this blind, crossover, in situ study, 10 volunteers wore, in 3 phases of 7days each, a palatal appliance containing titanium specimens. In each phase, the specimens were treated extraorally with 20% sucrose solution at a frequency of 4 or 8times per day. As control, no treatment was rendered (0×). At the end of each phase, the biofilms were collected for biochemical analysis of biofilm wet weight (biomass), protein concentration, soluble (S-EPS), and insoluble (I-EPS) extracellular polysaccharides and intracellular polysaccharides (IPS), and for microbiologic analysis by checkerboard DNA-DNA hybridization (for levels and proportions of 40 bacterial species). Biochemical data were analyzed by linear regression and microbiological findings by Friedman and Dunn tests (α= .05). A positive significant linear relationship was found among sucrose exposure (0×, 4×, and 8×) and biomass, S-EPS, I-EPS and IPS (p< 0.05). The biofilms treated with sucrose (4× and/or 8×) presented higher mean total levels of the 40 bacterial species evaluated, higher proportions of red complex species and lower proportions of the host-compatible green complex species, in comparison with the control group (p< 0.05). The findings of the present study suggest that daily sucrose exposure has a harmful effect on the composition of biofilms formed on titanium surfaces.

THE DISTRIBUTION AND SOME ECOLOGICAL ASPECTS OF MARINE ALGAL GENUS EUCHEUMA IN THE INDONESIAN WATERS

Eight species of Eucheuma ait found to grow in the Indonesian waters making the amount of species of Eucheuma which had been found become 17 species. A certain species specifically found only in certain areas. Those species are usually found at the depths of 30 to 150 cm during low tide at the reef flat, moat and algal ridge of the coral reefs where temperatures and salinities varied from 29° to 31° and from 30 to 34‰ respectivelly. There are various habitats of Eucheuma i.e. dead and live corals, limestones, sand and shells. Average wet weight biomass of Eucheuma species at the areas investigated varied from 2 to 552 g/m . The highest value is that of Eucheuma spinosum found in East Seram (Maluku), and the lowest is that of E. cottonii found in the Keifing Island, East Seram. The species of Eucheuma commonly found in association with Acanthopora, Gracilaria and Halimeda. ABSTRAK

Effects of an invasive polychaete on benthic phosphorus cycling at sea basin scale: An ecosystem disservice.

Macrofaunal activities in sediments modify nutrient fluxes in different ways including the expression of species-specific functional traits and density-dependent population processes. The invasive polychaete genus Marenzelleria was first observed in the Baltic Sea in the 1980s. It has caused changes in benthic processes and affected the functioning of ecosystem services such as nutrient regulation. The large-scale effects of these changes are not known. We estimated the current Marenzelleria spp. wet weight biomass in the Baltic Sea to be 60-87kton (95% confidence interval). We assessed the potential impact of Marenzelleria spp. on phosphorus cycling using a spatially explicit model, comparing estimates of expected sediment to water phosphorus fluxes from a biophysical model to ecologically relevant experimental measurements of benthic phosphorus flux. The estimated yearly net increases (95% CI) in phosphorous flux due to Marenzelleria spp. were 4.2-6.1kton based on the biophysical model and 6.3-9.1kton based on experimental data. The current biomass densities of Marenzelleria spp. in the Baltic Sea enhance the phosphorus fluxes from sediment to water on a sea basin scale. Although high densities of Marenzelleria spp. can increase phosphorus retention locally, such biomass densities are uncommon. Thus, the major effect of Marenzelleria seems to be a large-scale net decrease in the self-cleaning capacity of the Baltic Sea that counteracts human efforts to mitigate eutrophication in the region.

Use of the KlADH3 promoter for the quantitative production of the murine PDE5A isoforms in the yeast Kluyveromyces lactis

BackgroundPhosphodiesterases (PDE) are a superfamily of enzymes that hydrolyse cyclic nucleotides (cAMP/cGMP), signal molecules in transduction pathways regulating crucial aspects of cell life. PDEs regulate the intensity and duration of the cyclic nucleotides signal modulating the downstream biological effect. Due to this critical role associated with the extensive distribution and multiplicity of isozymes, the 11 mammalian families (PDE1 to PDE11) constitute key therapeutic targets. PDE5, one of these cGMP-specific hydrolysing families, is the molecular target of several well known drugs used to treat erectile dysfunction and pulmonary hypertension. Kluyveromyces lactis, one of the few yeasts capable of utilizing lactose, is an attractive host alternative to Saccharomyces cerevisiae for heterologous protein production. Here we established K. lactis as a powerful host for the quantitative production of the murine PDE5 isoforms.ResultsUsing the promoter of the highly expressed KlADH3 gene, multicopy plasmids were engineered to produce the native and recombinant Mus musculus PDE5 in K. lactis. Yeast cells produced large amounts of the purified A1, A2 and A3 isoforms displaying Km, Vmax and Sildenafil inhibition values similar to those of the native murine enzymes. PDE5 whose yield was nearly 1 mg/g wet weight biomass for all three isozymes (30 mg/L culture), is well tolerated by K. lactis cells without major growth deficiencies and interferences with the endogenous cAMP/cGMP signal transduction pathways.ConclusionsTo our knowledge, this is the first time that the entire PDE5 isozymes family containing both regulatory and catalytic domains has been produced at high levels in a heterologous eukaryotic organism. K. lactis has been shown to be a very promising host platform for large scale production of mammalian PDEs for biochemical and structural studies and for the development of new specific PDE inhibitors for therapeutic applications in many pathologies.

Using unmanned aerial vehicles (UAVs) to measure jellyfish aggregations

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 591:29-36 (2018) - DOI: https://doi.org/10.3354/meps12414 NOTE Using unmanned aerial vehicles (UAVs) to measure jellyfish aggregations Jessica Schaub1,*, Brian P. V. Hunt1,2,3, Evgeny A. Pakhomov1,2,3, Keith Holmes3, Yuhao Lu4, Lucy Quayle3 1Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada 2Institute of the Oceans and Fisheries, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada 3Hakai Institute, PO Box 309, Heriot Bay, British Columbia V0P 1H0, Canada 4Integrated Remote Sensing Studio, Forest Sciences Center, 2424 Main Mall, Vancouver, British Columbia V6K 1Z4, Canada *Corresponding author: jessica.schaub@alumni.ubc.caAdvance View was available online January 29, 2018 ABSTRACT: Unmanned aerial vehicles (UAVs, or drones) are becoming increasingly common as tools to perform high-resolution but broad-scale measurements of habitats and populations simultaneously. In this study, we tested the application of UAVs to aerial surveys of jellyfish and their suitability for measuring and monitoring aggregations. We paired net hauls with linear image transects taken by a UAV to measure 5 Aurelia spp. aggregations over the course of 1 d in Pruth Bay, British Columbia, Canada. Georeferenced image transects were processed to determine aggregation areal extent and estimate percent cover of jellyfish. The percent cover estimates and net haul density data were highly comparable for all aggregations. Using combined UAV-derived surface area estimates and net haul biomass estimates, we calculated that jellyfish aggregation size ranged from 65 to 117 t wet weight biomass. We discuss the potential for additional UAV-based measurements including jellyfish abundance and individual size. The study demonstrates the potential of UAVs as powerful tools for characterizing and researching jellyfish aggregations in situ. KEY WORDS: Drones · Jellyfish aggregations · GIS · Unmanned aerial vehicles Full text in pdf format Supplementary material PreviousNextCite this article as: Schaub J, Hunt BPV, Pakhomov EA, Holmes K, Lu Y, Quayle L (2018) Using unmanned aerial vehicles (UAVs) to measure jellyfish aggregations. Mar Ecol Prog Ser 591:29-36. https://doi.org/10.3354/meps12414 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 591. Online publication date: March 19, 2018 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2018 Inter-Research.

Naturally occurring phytopathogens enhance biological control of water hyacinth (Eichhornia crassipes) by Megamelus scutellaris (Hemiptera: Delphacidae), even in eutrophic water

Insect biological control agents directly damage target weeds by removal of plant biomass, but herbivorous insects have both direct and indirect impacts on their host plants and can also facilitate pathogen infection. Megamelus scutellaris Berg (Hemiptera: Delphacidae) was recently released into South Africa to help control invasive water hyacinth (Eichhornia crassipes, Pontederiaceae). We compared the impact of fungicide surface-sterilised and unsterilised M. scutellaris individuals and water hyacinth leaves on growth of the weed at two nutrient levels. The survival and reproduction of adult M. scutellaris was not reduced by sterilisation. Under high nutrient conditions, unsterilised M. scutellaris with unsterilised leaves reduced water hyacinth daughter plant production by 32%, length of the second petiole by 15%, chlorophyll content by 27% and wet weight biomass by 48%, while also increasing leaf chlorosis 17-fold, in relation to control plants under the same nutrient regime. Surface sterilisation of the insect and/or plant surfaces led to a general reduction in these impacts on water hyacinth growth and health. This contrast was less evident under low nutrient conditions. Megamelus scutellaris facilitated infection by fungal and other pathogens, thus its biology is compatible with pathogens that could be developed into mycoherbicides. This integrated approach may be ideal for management of infestations of water hyacinth in eutrophic water systems where control has been problematic, both in South Africa and elsewhere.