High Nutrient Levels Research Articles

Summer Distributional Characteristics of Surface Phytoplankton Related with Multiple Environmental Variables in the Korean Coastal Waters

Multiple environmental variables related to ocean currents, freshwater runoff, and upwelling in a coastal area have complex effects on the phytoplankton community. To assess the influence of environmental variables on the phytoplankton community structure during the summer of 2019, we investigated the various abiotic and biotic factors in Korean coastal waters (KCWs), separated into five different zones. Summer environmental factors in KCWs were strongly influenced by Changjiang Diluted Water (CDW) in St. SO (Southern Offshore) 1 and 2, upwelling in St. SI (Southern Inshore) 2–4, and Nakdong River discharge in St. SI 12. In particular, low–salinity water masses (p < 0.05 for nearby locations) of CDW gradually expanded from the East China Sea to southwestern KCWs from June to July. In addition, there were high levels of nutrients following freshwater runoff from the Nakdong River in southeastern KCW, which led to the dominance of Cryptomonas spp. (81%), a freshwater and brackish water algae. On the other hand, upwelling areas in southwestern KCW were dominated by diatoms Skeletonema spp., and are characterized by high phosphate concentrations (p < 0.05) and low temperatures (p < 0.05) compared to nearby locations. Leptocylindrus danicus (20%) was dominant due to the effect of water temperature in the SE (Southeastern area) zone. Low nutrient concentrations were maintained in the East Sea (dissolved inorganic nitrogen (DIN) = 0.39 ± 0.40 μM; dissolved inorganic phosphate (DIP) = 0.09 ± 0.03 μM) and the Yellow Sea (DIN = 0.40 ± 0.07 μM; DIP = 0.04 ± 0.02 μM), which were characterized by low levels of chlorophyll a and dominated by unidentified small flagellates (35, 40%). Therefore, our results indicated that hydro–oceanographic events such as upwelling and freshwater run–off, but not ocean currents, provide nutrients to the euphotic layers of the coastal environment and play important roles in determining the phytoplankton community structure during summer in the KCWs.

The Punta de la Mona Rhodolith Bed: Shallow-Water Mediterranean Rhodoliths (Almuñecar, Granada, Southern Spain)

Shallow-water rhodolith beds are rare in the Mediterranean Sea and generally poorly known. The Punta de la Mona rhodolith bed extends for 16,000 square meters in shallow and oligotrophic waters at the southern coast of Spain, off Almuñecar in the Alborán Sea. We present a detailed analysis of the structure (rhodolith cover and density, rhodolith size and shape, sediment granulometry) and morphospecies composition of the bed along a depth gradient. A stratified sampling was carried out at six depths (9, 12, 15, 18, 21, and 24 m), estimating rhodolith cover and abundance; rhodoliths were collected from one 30 by 30 cm quadrat for each transect, resulting in 18 samples and a total of 656 rhodoliths. The collected rhodoliths were measured and the coralline algal components identified morphoanatomically through a stereomicroscope and SEM. Sediment on the seafloor mainly consisted of pebbles and cobbles; the highest rhodolith cover occurred between 15 and 18 m, and the lowest at the shallowest and deepest transects (9 and 24 m). Mean Rhodolith size was similar throughout the depth range (23–35 mm) with a slight increase at 24 m, although the largest rhodoliths occurred at 21 m. In monospecific rhodoliths, size depended more on the forming species than on depth. We found 25 non-geniculate coralline morphospecies, nearly all rhodolith-forming morphospecies reported in the Mediterranean Sea in recent accounts. The highest morphospecies richness (18–19) and proportional abundance were found at intermediate depths (15–18 m), where rhodolith cover is also highest. Lithophyllum incrustans and Lithophyllum dentatum dominated at shallow depths (9–12 m), whereas Lithothamnion valens was the dominant species at intermediate and greater depths. Overall, the latter species was the most common in the rhodolith bed. The shallow-water rhodolith bed in Punta de la Mona is probably the most diverse in the Mediterranean Sea. This highlights the importance of the conservation of this habitat and, in general, emphasizes the role of the Alborán Sea as a diversity center of coralline algae. The Punta de la Mona example contradicts the common assumption in the geological literature that rhodolith beds are indicative of oligophotic environments with high nutrients levels.

Nutrients dynamics in water and sediment of the Bonny Estuary, Niger Delta, Nigeria.

Surface water and sediment from Bonny Estuary, Nigeria, were assessed to determine the nutrient dynamics. Nutrients (nitrates, phosphates, and total organic carbon (TOC)) and some physicochemical parameters of water samples are collected from three sampling stations along the Bonny Estuary during wet seasons (April 2017, 2018, and 2019) and dry seasons (November 2017, 2018, and 2019). Physicochemical parameters analyses were conducted in situ using Horiba water checker (Model U-10). Surface water nitrate and phosphate were analysed by APHA 4500-NO3-B Colorimetric method, while sediment nitrates and phosphate by Chemical Analysis for Ecological Matter CAEM/APHA 4500-NO3-E Colorimetric method and TOC by CAEM-Wet-Oxidation Titration method. There was no significant seasonal variation in pH, temperature, dissolved oxygen, biological oxygen demand, conductivity, and turbidity nor across the sampling stations. TDS values showed significant seasonal variation with higher values in the wet seasons. Surface water nitrate and phosphate had higher concentrations in wet seasonsthough within recommended limits. Conversely, nitrate, phosphate, and TOC in the sediments were quite high, with higher values in wet seasons, especially the downstream of the estuary. The high levels of nutrients in the sediments as opposed to surface water could be a result of rapid deposition of nutrients which could lead to possible nutrient enrichment of the sediment. Nutrient levels in the sediment have increased fourfold over the study period. This suggests an influx of nutrients into the estuary, due to human activities. Nutrient enrichment could result in deterioration in aquatic water quality and pose a threat to the ecology of the estuary.

Morphological, chemoprofile and soil analysis comparison of Corymbia citriodora (Hook.) K.D. Hill and L.A.S. Johnson along with the green synthesis of iron oxide nanoparticles

ObjectiveThe objective of this research study was to identify the morphological characteristics and essential oil components of Corymbia citriodora (Hook.) K. D. Hill and L.A.S. Johnson grown in two different geographical locations-Kodaikanal and Nashik. A comparative soil analysis was also carried out to detect the soil quality under Corymbia citriodora (C. citriodora) plantation. Green synthesis of Iron oxide nanoparticles from C. citriodora leaf extract has been carried out. MethodsHydro-distillation method was used to extract the essential oils from both the species and GC–MS analysis was carried out to detect the chemical components. A comparative morphological analysis was carried out for both the plant specimens while soil analysis from three different places- forest soil, soil under C. citriodora plantation and agricultural field soil was performed. Iron oxide nanoparticles were synthesized by using leaf extract of C. citrodora and its reduction by FeSO4·7H2O solution was found. The structural properties of Iron oxide nanoparticles were studied by UV, X-ray diffraction, FTIR and SEM. ResultsThe morphological result showed that both the C. citriodora species had the same characteristics with a slight variation in the bark and leaf colour. The essential oil profile showed citronellol as the major compound in both the species, dI- Isopulegol was found only in C. citriodora from Kodaikanal in more concentration (less than citronellol) while the eucalyptol content was found to be more in Nashik species. For soil analysis it was observed that, even though the soil in the C. citriodora area is more acidic than forest soil, with lower quantities of organic matter and minerals, it also has high levels of organic matter and nutrients, as well as low pH when compared to the soil in agricultural field. The characterisation of iron oxide nanoparticles by UV, FTIR, XRD and SEM confirmed its formation. ConclusionsThe two varieties of C. citriodora from two different locations have not shown wide differences in their morphological characters. The amount of essential oil was observed to be low in Nashik when compared to Kodaikanal, which is due to the geographical area difference. These results showed that the essential oil content varies depending on location, as well as the fact that C. citriodora has little or no negative effects on soil quality. The green method used for synthesis of iron oxide nanoparticles was found to be effective.

An Integrated Approach for Water Quality Modelling of Soan River Using HEC-RAS

Abstract Water quality modeling has been shown to be a useful tool in strategic water quality management. In this study, HEC-RAS model was employed to assess the water quality of Soan River. The model was calibrated and validated successfully by evaluation through NSE and R2 values. The simulated BOD and DO values were found to be in agreement with the measured values. Furthermore, the findings revealed that the Soan River was polluted downstream of the Kaak Bridge due to industrialization and urbanization along the River’s banks. The HEC-RAS model is a useful tool for managing water quality and making decisions. Furthermore, many situations were investigated in order to provide appropriate options for River water quality management. Sewage effluents, agricultural runoff and industrial effluents were found to be responsible for the high nutrient levels in the River which in turn reduced DO levels and increased BOD. The requirement for comprehensive integrated models that can be used to make defensible decisions is now important for the long-term management of aquatic ecosystems. The uncertainty surrounding the outcomes of integrated modelling studies makes it difficult for water resource managers to execute them.

Scenedesmus sp. Harvesting by Using Natural Coagulant after Phycoremediation of Heavy Metals in Different Concentrations of Wet Market Wastewater for Potential Fish Feeds

The high level of organic elements and nutrients in wet market wastewater (WMW) has raised public concerns. The phycoremediation method, which utilizes microalgae, can be further valorized by converting it into various valuable potential bioproducts. The production of Scenedesmus sp. in WMW was investigated as an ingredient for fish feeds in this study. The potential of two natural plant-based coagulants, Cajanus cajan (pigeon pea) and Cicer arietinum (chickpea), for harvesting microalgae Scenedesmus sp. were compared. Statistical analysis and response surface methodology were used to investigate the flocculant dosage and pH effect on harvesting efficiency. It was found that Cajanus cajan (CC) and Cicer arietinum (CA) both had a harvesting efficiency of 89.29% and 88.56%, respectively. The optimal dosage and pH for CC were 178.75 mg/L and 11.72, and for CA, they were 137.77 mg/L and 9.15. This study indicated that Scenedesmus sp. can remove heavy metals cadmium (87.24%), chromium (85.55%), and ferum (90.35%), respectively. The level of heavy metals content (μg/kg in ppb) in dry biomass was found ultimately low and did not exceed the maximum concentration set up by the European Commission Regulation. The Fourier Transform Infrared (FTIR) analysis of microalgae biomass displayed O-H, N-H and C-H functional groups. The protein–lipid for the potential application as fish feed in the sample was 45.8–43.6% and 15–13%. Moreover, the biomass contained 53% to 40% oleic acid, which is high concentration of fatty acid methyl ester (FAME). As a result, there is high potential of Scenedesmus sp. in wastewater treatment; both natural coagulants give the possibilities for efficient microalgae biomass recovery as fish feed and are applicable for improving the quality of Scenedesmus sp. cultivated in WMW.

Analysis of Metabolomic Changes in Xylem and Phloem Sap of Cucumber under Phosphorus Stresses

Cucumber xylem and phloem sap is a key link in nutrient distribution, transportation and signal transduction of cucumber plants; however, the metabolic response mechanism of cucumber xylem and phloem sap under phosphorus stress has not been clearly revealed. In this study, gas chromatography-mass spectrometry (GC-MS) combined with principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used to analyze the metabolites in cucumber xylem and phloem sap under different phosphorus stress. A total of 22 differential metabolites were screened from xylem and phloem sap, respectively. Through the analysis of metabolic pathways of differential metabolites, four and three key metabolic pathways were screened, respectively. The results showed that compared with the normal phosphorus level, the content of most amino acids in the key metabolic pathway increased in xylem but decreased in phloem both under low and high phosphorus stress levels. The contents of sucrose and glucose in phloem glycolysis pathway showed a positive correlation with the change of phosphorus nutrient levels. The tricarboxylic acid cycle was promoted in xylem and phloem of cucumber under low and high phosphorus nutrient levels, and the contents of malic acid and citric acid increased significantly. This study provided abundant biochemical information for the metabolic response and regulation strategies of cucumber xylem and phloem under phosphorus stress, and is committed to looking for more sensitive markers to evaluate the supply level of phosphorus nutrients in cucumber.

Scale-dependent effects of vegetation on flow velocity and biogeochemical conditions in aquatic systems

In rivers, scale-dependent feedbacks resulting from physical habitat modifications control the lateral expansion of submerged plant patches, while the mechanisms that limit patch expansion on a longitudinal dimension remain unknown. Our objective was to investigate the effects of patch length on physical habitat modification (i.e., flow velocity, sediment grain size distribution), the consequences for biogeochemical conditions (i.e., accumulation/depletion of nutrients, microbial respiration), and for individual plants (i.e., shoot length). We measured all of these parameters along natural patches of increasing length. These measurements were performed at two sites that differed in mean flow velocity, sediment grain size, and trophic level. The results showed a significant effect of patch length on organic matter content and nutrient concentrations in interstitial water. For the shortest patches sampled, all of these parameters had similar values to those measured at the upstream control position. For longer patches, organic matter content and orthophosphate and ammonium concentrations increased within the patch compared to the upstream bare sediment, whereas nitrate concentrations decreased, suggesting changes in vertical water exchanges and an increase in anaerobic microbial activities. Furthermore, plant height was related to patch length by a quadratic pattern, probably due reduced hydrodynamic stress occurring for increasing patch length, combined with conditions that are less favourable for plants over a threshold length, possibly due to the light limitation or to the high concentration of ammonium that in the concentration range we measured may be toxic for plants. The threshold lengths over which patches influence the nutrient concentrations were reduced for the site with higher nutrient levels. We demonstrated that the plant-induced modifications of the physical habitat exert important effects on biogeochemical conditions, with possible consequences for patch dynamics and ecosystem functioning.

Effect of Warning Labels on Consumer Motivation and Intention to Avoid Consuming Processed Foods.

Nutritional warnings (NWs) as a front-of-package label were implemented as a public policy aiding consumers with recognizing processed foods with high levels of critical nutrients (sodium, saturated fats, carbohydrates, and calories). However, in spite of this tool being well positioned in consumer decision making, there is little extant knowledge about the relationship between the message sent by NW, nutritional knowledge, consumer motivation, and the intention to avoid consuming processed foods. To understand these dimensions’ relations, a theoretical model was created and subsequently tested through structural equations. We applied a survey to 807 home food purchasing decision makers. The results show that the direct effect of NW messages raises the intention to avoid processed foods, while eating motivation is negative in its direct effect on the same avoidance intention. However, the message sent by NWs had a mediating effect between the intentions to avoid processed food and eating motivation but showed no such effect on nutritional knowledge. This suggests that the message sent by NWs was able to turn negative eating motivation into positive eating motivation to avoid processed foods. In conclusion, NWs help mitigate eating motivations, as well as boost the intention to avoid processed foods.

Perspective from 2021 Eggs during Pregnancy and Lactation and Beyond: What have we learned in the past 5 years?

In the 5 years since our article ‘Cracking the egg potential during pregnancy and lactation’ was published, the recognition that eggs likely provide critical nutrients during pregnancy and lactation for newborn and child health and neurodevelopment, and also that they can contribute to reducing poverty and supporting sustainable food systems has continued to grow. Eggs are rich in choline and docosahexaenoic acid (DHA), two nutrients hypothesized to have favorable effects on birth outcomes as well as on child growth, morbidity, inflammation, and neurodevelopment. They contain high levels of several other nutrients and vitamins, including lutein and other carotenoids, and vitamins E, D, and B12, and folate; they are also rich in selenium and iodine. In as much as pregnant and lactating women have higher protein and other nutrient requirements compared with nonpregnant women, eggs are an ideal food to consume during this time. Nonetheless, because they are expensive relative to other sources of energy, consumption is low among women.

Investigation of the potential of native wetland plants for removal of nutrients from synthetic stormwater and domestic wastewater

Constructed floating wetlands (CFWs) promote the growth of plants in buoyant structures where nutrients can be assimilated into biomass, and thus offer an alternative treatment that is potentially more economically viable than conventional constructed wetlands (CWs). This study examined the hydroponic growth of native Australian plants including Baumea rubiginosa (BR) and Phragmites australis (PA) in a synthetic water mix representing both stormwater and municipal waste water, and their total nitrogen (TN) and total phosphorus (TP) uptake rate over a 35-week period. With increases in the nutrient levels in synthetic waters, the overall dry weight of both roots and shoots, and the accumulated TN and TP values removed from the system, all increased. For both storm and waste waters, BR was found to have a higher overall shoot weight compared to that for the PA. In waters with relatively high nutrient levels, BR was found to have a lower overall root weight compared to that for the PA. The %TN accumulated in all plant root tissue was found to be greater than the shoot tissue and consequently the TN removal efficacy by PA (species with a relatively high growth rate of roots) was high in comparison to that by BR (species with a relatively high growth rate of shoots). The TP removal efficacy by BR was higher than that of PA. These results show that CFWs with native plant species could be used to reduce the nutrients levels in both stormwater and wastewater under a Mediterranean climate condition.

Relating Invasibility and Invasiveness: Case Study of Impatiens parviflora

Data on alien species show that plant invasions are caused by a complex combination of characteristics of invasive species (invasiveness) and characteristics of invaded environment (invasibility).Impatiens parviflorais one of Europe’s top invasive species. The present study aimed to evaluate molecular diversity of populations of highly invasive in LithuaniaI. parvifloraby applying several DNA markers and relating genetic parameters to abiotic and biotic environment. For sampling, urban forests, riparian forests, and agrarian shrublands were selected. Three different DNA-based techniques, Simple Sequence Repeats (SSR), Inter Simple Sequence Repeat (ISSR) markers, and Random Amplified Polymorphic DNA (RAPD), were used for detecting genetic variation between 21 populations. All population individuals were monomorphic and homozygotic for four loci and heterozygotic for one locus by SSR analysis. Hierarchical analyses of molecular variance at ISSR and RAPD loci revealed significant differentiation of populations depending on geographic zones of the country. Bayesian Structure analyses of molecular data demonstrated existence of many genetic clusters and this finding is in support to multiple introduction of the species. The polymorphism extent at ISSR loci was positively correlated with the total coverage of herbaceous plant species. The coverage byI. parviflorawas negatively correlated with the total number of herbaceous species and light in the sites. Our results indicate that Lithuanian sites withI. parvifloramight be distinguished by high soil nutrient levels. According to the principal component analysis, the coverage byI. parviflorawas a more important variable of populations compared to molecular data or parameters of abiotic environment. In conclusion, complexity of invasibility and invasiveness factors determine the variability ofI. parviflorasites, including genetic traits, coverage of invasive species and conditions of environment that were significant and interrelated.

INNOVATION FOR MANUFACTURING FERTILIZER FROM COFFEE LEATHER WASTE FOR THE COMMUNITY AND FARMER GROUP IN BONDOWOSO

The coffee husk waste has not been utilized optimally by farmers. Coffee skin waste, which has been considered as a leftover material from the production of ground coffee, turns out to have many benefits and uses in life. Based on the results of research by experts, coffee husk waste is useful in agriculture, animal husbandry and fisheries, namely as compost, protein nutrition and additional fiber in animal feed. This solid waste of coffee rind has high levels of organic matter and nutrients that can improve soil structure. One of the efforts that can be done to handle the increasing amount of coffee husk waste is by processing coffee skin waste into compost. The by-products in the form of coffee skins range from 50-60 percent of the harvest. If the yield is 1000 kg of fresh coffee, then about 400-500 kg of coffee beans will be produced and the rest is a by-product in the form of coffee husks. The advantage of this coffee skin compost is that its nitrogen content is quite high, around 6% so that it can substitute for fertilizers containing nitrogen. The problem is that the C/N ratio is high enough that it takes a long time to decompose or the solution is to add nitrogen sources and a decomposer to speed up decomposition. This community service activity was carried out in collaboration with the community in the Bondowoso district, namely the KAPAS Community in Sumbergading Village, Sumberwringin District and the TSS community in Sukosari Lor Village, Sukosari District. In the Bondowoso area, there are many youth communities with various activities aimed at advancing people's lives and improving the socio-economic status of the area. Coffee husk waste is very common in the area, so far, coffee skin waste has not been used optimally, so its benefits cannot be obtained. The solutions offered in this community service activity include: Provide an understanding of the importance of utilizing existing coffee husk waste for communities and communities in the Bondowoso area, Provide training on making fertilizer from coffee husk waste as an innovation in making fertilizer to increase agricultural yields in the Bondowoso area, Exploring and empowering the natural potential that exists in the community environment so that it can be put to good use, Initiate the business of making fertilizer from coffee husk waste as an innovation in making fertilizer for cost efficiency in agriculture Keywords : waste, coffee husk, innovation, fertilizer, health DAFTAR PUSTAKA Dzung NA., Dzung TT.,Khanh VTP.,2013. Evaluation of Coffe Husk Compost for Improving Soil Fertility and Sustainable Coffee Production in Rural Central Highland of Vietnam. Resources and Environment, 3(4), 77-82 Abdoellah, S dan A.Wardani. 1993. Impact of Cocoa Development on Marginal Land to Farmers Income: A Case in Gunung Kidul Regency, Indonesia. Pelita Perkebunan, 9(3), 97 – 104 Bressani, R.1979. The by-products of coffee berries.dalam coffee pulp: composition, technology, and utilization. Editor J. E. Braham and R. Bressani. Ottawa: Institute of Nutrition of Central America and Panama. Berlian, Z., Syarifah, dan Sari DS., 2015. Pengaruh Pemberian Limbah Kulit Kopi (Coffea robusta L.) terhadap Pertumbuhan Cabai Keriting (Capsicum annum L.). Jurnal Biota, 1(1), 22-32. Sahputra, A., Barus A., dan Sipayung R., 2013. Pertumbuhan dan produksi bawang merah (Allium ascalonicum L.) terhadap pemberian kompos kulit kopi dan pupuk organik cair. Jurnal Online Agroekoteknologi, 2(1), 26-35. Maruli, A. 2010. Limbah kopi antar mahasiswa ke jerman. http://www.antaranews.com/berita/2 27334/limbah-kopi-antarmahasiswake jerman/2017.07.18. Afrizon, 2015. Potensi Kopi Sebagai bahan Baku Pupuk Kompos Di Propinsi Bengkulu. AGRITEPA, 2(1). 1, 21-32 Novita E., Fathurrohman A., Pradana HA.,2018. Pemanfaatan Kompos Blok Limbah Kulit Kopi sebagai Media Tanam. Jurnal Agrotek, 2(2), 61- 72 Muryanto, 2004 Muryanto. (2004). Potensi Limbah Kulit Kopi Sebagai Pakan Ternak. Jurnal Lokakarya, 1, 112-114. Triawan DA., Banon C., Adfa M., 2020. Biokonversi Kulit Kopi Menjadi Pupuk Kompos Pada Kelompok Tani Pangestu Rakyat Kabupaten Rejang Lebong. Jurnal Pengabdian Al-Ikhlas, 5(2), 159-165

The Endplate Role in Degenerative Disc Disease Research: The Isolation of Human Chondrocytes from Vertebral Endplate-An Optimised Protocol.

Background: Degenerative disc disease is a progressive and chronic disorder with many open questions regarding its pathomorphological mechanisms. In related studies, in vitro organ culture systems are becoming increasingly essential as a replacement option for laboratory animals. Live disc cells are highly appealing to study the possible mechanisms of intervertebral disc (IVD) degeneration. To study the degenerative processes of the endplate chondrocytes in vitro, we established a relatively quick and easy protocol for isolating human chondrocytes from the vertebral endplates. Methods: The fragments of human lumbar endplates following lumbar fusion were collected, cut, ground and partially digested with collagenase I in Advanced DMEM/F12 with 5% foetal bovine serum. The sediment was harvested, and cells were seeded in suspension, supplemented with special media containing high nutrient levels. Morphology was determined with phalloidin staining and the characterisation for collagen I, collagen II and aggrecan with immunostaining. Results: The isolated cells retained viability in appropriate laboratory conditions and proliferated quickly. The confluent culture was obtained after 14 days. Six to 8 h after seeding, attachments were observed, and proliferation of the isolated cells followed after 12 h. The cartilaginous endplate chondrocytes were stable with a viability of up to 95%. Pheno- and geno-typic analysis showed chondrocyte-specific expression, which decreased with passages. Conclusions: The reported cell isolation process is simple, economical and quick, allowing establishment of a viable long-term cell culture. The availability of a vertebral endplate cell model will permit the study of cell properties, biochemical aspects, the potential of therapeutic candidates for the treatment of disc degeneration, and toxicology studies in a well-controlled environment.

Distinct sources of bacterial branched GMGTs in the Godavari River basin (India) and Bay of Bengal sediments

Branched glycerol monoalkyl glycerol tetraethers (brGMGTs) are a group of membrane-spanning lipids produced by (yet) unidentified bacteria. They are characterized by a C-C bond connecting the two alkyl chains, which is thought to enhance membrane stability at higher temperatures. So far, they have been found in peats, lakes, and marine sediments, where their abundance relative to that of branched glycerol dialkyl glycerol tetraethers (brGDGTs) increases with temperature. However, the preferred niche(s) for production and the origin of brGMGTs in the terrestrial and marine realm remain unknown. Here we explore the occurrence of brGMGTs in soils, suspended particulate matter (SPM) and riverbed sediments in the Godavari River basin, and compare these with brGMGTs in a Holocene sediment core from the Bay of Bengal close to the Godavari River mouth. BrGMGTs are mostly detected in agricultural and/or regularly inundated soils, and in the river at sites with standing water and/or agricultural/wastewater effluents, as well as in the delta, where low oxygen conditions and/or high nutrient levels prevail. In contrast, brGMGTs are continuously present in the marine sediment core, but with a different isomeric composition than in the terrestrial realm, indicating a primarily marine source. The stable brGMGT distribution downcore and brGMGT-inferred temperature estimates which resemble the bottom water temperature, may suggest marine brGMGT production in the deep water column and/or sediments. However, to establish the proxy potential of brGMGTs for paleoreconstructions in the terrestrial and marine realm, brGMGT sources and environmental controls require further study.

Mutation of rpoB Shifts the Nutrient Threshold Triggering Myxococcus Multicellular Development.

The ability to perceive and respond to environmental change is essential to all organisms. In response to nutrient depletion, cells of the soil-dwelling δ-proteobacterium Myxococcus xanthus undergo collective morphogenesis into multicellular fruiting bodies and transform into stress-resistant spores. This process is strictly regulated by gene networks that incorporate both inter- and intracellular signals. While commonly studied M. xanthus reference strains and some natural isolates undergo development only in nutrient-poor conditions, some lab mutants and other natural isolates commit to development at much higher nutrient levels, but mechanisms enabling such rich medium development remain elusive. Here we investigate the genetic basis of rich medium development in one mutant and find that a single amino acid change (S534L) in RpoB, the β-subunit of RNA polymerase, is responsible for the phenotype. Ectopic expression of the mutant rpoB allele was sufficient to induce nutrient-rich development. These results suggest that the universal bacterial transcription machinery bearing the altered β-subunit can relax regulation of developmental genes that are normally strictly controlled by the bacterial stringent response. Moreover, the mutation also pleiotropically mediates a tradeoff in fitness during vegetative growth between high vs. low nutrient conditions and generates resistance to exploitation by a developmental cheater. Our findings reveal a previously unknown connection between the universal transcription machinery and one of the most behaviorally complex responses to environmental stress found among bacteria.

Estimating nutrient thresholds for eutrophication management: Novel insights from understudied lake types

Nutrient targets based on pressure-response models are essential for defining ambitions and managing eutrophication. However, the scale of biogeographical variation in these pressure-response relationships is poorly understood, which may hinder eutrophication management in regions where lake ecology is less intensively studied. In this study, we derive ecology-based nutrient targets for five major ecoregions of Europe: Northern, Central-Baltic, Alpine, Mediterranean and Eastern Continental. As a first step, we developed regressions between nutrient concentrations and ecological quality ratios (EQR) based on phytoplankton and macrophyte communities. Significant relationships were established for 13 major lake types; in most cases, these relationships were stronger for phosphorus than for nitrogen, and stronger for phytoplankton than for macrophytes. Using these regressions, we estimated the total phosphorus (TP) and total nitrogen (TN) concentrations at which lakes of different types are likely to achieve good ecological status. However, in the very shallow lakes of the Eastern Continental region, relations between nutrient and biological communities were weak or non-significant. This can be attributed to high nutrient concentrations (in the asymptotic zone of phosphorus-phytoplankton models) suggesting other factors (light, grazing) limit primary production. However, we also show that fish stocking is a major pressure on Eastern Continental lakes, negatively affecting ecological status: lakes with low fish stocking show low chlorophyll-a concentrations and good ecological status despite high nutrient levels, while the lakes with high fish stocking show high chlorophyll-a and low ecological status. This study highlights the need to better understand lakes in biogeographic regions that have been, for historical reasons, less studied. This, in turn, helps reveal factors that challenge the dominant paradigms of lake assessment and management.

Future flavours from the past: Sensory and nutritional profiles of green plum (Buchanania obovata), red bush apple (Syzygium suborbiculare) and wild peach (Terminalia carpentariae) from East Arnhem Land, Australia

The green plum (Buchanania obovata), red bush apple (Syzygium suborbiculare) and wild peach (Terminalia carpentariae) all grow in remote East Arnhem Land, Australia and are eaten by the Yolŋu Aboriginal people who live there. These three fruits have had very little study at present by western food science and there is interest in their use as foods or food products to create sustainable Indigenous agribusinesses. The purpose of this study was to create a nutritional and sensory profile of each fruit. Results show that wild peach is a very good source of vitamin C with 2041 ± 192 mg/100g FW (fresh weight) and green plum is a very good source of folate, containing 118 ± 8 µg/100g FW as folic acid equivalents. All three fruit are good sources of dietary fibre, (green plum 9.5 ± 1.4, red bush apple 6.5 ± 1.0 and wild peach 8.6 ± 1.3 g/100g FW) and minerals and the green plum is a particularly valuable source of potassium (511 ± 22 mg/100g FW). Descriptive analysis of the fruit as whole or pieces of fruit, as a puree and as an ingredient (freeze-dried powder) in semolina and yoghurt describe the green plums flavour as sweet, tart and stewed apple and red bush apple as sour, raspberry, citrus, apple, sweet, floral, herbaceous and spiced tea. The unique sensory profiles and high nutrient levels indicate they could be used as future smart foods for diet diversity and future flavours in novel food products.

TDZ induces a dual morphogenetic pathway on leaf explants of the beach huckleberry – Gaylussacia brasiliensis

Gaylussacia brasiliensis is a bush from the Ericaceae family native to South America. It is considered an underutilized fruit species, despite its importance as a food source, medicinal plant, and forage for the native fauna. In the Florianópolis island, south of Brazil, it occurs in sand deposits between the Atlantic Ocean and the mountain chains of the Atlantic Rain Forest, in a vegetation type called “Restinga”, a harsh environment where plants are exposed to stressful conditions. Constand winds, high solar radiation, saltwater sprays, and low nutrient levels are common in the Restinga environment, making G. brasiliensis an important genetic resource to face the expected effects of climate change. Despite its importance, there are no sexual or asexual protocols available for its propagation. This is the first record of a micropropagation protocol for a plant of the Gaylussacia genus. We report a reliable protocol for in vitro establishment of G. brasiliensis cultures from seeds, and an efficient micropropagation protocol using leaf explants. A dual regeneration pathway, i.e., somatic embryos and adventitious shoots, can be obtained directly from leaf explants without an intermediating callus tissue. A low concentration of TDZ can be used to achieve this goal, and a high number of plants can be obtained rapidly, allowing advances in the research of this underutilized plant species and enabling its propagation for commercial or conservation purposes.

MicroRNA Mediated Plant Responses to Nutrient Stress.

To complete their life cycles, plants require several minerals that are found in soil. Plant growth and development can be affected by nutrient shortages or high nutrient availability. Several adaptations and evolutionary changes have enabled plants to cope with inappropriate growth conditions and low or high nutrient levels. MicroRNAs (miRNAs) have been recognized for transcript cleavage and translational reduction, and can be used for post-transcriptional regulation. Aside from regulating plant growth and development, miRNAs play a crucial role in regulating plant’s adaptations to adverse environmental conditions. Additionally, miRNAs are involved in plants’ sensory functions, nutrient uptake, long-distance root transport, and physiological functions related to nutrients. It may be possible to develop crops that can be cultivated in soils that are either deficient in nutrients or have extreme nutrient supplies by understanding how plant miRNAs are associated with nutrient stress. In this review, an overview is presented regarding recent advances in the understanding of plants’ responses to nitrogen, phosphorus, potassium, sulfur, copper, iron, boron, magnesium, manganese, zinc, and calcium deficiencies via miRNA regulation. We conclude with future research directions emphasizing the modification of crops for improving future food security.