Winter Samples Research Articles

Muscle, season, sex, and carcass weight affected pork texture, collagen characteristics, and intramuscular fat content.

In this study, pigs from 3 supply chains were slaughtered in an Australian summer and winter (n = 20 for each supply chain). The pigs were from 2 sexes (female and castrated male) and 2 carcass weight groups (high: 95.0 to 100.0kg and low: 75.0 to 80.0kg). From each carcass, the Biceps femoris (BF), Longissimus thoracis et lumborum (LTL), and Triceps brachii (TB) were excised at 24h postmortem, vacuum packed, frozen at 24-48h and transported to the lab. Cooking loss, Warner-Bratzler shear force (WBSF) and texture profile analysis (adhesiveness, chewiness, cohesiveness, hardness, resilience, and springiness) were measured in LTL and BF. pH, collagen content, and solubility and intramuscular fat (IMF) content were determined for all muscles. Results showed that BF was tougher than LTL, and winter samples were tougher than summer ones (P < 0.05). The TB had higher pH, collagen, and IMF content than BF and LTL (P < 0.05). Collagen solubility was higher in castrated male and winter samples. pH, collagen solubility, and IMF content were significantly (P < 0.05) related to chewiness and hardness in pork BF and LTL. pH and IMF were also related to cooking loss, while collagen solubility and IMF were related to WBSF (P < 0.05). The relationships of pH and IMF with pork texture were predominantly driven by the LTL, while the relationships between collagen solubility and texture were predominantly driven by the BF. Collagen solubility and IMF of pork BF and TB were related to those of LTL, but the correlations were not strong enough for prediction. Pork texture and chemical components were affected by muscle, seasons, sex and carcass weight. pH, collagen solubility, and IMF-affected pork texture.

Isolation and characterization of tannin-degrading bacteria from the rumen of wild Hokkaido sika deer (Cervus nippon yezoensis).

We isolated tannin-degrading bacteria from the rumen of wild Hokkaido sika deer and characterized their phylogeny and tannase activity in relation to sample sources. The condensed tannin level was higher in all deer rumen samples (n = 20) than in forage-fed cattle rumen samples (n = 6), whereas no hydrolyzable tannins were detected in any of the rumen samples. Rumen bacteria were enumerated on nonselective brain heart infusion (BHI) agar medium and then transferred onto tannic acid-containing BHI agar plates to screen for bacteria only showing growth (tannin-resistant bacteria) and those showing both growth and a clear zone (tannin-degrading bacteria). Summer samples provided only tannin-resistant bacteria, none of which showed tannin-degrading activity. Although winter samples also provided tannin-resistant bacteria, most isolates exhibited tannin-degrading activity. A total of 70 isolates exhibiting tannin-degrading activity were classified as Streptococcus bovis group based on 16S rRNA gene sequencing and further classified into two groups, either group A or group B. Group A consisted of isolates showing weak tannase activity, whereas group B included a majority of the isolates exhibiting high tannase activity. These results suggest that wild Hokkaido sika deer develop tannin-degrading Streptococcus in the rumen during winter, which allows access to woody food materials rich in tannins.

ҚАЗАҚСТАН РЕСПУБЛИКАСЫ СОЛТҮСТІК ӨҢІРІНІҢ ЖОҒАРҒЫ ТОБЫЛ ЖӘНЕ ҚАРАТОМАР СУ ҚОЙМАЛАРЫНЫҢ СУЛАРЫНДАҒЫ АУЫР МЕТАЛДАРДЫҢ ҚҰРАМЫН КЕШЕНДІ БАҒАЛАУ

The article presents the results of comprehensive studies on the water quality of the Verkhnetobolsky and Karatomarsky reservoirs in Kazakhstan, focusing on heavy metals. Legal and regulatory documents on state environmental control of Kazakhstan waters were reviewed, along with normative documents and scientific recommendations on water quality and toxicology, including hygienic and MPC standards. State, interstate, and international requirements for water sampling and physico-chemical analysis were studied, including winter sampling methods under ice cover. Concentrations of metals and heavy elements were determined, and heavy metal indicators comply with hygienic safety standards for household, drinking, and cultural and general use. According to the Unified Classification System, the water quality for manganese and cadmium places the reservoirs in the fourth quality class, suitable only for irrigation and industrial use, requiring extensive treatment for household use. The Tobol River is generally classified as polluted. Most metals show small standard deviation and variation coefficients, indicating reservoir homogeneity. However, manganese, cadmium, zinc, copper, boron, and lead show high deviations, suggesting significant content differences due to element mobility and runoff from fields and tributaries. The results serve as reference information and methodological recommendations for assessing heavy metals and elements in freshwater reservoirs in temperate zones.

Effects of seasonal variation on phytochemicals contributing to the antimalarial and antitrypanosomal activities of Breonadia salicina using a metabolomic approach

This study involves the investigation of various plant parts of Breonadia salicina (Vahl) Hepper and J.R.I. Wood across multiple consecutive seasons. It aims to delve into the phytochemistry of these different plant parts and establish connections between the findings and their biological activities. This comprehensive approach employs metabolomics techniques, with the ultimate goal of exploring the potential for drug development. Samples were collected in Fondwe, a village in Limpopo (South Africa), based on local reports of the efficacy of this plant used by traditional healers in the area. The antimalarial and antitrypanosomal activities of samples collected over the seasons were determined with the parasite lactate dehydrogenase (pLDH) and specific Trypanosoma brucei assays, respectively. Consequently, a total of 24 compounds were tentatively identified through ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). Chemical profiles of the different plant parts of Breonadia salicina collected in different seasons produced contrasting metabolic profiles. Chemometric analysis of the UPLC-QTOF-MS data enabled us to determine the chemical variability of the crude stem bark, root and leaf extracts (n = 48) collected over four consecutive seasons by evaluating the metabolomics fingerprinting of the samples using an untargeted approach. Principal component analysis (PCA), hierarchical cluster analysis (HCA), and partial least squares discriminant analysis (PLS-DA) indicated the existence of two key clusters that are linked to the root, stem bark, and leaves. The stem and root chemistry differed from that of the leaves. Seasonal variations were noted in each plant part, with autumn and winter samples closely grouped compared to spring and summer samples in the methanol leaf extracts. Biochemometric analysis could not relate specific compounds to the antimalarial and antitrypanosomal activities of the active extracts, underscoring the intricate interactions among the secondary metabolites. This study further confirms the optimal plant parts to collect in each season for the most effective antimalarial and antitrypanosomal activities.

Validity of winter sampling for estimation of salmonid abundance by electrofishing

Electrofishing removal sampling is a common method for abundance estimation of juvenile salmonids in streams and is usually performed during autumn. European guidelines specify that sampling should be conducted at water temperatures ≥ 5 °C, but studies investigating the validity of sampling below this threshold are lacking. We conducted electrofishing experiments during autumn and winter in three Norwegian rivers, comparing abundance estimation accuracy, rate of fish emigration from electrofishing sites, and mortality for juvenile Atlantic salmon Salmo salar and brown trout Salmo trutta. Abundance estimates were significantly more accurate during autumn than during winter, less accurate for age-0 fish than for older parr, and more accurate when the number of electrofishing passes was increased. By digging through the substrate after electrofishing, we found that a higher proportion of fish were uncatchable during winter than during autumn, and that age-0 fish were more likely than older fish to be uncatchable. For salmon older than age-0, both autumn and winter sampling consistently yielded relatively accurate abundance estimates. However, the rate of fish emigration from electrofishing sites was significantly higher during autumn than during winter and if block nets are not used, emigration during autumn sampling could cause severe underestimation of Atlantic salmon abundance. Fish mortality did not differ between autumn and winter sampling and was low for both species and all age groups. We recommend the use of block nets and conducting five electrofishing passes to reduce the likelihood of severe estimation error.

Seasonal and taxa impact on edible sea cucumber metabolome as analyzed via a multiplex approach of mass spectroscopy-based metabolomics

Sea cucumbers, belonging to class Holothuroidea, are marine invertebrates with substantial bioactive compounds and nutritive value. This study presents a multiplex metabolomics approach to dissect between winter and summer samples of two Red Sea cucumbers: Holothuria atra and Actinopyga crassa. LC-MS and GC-MS followed by multivariate data analyses were employed for metabolites profiling and seasonal biomarkers assignment for each species. A total of 314 metabolites were annotated in both species belonging to amino acids, sugars, sugar alcohols, acids, triacylglycerides (TAGs), phospholipids, lyso-phospholipids, sphingolipids, phosphatidylcholines, diacylglycerols, different glycolipids, and others, adding to the nutritive value of sea cucumber. GC-MS analysis revealed for amino acids i.e., alanine as the main polar primary metabolite class in sea cucumbers. LC-MS analysis targeting non-polar metabolites revealed TAGs as the main class followed by phospholipids and lyso-phospholipids. Multivariate orthogonal partial least square discriminant analysis (OPLS-DA) revealed that A. crassa is enriched in alanine and lactic acid than H. atra versus higher levels of pyroglutamic acid and ethanolamine and TAGs in the later. Summer A. crassa was distinguished from its winter specimen by its higher TAGs, glycine and glycerol levels versus enrichment of winter samples in lyso-phospholipids, isoleucine, and proline. Such metabolomic study revealed for A. crassa and H. atra richness in nutrient metabolites, alongside collection season effect on their amino acids and lipids profiles.

IMPACT OF WET GLUTEN CONTENT ON NON-LINEAR VISCOELASTIC PROPERTIES OF WHEAT FLOUR DOUGHS

The impact of wet gluten content in wheat flours on viscoelastic responses of the resulting wheat flour doughs under large deformations were studied using the Large Amplitude Oscillatory Shear (LAOS) tests. For this purpose, dough samples of hard red winter (HRW) wheat flour with 29.80.26% wet gluten and soft red winter (SRW) wheat flour with 23.90.15% wet gluten were obtained at the end of the Farinograph tests. Farinograph mixing stability and optimum water absorption capacity were higher for HRW wheat flour. LAOS tests revealed the contribution of gluten content to the resilience of wheat flour dough against the increasing deformations. Higher strain stiffening was found for HRW wheat flour dough with higher gluten content under large deformations with high frequency, resembling the deformations experienced during dough processing steps such as mixing or sheeting. Intracycle shear thinning behaviors of doughs were not affected by the gluten content at each frequency studied.

Changes of putative pathogenic species within the water bacterial community in large-scale drinking water treatment and distribution systems

Although the management of microbes in drinking water is of paramount importance for public health, there remain challenges in comprehensively examining pathogenic bacteria in the water supply system at the species level. In this study, high-throughput sequencing of nearly full-length 16S rRNA genes was performed to investigate the changes of the water bacterial community in three large-scale drinking water treatment plants (DWTPs) and their corresponding distribution systems during winter and summer. Our findings revealed significant differences in the bacterial community structure between winter and summer water samples for each DWTP and its distribution management area (DMA). In the groundwater-fed DWTP, selective enrichment of mycobacterial species was observed in both seasons, and the subsequent DMA also exhibited strong selection for specific mycobacterial species. In one of the surface water-fed DWTPs, certain Legionella species present in the source water in winter were selectively enriched in the bacterial community after pre-oxidation, although they were susceptible to the subsequent purification steps. A variety of putative pathogenic species (n = 83) were identified based on our pathogen identification pipeline, with the dominant species representing opportunistic pathogens commonly found in water supply systems. While pathogen removal primarily occurred during the purification processes of DWTPs, especially for surface water-fed plants, the relative abundance of pathogenic bacteria in the DMA water flora was lower than that in the DWTP effluent flora, indicating a diminished competitiveness of pathogens within the DMA ecosystem.

Shrubification and snow removal have an antagonistic effect on the accumulation of rhizosphere organic carbon components in peatlands

A warming climate will cause shrubification and less winter snow cover in peatlands, which are an important global carbon sink. Both shrubification and snowpack reduction affect organic carbon sequestration, yet their effects on the dynamics of microbial necromass carbon (MNC) and plant necromass carbon (PNC) in rhizosphere soil are indeterminate. This investigation focuses on the effects of shrubification and snow cover changes on organic carbon components and their mechanisms in rhizosphere soil. For this purpose, a field in situ experiment on snow cover removal and natural snow cover was conducted in shrub and herb peatlands, respectively, in winter, and rhizosphere soil samples were collected in the following growing season. The MNC biomarker amino sugar and the PNC biomarker lignin phenol were quantified, and in addition to the general soil physical, chemical, and biological parameters, root exudates were measured based on untargeted metabolomics. The findings showed that MNC contributes more to SOC in spring, with the majority of it derived from fungal necromass carbon, and the contribution of PNC to SOC gradually increased in later seasons, with a consequent decrease in rhizosphere SOC stability. Shrubification decreased the MNC content by 15.80% and the PNC content by 7.68%, whereas snow removal increased the MNC content by 8.24% and 2.58% and the PNC content by 11.31% and 17.39% in shrub and herb peatlands, respectively. The changes in root exudates may be an important factor regulating the accumulation of different SOC components. Specifically, sugars and amino acids had a positive priming effect on MNC and PNC, whereas organic acids had a negative priming effect. The mechanisms by which root exudates mediated MNC and PNC accumulation differed depending on the season. This research will be useful in forecasting future changes in carbon sink function and providing a theoretical foundation for increasing carbon sink measures.

Prediction of dissolved organic nitrogen via spectroscopic fingerprint in the shallow riverbed sediments of effluent-dominated rivers: A case study in Xi’an, northwest China

An evaluation on the impacts of effluent discharge to receiving rivers is in demand. Discharged dissolved organic nitrogen (DON) with high eutrophication potentials tends to accumulate in the shallow riverbed sediments especially for effluent-dominated rivers. Since DON characterization requires for advanced analytical tools, there is thereby a need but it is still a challenge to evaluate their distribution and transformation in the riverbed sediments. Considering the fact that DON is an important part of dissolved organic matter (DOM), which has plentiful spectral information, the authors hypothesize if it is feasible to predict DON variations in riverbed sediments via the DOM properties in surface water or sediment porewater? Here, the spatiotemporal spectral characteristics of DOM in river water and sediment porewater of two effluent-dominated rivers were investigated. Compared to surface water, more abundant relationships among fluorephores and spectra-derived parameters in porewater were observed. The relatively high DON contents in both surface water (0.16–0.47 mg-N/L) and sediment porewater (0.35–5.02 mg-N/L) compared to those reported in other natural waters highlighted the importance in predicting DON in effluent-dominated rivers. The DON in the oxic zone from winter samples carried more humus-like signals, while the fractions in summer samples recognized protein-like and humus-like signals. Two machine learning methods, i.e., random forest (RF) and extreme gradient boosting (XGBoost) were employed to provide evidence-based information on how DON contents and properties differed at variable depths. RF (R2: 0.920, 0.475) outperformed XGBoost (R2: 0.488, 0.316) in predicting DON in winter-oxic zone and winter-suboxic zone. While XGboot (R2: 0.515, 0.787) is superior than RF (R2: 0.317, 0.567) in summer-oxic zone and summer-suboxic zone. Fluorophore of C1 served as the most important variable for predicting DON in winter samples in both models. SUVA260 and SUVA280 were verified most impressive predictor for samples from suboxic zone in summer in both models. HIX represented the most important variable predicting DON in summer samples in XGBoost model. These findings are critical for understanding the transformation processes of DON in the shallow riverbed sediments in receiving rivers, and could provide important implications to improve wastewater discharge management and river health.

Detection rates of pesticide residues in Saudi Arabian produce as influenced by season

Pesticide residues and persistent organic pollutants (POPs) are known hazardous chemicals that exhibits bioaccumulation in organisms and the ecosystem in general. There is limited evidence on the levels of these contaminants among common Saudi crops grown as well as the effects of season on their levels. Hence, the present investigated the levels of pesticide residues in major fruit and vegetable crops collected during the winter and summer seasons in Saudi Arabia (SA). A total of 392 samples taken from 28 locally produced vegetables and fruits were purchased from local markets in Riyadh, SA during peak summer (N = 263) (June-August 2022) and peak winter (N = 129) (December-February 2022). Food samples were extracted and cleaned up using the modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) technique. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) and gas chromatography–tandem mass spectrometry (GC–MS/MS) instruments were used to determine pesticide residues. Crops that had the highest percentage exceeding the maximum residue limit (MRL) include pepper (7.9 %) as well as apricot, fig and pomegranates (3.1 %). Cypermethrin was the most prevalent pesticide residue in both winter and summer samples with detection rates of 13.2 % and 14.1 % respectively (p = 0.33). Thiamethoxam detection rates was significantly higher in winter (7.8 %) than summer (3.0 %) (p = 0.04). There is a high detection rate of pesticide residues in SA independent of season, with cypermethrin being the most common. Thiamethoxam is more commonly detected in winter than summer crops. The study should be extended to include other potential sources of pesticide residues such as fishes grown in aqua farms and other poultry products.

Molecular compositions and sources of organic aerosols at a rural site on the Guanzhong Plain, Northwest China: The importance of biomass burning

The concentration of PM2.5 has considerably reduced in recent years, but remains relatively high in China. In particular, the increasing contribution of organic compounds to PM2.5 generates popular pressure for further reductions, resulting in an urgent need to study organic aerosol (OA). To investigate the molecular composition and source contribution of OA in the rural area of the Guanzhong Plain, Northwest China, PM2.5 samples were collected during 3–23 August 2016 and 5–20 January 2017 and studied for more than 100 organic tracer compounds. The mean concentration of total measured organic compounds is 662 ± 296 ng/m3 in summer and 3258 ± 1925 ng/m3 in winter. Levoglucosan is the most abundant single compound found throughout the sampling period, which is a crucial tracer for biomass burning emissions, preliminary suggesting that biomass burning is an essential source of OA. In summer, organic compounds such as lipid compounds, sugar compounds, and polycyclic aromatic hydrocarbons (PAHs), more come from higher plants, wood burning, vehicle exhausts, plastic waste, and other direct emission sources. Oxygenated PAHs (OPAHs), nitrophenols, and phthalic acids more come from the atmosphere through the oxidation reaction of aromatic precursors, especially photochemical oxidation. However, in winter, most of the increases in concentrations of organic compounds are attributed to biomass burning. The analysis of a haze event (14–19 January 2017) during the winter sampling period shows that the increases in the concentration of organic compounds are unaccompanied by strong secondary formation under lower relative humidity (49.1% ± 13.5%). The main reason for the growth of OA in this haze event is the accumulation of primary OA (POA). The source apportionment by the positive matrix factorization (PMF) model shows that biomass burning (37.1%) is the primary source of OA in the rural regions of the Guanzhong Plain, especially in winter (40.6%). The contribution of secondary formation decreases from 26.0% in summer to 16.9% in winter, and the contribution of fossil fuel emissions is comparable across both seasons.

Determination of hematobiochemical and fore stomach fluid constituents of llama (Lama glama) living in Egypt

There are no available data regarding the hematology, serum biochemistry, and fore stomach fluid constituents of llama (Lama glama) in Egypt. This study aimed to establish normal reference values for blood and fore stomach fluid constituents of llama and determine the influence of sex and season on these parameters under Egyptian conditions. The study was performed on (n = 38; 22 female, 16 male; 1–7 years) apparently healthy llamas located in the Giza Zoo and private zoo in the Ismailia Governorate. Samples were collected in two seasons and divided into summer and winter samples. Differences in the mean and range values of packed cell volume, serum minerals, fore stomach fluid pH, and total protozoal count in Egypt were recorded. Sex and season had minimal effects on hematology and only erythrocyte count showed a significant (p < 0.05) increase in males compared with females. Regarding serum biochemistry, males showed significant (p < 0.05) increases in alanine transaminase and calcium levels, while globulin significantly (p < 0.05) increased in females. The influence of season on serum biochemistry was evident in alanine transaminase, total protein, albumin, and chloride which increased significantly (p < 0.05) in summer, while urea, bilirubin, and magnesium increased significantly (p < 0.05) in winter. Fore stomach fluid pH and ammonia showed significant (p < 0.05) increases in winter, while the total protozoal count increased significantly (p < 0.05) in summer and in males compared with females. The results obtained in this study can serve as reference values for the hematobiochemical and fore stomach fluid constituents of llama in Egypt.

Transcriptome Analysis of Gill Tissues from Neptunea cumingii in Different Seasons

Neptunea cumingii is an economically important marine shellfish found in the Yellow and Bohai Seas areas of China. In this study, samples of Neptunea cumingii were collected in Zhangzidao and Yantai during spring, summer, autumn, and winter to clarify the gene expression patterns and regulatory mechanisms in their gills in different seasons. Transcriptome analysis was conducted using Neptunea cumingii gill tissues, and genes with significantly different expression levels were extracted for functional verification. The most genes with differences in expression (DEGs) were found in comparisons of the winter and summer samples. Gene enrichment analysis based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes terms showed that these DEGs were mainly involved in immune and metabolic pathways, and they had significant effects on oxidative stress, body metabolism, and protein synthesis in Neptunea cumingii. Further screening of DEGs identified thirty-four genes related to temperature regulation, comprising thirteen genes with roles in innate immunity in shellfish, twelve genes related to oxidative stress, and nine genes related to protein synthesis and energy metabolism. Eleven DEGs were randomly selected for qPCR verification, and the results were consistent with the transcriptome analysis results. In summary, the transcriptome results differed significantly between seasons in the gill tissues of Neptunea cumingii. The expression levels of immune regulatory genes could be promoted in Neptunea cumingii during the high temperature season, whereas the expression of these genes may be inhibited in the low temperature season. The results obtained in this study provide insights into the molecular defense mechanisms that might allow Neptunea cumingii to adapt to climate change.

Long-read sequencing reveals the shell microbiome of apparently healthy American lobsters Homarus americanus from Atlantic Canada.

The shell microbial community of lobsters-a key factor in the development of epizootic shell disease (ESD)-is still insufficiently researched in Atlantic Canada and many knowledge gaps remain. This study aimed to establish a baseline description and analysis of the shell microbiome of apparently healthy lobsters from four locations in the region. More than 180 lobster shell swab samples were collected from New Brunswick, Nova Scotia and Prince Edward Island (PEI). PacBio long-read 16S rDNA sequencing and bioinformatic analyses in QIIME2 identified the shell-associated bacteria. The shell microbiome of healthy lobsters consisted mainly of the bacterial classes Gammaproteobacteria, Saprospiria, Verrucomicrobiae, Alphaproteobacteria, Flavobacteriia, Acidimicrobiia and Planctomycetia. The microbial composition differed regionally and seasonally, with some classes showing decreased or increased relative abundances in the PEI samples as well as in the winter and spring samples in Nova Scotia. The core shell microbiome included potentially pathogenic as well as beneficial bacterial taxa, of which some were present only in certain regions. Bacterial taxa that have previously been associated with ESD were present on healthy lobsters in Atlantic Canada, but their frequency differed by location, sampling time, and moult stage. This study indicated that geographical and seasonal factors influenced the shell microbiome of apparently healthy lobsters more than host factors such as sex, size, and moult stage. Our results provide valuable reference microbial data from lobsters in a disease-free state.

Metabolomic analysis and bioactivities of Arbutus unedo leaves harvested across the seasons in different natural habitats of Sardinia (Italy)

BackgroundArbutus unedo L. is a wild tree of Mediterranean regions used as food and in traditional medicine and important for afforestation programs. There is no detailed information available on the variation of A. unedo leaves metabolome across the seasons. The leaves were analyzed by Proton nuclear magnetic resonance (1 H NMR)-based metabolomics, comparing samples harvested across the seasons and in ten different natural habitats of Sardinia (Italy).ResultsMultivariate analysis showed the impact of seasonal variation on the metabolome: glucose and quinic acid increased in summer, while in spring sucrose was accumulated. β-Arbutin, the main known active principle of A. unedo, generally reached the highest concentration in autumn. In winter, O-β-methylglucose, γ-aminobutyric acid (GABA), flavonols (quercetin-3-O-α-rhamnoside, myricetin-3-O-α-rhamnoside, kaempferol-3-O-α-rhamnoside), catechin, and gallocatechin increased. Characteristic metabolomic features were found also for samples collected in different locations. For instance, trees growing at the highest altitude and exposed to lower temperatures produced less flavonols and catechins. The only sample collected on trees growing on limestones, dolomites, and dolomitic limestones type of soil showed generally the highest content of arbutin. The highest phenolics content was found during spring, while samples collected on flowering branches in winter were the ones with the highest flavonoid content. The antioxidant activity was also variated, ranging from 1.3 to 10.1 mg of Trolox equivalents (TE)/mL of extract, and it was positively correlated to both total phenolics and flavonoid content. Winter samples showed the lowest antibacterial activity, while summer and autumn ones exhibited the highest activity (IC50 values ranging from 17.3 to 42.3 µg/mL against Staphylococcal species).ConclusionThis work provides 1 H-NMR fingerprinting of A. unedo leaves, elucidating the main metabolites and their variations during seasons. On the basis of arbutin content, autumn could be considered the balsamic period of this taxon. Samples collected in this season were also the most active ones as antibacterial. Moreover, an interesting metabolomic profile enriched in catechins and flavonols was observed in leaves collected in winter on flowering branches which were endowed with high antioxidant potential.

In hot water: Interactions of temperature, nitrogen form and availability and photosynthetic and nitrogen uptake responses in natural Karenia brevis populations

During 2020–2021, an unusually prolonged bloom of the toxigenic dinoflagellate Karenia brevis persisted for more than 12 months along the Gulf coast of Florida, resulting in severe environmental effects. Motivated by the possibility that unusual nutrient conditions existed during summer 2021, the short-term interactions of temperature, nitrogen (N) forms (ammonium (NH4+), nitrate (NO3−), and urea) and availability on photosynthesis-irradiance responses and N uptake rates were examined in summer 2021 and compared to such responses from the earlier winter. Winter samples were exposed to temperatures of 15, 20, 25, 30 °C while summer samples were incubated at 15, 25, 30, 33 °C, representing the maximum range the cells might experience throughout the water column due to daytime surface heating or extreme weather events. Depending on thermal history of the cells, photosynthetic performance differed when cells were exposed to the same temperature, showing a capacity for thermal acclimation in this species. Although blooms generally do not persist throughout the summer, bloom biomass was remarkably higher in summer than during the winter. However, most of the photosynthetic parameters and N uptake rates, as well as total carbon (C) and N cell−1 were significantly lower in the summer populations, showing that the summer populations were photosynthetically and nutritionally stressed. When the summer cells were treated with urea, however, uptake rates and total C and N cell−1 were higher than with the other N substrates, especially in warmer waters, showing differential thermal responses depending on N forms.

Effect of Biofloc Technology Enriches the Growth of Litopenaeus vannamei (Boone, 1931).

The use of probiotics in shrimp farms has expanded as an alternative to antibiotics, improving shrimp health, growth, disease control and water quality. However, the efficacy of probiotics in intensive systems using biofloc remains uncertain. This study investigated bioremediation and biocontrol of commercial probiotics using biofloc, analysing water quality and bacterial groups influencing shrimp performance. Thirteen microbial colonies were observed in the biofloc samples, and their evolutionary history was inferred using the neighbour-joining method. Analysis using MEGA6 software revealed 99.6% similarity between colony 1P1 and Virgibacillus sp. and 99.8% similarity between colony 2P2 and Bacillus kochii. The study analysed the biochemical and amino acid content of shrimp cultured using biofloc technology for 85days. The study found that biofloc-cultured L. Vannamei flesh had higher levels of moisture (31%), ash (15.2%), protein (34%) and lipid (12.6%). No seasonal variations were observed between biofloc samples in winter and summer seasons. Protein levels were found to be appropriate for shrimp growth in both ex situ and in situ biofloc systems. The average growth rate (kg/m2) of biofloc-cultured shrimp was significantly greater than in normal pond shrimp in both samples. The feed conversion ratio in the biofloc tank was lower than in the usual pond-cultured shrimp, possibly due to lower growth rate, lower feeding frequency (2 times per day) and higher density. The growth of L. vannamei shrimp is influenced by stocking density, with higher stocking density affecting the average weight. The study also examined the growth biochemical and amino acid content of shrimp cultured using biofloc technology.

Temporal Assessment of Crop Protection Agents in Water Bodies of Haryana Districts

Background: The study was conducted to quantify the presence of crop protection agents in 233 water samples collected from water bodies situated in cities of Panipat, Karnal, Rohtak, Sonipat and Hisar districts of Haryana, India. Water samples were collected during different seasons the year for the period from 2014-2018. Methods: The samples were processed by liquid- liquid partitioning method and quantified by Gas Chromatography and Mass Spectrometry. The water samples were screened for 55 pesticides. Result: Estimation of the residues revealed that 23.5 and 6.6% of pesticides were detected in 68 and 165 monsoon and winter samples, respectively. Chlorpyrifos, pretilachlor, butachlor and lambda cyhalothrin were predominantly present in all the water samples analyzed. Chorpyrifos detected in water samples from Karnal were above standard limit prescribed by EPA 8081and8141 but some samples were below UAS Health advisory life time value.

Variations in the dairy wastewater properties and bacterial diversity of each unit in membrane-enclosed anaerobic lagoon treatment process in Heilongjiang Province

In order to meet the land use requirements of the treated wastewater from high density polyethylene (HDPE) membrane-enclosed anaerobic lagoons, the physical and chemical properties of the wastewater in an HDPE membrane-enclosed anaerobic lagoon were measured. The total nitrogen content (TN) in wastewater treated in membrane-enclosed anaerobic lagoons is 3165 and 1510 mg/L in winter and summer respectively. The wastewater can be used as liquid organic fertilizer, partly replacing chemical fertilizer. The safety dosage of the wastewater was 21.48 t/ha for rice and 9.54 t/ha for corn, respectively. Meanwhile, the wastewater has the characteristics of high salt (conductivity>16.0 mS/cm) and high organic matter content (COD>16,900 mg/kg). Therefore, the potential negative effects of the wastewater on soil salinity and pH should be assessed. 16S rRNA was used to investigate the bacterial population structure and assess potential biological risks of land use of the wastewater. The wastewater from lagoon has the least and the most bacterial abundance in summer and winter, respectively. The bacterial diversity of wastewater samples from lagoon is the most. 21 and 24 phyla were detected in winter and summer samples respectively. Clostridium is the absolute dominant bacteria in the summer water samples and the absolute dominant bacteria is Trichococcus in winter water samples. Several animal and plant bacterial pathogens such as Campylobacter, Corynebacterium, Facklamia and Erysipelothrix can be detected in the wastewater samples. More than 70% of pathogenic bacteria such as Campylobacter, Facklamia, Erysipelothrix and Acholeplasma can be removed by lagoon in summer, but only about 99% of Corynebacterium is still in the lagoon (XYH). While more than 60% of Corynebacterium, Facklamia and Erysipelothrix are not removed in winter. So the biological risk of land use of anaerobic pond wastewater needs to be considered.