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1.
Water Res ; 263: 122160, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39096816

RESUMEN

The accurate prediction of chlorophyll-a (chl-a) concentration in coastal waters is essential to coastal economies and ecosystems as it serves as the key indicator of harmful algal blooms. Although powerful machine learning methods have made strides in forecasting chl-a concentrations, there remains a gap in effectively modeling the dynamic temporal patterns and dealing with data noise and unreliability. To wiggle out of quagmires, we introduce an innovative deep learning prediction model (termed ChloroFormer) by integrating Transformer networks with Fourier analysis within a decomposition architecture, utilizing coastal in-situ data from two distinct study areas. Our proposed model exhibits superior capabilities in capturing both short-term and middle-term dependency patterns in chl-a concentrations, surpassing the performance of six other deep learning models in multistep-ahead predictive accuracy. Particularly in scenarios involving extreme and frequent blooms, our proposed model shows exceptional predictive performance, especially in accurately forecasting peak chl-a concentrations. Further validation through Kolmogorov-Smirnov tests attests that our model not only replicates the actual dynamics of chl-a concentrations but also preserves the distribution of observation data, showcasing its robustness and reliability. The presented deep learning model addresses the critical need for accurate prediction on chl-a concentrations, facilitating the exploration of marine observations with complex dynamic temporal patterns, thereby supporting marine conservation and policy-making in coastal areas.


Asunto(s)
Clorofila A , Monitoreo del Ambiente , Análisis de Fourier , Monitoreo del Ambiente/métodos , Clorofila/análisis , Agua de Mar/química , Predicción , Aprendizaje Profundo
2.
Sci Rep ; 14(1): 19856, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39191888

RESUMEN

This study aimed to reveal the diversity and variation in panicle traits of the Chinese prickly ash and clarify their influence on the its systematic classification to provide a theoretical basis and technical support for the efficient utilization of Chinese prickly ash germplasm resources and breeding. Sixteen panicle traits were identified from 35 Chinese prickly ash germplasm resources from 2021 to 2022. The diversity of these panicle traits and their role in the plant's systematic classification were studied using variance, correlation, cluster, and principal component analyses. Cluster analysis showed that the 35 Chinese prickly ash germplasm resources could be divided into two groups with Euclidean distances of 25. Further analysis showed that yield traits such as panicle length, panicle width, primary branching, grain number per panicle, and grain weight per panicle were significantly positively correlated with grain chlorophyll content, while grain anthocyanin content was negatively correlated with both panicle (panicle length, panicle width, panicle length to width ratio, primary branching, grain number per panicle, and grain weight per panicle) and grain characteristics (single grain weight, thousand-grain weight, grain length, grain width and fruit shape index). In conclusion, Chinese prickly ash germplasms have diverse panicle traits. Z. armatum has dark green grains, long and wide panicles, a long conical shape, many primary branches, high grain weight, and high grain number per panicle. In contrast, Z. bungeanum has bright red seeds, a panicle width larger than its length, short and conical panicles, a small number of primary branches, and low grain weight per panicle and number of grains per panicle. Overall, Z. armatum had a significant yield advantage over Z. bungeanum.


Asunto(s)
Semillas , China , Semillas/crecimiento & desarrollo , Semillas/anatomía & histología , Grano Comestible/crecimiento & desarrollo , Grano Comestible/anatomía & histología , Carácter Cuantitativo Heredable , Fenotipo , Análisis por Conglomerados , Fitomejoramiento , Variación Genética , Análisis de Componente Principal , Clorofila/análisis , Clorofila/metabolismo , Pueblos del Este de Asia
3.
Food Res Int ; 192: 114787, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147489

RESUMEN

This original work investigated the optical properties and Monte-Carlo (MC) based simulation of light propagation in the flavedo of Nanfeng tangerine (NF) and Gannan navel orange (GN) infected by Penicillium italicum. The increase of absorption coefficient (µa) at around 482 nm and the decrease at around 675 nm were both observed in infected NF and GN during storage, indicating the accumulation of carotenoids and loss of chlorophyll. Particularly, the µa in NF varied more intensively than GN, but the limited differences of reduced scattering coefficient (µs') were detected while postharvest infection. Besides, MC simulation of light propagation indicated that the photon packets weight and penetration depth at 482 nm in NF were reduced more than in GN flavedo, while there were almost no changes at the relatively low absorption wavelength of 926 nm. The simulated absorption energy at 482 nm in NF and GN presented more changes than those at 675 nm during infection, thus could provide better detection of citrus diseases. Furthermore, PLS-DA models can discriminate healthy and infected citrus, with the accuracy of 95.24 % for NF and 98.67 % for GN, respectively. Consequently, these results can provide theoretical fundamentals to improve modelling prediction robustness and accuracy.


Asunto(s)
Citrus , Luz , Método de Montecarlo , Penicillium , Citrus/microbiología , Enfermedades de las Plantas/microbiología , Clorofila/análisis , Frutas/microbiología , Carotenoides/análisis , Carotenoides/metabolismo
4.
Mar Environ Res ; 200: 106668, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39116738

RESUMEN

Phytoplankton responds rapidly to nutrient availability variations, becoming a useful indicator for eutrophication and/or management actions to reduce it. The present study evaluated the medium-term response of the phytoplankton community of a temperate estuary (Urdaibai estuary) to the cessation of discharges from a wastewater treatment-plant (WWTP), comparing the physicochemical conditions and the phytoplankton community before (2020) and after (2022) the sewerage works. The cessation led to a decrease of ammonium and phosphate, causing decreases of phytoplankton biomass in the outer and middle estuary and increases in the surroundings of the WWTP. Community composition also changed, recording an increase of prasinoxanthin-containing algae's contribution to total biomass, and a composition shift in the inner estuary, from mainly flagellates (alloxanthin-containing and chlorophyll b-containing algae) to the increase of diatoms, which could be prompted by the change of nutrient-ratios and the nitrogen source, and might indicate the recuperation of the system.


Asunto(s)
Monitoreo del Ambiente , Estuarios , Fitoplancton , Aguas Residuales , Aguas Residuales/química , Eutrofización , Cromatografía Líquida de Alta Presión , Clorofila/análisis , Eliminación de Residuos Líquidos/métodos , Biomasa
5.
Sensors (Basel) ; 24(15)2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39123831

RESUMEN

Chlorophyll fluorescence is a well-established method to estimate chlorophyll content in leaves. A popular fluorescence-based meter, the Opti-Sciences CCM-300 Chlorophyll Content Meter (CCM-300), utilizes the fluorescence ratio F735/F700 and equations derived from experiments using broadleaf species to provide a direct, rapid estimate of chlorophyll content used for many applications. We sought to quantify the performance of the CCM-300 relative to more intensive methods, both across plant functional types and years of use. We linked CCM-300 measurements of broadleaf, conifer, and graminoid samples in 2018 and 2019 to high-performance liquid chromatography (HPLC) and/or spectrophotometric (Spec) analysis of the same leaves. We observed a significant difference between the CCM-300 and HPLC/Spec, but not between HPLC and Spec. In comparison to HPLC, the CCM-300 performed better for broadleaves (r = 0.55, RMSE = 154.76) than conifers (r = 0.52, RMSE = 171.16) and graminoids (r = 0.32, RMSE = 127.12). We observed a slight deterioration in meter performance between years, potentially due to meter calibration. Our results show that the CCM-300 is reliable to demonstrate coarse variations in chlorophyll but may be limited for cross-plant functional type studies and comparisons across years.


Asunto(s)
Clorofila , Hojas de la Planta , Clorofila/análisis , Clorofila/química , Cromatografía Líquida de Alta Presión , Hojas de la Planta/química , Plantas/química , Plantas/metabolismo , Fluorescencia , Espectrofotometría/métodos , Reproducibilidad de los Resultados , Calibración
6.
Anal Methods ; 16(33): 5652-5664, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39109659

RESUMEN

The intricate composition of microalgal pigments plays a crucial role in various biological processes, from photosynthesis to biomarker identification. Traditional pigment analysis methods involve complex extraction techniques, posing challenges in maintaining analyte integrity. In this study, we employ Electron Transfer Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (ET-MALDI-MS) to compare the pigmentary profiles of Chlorella vulgaris intact cells, chloroplasts, and solvent extracts. We aim to obtain comprehensive extracts rich in polar and non-polar compounds using ultrasound-assisted and supercritical fluid extraction methods. Additionally, intact chloroplasts are isolated using a lysis buffer and sucrose density gradient centrifugation. Our ET-MALDI-MS analysis reveals distinct compositional differences, highlighting the impact of extraction protocols on microalgal pigment identification. We observe prominent signals corresponding to radical cations of key pigments, including chlorophylls and carotenoids, which are crucial for C. vulgaris identification. Furthermore, ET-MALDI-MS facilitates the identification of specific lipids within chloroplast membranes and other organelles. This study underscores the rapid and precise nature of ET-MALDI-MS in microalgal biomarker analysis, providing valuable insights into phytoplankton dynamics, trophic levels, and environmental processes. C. vulgaris emerges as a promising model for studying pigment composition and membrane lipid diversity, enhancing our understanding of microalgal ecosystems.


Asunto(s)
Chlorella vulgaris , Cloroplastos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Chlorella vulgaris/química , Chlorella vulgaris/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Cloroplastos/química , Cloroplastos/metabolismo , Carotenoides/análisis , Carotenoides/química , Clorofila/análisis , Clorofila/química , Pigmentos Biológicos/análisis , Pigmentos Biológicos/química
7.
Braz J Biol ; 84: e283148, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39194014

RESUMEN

The use of indices is recommended for continuous monitoring and assessment of aquatic ecosystems, as they summarize the technical complexity of the results of multiple analyzes performed and translate these results into quality classes that reflect the actions taken and indicate ways to recover and conserve the resources. Environmental trophic state indices provide information on how nutrients, light availability and other factors promote the development of algal biomass and contribute to increased enrichment status of aquatic systems. Lamparelli's Trophic State Index (TSI) distinguishes between lentic (lower phytoplankton productivity) and lotic (higher phosphorus concentrations and lower chlorophyll-a concentrations) environments. The Aquatic Life Protection Index (ALPI) reflects water quality based on the trophic state of the environment, determines the degree of toxicity to biota and indicates deficiencies in variables and conditions essential for the protection of aquatic life. The indices were applied to a long data series to monitor the Guarapiranga Reservoir, an urban reservoir in the state of São Paulo in southeastern Brazil, which suffers from the urbanization of its surroundings and the discharge of domestic wastewater. The evaluation of the time series from 1978 to 2021 using these indices showed a deterioration in the trophic status and conservation of aquatic life in the reservoir and in one of its tributaries. Considering that the joint assessment of the two indices provides an approach to environmental conservation, their long-term use reflected changes and impacts on the environment and showed the best-preserved sites. Both indices are suitable for application in a baseline network in subtropical environments. They can pinpoint locations for better monitoring and are sensitive to environmental changes.


Asunto(s)
Monitoreo del Ambiente , Brasil , Monitoreo del Ambiente/métodos , Ecosistema , Calidad del Agua , Fitoplancton/clasificación , Fitoplancton/fisiología , Animales , Fósforo/análisis , Estaciones del Año , Biomasa , Clorofila/análisis , Clorofila A/análisis
8.
PLoS One ; 19(8): e0308826, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39186505

RESUMEN

Estimation of fruit quality parameters are usually based on destructive techniques which are tedious, costly and unreliable when dealing with huge amounts of fruits. Alternatively, non-destructive techniques such as image processing and spectral reflectance would be useful in rapid detection of fruit quality parameters. This research study aimed to assess the potential of image processing, spectral reflectance indices (SRIs), and machine learning models such as decision tree (DT) and random forest (RF) to qualitatively estimate characteristics of mandarin and tomato fruits at different ripening stages. Quality parameters such as chlorophyll a (Chl a), chlorophyll b (Chl b), total soluble solids (TSS), titratable acidity (TA), TSS/TA, carotenoids (car), lycopene and firmness were measured. The results showed that Red-Blue-Green (RGB) indices and newly developed SRIs demonstrated high efficiency for quantifying different fruit properties. For example, the R2 of the relationships between all RGB indices (RGBI) and measured parameters varied between 0.62 and 0.96 for mandarin and varied between 0.29 and 0.90 for tomato. The RGBI such as visible atmospheric resistant index (VARI) and normalized red (Rn) presented the highest R2 = 0.96 with car of mandarin fruits. While excess red vegetation index (ExR) presented the highest R2 = 0.84 with car of tomato fruits. The SRIs such as RSI 710,600, and R730,650 showed the greatest R2 values with respect to Chl a (R2 = 0.80) for mandarin fruits while the GI had the greatest R2 with Chl a (R2 = 0.68) for tomato fruits. Combining RGB and SRIs with DT and RF models would be a robust strategy for estimating eight observed variables associated with reasonable accuracy. Regarding mandarin fruits, in the task of predicting Chl a, the DT-2HV model delivered exceptional results, registering an R2 of 0.993 with an RMSE of 0.149 for the training set, and an R2 of 0.991 with an RMSE of 0.114 for the validation set. As well as for tomato fruits, the DT-5HV model demonstrated exemplary performance in the Chl a prediction, achieving an R2 of 0.905 and an RMSE of 0.077 for the training dataset, and an R2 of 0.785 with an RMSE of 0.077 for the validation dataset. The overall outcomes showed that the RGB, newly SRIs as well as DT and RF based RGBI, and SRIs could be used to evaluate the measured parameters of mandarin and tomato fruits.


Asunto(s)
Carotenoides , Clorofila , Frutas , Aprendizaje Automático , Solanum lycopersicum , Solanum lycopersicum/crecimiento & desarrollo , Frutas/química , Frutas/crecimiento & desarrollo , Clorofila/análisis , Carotenoides/análisis , Carotenoides/metabolismo , Licopeno/análisis , Clorofila A/análisis , Citrus/crecimiento & desarrollo , Imágenes Hiperespectrales/métodos
9.
Astrobiology ; 24(7): 710-720, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39023355

RESUMEN

In a previous experiment, we demonstrated the capability of flow cytometry as a potential life detection technology for icy moons using exogenous fluorescent stains (Wallace et al., 2023). In this companion experiment, we demonstrated the capability of flow cytometry to detect life using intrinsically fluorescent biomolecules in addition to exogenous stains. We used a method similar to our previous work to positively identify six classes of intrinsically fluorescent biomolecules: flavins, carotenoids, chlorophyll, tryptophan, NAD+, and NAD(P)H. We demonstrated the effectiveness of this method with six known organisms and known abiotic material and showed that the cytometer is easily able to distinguish the known organisms and the known abiotic material by using the intrinsic fluorescence of these six biomolecules. To simulate a life detection experiment on an icy moon lander, we used six natural samples with unknown biotic and abiotic content. We showed that flow cytometry can identify all six intrinsically fluorescent biomolecules and can separate the biotic material from the known abiotic material on scatter plots. The use of intrinsically fluorescent biomolecules in addition to exogenous stains will potentially cast a wider net for life detection on icy moons using flow cytometry.


Asunto(s)
Citometría de Flujo , Citometría de Flujo/métodos , Colorantes Fluorescentes/química , Fluorescencia , Exobiología/métodos , Triptófano/análisis , Clorofila/análisis , NAD/análisis , Carotenoides/análisis , NADP/análisis
10.
World J Microbiol Biotechnol ; 40(9): 272, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39030303

RESUMEN

Microalgae are a source of a wide variety of commodities, including particularly valuable pigments. The typical pigments present in microalgae are the chlorophylls, carotenoids, and phycobiliproteins. However, other types of pigments, of the family of water-soluble polyphenols, usually encountered in terrestrial plants, have been recently reported in microalgae. Among such microalgal polyphenols, many flavonoids have a yellowish hue, and are used as natural textile dyes. Besides being used as natural colorants, for example in the food or cosmetic industry, microalgal pigments also possess many bioactive properties, making them functional as nutraceutical or pharmaceutical agents. Each type of pigment, with its own chemical structure, fulfills particular biological functions. Considering both eukaryotes and prokaryotes, some species within the four most promising microalgae groups (Cyanobacteria, Rhodophyta, Chlorophyta and Heterokontophyta) are distinguished by their high contents of specific added-value pigments. To further enhance microalgae pigment contents during autotrophic cultivation, a review is made of the main related strategies adopted during the last decade, including light adjustments (quantity and quality, and the duration of the photoperiod cycle), and regard to mineral medium characteristics (salinity, nutrients concentrations, presence of inductive chemicals). In contrast to what is usually observed for growth-related pigments, accumulation of non-photosynthetic pigments (polyphenols and secondary carotenoids) requires particularly stressful conditions. Finally, pigment enrichment is also made possible with two new cutting-edge technologies, via the application of metallic nanoparticles or magnetic fields.


Asunto(s)
Microalgas , Pigmentos Biológicos , Microalgas/metabolismo , Microalgas/química , Pigmentos Biológicos/química , Carotenoides/química , Carotenoides/metabolismo , Carotenoides/análisis , Ficobiliproteínas/química , Ficobiliproteínas/metabolismo , Cianobacterias/metabolismo , Cianobacterias/química , Rhodophyta/química , Rhodophyta/metabolismo , Chlorophyta/química , Chlorophyta/metabolismo , Clorofila/análisis , Polifenoles/análisis , Polifenoles/química , Polifenoles/metabolismo , Medios de Cultivo/química
11.
Food Chem ; 459: 140360, 2024 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38991443

RESUMEN

Methyl jasmonate (MJ) has potential to regulate fruit ripening and quality. 'Yoho' and 'Jiro' persimmons were sprayed with MJ (0, 2, 4, and 6 mM), four weeks before anticipated harvest to evaluate its effects on fruit colour and bioactive compounds. Preharvest MJ application significantly improved fruit colour with increased a*, b*, chroma, and colour index. The MJ 6 mM application had significantly enhanced soluble solids content (SSC), reduced total chlorophyll content in peel and pulp, and soluble and total tannins in persimmons. MJ treatments exhibited higher contents of total phenolics, flavonoids, carotenoids, and antioxidant activities. Additionally, MJ treatments enhanced the activities of shikimate dehydrogenase (SKDH), phenylalanine ammonia-lyase (PAL), catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) and lipoxygenase (LOX) enzymes. Overall, pre-harvest MJ application at 6 mM four weeks before anticipated harvest could be useful for advancing colour and improving bioactive compounds in 'Yoho' and 'Jiro' persimmons.


Asunto(s)
Acetatos , Antioxidantes , Color , Ciclopentanos , Diospyros , Frutas , Oxilipinas , Oxilipinas/farmacología , Oxilipinas/metabolismo , Antioxidantes/metabolismo , Ciclopentanos/farmacología , Ciclopentanos/metabolismo , Frutas/química , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Frutas/efectos de los fármacos , Acetatos/farmacología , Acetatos/metabolismo , Diospyros/química , Diospyros/crecimiento & desarrollo , Diospyros/metabolismo , Proteínas de Plantas/metabolismo , Fenoles/metabolismo , Fenoles/análisis , Reguladores del Crecimiento de las Plantas/farmacología , Reguladores del Crecimiento de las Plantas/metabolismo , Flavonoides/análisis , Flavonoides/metabolismo , Superóxido Dismutasa/metabolismo , Clorofila/metabolismo , Clorofila/análisis , Carotenoides/metabolismo , Carotenoides/análisis
12.
Sci Rep ; 14(1): 16298, 2024 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009635

RESUMEN

Harmful algae blooms are a rare phenomenon in rivers but seem to increase with climate change and river regulation. To understand the controlling factors of cyanobacteria blooms that occurred between 2017 and 2020 over long stretches (> 250 km) of the regulated Moselle River in Western Europe, we measured physico-chemical and biological variables and compared those with a long-term dataset (1997-2016). Cyanobacteria (Microcystis) dominated the phytoplankton community in the late summers of 2017-2020 (cyano-period) with up to 110 µg Chlorophyll-a/L, but had not been observed in the river in the previous 20 years. From June to September, the average discharge in the Moselle was reduced to 69-76% and water temperature was 0.9-1.8 °C higher compared to the reference period. Nitrogen (N), phosphorus (P) and silica (Si) declined since 1997, albeit total nutrient concentrations remained above limiting conditions in the study period. Cyanobacterial blooms correlated best with low discharge, high water temperature and low nitrate. We conclude that the recent cyanobacteria blooms have been caused by dry and warm weather resulting in low flow conditions and warm water temperature in the regulated Moselle. Under current climate projections, the Moselle may serve as an example for the future of regulated temperate rivers.


Asunto(s)
Cambio Climático , Cianobacterias , Ríos , Ríos/microbiología , Cianobacterias/crecimiento & desarrollo , Temperatura , Fitoplancton/crecimiento & desarrollo , Estaciones del Año , Fósforo/análisis , Nitrógeno/análisis , Clorofila A/análisis , Clorofila/análisis , Floraciones de Algas Nocivas , Plancton/crecimiento & desarrollo , Eutrofización , Monitoreo del Ambiente/métodos
13.
Sci Total Environ ; 949: 175099, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39079642

RESUMEN

According to previous studies, marine heatwaves (MHWs) significantly suppress the phytoplankton chlorophyll-a concentration (Chl a) in tropical oceans. However, pre-MHW Chl a has rarely been considered as a reference value. In this study, the Chl a for the periods preceding and during MHWs events was used to explore the impact of MHWs on Chl a from 1998 to 2022 in the South China Sea (SCS). The Chl a response to MHWs in different regions was further discussed based on the Chl a variation characteristics. The results showed that the Chl a response to MHWs exhibited regional variability. Interestingly, there was a large proportion of positive Chl a anomalies (∼0.55) in the estuary and offshore regions during MHWs; however, Chl a anomalies were mostly negative in the upwelling regions. These different response patterns are related to background conditions, including nutrient concentrations, wind-driven dynamics, and light availability. In upwelling regions, negative Chl a anomalies were primarily due to the weakening of wind speeds, Ekman pumping velocities, and upwelling intensities. In estuarine regions, positive Chl a anomalies were caused by enhanced light availability, whereas in offshore regions, there were attributed to the increased atmospheric wet deposition. These results have improved our understanding of the impact of MHWs on marine ecosystems.


Asunto(s)
Clorofila A , Monitoreo del Ambiente , Fitoplancton , China , Clorofila/análisis , Agua de Mar/química , Océanos y Mares , Calor
14.
PeerJ ; 12: e17698, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39071122

RESUMEN

Despite their overlooked status, weeds are increasingly recognized for their therapeutic value, aligning with historical reliance on plants for medicine and nutrition. This study investigates the medicinal potential of native weed species in Bangladesh, specifically pigments, antioxidants, and free radical scavenging abilities. Twenty different medicinal weed species were collected from the vicinity of Khulna Agricultural University and processed in the Crop Botany Department Laboratory. Pigment levels were determined using spectrophotometer analysis, and phenolics, flavonoids, and DPPH were quantified accordingly. Chlorophyll levels in leaves ranged from 216.70 ± 9.41 to 371.14 ± 28.67 µg g-1 FW, and in stems from 51.98 ± 3.21 to 315.89 ± 17.19 µg g-1 FW. Flavonoid content also varied widely, from 1,624.62 ± 102.03 to 410.00 ± 115.58 mg CE 100 g-1 FW in leaves, and from 653.08 ± 32.42 to 80.00 ± 18.86 mg CE 100 g-1 FW in stems. In case of phenolics content Euphorbia hirta L. displaying the highest total phenolic content in leaves (1,722.33 ± 417.89 mg GAE 100 g-1 FW) and Ruellia tuberosa L. in stems (977.70 ± 145.58 mg GAE 100 g-1 FW). The lowest DPPH 2.505 ± 1.028 mg mL-1was found in Heliotropium indicum L. leaves. Hierarchical clustering links species with pigment, phenolic/flavonoid content, and antioxidant activity. PCA, involving 20 species and seven traits, explained 70.07% variability, with significant PC1 (14.82%) and PC2 (55.25%). Leaves were shown to be superior, and high-performing plants such as E. hirta and H. indicum stood out for their chemical composition and antioxidant activity. Thus, this research emphasizes the value of efficient selection while concentrating on the therapeutic potential of native weed species.


Asunto(s)
Antioxidantes , Depuradores de Radicales Libres , Malezas , Plantas Medicinales , Bangladesh , Antioxidantes/química , Antioxidantes/análisis , Antioxidantes/farmacología , Malezas/química , Depuradores de Radicales Libres/química , Plantas Medicinales/química , Hojas de la Planta/química , Flavonoides/análisis , Flavonoides/química , Fenoles/análisis , Fenoles/química , Extractos Vegetales/química , Pigmentos Biológicos/química , Pigmentos Biológicos/análisis , Clorofila/análisis
15.
J Contam Hydrol ; 265: 104388, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38964149

RESUMEN

The understanding of spatio-temporal variation in land use and land cover (LULC) patterns is crucial for managing catchment land use planning, as it directly influences of tropical reservoir water quality and the subsequent Nutrient Contamination (NC) of unmonitored water bodies. The current research attempts to accurately measure the influence of LULC and its associated determinants on the quantities of NC loads by using Chl-a as a proxy, within tropical reservoirs, i.e. Bhadra and Tungabhadra, located in same river catchment. This Chl-a spread calculated by the Maximum Chlorophyll Index (MCI) derived from Sentinel 2 satellite data products covering the period from July 2016 to June 2021 were done using Google Earth Engine (GEE) platform. The validation analysis confirms the robustness of the methodology with a strong correlation between MCI-calculated values and EOMAP (Earth Observation and Environmental Services Mapping) Chl-a (µg/L) data points for both reservoirs, Bhadra (R2 = 0.64) and Tungabhadra (R2 = 0.68). The findings reveal that, Tungabhadra reservoir consistently exhibits an excessive spatial distribution of Chl-a spread area (17 km2 to 335 km2), reflecting nutrient-rich water inflows, particularly evident during the post-monsoon period. This notable rise could be linked to harvesting the Kharif crop, resulting in elevated nutrient concentrations. In contrast Bhadra reservoir, dominated by forested areas, maintains relatively lower Chl-a spread areas (<20 km2), highlighting its pivotal role in maintaining water cleanliness and serves as a riparian boundary. In addition, the changes in LULC classes show a strong relationship with variation in Chl-a during the studied period, for the Bhadra Reservoir R2 = 0.51 (F- statistics = 3.983, p = 0.021), and the Tungabhadra Reservoir R2 = 0.802 (F- statistics = 7.489, p = 0.0143). This highlights how changes in land use significantly shape contamination dynamics, deepening our understanding of nutrient inputs and contamination drivers in tropical reservoirs.


Asunto(s)
Clorofila A , Monitoreo del Ambiente , India , Monitoreo del Ambiente/métodos , Clorofila A/análisis , Clorofila/análisis , Contaminantes Químicos del Agua/análisis , Clima Tropical , Ríos/química , Abastecimiento de Agua
16.
Sensors (Basel) ; 24(13)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-39001004

RESUMEN

The survival and growth of young plants hinge on various factors, such as seed quality and environmental conditions. Assessing seedling potential/vigor for a robust crop yield is crucial but often resource-intensive. This study explores cost-effective imaging techniques for rapid evaluation of seedling vigor, offering a practical solution to a common problem in agricultural research. In the first phase, nine lettuce (Lactuca sativa) cultivars were sown in trays and monitored using chlorophyll fluorescence imaging thrice weekly for two weeks. The second phase involved integrating embedded computers equipped with cameras for phenotyping. These systems captured and analyzed images four times daily, covering the entire growth cycle from seeding to harvest for four specific cultivars. All resulting data were promptly uploaded to the cloud, allowing for remote access and providing real-time information on plant performance. Results consistently showed the 'Muir' cultivar to have a larger canopy size and better germination, though 'Sparx' and 'Crispino' surpassed it in final dry weight. A non-linear model accurately predicted lettuce plant weight using seedling canopy size in the first study. The second study improved prediction accuracy with a sigmoidal growth curve from multiple harvests (R2 = 0.88, RMSE = 0.27, p < 0.001). Utilizing embedded computers in controlled environments offers efficient plant monitoring, provided there is a uniform canopy structure and minimal plant overlap.


Asunto(s)
Germinación , Lactuca , Plantones , Lactuca/crecimiento & desarrollo , Lactuca/fisiología , Germinación/fisiología , Plantones/crecimiento & desarrollo , Plantones/fisiología , Clorofila/análisis , Clorofila/metabolismo , Semillas/crecimiento & desarrollo , Semillas/fisiología
17.
An Acad Bras Cienc ; 96(suppl 2): e20230744, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39016362

RESUMEN

The Brazil-Malvinas Confluence (BMC) is a significant biological frontier where distinct currents meet, fostering optimal conditions for phytoplankton development. In this study we tested the hypothesis that eddys promote an increase in phytoplankton biomass at the Brazil-Malvinas Confluence (BMC), altering species diversity. Phytoplankton were collected with Niskin bottles and nutrient concentrations assessed at two depths (Surface and Deep Chlorophyll Maximum Layer - DCML) in areas outside and under the influence of Cold-Core (CCE) and Warm-Core (WCE) Eddies. Environmental variables were determined in situ using a CTD profiler. Four regions were separated based on environmental variables and phytoplankton species, namely, the Brazil Current (BC), Malvinas Current (MC), CCE, and WCE. Species diversity was higher in the eddies. The conditions of the WCE were different from those of the CCE, with low temperature and salinity and high cell density values in the latter. The phylum Bacillariophyta was predominant in terms of species richness in all regions and was responsible for the higher cell density in the MC, while dinoflagellates were dominant in the BC and eddies. Therefore, eddy activity alters the structure, diversity and biomass of the phytoplankton community in the BMC.


Asunto(s)
Biodiversidad , Biomasa , Fitoplancton , Fitoplancton/clasificación , Fitoplancton/crecimiento & desarrollo , Brasil , Estaciones del Año , Clorofila/análisis , Movimientos del Agua , Temperatura
18.
Braz J Biol ; 84: e284144, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39046053

RESUMEN

Fungi of the genus Trichoderma spp have been related to the production of hormones or correlated with growth factors, promoting greater efficiency in the use of some nutrients, thus allowing greater availability and absorption by plants. In this context, the objective of this study was to determine the dose of organomineral fertilizer from cupuaçu (Theobroma grandiflorum) residues and the efficiency of Trichoderma harzianum on the initial growth and morphophysiological quality of Mezilaurus itauba seedlings in the northern Amazon. Dose of 50% of the organomineral fertilizer from cupuaçu residues (ORFCup) with Trichoderma harzianum promotes better quality and robustness in Mezilaurus itauba seedlings. The presence of Trichoderma harzianum + 50% ORFCup promotes positive gains in the root biomass of Mezilaurus itauba seedlings. The presence of Trichoderma harzianum promotes an increase in chlorophylls a and b contents in Mezilaurus itauba seedlings. For the production of Mezilaurus itauba seedlings, it is recommended to use Trichoderma harzianum + 50% ORFCup, as it promoted increments in all physiological and morphological indices under the conditions of the present study.


Asunto(s)
Fertilizantes , Plantones , Plantones/microbiología , Plantones/crecimiento & desarrollo , Fertilizantes/análisis , Hypocreales/fisiología , Clorofila/análisis
19.
Bull Environ Contam Toxicol ; 113(1): 2, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38960950

RESUMEN

The COVID-19 pandemic's disruptions to human activities prompted serious environmental changes. Here, we assessed the variations in coastal water quality along the Caspian Sea, with a focus on the Iranian coastline, during the lockdown. Utilizing Chlorophyll-a data from MODIS-AQUA satellite from 2015 to 2023 and Singular Spectrum Analysis for temporal trends, we found a 22% Chlorophyll-a concentration decrease along the coast, from 3.2 to 2.5 mg/m³. Additionally, using a deep learning algorithm known as Long Short-Term Memory Networks, we found that, in the absence of lockdown, the Chlorophyll-a concentration would have been 20% higher during the 2020-2023 period. Furthermore, our spatial analysis revealed that 98% of areas experienced about 18% Chlorophyll-a decline. The identified improvement in coastal water quality presents significant opportunities for policymakers to enact regulations and make local administrative decisions aimed at curbing coastal water pollution, particularly in areas experiencing considerable anthropogenic stress.


Asunto(s)
COVID-19 , Clorofila A , Monitoreo del Ambiente , COVID-19/epidemiología , Monitoreo del Ambiente/métodos , Clorofila A/análisis , Irán , Humanos , Clorofila/análisis , SARS-CoV-2 , Calidad del Agua , Agua de Mar/química , Pandemias , Océanos y Mares , Contaminación del Agua/estadística & datos numéricos
20.
Sci Rep ; 14(1): 17573, 2024 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080438

RESUMEN

The oil obtained from black cumin (Nigella sativa) seeds has many health-effective properties, which is used in food applications and in traditional medicine. One practical method to extract its oil is mixing with other seeds such as sunflower (Helianthus anuus) seeds before oil extraction by press. The effectiveness of the cold-press oil obtained from the mixture of black cumin seeds (BS) and sunflower seeds (SF) in different proportions 100:0, 95:5, 90:10, 85:15 and 0:100 (w/w) was studied to evaluate their qualitative properties including peroxide value (PV), acid value, p-anisidine value (AnV), pigments (carotenoid and chlorophyll) content, polyphenols, and profile of fatty acids during heating process (30-150 min at 180 °C). The results revealed that the acid and p-anisidine value of the all samples enhanced with the extension of the heating time, and the peroxide value increased at the beginning of the heating and then decreased with the prolongation of the heating time (p < .05). With the increase of temperature and heating time, the peroxide of sunflower oil increased with a higher slope and speed than that of black seed and blends oil. Changes in the PV and AnV were the fastest in sunflower oil. Blending and heating caused considerable changes in the fatty acid composition of oils, especially myristic, palmitic, and stearic acids. Moreover, the levels of certain unsaturated fatty acids, namely linoleic, oleic, and linolenic acids declined after heating. The carotenoids, chlorophyll and total phenol content decreased gradually during heating treatments. Among extracted oils, SF:BS (15%) had the good potential for stability, with total phenol content of 95.92 (Caffeic acid equivalents/100 g), PV of 2.16 (meq O2/kg), AV of 2.59 (mg KOH/g oil), and AnV of 8.08 after the heating. In conclusion, oil extracted from the mixture of SF and BS can be used as salad and cooking oils with a high content of bioactive components and positive nutritional properties.


Asunto(s)
Helianthus , Calor , Nigella sativa , Aceites de Plantas , Semillas , Nigella sativa/química , Helianthus/química , Semillas/química , Aceites de Plantas/química , Aceites de Plantas/análisis , Ácidos Grasos/análisis , Clorofila/análisis , Peróxidos/análisis , Polifenoles/análisis , Polifenoles/química , Aceite de Girasol/química , Carotenoides/análisis , Carotenoides/química
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