Malate Research Articles

Enhanced production of gamma‐aminobutyric acid in fermented carrot juice by utilizing pectin hydrolysate derived from pomegranate waste

AbstractIn this study, a functional fermented beverage enriched with gamma‐aminobutyric acid (GABA) was produced. To achieve this, the prebiotic abilities of pectin obtained from pomegranate peel and its enzymatic hydrolysates were evaluated. Additionally, a functional fermented beverage enriched with GABA was produced by fermenting carrot juice with pectin hydrolysates. First, pectin was obtained at a yield of 8.91% from pomegranate peels. Pectinase‐catalyzed hydrolysis of the obtained pectin was applied using different enzyme concentrations and hydrolysis times, and the effect of these hydrolysates on the growth of Levilactobacillus brevis was determined. Although the Fourier transform infrared (FT‐IR) spectra of the resulting hydrolysates were similar, their degree of esterification compared to that of pectin was statistically different (p < .05). Considering the viability analysis and GABA production of L. brevis in the liquid medium supplemented with pectin or its hydrolysate, the hydrolysate obtained by treatment with 400 μL enzyme for 2 h and having a high glucose content (216.80 mg/100 g) was selected for application in fermented carrot juice. During fermentation (24, 48, and 72 h), a remarkable change was observed, especially in the amounts of lactic acid and malic acid, while the amount of GABA in carrot juice varied between 25 and 46 mg/mL and increased with the increase in hydrolysate concentration. It was observed that the total phenolic content and antioxidant activity of carrot juice were highly affected by the hydrolysate concentration. This study demonstrated that pectin hydrolysate obtained from food waste could be a potential prebiotic and could be used in the production of a functional beverage with improved GABA content.

Effect of Storage Conditions on the Volatilome, Biochemical Composition and Quality of Golden Delicious and Red Delicious Apple (Malus domestica) Varieties.

The effects of normal (NA) and controlled atmosphere (CA) storage and postharvest treatment with 1-methylcyclopropene (1-MCP) before CA storage for 5 months on the volatilome, biochemical composition and quality of 'Golden Delicious' (GD) and 'Red Delicious' (RD) apples were studied. Apples stored under NA and CA maintained and 1-MCP treatment increased firmness in both cultivars. NA storage resulted in a decrease of glucose, sucrose and fructose levels in both cultivars. When compared to CA storage, 1-MCP treatment caused a more significant decrease in sucrose levels and an increase in glucose levels. Additionally, 1-MCP-treated apples exhibited a significant decrease in malic acid content for both cultivars. All storage conditions led to significant changes in the abundance and composition of the volatilome in both cultivars. GD and RD apples responded differently to 1-MCP treatment compared to CA storage; higher abundance of hexanoate esters and (E,E)-α-farnesene was observed in RD apples treated with 1-MCP. While 1-MCP was effective in reducing (E,E)-α-farnesene abundance in GD apples, its impact on RD apples was more limited. However, for both cultivars, all storage conditions resulted in lower levels of 2-methylbutyl acetate, butyl acetate and hexyl acetate. The effectiveness of 1-MCP is cultivar dependent, with GD showing better results than RD.

Ratio-fluorescence sensor based on carbon dots and PtRu/CN nanozyme for efficient detection of melatonin in tablet

The identification and quantification of melatonin (MT) are crucial for early diagnosis of disorders associated with circadian rhythm disruption. Herein, novel blue-emissive carbon dots (BCDs) were synthesized through an improved hydrothermal treatment using serine and malic acid as reductant and carbon source. The excellent optical properties of the as-obtained BCDs were used for ratiometric sensing by strategically constructing a MT sensing system integrating BCDs with C3N4 nanosheets loaded with platinum/ruthenium nanoparticles (PtRu/CN). In this system, H2O2 activated the peroxidase-like activity of PtRu/CN to generate •OH and 1O2 for oxidizing the colorless o-phenylenediamine (OPD) into yellow 2,3-diaminophenazine (DAP) with fluorescence emission at 565 nm. Concurrently, the fluorescence emission of BCDs at 439 nm was quenched by the generated DAP via the static quenching and inner filter effect (IFE) process. However, MT rapidly scavenged the generated free radicals to reverse the ratio fluorescence signal. The developed BCDs/PtRu/CN/OPD/H2O2 sensing platform enabled quantitative analysis of MT at concentrations ranging from 0.06 to 600 μmol/L with a low detection limit of 23.56 nmol/L. Moreover, smartphone-based RGB sensing of MT was successfully developed for rapid visualization and portable processing. More broadly, novel insights into the preparation of carbon dots with sensitive fluorescence sensing properties were presented, promising for future considerations.

Persistent Room‐Temperature Phosphorescent Organohydrogels Based on Nonaromatic Luminogens Crosslinked by Hydrogen Bonds

AbstractThe development of persistent room‐temperature phosphorescent (pRTP) hydrogels is important for the practical applications of organic phosphors. Unfortunately, the phosphorescence emission of nontraditional luminogens (NTLs) can be strongly quenched by water in hydrogel networks. Herein, a series of pRTP organohydrogels based on NTLs are prepared by dissolving poly(vinyl alcohol) (PVA), biuret (BIU) and poly(maleic acid) (PMAc) (or other nonaromatic macromolecular acids) in a glycerol/water mixed solvent, followed by a simple freezing‐thawing treatment. Very impressively, the organohydrogel exhibits remarkable excitation‐dependent and metal cation‐responsive phosphorescence with a maximum lifetime up to 782.8 ms at ambient conditions. Moreover, the organohydrogels treated with metal cations also have excitation‐dependent phosphorescence. Multidimensional information encryption can be achieved by simply printing solutions of metal cations onto the gel surface and switching the irradiation lights, or using gel blocks prepared with different macromolecular acids. Structural characterizations, mechanical tests, and comparative studies prove that hydrogen bonding between BIU and macromolecular chains leads to rigidification of molecular conformations and the cooperative effect of the components leads to the pRTP of the organohydrogels. This work provides a reliable strategy for the preparation of nonaromatic phosphorescent hydrogels with long afterglows and greatly expands the practical applications of phosphorescent materials.

Effect of Chinese bayberry residue on quality of Chinese quinoa (Chenopodium quinoa Willd.) Rice wine

Chinese bayberry residue (CBR) is a by-product of processing, which can be used as an auxiliary material during the processing of quinoa rice wine. In this study, the effects of CBR on the chemical profile, bioactive function, taste traits, and flavor of Chinese quinoa rice wine (CQRW) were investigated. The results showed that adding CBR increased the total phenolics, the total flavonoids, and antioxidant capacity. Malic acid content was the highest in Chinese rice wine (CRW), while the total content of components detected in HPLC-MS/MS was the highest in 10%CBR + CQRW. The CQRW exhibited the highest amino acid content, followed by 20%CBR + CQRW. E-tongue analysis results showed that 10%CBR + CQRW, 20%CBR + CQRW, and CQRW had the closest taste traits. Moreover, GC–MS analysis identified 72 aroma compounds in 10%CBR + CQRW sample, more than other samples. In summary, adding 10% CBR significantly improved the quality of CQRW.

Environment-friendly synthesis of Ti3C2TX MXene by etching and galvanic reactions for Al removal of Ti3AlC2 MAX

Although MXene is acknowledged as next generation two-dimensional (2D) nanomaterials, in general, MXene has been obtained by using hazardous and corrosive etching agents such as HF and HCl. Therefore, in the present study, we report on the environment-friendly synthesis of 2D Ti3C2TX MXene using weak acid H3PO4 as etchant. We compare the Al etching capacity of H3PO4 paired with various metal fluorides (LiF, ZnF2, CuF2) to in-situ form HF. Out of all metal fluoride candidates, CuF2 is the most effective in the etching of Ti3AlC2 MAX not only due to the reaction of F− with Al but also the galvanic replacement of Cu2+ with Al. As a result, Ti3AlC2 MAX is mostly etched using H3PO4/CuF2 within only 4 h reaction and is completely etched in 12 h reaction. After etching, the Cu intercalated between MXene layers is extracted using maleic acid forming a Cu-maleic acid complex to produce exfoliated 2D MXene nanosheets. The exfoliated MXene contains mainly −F, −O, –OH surface terminations and a small portion of −PO4, exhibiting the good aqueous dispersibility.

γ-Aminobutyric acid (GABA) priming alleviates acid-aluminum toxicity to roots of creeping bentgrass via enhancements in antioxidant defense and organic metabolites remodeling.

γ-Aminobutyric acid alleviates acid-aluminum toxicity to roots associated with enhanced antioxidant metabolismas well asaccumulation and transportation of citric and malic acids. Aluminum (Al) toxicity has become the main limiting factor for crop growth and development in acidic soils and is further being aggravated worldwide due to continuous industrial pollution. The current study was designed to examine effects of GABA priming on alleviating acid-Al toxicity in terms of root growth, antioxidant defense, citrate and malate metabolisms, and extensive metabolites remodeling in roots under acidic conditions. Thirty-seven-day-old creeping bentgrass (Agrostis stolonifera) plants were used as test materials. Roots priming with or without 0.5mM GABA for 3days were cultivated in standard nutrient solution for 15days as control or subjected to nutrient solution containing 5mM AlCl3·6H2O for 15days as acid-Al stress treatment. Roots were sampled for determinations of root characteristics, physiological andbiochemical parameters, and metabolomics. GABA priming significantly alleviated acid-Al-induced root growth inhibition and oxidative damage, despite it promoted the accumulation of Al in roots. Analysis of metabolomics showed that GABA priming significantly increased accumulations of organic acids, amino acids, carbohydrates, and other metabolites in roots under acid-Al stress. In addition, GABA priming also significantly up-regulated key genes related to accumulation and transportation ofmalic and citric acids in roots under acid-Al stress. GABA-regulated metabolites participated in tricarboxylic acid cycle, GABA shunt, antioxidant defense system, and lipid metabolism, which played positive roles in reactive oxygen species scavenging, energy conversion, osmotic adjustment, and Al ion chelation in roots.

Hydrophilization and Functionalization of Fullerene C60 with Maleic Acid Copolymers by Forming a Non-Covalent Complex.

In this study, we report an easy approach for the production of aqueous dispersions of C60 fullerene with good stability. Maleic acid copolymers, poly(styrene-alt-maleic acid) (SM), poly(N-vinyl-2-pyrrolidone-alt-maleic acid) (VM) and poly(ethylene-alt-maleic acid) (EM) were used to stabilize C60 fullerene molecules in an aqueous environment by forming non-covalent complexes. Polymer conjugates were prepared by mixing a solution of fullerene in N-methylpyrrolidone (NMP) with an aqueous solution of the copolymer, followed by exhaustive dialysis against water. The molar ratios of maleic acid residues in the copolymer and C60 were 5/1 for SM and VM and 10/1 for EM. The volume ratio of NMP and water used was 1:1.2-1.6. Water-soluble complexes (composites) dried lyophilically retained solubility in NMP and water but were practically insoluble in non-polar solvents. The optical and physical properties of the preparations were characterized by UV-Vis spectroscopy, FTIR, DLS, TGA and XPS. The average diameter of the composites in water was 120-200 nm, and the ξ-potential ranged from -16 to -20 mV. The bactericidal properties of the obtained nanostructures were studied. Toxic reagents and time-consuming procedures were not used in the preparation of water-soluble C60 nanocomposites stabilized by the proposed copolymers.

A Snapshot, Using a Multi-Omic Approach, of the Metabolic Cross-Talk and the Dynamics of the Resident Microbiota in Ripening Cheese Inoculated with Listeria innocua.

Raw milk cheeses harbor complex microbial communities. Some of these microorganisms are technologically essential, but undesirable microorganisms can also be present. While most of the microbial dynamics and cross-talking studies involving interaction between food-derived bacteria have been carried out on agar plates in laboratory-controlled conditions, the present study evaluated the modulation of the resident microbiota and the changes of metabolite production directly in ripening raw milk cheese inoculated with Listeria innocua strains. Using a proxy of the pathogenic Listeria monocytogenes, we aimed to establish the key microbiota players and chemical signals that characterize Latteria raw milk cheese over 60 days of ripening time. The microbiota of both the control and Listeria-inoculated cheeses was analyzed using 16S rRNA targeted amplicon sequencing, while direct analysis in real time mass spectrometry (DART-HRMS) was applied to investigate the differences in the metabolic profiles of the cheeses. The diversity analysis showed the same microbial diversity trend in both the control cheese and the inoculated cheese, while the taxonomic analysis highlighted the most representative genera of bacteria in both the control and inoculated cheese: Lactobacillus and Streptococcus. On the other hand, the metabolic fingerprints revealed that the complex interactions between resident microbiota and L. innocua were governed by continuously changing chemical signals. Changes in the amounts of small organic acids, hydroxyl fatty acids, and antimicrobial compounds, including pyroglutamic acid, hydroxy-isocaproic acid, malic acid, phenyllactic acid, and lactic acid, were observed over time in the L. innocua-inoculated cheese. In cheese that was inoculated with L. innocua, Streptococcus was significantly correlated with the volatile compounds carboxylbenzaldheyde and cyclohexanecarboxylic acid, while Lactobacillus was positively correlated with some volatile and flavor compounds (cyclohexanecarboxylic acid, pyroxidal acid, aminobenzoic acid, and vanillic acid). Therefore, we determined the metabolic markers that characterize a raw milk cheese inoculated with L. innocua, the changes in these markers with the ripening time, and the positive correlation of flavor and volatile compounds with the resident microbiota. This multi-omics approach could suggest innovative food safety strategies based on the enhanced management of undesirable microorganisms by means of strain selection in raw matrices and the addition of specific antimicrobial metabolites to prevent the growth of undesirable microorganisms.

Dissolving Chitin by Novel Deep Eutectic Solvents for Effectively Enzymatic Hydrolysis.

Chitin is the most productive nitrogen-containing polysaccharide in nature with immense potential for transforming into a range of chemicals. However, its dense crystal structure poses a challenge for depolymerization, limiting its applications. To overcome these challenges, a novel series of deep eutectic solvents (DESs) based on benzyltrimethylammonium chloride (TMBAC) as the hydrogen bond acceptor was developed. These TMBAC-based DESs, in combination with lactic acid, oxalic acid, and malic acid as the hydrogen bond donor demonstrated efficient chitin dissolution, achieving a solubility of up to 12% and an 88% recovery rate of regenerated chitin. The regenerated chitin was characterized using XRD, FT-IR, SEM, and 13C CP-MAS NMR, which indicated the preservation of chitin's chemical structure, a significant decrease in crystallinity, and a reduction in the molecular weight. Furthermore, the enzymatic hydrolysis efficiency of chitin was nearly doubled after treatment with TMBAC-based DESs, surpassing the effectiveness of untreated chitin. This approach holds promise for facilitating subsequent transformation and utilization of chitin.

Orange passion fruit (Passiflora caerulea L.) as a new raw material for acetic fermentation: evaluation of organic acids and phenolic profile, in vitro digestion, and biological activities.

This study evaluated for the first time the potential of orange passion fruit as a base for alcoholic and acetic fermentations, with a view to assessing its profile of organic acids and polyphenols, in vitro digestion, and biological activities. In terms of aliphatic organic acids, malic acid was the majority in the wine (3.19 g L-1), while in the vinegar, it was acetic acid (46.84 g L-1). 3,4-Dihydroxybenzoic acid (3,4-DHB) was the major phenolic compound in the wine and vinegar samples (3443.93 and 2980.00 μg L-1, respectively). After the in vitro gastrointestinal simulation stage, the wine showed high bioaccessibility for the compounds sinipaldehyde (82.97%) and 2,4-dihydroxybenzoic acid (2,4-DHBA, 81.27%), while the vinegar exhibited high bioaccessibility for sinipaldehyde (89.39%). Through multivariate analysis, it was observed that 3,4-DHB was highly concentrated in the different digested fractions obtained from the wine. In contrast, in the vinegar, the stability of isorahmenetin and Quercetin 3-o-rhamnoside was observed during the in vitro digestion simulation. Lastly, the vinegar stood out for its inhibition rates of α-amylase (23.93%), α-glucoside (18.34%), and angiotensin-converting enzyme (10.92%). In addition, the vinegar had an inhibitory effect on the pathogenic microorganisms Salmonella enteritidis, Escherichia coli, and Listeria monocytogenes. Orange passion fruit has proved to be a promising raw material for the development of fermented beverages. Therefore, this study provides an unprecedented perspective on the use and valorization of orange passion fruit, contributing significantly to the advancement of knowledge about fermented products and the associated nutritional and functional possibilities. © 2024 Society of Chemical Industry.

Targeted Metabolomics of Tissue and Plasma Identifies Biomarkers in Mice with NOTCH1-Dependent T-Cell Acute Lymphoblastic Leukemia.

While the genomics era has allowed remarkable advances in understanding the mechanisms driving the biology and pathogenesis of numerous blood cancers, including acute lymphoblastic leukemia (ALL), metabolic studies are still lagging, especially regarding how the metabolism differs between healthy and diseased individuals. T-cell ALL (T-ALL) is an aggressive hematological neoplasm deriving from the malignant transformation of T-cell progenitors characterized by frequent NOTCH1 pathway activation. The aim of our study was to characterize tumor and plasma metabolomes during T-ALL development using a NOTCH1-induced murine T-ALL model (ΔE-NOTCH1). In tissue, we found a significant metabolic shift with leukemia development, as metabolites linked to glycolysis (lactic acid) and Tricarboxylic acid cycle replenishment (succinic and malic acids) were elevated in NOTCH1 tumors, while metabolites associated with lipid oxidation (e.g., carnitine) as well as purine and pyrimidine metabolism were elevated in normal thymic tissue. Glycine, serine, and threonine metabolism, glutathione metabolism, as well as valine, leucine, and isoleucine biosynthesis were enriched pathways in tumor tissue. Phenylalanine and tyrosine metabolism was highly enriched in plasma from leukemia-bearing mice compared to healthy mice. Further, we identified a metabolic signature consisting of glycine, alanine, proline, 3-hydroxybutyrate, and glutamic acid as potential biomarkers for leukemia progression in plasma. Hopefully, the metabolic differences detected in our leukemia model will apply to humans and contribute to the development of metabolism-oriented therapeutic approaches.

Enhanced Mineralization of Organic Pollutants through Atomic Hydrogen-Mediated Alternative Transformation Pathways.

Electrocatalytic hydrogen atom-hydroxyl radical (H*-·OH) redox system is a promising approach for contaminant removal and mineralization. However, its working mechanism, especially the effect of H*, remains unclear, hindering its practical application. Herein, we constructed an electrochemical reactor equipped with our self-made Pd-loaded Ti/TiO2 nanotube cathode and a commercial boron-doped diamond anode. After fulfilling the electrode characterization and free radical detection, we employed coumarin and 7-azido-4-methylcoumarin as probes to confirm the participation of H* in the transformation of organic compounds. A comprehensive study on the degradation kinetics, reaction, and mineralization mechanisms using benzoic acid (BA) and 4-chlorophenol (4-CP) as model compounds was further conducted. The rate constants and total organic carbon removal of BA and 4-CP in the redox system increased compared with those of the individual oxidation and reduction processes. Theoretical calculations demonstrate that H* opens up alternative pathways for BA and 4-CP ring cleavage, forming quinones as reactive intermediates. Furthermore, H* facilitates the mineralization of the typical intermediates, maleic acid and fumaric acid, through C=C bond addition and H-abstraction from the 1,1-diol structure. The presence of H* provides alternative pathways for pollutant transformation, consequently reducing the treatment duration.

BomMDH1 regulates malate-mediated oxidative stress in tobacco BY-2 suspension cells

Programmed cell death (PCD) is a genetically regulated process of cell suicide essential for plant development. The ‘malate valve’ is a mechanism that ensures redox balance across different subcellular compartments. In broccoli, the BomMDH1 gene encodes malate dehydrogenase in mitochondria, a critical enzyme in the ‘malate circulation’ pathway. This study investigates the functional role of BomMDH1 in malate (MA)-induced apoptosis in bright yellow-2 (BY-2) suspension cells. Findings revealed that transgenic cells overexpressing BomMDH1 showed enhanced viability under MA-induced oxidative stress compared to wild-type (WT) cells. Overexpression of BomMDH1 also reduced levels of reactive oxygen species (ROS), hydrogen peroxide (H2O2), and malondialdehyde (MDA), while increasing the expression of antioxidant enzyme genes such as NtAPX, NtAOX1a, NtSOD, and NtMDHAR. Additionally, treatment with salicylhydroxamic acid (SHAM), a characteristic inhibitor of mitochondrial respiration, further improved the anti-apoptotic activity of BY-2 cells. Overall, these results highlighted the function of the BomMDH1 gene and the potential of SHAM treatment in mitigating oxidative stress in BY-2 suspension cells.

Enhancing Lettuce Drought Tolerance: The Role of Organic Acids in Photosynthesis and Oxidative Defense

The aim of this study was to investigate the effects of maleic acid (MA), salicylic acid (SA), and citric acid (CA) on alleviating the drought stress of a lettuce (Lactuca sativa L.) hydroponic culture. The effect of these organic acids was tested under stress conditions induced by polyethene glycol (PEG 6000) at 5% and 7.5% concentrations. Drought stress reduced the fresh and dry matter yields of plants. The acid treatment caused increasing tendencies in the fresh weight yield:control (SA, MA), PEG 7.5% (SA, MA, CA)) and dry weight yield (control (SA, MA), PEG 5% (MA), PEG 7.5% (SA, MA)). The acid treatment also enhanced the nutrient uptake of stressed plants: SA: N (PEG 7.5%), K (PEG 5 and 7.5%); MA: N, P, K, Ca (PEG 5 and 7.5%). This work found that chlorophyll a and b amounts did not change under applied experimental conditions. Most parameters of chlorophyll fluorescence did not depend on either the level of applied water stress (PEG level) or the type of spraying. Drought stress increased leaf superoxide anion (O2•−) and malondialdehyde (MDA) levels but decreased H2O2. Proline (Pro) and phenolic compounds (TFC), including flavonols (Fla), accumulated more in stressed plants. Drought stress also affected the chlorophyll fluorescence. Our results suggest that acids can improve plant tolerance to drought stress by boosting the antioxidant defence system and reducing the oxidative damage caused by reactive oxygen species.

Effects of kinds of additives on fermentation quality, nutrient content, aerobic stability, and microbial community of the mixed silage of king grass and rice straw.

To investigate the effects of kinds of additives on silage quality, the mixture of king grass and rice straw was ensiled with addition of sucrose, citric acid and malic acid at the levels of 0, 1 and 2%, being blank control (CK), citric acid groups (CA1, CA2), malic acid groups (MA1, MA2), citric acid + malic acid groups (CM1, CM2), sucrose groups (SU1, SU2), mainly focusing on fermentation quality, nutrient content, aerobic stability and microbial community of the silages. The results showed that the addition of sucrose decreased (p < 0.05) pH and increased the content of water soluble carbohydrate (p < 0.05). The sucrose groups and mixed acid groups also had a lower (p < 0.01) neutral detergent fiber content. The addition of citric acid and the mixed acid increased (p < 0.01) the aerobic stability of the silage, reduced the abundance of Acinetobacter, and the addition of citric acid also increased the abundance of Lactiplantibacillus. It is inferred that citric acid and malic acid could influence fermentation quality by inhibiting harmful bacteria and improve aerobic stability, while sucrose influenced fermentation quality by by promoting the generation of lactic acid. It is suggested that the application of citric acid, malic acid and sucrose would achieve an improvement effect on fermentation quality of the mixed silage.

Residue behavior and quality influence of tolfenpyrad and cyromazine in cowpea during simulated household washing process

Cowpea, a typical vegetable characterized by a consistent growth and harvest period, often accumulates high pesticide residues in pods. The household washing process has the potential to impact both pesticide residue and the quality of cowpea pods. This study investigated the behavior of tolfenpyrad and cyromazine in cowpea pods using in situ mass spectrometry imaging, analyze changes in nutrients, and explore typical metabolite alterations following the washing process. Both tolfenpyrad and cyromazine levels on the surface of the cowpea were significantly reduced after the washing process, although cyromazine distributed inside the cowpea remained at a high level. Immersing cowpeas in 2% NaHCO3 for 30 min and a 3 min tap-water rinse resulted in the removal of 72% and 58% of tolfenpyrad, 66% and 50% of cyromazine, respectively. Importantly, a 3 min tap-water rinse did not impact nutrient content, while other 30 min immersions led to a reduction in typical nutritional factors. Furthermore, the levels of typical metabolites such as tamarix, quercetin, and aspartic acid were down-regulated, while malic acid, glucose, and ascorbic acid were up-regulated in cowpea after pesticide immersion. The concentrations of all six metabolites in cowpea decreased after the washing procedure.

NaCl Modifies Biochemical Traits in Bacterial Endophytes Isolated from Halophytes: Towards Salinity Stress Mitigation Using Consortia.

Bacterial endophytes (120) were isolated from six halophytes (Distichlis spicata, Cynodon dactylon, Eragrostis obtusiflora, Suaeda torreyana, Kochia scoparia, and Baccharis salicifolia). These halophiles were molecularly identified and characterized with or without NaCl conditions. Characterization was based on tests such as indole acetic acid (IAA), exopolysaccharides (EPS), and siderophores (SID) production; solubilization of phosphate (P), potassium (K), zinc (Zn), and manganese (Mn); mineralization of phytate; enzymatic activity (acid and alkaline phosphatase, phytases, xylanases, and chitinases) and the mineralization/solubilization mechanisms involved (organic acids and sugars). Moreover, compatibility among bacteria was assessed. Eleven halophiles were characterized as highly tolerant to NaCl (2.5 M). The bacteria isolated were all different from each other. Two belonged to Bacillus velezensis and one to B. pumilus while the rest of bacteria were identified up to the genus level as belonging to Bacillus, Halobacillus, Halomonas, Pseudomonas, Nesterenkonia, and three strains of Oceanobacillus. The biochemical responses of nutrient solubilization and enzymatic activity were different between bacteria and were influenced by the presence of NaCl. Organic acids were involved in P mineralization and nutrient solubilization. Tartaric acid was common in the solubilization of P, Zn, and K. Maleic and vanillic acid were only detected in Zn and K solubilization, respectively. Furthermore, sugars appeared to be involved in the solubilization of nutrients; fructose was detected in the solubilization tests. Therefore, these biochemical bacterial characteristics should be corroborated in vivo and tested as a consortium to mitigate saline stress in glycophytes under a global climate change scheme that threatens to exacerbate soil salinity.

Optimization of an Ultrasound-Assisted Extraction Technique and the Effectiveness of the Sunscreen Components Isolated from Bletilla striata.

Bletilla striata is the dried tuber of B. striata (Thund.) Reichb.f., which has antibacterial, anti-inflammatory, anti-tumor, antioxidant and wound healing effects. Traditionally, it has been used for hemostasis therapy, as well as to treat sores, swelling and chapped skin. In this study, we used the ultraviolet (UV) absorbance rate of B. striata extracts as the index, and the extraction was varied with respect to the solid-liquid ratio, ethanol concentration, ultrasonic time and temperature in order to optimize the extraction process for its sunscreen components. The main compounds in the sunscreen ingredients of Baiji (B. striata) were analyzed using ultra-high-performance liquid chromatography combined with quadrupole time-of-flight tandem mass spectrometry. The sunscreen properties were subsequently evaluated in vitro using the 3M tape method. The results show that the optimal extraction conditions for the sunscreen components of B. striata were a solid-liquid ratio of 1:40 (g/mL), an ethanol concentration of 50%, an ultrasonic time of 50 min and a temperature of 60 °C. A power of 100 W and an ultrasonic frequency of 40 Hz were used throughout the experiments. Under these optimized conditions, the UV absorption rate of the isolated sunscreen components in the UVB region reached 84.38%, and the RSD was 0.11%. Eighteen compounds were identified, including eleven 2-isobutyl malic acid glucose oxybenzyl esters, four phenanthrenes, two bibenzyl and one α-isobutylmalic acid. An evaluation of the sunscreen properties showed that the average UVB absorption values for the sunscreen samples from different batches of B. striata ranged from 0.727 to 1.201. The sunscreen ingredients of the extracts from B. striata had a good UV absorption capacity in the UVB area, and they were effective in their sunscreen effects under medium-intensity sunlight. Therefore, this study will be an experimental reference for the extraction of sunscreen ingredients from the B. striata plant, and it provides evidence for the future development of B. striata as a candidate cosmetic raw material with UVB protection properties.

Soil conditioner improves soil properties, regulates microbial communities, and increases yield and quality of Uncaria rhynchophylla

Uncaria rhynchophylla is an important traditional herbal medicine in China, and the yield and quality of Uncaria rhynchophylla can be improved by suitable soil conditioners because of changing the soil properties. In this paper, Uncaria rhynchophylla associated alkaloids and soil microbial communities were investigated. The field experiment was set up with the following control group: (M1, no soil conditioner) and different soil conditioner treatment groups (M2, biomass ash; M3, water retention agent; M4, biochar; M5, lime powder and M6, malic acid). The results showed that M2 significantly increased the fresh and dry weight and the contents of isorhynchophylline, corynoxeine, isocorynoxeine, and total alkaloids. Acidobacteria, Proteobacteria, Actinobacteria, and Chloroflexi were major bacterial phyla. Correlation analysis showed that fresh and dry weight was significantly positively correlated with Acidobacteria, while alkali-hydrolyzable nitrogen, phosphatase activity, fresh and dry weight, corynoxeine, and isocorynoxeine were significantly negatively correlated with Chloroflexi. The application of soil conditioner M2 increased the abundance of Acidobacteria and decreased the abundance of Chloroflexi, which contributed to improving the soil nutrient content, yield, and quality of Uncaria rhynchophylla. In summary, biomass ash may be a better choice of soil conditioner in Uncaria rhynchophylla growing areas.