Concentrations Of Constituents Research Articles

Chemical composition of cloud and rainwater at a high-altitude mountain site in western India: source apportionment and potential factors.

This study focuses on the chemical composition of cloud water (CW) and rainwater (RW) collected at Sinhagad, a high-altitude station (1450m AMSL) located in the western region of India. The samples were collected during the monsoon over two years (2016-2017). The chemical analysis suggests that the concentration of total ionic constituents was three times higher in CW than in RW, except for NH4+ (1.0) and HCO3- (0.6). Compared to RW, high concentrations of SO42- and NO3- were observed in CW. The weighted average RW pH (6.5 ± 0.3) was slightly more alkaline than CW pH (6.1 ± 0.5). This can be attributed to the high concentrations of neutralizing ions such as nss-Ca2+, nss-Mg2+, K+, and NH4+, indicating the greater extent of wet scavenging during rainfall. These ions counteract the acidity generated by SO42- and NO3-. A high correlation between Ca2+, Na+, K+, NO3-, and SO42- makes it difficult to estimate the contribution of SO42- from different sources. Anthropogenic sulfur emissions and soil dust significantly influence the ionic composition of clouds and rain. Positive matrix factorization (PMF) was used to identify the contribution of different sources to the samples. In the CW, the extracted factors were cooking and vehicles, aging sea salt, agriculture, and dust. In RW, the factors were industries, cooking and vehicles, agriculture and dust, and aging sea salt. The findings of this study have significant implications for the monsoon build-up, ecosystems, agriculture, and climate change.

Physiological and biochemical responses of okra (Abelmoschus esculentus) under salinity stress in Iran

Saline soil and water present significant agricultural challenges, particularly in arid and semi-arid regions like Iran. Around 15 % of Iran's land is categorized as saline. Salt stress disrupts various physiological processes in plants, leading to reduced crop yields. Considering the demand for food and the limitation of cultivated areas is rising, the cultivation of salt-resistant crops is gaining attention. This study was conducted to examine the morpho-physiological responses tolerance of a native cultivar of okra (Abelmoschus esculentus L. cv. White Ahvazi) under conditions of salinity stress. Understanding how this native cultivar responds to salinity stress is crucial for increasing its productivity. The okra seedlings were subjected to seven different levels of electrical conductivity (EC) (1.7 as control, 4.4, 6.2, 8.5, 10.6, 12.5, 14.4, and 15.8 mS/cm) after the appearance of their first true leaves by dissolving NaCl salt in Hoagland's nutrient solution. The results showed that morphological traits in the treated samples were not significantly different from the non-treated samples until EC reached a value of 10.6 mS/cm. The increases in EC from 1.7 to 10.6 mS/cm resulted in a significant rise in the antioxidant capacity and content of biochemical constituents. While salinity stress from EC 12.5 mS/cm onwards caused significant induction of hydrogen peroxide free radicals and peroxidation of membrane lipids. The yield was also significantly reduced at ECs of 12.5, 14.4, and 15.8 mS/cm, which were 31.1, 40.6, and 59.6 % less than control plants, respectively. Increasing salinity stress resulted in a remarkable reduction of photosynthetic pigments in plants as compared to the non-treated plants. Generally, it can be concluded that the White Ahvazi cultivar of okra commonly cultivated in Iran had a moderate tolerance to EC with a threshold of 10.6 mS/cm. Thus, this study can contribute towards enhancing food production in regions facing challenges related to salinity.

Developing a novel index for detection of optically shallow waters using multispectral satellite imagery and radiative transfer modelling

ABSTRACT Optical remote sensing of water quality has been problematic due to contamination of remote sensing observations by the sea-bottom effect over complex shallow or very clear waters. This has resulted in providing misleading information on the estimation of Water Constituent Concentrations (WCCs) retrieved from satellite images. In this research, we used Radiative Transfer (RT) Modelling to develop a simple and innovative index named the Sea-Bottom Effect Index (SEBEI) to readily determine water pixels contaminated by the sea-bottom effect, (hereafter named Optically Shallow Waters, (OSWs)) from remote sensing observations. To define the SEBEI, we initially assessed the influence of the sea-bottom on simulated water-leaving reflectance (R rs ) using RT Water-Sea-Bottom (WSB) modelling. This evaluation encompassed a range of water depths, seabed albedos, and WCCs (i.e. Chlorophyll-a (Chla) and Suspended Particulate Matter (SPM)). Next, we detected the most sensitive wavelengths (i.e. 750 nm, 810 nm, and 900 nm) to the seabed contribution on the simulated R rs spectra at the water surface level and developed the SEBEI. We validated the accuracy of the proposed SEBEI over a time series of MEdium Resolution Imaging Spectrometer (MERIS) and Ocean and Land Colour Instrument (OLCI) images captured during low and high tidal phases over shallow waters of the Dutch Wadden Sea, the Netherlands. The results indicate that the SEBEI effectively distinguishes between OSWs and Optically Deep Waters (ODWs) using satellite images (with an R2 value of ≥ 0.97 and a Root Mean Square Error (RMSE) of ≤ 0.65). The SEBEI can serve as an intermediate solution for detecting OSWs in multispectral and hyperspectral satellite images worldwide. It eliminates the need for ancillary datasets like bathymetry maps and significantly enhances the reliability of WCC maps produced over complex shallow coastal waters.

LaFeSi–LaFe13−xSix composites: Modulating magnetic and magnetocaloric properties through inherent stress manipulation

We examine structural and magnetic properties of a series of La–Fe–Si alloys in the region of concentrations where they naturally form two-phase LaFeSi–LaFe13−xSix composites with variable content and connectivity of LaFe13−xSix grains distributed within the LaFeSi matrix. Theoretical calculations confirm that the LaFeSi constituent is magnetically and structurally inert below room temperature and at pressures between −10 and 10 GPa. The LaFe13−xSix constituent, on the other hand, is magnetically and structurally active: it exhibits first-order magnetostructural transformations that, in addition to xSi, can be controlled with temperature, magnetic field, and pressure. In composites where the concentration of the inactive constituent is ∼70 wt. % or greater, the standard, single-step, LaFe13−xSix first-order phase transformation proceeds in two steps separated by over 30 K in a zero magnetic field. Increasing the magnetic field recouples the two steps and restores the single-step phase transformation pathway. We analyze the roles of stresses caused by both thermal expansion mismatch and the first-order magnetic phase transition in LaFe13−xSix to rationalize the observed physical behaviors that emerge as the temperature or/and magnetic field vary.

Metabolic picture of microbial interaction: chemical crosstalk during co-cultivation between three dominant genera of bacteria and fungi in medicinal plants rhizosphere.

Microbial communities affect several aspects of the earth's ecosystem through their metabolic interaction. The dynamics of this interaction emerge from complex multilevel networks of crosstalk. Elucidation of this interaction could help us to maintain the balance for a sustainable future. To investigate the chemical language among highly abundant microbial genera in the rhizospheres of medicinal plants based on the metabolomic analysis at the interaction level. Coculturing experiments involving three microbial species: Aspergillus (A), Trichoderma (T), and Bacillus (B), representing fungi (A, T) and bacteria (B), respectively. These experiments encompassed various interaction levels, including dual cultures (AB, AT, TB) and triple cultures (ATB). Metabolic profiling by LC-QTOFMS revealed the effect of interaction level on the productivity and diversity of microbial specialized metabolites. The ATB interaction had the richest profile, while the bacterial profile in the monoculture condition had the lowest. Two native compounds of the Aspergillus genus, aspergillic acid and the dipeptide asperopiperazine B, exhibited decreased levels in the presence of the AT interaction and were undetectable in the presence of bacteria during the interaction. Trichodermarin N and Trichodermatide D isolated from Trichoderma species exclusively detected during coexistence with bacteria (TB and ATB). These findings indicate that the presence of Bacillus activates cryptic biosynthetic gene clusters in Trichoderma. The antibacterial activity of mixed culture extracts was stronger than that of the monoculture extracts. The TB extract exhibited strong antifungal activity compared to the monoculture extract and other mixed culture treatments. The elucidation of medicinal plant microbiome interaction chemistry and its effect on the environment will also be of great interest in the context of medicinal plant health Additionally, it sheds light on the content of bioactive constituents,and facilitating the discovery of novel antimicrobials.

Under the Strong Influence of Human Activities: The Patterns and Controlling Factors of River Water Chemistry Changes—A Case Study of the Lower Yellow River

This study provides an in-depth analysis of the hydrochemical characteristics and their controlling factors in the lower reaches of the Yellow River. Through water quality sampling and analysis over two hydrological periods within a year, combined with hydrochemical methods and machine learning techniques, the study reveals the joint impact of natural factors and human activities on the spatiotemporal variations in hydrochemical constituents. The findings indicate that the water in the lower reaches of the Yellow River exhibits weak alkalinity (the pH is between 7 and 8), with the primary hydrochemical type being HCO3·SO4—Ca·Na·Mg. The temporal variation in the hydrochemical constituents is mainly influenced by rainfall, where nitrate levels are higher during the flood season due to the flushing effect of rainfall, whereas other hydrochemical constituents show an opposite temporal pattern due to the dilution effect of rainfall. The spatial variation in the Yellow River’s hydrochemistry is primarily controlled by a combination of human activities and rainfall. Using Gibbs diagram analysis, it is identified that rock weathering is the main source of ionic constituents, while agricultural fertilization, industrial emissions, and domestic wastewater discharge have significant impacts on the hydrochemical constituents. Compared to other rivers worldwide, the concentration of hydrochemical constituents in the lower reaches of the Yellow River is relatively high, especially nitrate and sulfate, which is closely related to the geological characteristics of the Yellow River basin and intense human activities in the middle and lower reaches. Principal component analysis reveals that the main controlling factors for hydrochemical constituents during the dry season in the lower reaches of the Yellow River are rock weathering dissolution and industrial activities, followed by domestic wastewater; during the flood season, the main controlling factors are rock weathering dissolution and industrial activities, followed by agricultural activities and domestic wastewater. The research findings provide theoretical support for water resource management and water quality protection in the lower reaches of the Yellow River.

Holistic optical water type classification for ocean, coastal, and inland waters

AbstractWater constituents exhibit diverse optical properties across ocean, coastal, and inland waters, which alter their remote‐sensing reflectance obtained via satellites. Optical water type (OWT) classifications utilized in satellite data processing aim to mitigate optical complexity by identifying fitting ocean color algorithms tailored to each water type. This facilitates comprehension of biogeochemical cycles ranging from local to global scales. Previous OWT frameworks have focused narrowly on either oceanic or inland waters and have relied too heavily on specific data collections. We propose a novel holistic OWT framework applicable to all natural waters, based on state‐of‐the‐art bio‐geo‐optical modeling and radiative transfer simulations that encompass different phytoplankton groups. This framework employs a “knowledge‐driven” paradigm, combining domain knowledge and insights from previous studies to simulate the reflectance spectrum from water constituent concentrations and inherent optical properties. Our method extracts optical variables to represent the full spectrum of reflectance, consolidating both spectral shape and magnitude. We apply the framework utilizing diverse in situ, synthetic, and satellite data (Sentinel‐3 OLCI) and demonstrate its better classifiability than other frameworks. This framework lays the foundation for comprehensive global monitoring of natural waters.

Alleviation of Salt Stress and Changes in Glycyrrhizic Acid Accumulation by Dark Septate Endophytes in Glycyrrhiza glabra Grown under Salt Stress.

This study aimed to investigate the mechanisms by which dark septate endophytes (DSE) regulate salt tolerance and the accumulation of bioactive constituents in licorice. First, the salt stress tolerance and resynthesis with the plant effect of isolated DSE from wild licorice were tested. Second, the performance of licorice inoculated with DSE, which had the best salt-tolerant and growth-promoting effects, was examined under salt stress. All isolated DSE showed salt tolerance and promoted plant growth, withCurvularia lunata D43 being the most effective. Under salt stress, C. lunata D43 could promote growth, increase antioxidant enzyme activities, enhance glycyrrhizic acid accumulation, improve key enzyme activities in the glycyrrhizic acid synthesis pathway, and induce the expression of the key enzyme gene and salt tolerance gene of licorice. The structural equation model demonstrated that DSE alleviate the negative effects of salt stress through direct and indirect pathways. Variations in key enzyme activities, gene expression, and bioactive constituent concentration can be attributed to the effects of DSE. These results contribute to revealing the value of DSE for cultivating medicinal plants in saline soils.

Drying kinetics and quality characteristics of exocarpium citreic grandis slices with hot air, vacuum, and microwave vacuum dryers

The study investigates the impact of different drying methods on the selection of thin-layer drying kinetic models, parameters, and quality for Exocarpium Citreic Grandis. This study investigates the drying characteristics, index constituents content, and microscopic structures of Exocarpium Citreic Grandis slices, subjected to three drying techniques: HAD (at 50, 60, 70∘C), VD (at 50, 60, 70∘C), and MVD (at 1000, 1500, 2000W). A thin-layer drying kinetic model was established. The findings demonstrated that the drying process was primarily dominated by the falling rate phase. When the drying temperature was 70∘C and the microwave power was 2000W, the HAD VD, and MVD took 120, 360, and 20 minutes respectively. By fitting six commonly used thin-layer drying models, it was discovered that the optimal mathematical models for HAD, VD, and MVD were the Page model, the Logarithmic model, and the Page model, respectively. The highest average R2 values were 0.9963, 0.9965, and 0.9964, and the lowest average RMSE values were 0.01782, 0.01704, and 0.0174 respectively. The effective diffusion coefficient increased with the drying temperature and microwave power, with MVD having the maximum coefficient. As the temperature and microwave power increased, the contents of naringin and rhoifolin decreased. However, the naringin content in MVD was 23.05% and 45.71% higher compared to hot air and VD respectively. The cross-section of Exocarpium Citreic Grandis dried via microwave vacuum exhibited a porous honeycomb structure with uniformly distributed spaces and larger pores, reflecting an expansion effect. The HAD process also resulted in a honeycomb-like structure, but with smaller pores. The VD process resulted in a layered structure with significant cell collapse. Microwave vacuum drying demonstrates superior energy efficiency and product quality compared to hot air and vacuum drying methods. The study finds that microwave drying does not have a destructive impact on the active compounds of Exocarpium Citreic Grandis. To facilitate large-scale, continuous production, microwave drying can be practically applied in industrial processing.

Influence of Major Polyphenols on the Anti-Candida Activity of Eugenia uniflora Leaves: Isolation, LC-ESI-HRMS/MS Characterization and In Vitro Evaluation.

The content of chemical constituents in Eugenia uniflora leaf extracts correlates positively with biological activities. The experimental objective was to carry out the phytochemical screening and purification of the major polyphenols from the leaves of E. uniflora. In addition, the anti-Candida activity of the hydroalcoholic extract, fraction, subfractions and polyphenols purified were evaluated. After partitioning of the extract with ethyl acetate, the fractions were chromatographed on Sephadex® LH-20 gel followed by RP-flash chromatography and monitored by TLC and RP-HPLC. The samples were characterized by mass spectrometry (LC-ESI-QTOF-MS2) and subjected to the microdilution method in 96-well plates against strains of C. albicans, C. auris, and C. glabrata. Myricitrin (93.89%; w/w; m/z 463.0876), gallic acid (99.9%; w/w; m/z 169.0142), and ellagic acid (94.2%; w/w; m/z 300.9988) were recovered. The polyphenolic fraction (62.67% (w/w) myricitrin) and the ellagic fraction (67.86% (w/w) ellagic acid) showed the best antifungal performance (MIC between 62.50 and 500 μg/mL), suggesting an association between the majority constituents and the antifungal response of E. uniflora derivatives. However, there is a clear dependence on the presence of the complex chemical mixture. In conclusion, chromatographic strategies were effectively employed to recover the major polyphenols from the leaves of the species.

Differential distribution of characteristic constituents in peel and pulp of Aurantii Fructus Immaturus (Citrus aurantium L.) using MALDI mass spectrometry imaging

Aurantii Fructus Immaturus (AFI) was structurally divided into two parts named “peel” and “pulp”. The exocarp and mesocarp of materials named “peel”. The endocarp separated into multiple compartments and the cystic hair attached to it named “pulp”. In order to explore the distribution and content of constituents in AFI, an efficient method to explore the distribution of constituents was developed based on matrix assisted laser desorption/ionization fourier transform ion cyclotron resonance mass spectrometry imaging (MALDI-FTICR-MSI). After simple processing, thirty-two constituents with distinct localization in the mass range of 101–1200 Da were identified by MALDI-FTICR-MSI. In addition, the identified four flavnoids (poncirin, sinensetin, 3,5,6,7,8,3′,4′-heptemthoxyflavone, and tangeritin) were analyzed for differences between using LC-MS. Quantitative analysis results supported the quantitative results from MALDI-FT-ICR-MSI. The results implied that different parts had different constituents in AFI, and demonstrated MALDI-MSI have high potential in the direct analysis of constituents.

Fabrication and catalytic assessment of Ni/Ce–Zr–O catalyst for enhanced hydrogen production via steam reforming of glycerol

The valorization of glycerol, a plentiful byproduct derived from the biodiesel industry, for green hydrogen production via steam reforming (GSR) has attracted considerable attention. Nevertheless, catalysts developed for GSR encounter critical obstacles related to thermal stability and coke deposition during prolonged operations. In this study, we strategically employed thermally stable ZrO2 as a support along with redox-active Ce as a promoter for Ni to optimize both the preparation method and constituent content of the Ce-promoted Ni/ZrO2 catalyst for GSR. The physicochemical properties of both fresh and GSR-used catalysts were investigated using a range of characterization techniques, including XRD, H2-TPR, SEM-EDS/TEM, N2 adsorption/desorption, and TGA. The results demonstrate that the sol-gel method yields a Ni/Ce–Zr–O catalyst with smaller Ni crystals and a higher surface nickel content compared to the step impregnation and co-precipitation methods, thereby achieving enhanced catalytic activity. Moreover, the catalyst prepared by the sol-gel method exhibited excellent activity stability at elevated feedstock concentrations. Furthermore, it has been determined that there is an optimized amount of Ce doping for the Ni/ZrO2 catalyst, which allows the catalyst to achieve the highest pore parameters and surface nickel content. Among the studied catalysts, the one containing 30/50 wt% of designed CeO2/ZrO2 achieved the highest and most stable H2 yield (4.32 mol⋅mol−1) and carbon gasification efficiency (70.28 %) during a 24-h's GSR with a feedstock concentration of 15 wt% at 500 °C (with a WHSV of 45 h−1). Importantly, this optimized Ni/Ce–Zr–O catalyst effectively eliminates the deposition of filamentous/crystallized coke during long-term GSR operation due to enhanced oxygen vacancies created by the formed CexZr1-xO2 species, making it highly promising for large-scale applications.

Influence of Aspergillus parasiticus on aflatoxins production and quality change in Chrysanthemum morifolium at various storage conditions

SummaryIn this study, a full factorial design with three temperature levels (20, 30 and 40 °C), three moisture content (MC) levels (8%, 15% and 22%), and four storage times (7, 14, 21 and 28 days) was used to investigate the changes of aflatoxins (AFs), active constituents, and antioxidant activities in Hangbaiju (HBJ, Chrysanthemum morifolium) after simulated inoculation with Aspergillus parasiticus. The results showed that AFs could be produced in the range of 20~30 °C and 8~22% MC after mould infection, but both mould growth and AFs production were inhibited under the tested MC condition at 40 °C. The analysis of variance (anova) indicated that the temperature, time, interaction between the temperature and time, and interaction between MC and time had significant effects on the total aflatoxins (AFTOT) accumulation. Under 20 and 30 °C, AFTOT in inoculated HBJ usually increased with the increase of MC and storage time, while its active constituents and antioxidant activities decreased with the increase of AFTOT under corresponding storage conditions. Pearson correlation analysis suggested that relatively stronger negative correlations were observed between luteolin‐7‐O‐glucoside (LUT7G), total phenolic content (TPC), total flavonoid content (TFC), and AFTOT. Grey correlation analysis (GCA) showed that antioxidant activity was highly linked to the content of active constituents, and the characteristic flavonoid LUT7G exhibited the highest grey correlation degrees (GCDs) in the three antioxidant activities. The AFTOT reached the highest level (31.15 μg kg−1) after 28 days of storage at 30 °C and 22% MC; meanwhile, LUT7G, TPC and TFC decreased by 93.66%, 20.77% and 55.50%, respectively, and all the three antioxidant activities indicated more than 25% reduction. This is the first study about the changes and relationships of AFTOT, active constituents and bioactivities in the medicinal food influenced by A. parasiticus under different storage conditions. These results provide important references to prevent AFs production and quality control for HBJ and other medicinal foods influenced by A. parasiticus in storage strategy.

BaHys—A Bayesian Modeling Framework for Long‐Term Concentration‐Discharge Hysteresis: A Case Study on Chloride

AbstractImproving river water quality requires a thorough understanding of the relationship between constituent concentration and water discharge during runoff events (i.e., C‐Q hysteresis), which may be strongly non‐linear. Analysis of C‐Q hysteresis on large temporal scales provides unprecedented insights into event dynamics and long‐term concentration trends in surface and groundwater. Despite the increasing availability of time series data on water quality, there are still limited quantitative modeling frameworks that enable this analysis. Here, we combine Bayesian modeling and an existing mass balance to model long‐term C‐Q hysteresis dynamics in multi‐decade constituent concentration and water discharge time series. We focus on the case study of chloride and demonstrate that our model can simultaneously characterize the size and rotation of C‐Q hysteresis, and diffuse and low‐flow inputs to constituent concentration using only time‐series data from the river Rhine. Over 28 years of monitoring, we find that chloride exhibits a dominant clockwise dilution behavior that does not vary considerably under different hydro‐climatic conditions, hinting to similar mobilization mechanisms over time. We also show decreasing chloride concentrations in surface and groundwater, due to the cessation of mining activities in the Rhine. Our approach uses uncertainty estimates to show the range within which model parameter values lie, aiding decision‐makers in a robust assessment of river water quality. We conclude that Bayesian modeling of C‐Q hysteresis provides a powerful framework for investigating long‐term contamination dynamics that can be extended to several constituents to find factors controlling their export, ultimately suggesting mitigation measures for river contamination.

Effect of post-harvest drying period on the chemical composition of Zingiber zerumbet Sm. Rhizomes essential oil and its biological activities.

Zingiber zerumbet Sm. (Family: Zingiberaceae) is an important perennial medicinal oil-bearing herb that is native to the Southeast Asia. This study examines the impact of different durations of post-harvest shade drying (ranging from 1 to 12months) on essential oil yield and chemical composition of Z. zerumbet, in comparison to the freshly collected oil sample. This study explores how post-harvest shade drying impact the composition and longevity of Z. zerumbet rhizomes as well as its antimicrobial, antibiofilm activity. The oils were analyzed for their chemical composition analysis using a gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The post-harvest periods of drying (1-12months) were discovered to enhance the concentration of marker constituents in the oil. The primary constituent, Zerumbone, was detected in concentrations ranging from 69.38 ± 5.63% to a maximum of 80.19 ± 1.53% as the drying duration of the rhizome was extended. The output of the essential oil was not significantly affected by drying times; however, it did have a noticeable impact on the proportions of monoterpenes. Both disc diffusion and broth microdilution assay were used in freshly collected Z. zerumbet oil for its antimicrobial potential against S. aureus, L. monocytogens, S. hominis, Salmonella enterica serovar Typhimurium, P. aeruginosa, S. intermedius, E. coli, and C. albicans. For the first time, the oil reported to exhibit antibiofilm activity against S. aureus which was validated using fluorescence microscopy, and effectively disrupts the biofilm by 47.38% revealing that essential oil was able to disintegrate the clusters of the pathogen. Z. zerumbet rhizome oil is effective to reduce food-borne microorganisms. Therefore, its essential oil, a natural source of bioactive zerumbone, may improve flavor, aroma, and preservation.

Quantitative and qualitative phytochemical analysis of ethanol leaf extract of Pleiocarpa mutica

This research project examined Pleiocarpa mutica leaf extract, extracted from ethanol using both quantitative and qualitative phytochemical analysis. Sourced is at Ugbene-Ajima in the Uzo-Uwani Local Government Area of Enugu State, Nigeria, where fresh Pleiocarpa mutica leaves were collected. After been gathered, the newly sprouted P. mutica leaves were cleaned. We then shade-dried the leaves until they were crispy, rotating them frequently to prevent them from rotting. A mechanical grinder was utilized to reduce the dried leaves to a powdered state while a maceration flask was used to macerate 1.5 kg of the known weight of the ground leaves in 10 liters of 100% ethanol. In using a muslin cloth, the mixture was filtered into a flask with a flat bottom after being left for 72 hours with irregular stirring. Quantitative phytochemical analysis procedures identified the specific concentration of a certain chemical constituent present in a plant sample using methods such as mass spectrometry, chromatography, and spectrophotometry. This makes it possible to determine the concentration of a component in the plant material. Qualitative phytochemical analysis techniques focus on identifying the presence or absence of several chemical groups in a plant sample. Discovering the existence of substances such as alkaloids, phenols, terpenoids, and flavonoids often requires a range of chemical analyses or the use of specific reagents. Thus, the standard quantitative and qualitative phytochemical analysis technique were used to investigate the chemical composition of plants and identify bioactive compounds that may offer nutritional, medicinal, or pharmacological advantages. Hence, it has been shown that the ethanol leaves extract of P. mutica contains various concentrations of phytochemical constituents, which might be responsible for its biological activities.

Multi-factor analysis of the quality of cellar mud of Luzhou-flavor liquor in Yibin production area.

The aim of this study was to conduct a thorough scientific investigation into the similarities and differences in the quality of the cellars of different Luzhou-flavor liquor wineries in Yibin production area and the reasons for them. This study analyzed cellar mud samples from five wineries in Yibin production area. The analysis of volatile flavor compounds was carried out using headspace solid-phase microextraction and gas chromatography-mass spectrometry. The bacterial and archaeal community structures and their correlations were analyzed by high-throughput sequencing. The study indicates that the Distillery A had the highest levels of ammonium nitrogen and effective phosphorus, Distillery F had the highest humus levels, and Distillery I had the highest pH levels. The community structure of the principal bacterial and archaeal communities in the five subterranean clays exhibited similarity, and all samples were dominated by Firmicutes as the primary bacterial group. However, there was variation in bacterial abundance. The cellar mud also has obvious regional differences, and there are three genera of differentially dominant archaea in the archaea. In summary, significant differences were observed in the physicochemical indexes of bacterial and archaeal abundance across all five samples. These differences led to variations in both the content and composition of volatile constituents.

LED blue light enhances the accumulation and synthesis of steroidal alkaloids in Fritillaria unibracteata Hsiao et K. C. Hsia in vitro

The unique light environment of alpine regions exerts significant influences on the growth, development, and metabolism of alpine plants, with light quality being a fundamental component of light conditions. Varied light qualities manifest diverse effects on plant physiology and function. In order to investigate the impact of light quality on F. unibracteata, this study conducted a comparative analysis of six distinct light quality treatments on the growth, development, stress tolerance, and bioactive compound content of isolated seedlings, and to determine the biomass, physiological parameters, and concentrations of medicinal constituents. It was showed that the blue light treatment was beneficial to F. unibracteata to maintain stable plant growth and increase the total alkaloid content. Furthermore, we explored the effects of blue light treatment on the growth and major medicinal components of F. unibracteata using transcriptome sequencing technology. Through DEGs analysis, we explain the mechanism by which F. unibracteata responds to blue light and that blue light promotes alkaloid accumulation by up-regulating the MEP pathway in the steroidal alkaloid synthesis pathway. These findings suggest that optimizing light conditions can regulate F. unibracteata growth, development, and active ingredient content, laying the groundwork for potential large-scale production.

Major food constituents influence the antibacterial activity of vanillin immobilized onto silicon microparticles against Escherichia coli

Antimicrobial filtration materials based on essential oil components (EOCs) immobilized onto silicon oxide particles have been found effective for nonthermal stabilization of liquid foods (i.e., beer, juice, wine, and etc.). However, their antimicrobial efficiency depends on the food matrix. The present work aimed to assess the effect of the major constituents of liquid food matrices on the antimicrobial activity of vanillin immobilized onto silica microparticles. Silicon oxide particles were functionalized with vanillin and characterized. The maximum tolerated concentrations of different food major constituents (i.e., proteins, lipids, carbohydrates, organic acids, alcohols and minerals) were determined against Escherichia coli K12. The results showed that organic acid and alcohol had synergetic effects on vanillin-functionalized particles, and the addition of proteins, lipids or some carbohydrates inhibited their antimicrobial activity. No effects on microbial counts were found for mineral salts. The dual combinations between the synergistic and nonsynergistic food constituents showed improved antimicrobial activity compared to single compounds. The data confirmed previous in vitro experiments and could be used to predict the antimicrobial activity of the filtration system when treating real liquid food matrices.

Is replacing missing values of PM2.5 constituents with estimates using machine learning better for source apportionment than exclusion or median replacement?

East Asian countries have been conducting source apportionment of fine particulate matter (PM2.5) by applying positive matrix factorization (PMF) to hourly constituent concentrations. However, some of the constituent data from the supersites in South Korea was missing due to instrument maintenance and calibration. Conventional preprocessing of missing values, such as exclusion or median replacement, causes biases in the estimated source contributions by changing the PMF input. Machine learning (ML) can estimate the missing values by training on constituent data, meteorological data, and gaseous pollutants. Complete data from the Seoul Supersite in 2018 was taken, and a random 20% was set as missing. PMF was performed by replacing missing values with estimates. Percent errors of the source contributions were calculated compared to those estimated from complete data. Missing values were estimated using a random forest analysis. Estimation accuracy (r2) was as high as 0.874 for missing carbon species and low at 0.631 when ionic species and trace elements were missing. For the seven highest contributing sources, replacing the missing values of carbon species with estimates minimized the percent errors to 2.0% on average. However, replacing the missing values of the other chemical species with estimates increased the percent errors to more than 9.7% on average. Percent errors were maximal at 37% on average when missing values of ionic species and trace elements were replaced with estimates. Missing values, except for carbon species, need to be excluded. This approach reduced the percent errors to 7.4% on average, which was lower than those due to median replacement. Our results show that reducing the biases in source apportionment is possible by replacing the missing values of carbon species with estimates. To improve the biases due to missing values of the other chemical species, the estimation accuracy of the ML needs to be improved.