Anaerobic digestion of tobacco stalk: biomethane production performance and kinetic analysis

Tobacco stalk, a common agricultural waste derived from the harvest of tobacco, caused serious environmental pollution in China. In this study, the performance of biomethane production and characteristics of four varieties of tobacco stalk were investigated for the first time. The results showed that the highest cumulative methane yield of 130.2 mL/g-VS was obtained from Nicotiana tabacum L., Yunyan114, which had lower lignin content than other varieties of tobacco stalk. Moreover, different kinetic models were used to describe the biomethane production process, and it was found that the modified Gompertz model was more suitable to simulate the anaerobic digestion (AD) of tobacco stalk. The findings of this study not only showed a feasible method for minimizing the pollution issues of tobacco stalk waste but also gave fundamental information for future AD application.

Report: Pharmacognostic and physicochemical screening of Euphorbia nivulia Buch.-Ham

Euphorbia nivulia Buch.-Ham. (Euphorbiaceae) is commonly known as Indian Spurge Tree in English, and "Saj Thor" or "Jhanami booti" in local language. The plant is used traditionally in the treatment of various diseases like inflammation, fever, worm infection, asthma, cough, wounds and diabetes. In current study fresh as well as dried aerial parts of the plant and cut sections were examined, both macroscopically and microscopically. The study also deals with fluorescence analysis and phytochemical characteristics and other WHO recommended methods for standardization. WHO guidelines on quality control for medicinal plants materials were used for pharmacognostical evaluation of E. nivulia, phytochemical screening helps in determining the predominant classes of active constituents responsible for the activity. The present work will be helpful in identification of the fresh and dried samples of aerial parts pharmacognostically and anatomically. These studies will serve as a reference for correct identification and may be helpful in checking any type of adulteration. These observations will also help in differentiating this species from closely related species of the same genus and family.

[Distribution and accumulation of inorganic elements in Ligusticum chuanxiong]

Aiming at the phenomenon of heavy metal Cd exceeding the standard of Chuanxiong medicinal materials,the accumulation of 12 inorganic elements,including heavy metals,in Ligusticum chuanxiong was studied in this paper. It was found that the contents and distribution of most inorganic elements in the stems and leaves of L. chuanxiong were higher than those in the rhizomes at seedling and shooting stages. The content of most elements in rhizome reached the highest at harvest stage,and the distribution ratio of some elements in rhizome was higher than that in stem and leaf at harvest stage. But rhizome,stem and leaf of L. chuanxiong have relatively stable absorption capacity and enrichment effect on different elements,and are less affected by growth period and position. Rhizomes and stems and leaves of L. chuanxiong were enriched with Cd,and stems and leaves also accumulated Pb at seedling stage and stem stage. The absorption capacity of Pb in stems and leaves of L. chuanxiong was higher than that of rhizomes,and the ability of absorbing Cd was less than that of rhizomes at harvest time. The total uptake of Cd and Pb by L. chuanxiong decreased with the prolongation of growth time,but the proportion of Cd and Pb in rhizome increased,so that the content of Cd and Pb increased with the prolongation of growth time.

Phenolic Profile and Bioactive Properties of Carissa macrocarpa (Eckl.) A.DC.: An In Vitro Comparative Study between Leaves, Stems, and Flowers

The present work aimed to characterize leaves, stems, and flowers of Carissa macrocarpa (Eckl.) A.DC., by performing an analysis of the phenolic compounds by HPLC-DAD/ESI-MS, correlating them with bioactive properties, such as antioxidant, anti-inflammatory, cytotoxic, and antimicrobial activities. Thirty polyphenols were identified in the hydroethanolic extract, including phenolic acids, flavan-3-ols, and flavonol glycosides derivatives (which presented the highest number of identified compounds). However, flavan-3-ols showed the highest concentration in stems (mainly owing to the presence of dimers, trimmers, and tetramers of type B (epi)catechin). Leaves were distinguished by their high antioxidant and anti-inflammatory activities, as well as their bactericidal effect against E. coli, while stems presented a higher cytotoxic activity and bactericidal effect against Gram-positive bacteria. Moreover, a high correlation between the studied bioactivities and the presence of phenolic compounds was also verified. The obtained results bring added value to the studied plant species.

Methanol stem bark extract of Adansonia digitata ameliorates chronic unpredictable mild stress-induced depression-like behavior: Involvement of the HPA axis, BDNF, and stress biomarkers pathways

Background Adansonia digitata L. (Malvaceae) is used locally in the management of depressive illnesses, and its antidepressant-like effect has been previously reported. The present study was aimed at determining the effect of the methanol extract of the stem bark of A. digitata (MEAD) on chronic unpredictable mild stress (CUMS) and the possible mechanism responsible for its antidepressant activity. Methods Acute toxicity of MEAD was determined using the OECD guideline 420. The CUMS model was used to induce depression, and behavioral tests such as sucrose preference test (SPT), open field test (OFT), novel-object recognition test (NORT), and tail suspension test (TST) were carried out in mice. The concentrations of plasma cortisol and brain-derived neurotrophic factor (BDNF) protein in the brain were assessed using enzyme-linked immunosorbent assay kits. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were assessed using colorimetric methods. Results The LD50 was established to be ≥5000 mg/kg. On CUMS-induced depression, MEAD significantly (p ≤ 0.05) and dose dependently reversed the weight loss, increased the line-crossing activity in OFT, increased sucrose consumption in SPT, decreased the duration of immobility in TST, and increased the novelty exploration time in NORT. The MEAD extract significantly (p ≤ 0.05) and dose dependently increased the levels of BDNF, decreased the levels of plasma cortisol, increased the levels of total SOD activity, and decreased the levels of plasma MDA. Conclusion Our findings show that MEAD ameliorates CUMS-induced depressive-like behavior and its effect is possibly mediated via the neuroendocrine, neurotrophic, and oxidative stress pathways.

Salicylate and Procyanidin-Rich Stem Extracts of Gaultheria procumbens L. Inhibit Pro-Inflammatory Enzymes and Suppress Pro-Inflammatory and Pro-Oxidant Functions of Human Neutrophils Ex Vivo

Salicylate-rich plants are an attractive alternative to synthetic anti-inflammatory drugs due to a better safety profile and the advantage of complementary anti-inflammatory and antioxidant effects of the co-occurring non-salicylate phytochemicals. Here, the phytochemical value and biological effects in vitro and ex vivo of the stems of one of such plants, Gaultheria procumbens L., were evaluated. The best extrahent for effective recovery of the active stem molecules was established in comparative studies of five extracts. The UHPLC-PDA-ESI-MS³, HPLC-PDA, and UV-photometric assays revealed that the selected acetone extract (AE) accumulates a rich polyphenolic fraction (35 identified constituents; total content 427.2 mg/g dw), mainly flavanols (catechins and proanthocyanidins; 201.3 mg/g dw) and methyl salicylate glycosides (199.9 mg/g dw). The extract and its model components were effective cyclooxygenase-2, lipoxygenase, and hyaluronidase inhibitors; exhibited strong antioxidant capacity in six non-cellular in vitro models (AE and procyanidins); and also significantly and dose-dependently reduced the levels of reactive oxygen species (ROS), and the release of cytokines (IL-1β, IL-8, TNF-α) and proteinases (elastase-2, metalloproteinase-9) in human neutrophils stimulated ex vivo by lipopolysaccharide (LPS) and N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP). The cellular safety of AE was demonstrated by flow cytometry. The results support the application of the plant in traditional medicine and encourage the use of AE for development of new therapeutic agents.

Non-invasive monitoring of red beet development

Agricultural monitoring is required to enhance crop production, control plant stress, and predict pests and crop infection. Apart from monitoring the external influences, the state of the plant itself must be tracked. However, the modern methods for plant analysis are expensive and require plants processing often in a destructive way. Optical spectroscopy can be used for the non-invasive monitoring requiring no consumables, and little to none sample preparation. In this context, we found that the red beet growth can be monitored by Raman spectroscopy. Our analysis shows that, as plants age, the rate of betalain content increases. This increase makes betalain dominate the whole Raman spectra over other plant components. The dominance of betalain facilitates its use as a molecular marker for plant growth. This finding has implications in the understanding of plant physiology, particularly important for greenhouse growth and the optimization of external conditions such as artificial illumination.

Nitrogen and phosphorus removal from wastewater by sand with wheat straw

Wheat straw amendment to sandy soil has the potential to remove nutrients from wastewater. This study investigated the ability of wheat straw to remove inorganic nitrogen (N) and phosphorus (P) from wastewater when mixed into sand at different rates. Wastewater from a sewage treatment plant was added to sand alone and amended with different wheat straw rates 2.5, 5, 7.5, 10, and 12.5 g wheat straw kg^-1 so that the sand was covered with about 15 cm of wastewater. Leaching was carried out after 4, 8, and 16 days and inorganic N and P were analysed after leaching in both the leachate and sand, as well as N₂O and CO₂ release. In the amended sand, nitrate was about fourfold lower throughout the experiment compared to sand alone. Ammonium was twofold higher than sand alone at 12.5 g straw kg^-1 throughout the experiment and on day 16 also at ≥ 5 g straw kg^-1. Leachate inorganic N concentration was up to 70-fold higher in sand alone than in amended soils irrespective of straw rate. On day 16, P leaching was about threefold lower and P retention was 40% higher in all amended treatments than sand alone. The redox potential in sand alone was higher than with straw amendments. With straw amendment, the release of CO₂ per day was six times higher than with sand alone and increased with straw rates, but very little N₂O and CH₄ was released throughout the experiment. It can be concluded that amendment of sand with wheat straw can remove large proportions of inorganic N and P from wastewater, even at low straw rates. Likely mechanisms for retention are dissimilatory nitrate reduction and subsequent binding of ammonium to straw for N, and binding to the straw and microbial uptake for P.

Kinetic modeling of high-pressure induced inactivation of polyphenol oxidase in sugarcane juice (Saccharum officinarum)

BACKGROUND

Polyphenol oxidase (PPO) is the main enzyme in sugarcane juice associated with rapid browning and degradation of organoleptic properties. High-pressure processing (HPP) (300-600 MPa) of sugarcane juice in combination with moderate temperatures (30-60 °C) for different processing times (10-25 min) has shown promising results in minimizing PPO activity while preserving the juice's freshness.

RESULTS

A maximum PPO inactivation of 98% was achieved at 600 MPa/60 °C/25 min, while the corresponding value for thermal treatment at 0.1 MPa/60 °C was only 66%. The nonlinearity in the inactivation data was well described by the Weibull distribution model with a high adjusted R² and reduced χ² values at all levels of pressure and temperature. The PPO inactivation data were fitted at shape parameter, β = 1 (log linear) and β ≠ 1. A refitted Weibull model was used to predict kinetic parameters such as the inactivation rate constants (k), activation energy (E_a ) and activation volume (V_a ), which govern PPO inactivation in HPP-treated sugarcane juice. A secondary kinetic model was formulated to predict the k values as a function of pressure (P) and temperature (T), incorporating E_a and V_a .

CONCLUSIONS

Combined high-pressure and temperature processing has been considered a reliable alternative to conventional heat treatment for inhibiting PPO activity in sugarcane juice. While the isothermal inactivation of PPO followed first-order kinetics, inclusion of high pressure resulted in a strong deviation from log linear kinetics. Identification of suitable kinetic models describing these inactivation processes is expected to aid product development and process control of high-pressure processed sugarcane juice. © 2018 Society of Chemical Industry.

Effects of straw amendment on selenium aging in soils: Mechanism and influential factors

Soil dissolved organic matter (DOM) alters heavy metal availability, but whether straw amendment can manipulate soil selenium (Se) speciation and availability through DOM mineralization remains unclear. In this study, allochthonous maize straw and selenate were incubated together in four different soils for 1 y. The transformation and availability of DOM associated Se (DOM-Se) was investigated during aging. Results indicated that soil solution and soil particle surfaces were dominated by hexavalent hydrophilic acid-bound Se (Hy-Se). The amount of fulvic acid bound Se in soil solution (SOL-FA-Se) was higher than humic acid bound Se in soil solution (SOL-HA-Se), except in krasnozems, and mainly existed as hexavalent Se (Se(VI)). Tetravalent Se (Se(IV)) was the main valence state of FA-Se adsorbed on soil particle surfaces (EX-FA-Se) after 5 w of aging. The proportion of soil-available Se (SOL + EX-Se) decreased with increasing straw rate. However, under an application rate of 7500 kg·hm^-2, soluble Se fraction (SOL-Se) reduction was minimal in acidic soils (18.7%-34.7%), and the organic bound Se fraction (OM-Se) was maximally promoted in alkaline soils (18.2%-39.1%). FA and HON could enhance the availability of Se in the soil solution and on particle surfaces of acidic soil with high organic matter content. While Se incorporation with HA could accelerate the fixation of Se into the solid phase of soil. Three mechanisms were involved in DOM-Se aging: (1) Reduction, ligand adsorption, and inner/outer-sphere complexation associated with the functional groups of straw-derived DOM, including hydroxyls, carboxyl, methyl, and aromatic phenolic compounds; (2) interconnection of EX-FA-Se between non-residual and residual Se pools; and (3) promotion by soil electrical conductivity (EC), clay, OM, and straw application. The dual effect of DOM on Se aging was highly reliant on the characteristics of the materials and soil properties. In conclusion, straw amendment could return selenium in soil and reduce soluble Se loss.

Anti-HIV-1 integrase potency of methylgallate from Alchornea cordifolia using in vitro and in silico approaches

According to the 2018 report of the United Nations Programme on HIV/AIDS (UNAIDS), acquired immune deficiency syndrome (AIDS), a disease caused by the human immunodeficiency virus (HIV), remains a significant public health problem. The non-existence of a cure or effective vaccine for the disease and the associated emergence of resistant viral strains imply an urgent need for the discovery of novel anti-HIV drug candidates. The current study aimed to identify potential anti-retroviral compounds from Alchornea cordifolia. Bioactive compounds were identified using several chromatographic and spectroscopic techniques and subsequently evaluated for cytotoxicity and anti-HIV properties. Molecular modelling studies against HIV-1 integrase (HIV-1 IN) were performed to decipher the mode of action of methylgallate, the most potent compound (IC50 = 3.7 nM) and its analogues from ZINC database. Cytotoxicity assays showed that neither the isolated compounds nor the crude methanolic extract displayed cytotoxicity effects on the HeLa cell line. A strong correlation between the in vitro and in silico results was observed and important HIV-1 IN residues interacting with the different compounds were identified. These current results indicate that methylgallate is the main anti-HIV-1 compound in A. cordifolia stem bark, and could be a potential platform for the development of new HIV-1 IN inhibitors.

Low-quality rice straw forage increases the permeability of mammary epithelial tight junctions in lactating dairy cows

BACKGROUND

It is known that milking frequency and plasma hormones play important roles in regulating mammary permeability. However, it is still not known whether nutritional factors can influence udder permeability.

DESIGN

This study was conducted to investigate mammary epithelial tight-junction permeability in lactating dairy cows fed different forage-based diets. Twenty mid-lactating dairy cows were allocated to ten blocks based on their parity and milk yield and then randomly assigned into rice straw-based diet and alfalfa-based diet groups. Both diets contained 15% corn silage and 55% concentrate (dry matter basis). In terms of forage sources, rice straw-based diets (RS) contained 30% rice straw, whereas alfalfa-based diets (AH) contained 23% alfalfa hay plus 7% Chinese wild rye hay.

RESULTS

The concentrations of Na⁺ , Na⁺ /K⁺ ratio, bovine serum albumin, and plasmin in the milk, the plasma lactose concentration, and the mRNA abundance of BCL2 associated agonist of cell death, phosphatase and tensin homolog, and insulin like growth factor binding protein 5 in the mammary gland were greater in RS-fed cows than in AH-fed animals. Mammary expression of proliferating cell nuclear antigen and occludin was lower in RS-fed cows compared with the AH-fed group. The expressions of growth hormone receptor, claudin-1, -3, -4, and ZO-1 were similar in the two diet groups.

CONCLUSION

The cows fed RS showed higher mammary alveolar permeability, likely due to its effect on proliferation/apoptosis rates of mammary epithelial cells. © 2018 Society of Chemical Industry.

Miscanthus x giganteus Stem Versus Leaf-Derived Lignins Differing in Monolignol Ratio and Linkage

As a renewable, Miscanthus offers numerous advantages such as high photosynthesis activity (as a C₄ plant) and an exceptional CO₂ fixation rate. These properties make Miscanthus very attractive for industrial exploitation, such as lignin generation. In this paper, we present a systematic study analyzing the correlation of the lignin structure with the Miscanthus genotype and plant portion (stem versus leaf). Specifically, the ratio of the three monolignols and corresponding building blocks as well as the linkages formed between the units have been studied. The lignin amount has been determined for M. x giganteus (Gig17, Gig34, Gig35), M. nagara (NagG10), M. sinensis (Sin2), and M. robustus (Rob4) harvested at different time points (September, December, and April). The influence of the Miscanthus genotype and plant component (leaf vs. stem) has been studied to develop corresponding structure-property relationships (i.e., correlations in molecular weight, polydispersity, and decomposition temperature). Lignin isolation was performed using non-catalyzed organosolv pulping and the structure analysis includes compositional analysis, Fourier transform infradred (FTIR), ultraviolet/visible (UV-Vis), hetero-nuclear single quantum correlation nuclear magnetic resonsnce (HSQC-NMR), thermogravimetric analysis (TGA), and pyrolysis gaschromatography/mass spectrometry (GC/MS). Structural differences were found for stem and leaf-derived lignins. Compared to beech wood lignins, Miscanthus lignins possess lower molecular weight and narrow polydispersities (<1.5 Miscanthus vs. >2.5 beech) corresponding to improved homogeneity. In addition to conventional univariate analysis of FTIR spectra, multivariate chemometrics revealed distinct differences for aromatic in-plane deformations of stem versus leaf-derived lignins. These results emphasize the potential of Miscanthus as a low-input resource and a Miscanthus-derived lignin as promising agricultural feedstock.

Automated measurements of greenhouse gases fluxes from tree stems and soils: magnitudes, patterns and drivers

Tree stems exchange CO2, CH4 and N2O with the atmosphere but the magnitudes, patterns and drivers of these greenhouse gas (GHG) fluxes remain poorly understood. Our understanding mainly comes from static-manual measurements, which provide limited information on the temporal variability and magnitude of these fluxes. We measured hourly CO2, CH4 and N2O fluxes at two stem heights and adjacent soils within an upland temperate forest. We analyzed diurnal and seasonal variability of fluxes and biophysical drivers (i.e., temperature, soil moisture, sap flux). Tree stems were a net source of CO2 (3.80 ± 0.18 µmol m-2 s-1; mean ± 95% CI) and CH4 (0.37 ± 0.18 nmol m-2 s-1), but a sink for N2O (-0.016 ± 0.008 nmol m-2 s-1). Time series analysis showed diurnal temporal correlations between these gases with temperature or sap flux for certain days. CO2 and CH4 showed a clear seasonal pattern explained by temperature, soil water content and sap flux. Relationships between stem, soil fluxes and their drivers suggest that CH4 for stem emissions could be partially produced belowground. High-frequency measurements demonstrate that: a) tree stems exchange GHGs with the atmosphere at multiple time scales; and b) are needed to better estimate fluxes magnitudes and understand underlying mechanisms of GHG stem emissions.

Isolation and Purification of Bioactive Compounds from the Stem Bark of Jatropha podagrica

This paper reports the successive isolation and purification of bioactive compounds from the stem bark of Jatropha podagrica, a widely known medicinal plant. The ethyl acetate extract of the stem bark exhibited the strongest antioxidant activity assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, and ferric reducing antioxidant power (FRAP) assays (IC₅₀ = 46.7, 66.0, and 492.6, respectively). By column chromatography (CC) with elution of hexane and ethyl acetate at 8:2, 7:3, and 6:4 ratios, the isolation of this active extract yielded five fractions (C1–C5). Chemical structures of the constituents included in C1–C5 were elucidated by gas chromatography-mass spectrometry (GC-MS), electrospray ionization-mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR) and resolved as methyl gallate (C1, C2, C3, C4), gallic acid (C1, C2), fraxetin (C2, C3, C4, C5), and tomentin (C3). Mixture C2 (IC₅₀ DPPH and ABTS = 2.5 µg/mL) and C3 (IC₅₀ FRAP = 381 µg/mL) showed the highest antioxidant properties. Among the isolated fractions, C4 was the most potential agent in growth inhibition of six bacterial strains including Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes,Bacillus subtilis, and Proteus mirabilis (MIC = 5, 20, 30, 20, 25, and 20 mg/mL, respectively). All identified constituents exerted an inhibitory activity on the growth of Lactuca sativa, of which the mixture C3 performed the maximal inhibition on shoot (IC₅₀ = 49.4 µg/mL) and root (IC₅₀ = 47.1 µg/mL) growth. Findings of this study suggest that gallic acid, methyl gallate, fraxetin, and tomentin isolated from J. podagrica possessed antioxidant, antibacterial, and growth inhibitory potentials.

Functional Teas from the Stems of Penthorum chinense Pursh.: Phenolic Constituents, Antioxidant and Hepatoprotective Activity

Penthorum chinense Pursh (PCP), a medicinal and edible plant, is traditionally used for liver protection and treatment of liver diseases. In this study, we compared the differences of composition and activity of flowers, stems and leaves of PCP to select a bioactive part. The stems of PCP with stronger antioxidant activity (6.25-100 μg/mL) and lower cytotoxicity (25-200 μg/mL) than the flowers and leaves were a better bioactive part. Then the chemical composition and hepatoprotective effects of an aqueous extract and an 70% ethanolic extract made with stems of PCP were investigated. We found that the 70% ethanolic extract enriched more polyphenols and flavonoids and possessed significantly stronger hepatoprotective activity than the aqueous extract in the dose range of 25-200 μg/mL, which indicated that 70% ethanol is the better solvent of PCP in extraction technology. Moreover, ethyl acetate extract of stems of PCP (PSE) was used to evaluate the hepatoprotective ability of PCP against oxidative damage using an in vitro model of a normal rat's liver cell (BRL-3A). Besides, 12 phenolic compounds were identified from PSE by ultra-performance liquid chromatography followed by electrospray ionization mass spectrometry (UPLC-ESI-MS). Obtained results strongly support the traditional use of PCP and prove stems of PCP to be an important source of bioactive compounds associated with hepatoprotective activity.

Adsorption behaviour and mechanisms of cadmium and nickel on rice straw biochars in single- and binary-metal systems

Adsorption mechanisms and competition between Cd²⁺ and Ni²⁺ for adsorption by rice straw biochars prepared at 400 °C (RB400) and 700 °C (RB700) were investigated in this study. Based on the Langmuir model, the maximum adsorption capacities (mg g^-1) of Cd²⁺ and Ni²⁺ on RB400 and RB700 were in the order of Cd²⁺ (37.24 and 65.40) > Ni²⁺ (27.31 and 54.60) in the single-metal adsorption isotherms and Ni²⁺ (25.20 and 32.28) > Cd²⁺ (24.22 and 26.78) in the binary-metal adsorption isotherms. Cd²⁺ competed with Ni²⁺ for binding sites at initial metal concentrations >10 mg L^-1 for RB400 and > 20 mg L^-1 for RB700. The adsorption sites for Cd²⁺ and Ni²⁺ on the biochars largely overlapped, and the binding of Cd²⁺ and Ni²⁺ to these sites was affected by the occupation sequence of these metals. For Cd²⁺ and Ni²⁺ adsorption in the binary system, cation exchange and precipitation were the dominant adsorption mechanisms on RB400 and RB700, respectively, accounting for approximately 36% and 60% of the adsorption capacity. Competition decreased the contribution of cation exchange but increased that of precipitation and other potential mechanisms. Results from this study suggest that types and concentrations of metal ions should be taken into account when removing metal contaminants from water or soil using biochars.

Influence of pyrolysis temperature and feedstock on carbon fractions of biochar produced from pyrolysis of rice straw, pine wood, pig manure and sewage sludge

In this study, the influences of feedstock and pyrolysis temperature on carbon fractions of biochar were investigated. Four types of organic wastes (rice straw (RS), pine wood (PW), pig manure (PM) and sewage sludge (SS)) were pyrolyzed at different temperatures (300 °C, 400 °C, 500 °C, 600 °C and 700 °C). Biochar produced at low temperature exhibited high yields, high dissolved organic carbon (DOC) content and unstable organic carbon content. In contrast, biochar formed at high temperature showed high C content and C stability with a low O/C and H/C ratios. In addition, the biochar pyrolyzed from PW contained the lowest DOC of the four biochar types. The properties of DOC fractions (F1, F2 and F3) released from biochar differed depending on feedstock, pyrolysis temperatures, and extraction procedures. The highest specific ultraviolet absorbance at 254 nm of the F1 and F2 fractions were observed for RS biochar, suggesting that more aromatic organic matter was present in sequentially extracted fractions of RS biochar than in extracts from the other biochars. In addition, the hot water extracts (F2) mostly showed higher aromaticity than cold water extracts (F1). The stability of biochars was greatly enhanced at pyrolysis temperatures >500 °C. If the biochars produced in this study were to be used for carbon sequestration in soil, the first priority should be PW, followed in order by RS and PM.

Identification of genes revealed differential expression profiles and lignin accumulation during leaf and stem development in tea plant (Camellia sinensis (L.) O. Kuntze)

Lignin is a complex aromatic heteropolymer that plays essential roles in mechanical support, water transport, and response to biotic and abiotic stresses. The tea plant is a leaf-type beverage crop, which serves as a resource for non-alcoholic beverage tea. The content and distribution of lignin in tea plant leaves seriously affect the quality of tea. However, the biosynthetic pathways of lignin remain to be characterized in the tea plant. In the present study, lignin accumulation was investigated in tea plant leaves and stems at three developmental stages. The lignin content continuously increased during leaf and stem development in both tea plant cultivars 'Fudingdabai' and 'Suchazao.' The lignin distribution and anatomical characteristics of the tea plant leaves coincided with lignin accumulation and showed that lignin is mainly distributed in the epidermis, xylem, and vascular bundle sheath. 'Suchazao' exhibits a low lignin content and lacks a vascular bundle sheath. Twelve genes encoding the enzymes involved in the lignin biosynthesis of tea plant were identified and included CsPAL, CsC4H, Cs4CL, CsHCT, CsC3H, CsCCoAOMT, CsCCR, CsCAD, CsF5H, CsCOMT, CsPER, and CsLAC. The expression profiling of lignin biosynthesis-related genes and analysis of lignin accumulation may help elaborate the regulatory mechanisms of lignin biosynthesis in tea plant.

Molecular mechanism underlying orofacial antinociceptive activity of Vanillosmopsis arborea Baker (Asteraceae) essential oil complexed with β-cyclodextrin

BACKGROUND

Vanillosmopsis arborea Baker has recognized economic value owing to the high content of (-)-α-bisabolol (BISA) in the essential oil of its stem (EOVA). The antinociceptive effect of EVOA has already been demonstrated, and β-cyclodextrin (βCD) is known to improve the analgesic effect of various substances.

PURPOSE

Thus, we aimed to evaluate the orofacial antinociceptive effect of a complex containing EOVA-βCD in rodents.

METHODS

EOVA was obtained by simple hydrodistillation, and the essential oil was complexed with βCD. The animals (n = 6/group) were treated orally with EOVA-βCD (10 or 50 mg/kg), or vehicle (control), and subjected to cutaneous orofacial nociception (formalin, capsaicin, acidic saline or glutamate), corneal (hypertonic saline) or temporomandibular (formalin) tests. The expression of FOS protein was analyzed in the spinal cord. Molecular docking was performed using the 5-HT₃ and M₂ receptors and BISA.

RESULTS

The oral administration of EOVA-βCD reduced nociceptive behaviour. Moreover, EOVA-βCD decreased FOS expression. The molecular docking study indicates that BISA interacts with 5-HT3 and M2 receptors, indicating the potential mechanism of action of the tested compound.

CONCLUSIONS

Our results indicate that EOVA-βCD possesses orofacial antinociceptive effect, indicating that this complex can be used in analgesic drug development.

Enantiomeric β-carboline dimers from Picrasma quassioides and their anti-hepatoma potential

Four pairs of enantiomeric β-carboline alkaloids, (+/-)-kumudine A-D, along with their biosynthesis-related compound kumudine E, were obtained from the stems of Picrasma quassioides. Their structures, including the absolute configurations, were determined via extensive spectroscopic data combined with electronic circular dichroism (ECD) spectroscopic analyses and quantum mechanical ECD calculations. (+/-)-Kumudine A possessed a scaffold of β-carboline-phenylpropanoid adduct, which were the first examples of this type of β-carboline alkaloid from nature. The cytotoxicity assay against hepatocellular carcinoma Hep3B and HepG2 cells was evaluated by SRB assay, which showed that (-)-Kumudine B had stronger effect than its enantiomer (+)-Kumudine B in Hep3B cells. Moreover, further flow cytometry analysis also supported the enantioselectivity between (+)-Kumudine B and (-)-Kumudine B, suggesting that the compounds caused death of hepatoma cells through apoptosis induction.

Rice straw biochar modified by aluminum chloride enhances the dewatering of the sludge from municipal sewage treatment plant

Enhancement of the dewatering of the sludge by using rice straw biochar (RSB) modified by aluminum chloride (AlCl₃) was investigated, and the possible enhancing mechanisms were discussed. Results showed that the settled volume after 30 min (SV₃₀%), specific resistance to filtration (SRF), moisture content (MC) and capillary suction time (CST) of the sludge were decreased and the net sludge solids yield (Y_N) was increased by the increasing raw or modified RSB, which indicated a higher sludge dewaterability. When the dosage of the modified RSB was adjusted to 0.3 g(RSB)/g(dry sludge), SV₃₀%, SRF, MC and CST were decreased to 79.8%, 1.2 × 10¹² m/kg, 81.4% and 38 s, respectively, Y_N was increased to 19.4 kg/(m²·h). Furthermore, performance of the modified RSB in the dewatering of the sludge was significantly better than that of the raw RSB. For the enhancing mechanisms, charge neutralization occurred when the modified RSB (loaded with positively charged aluminum species on its surface) was dosed into the sludge system, thus destroying the stable sludge colloidal system, thus far easier to congregate the sludge particles, which enhanced the dewatering of the sludge. Another main enhancing mechanism was that after conditioned by the modified RSB, certain skeleton structures were formed in sludge cake to make water pass through easily by decreasing the extracellular polymeric substances (EPS) of the sludge. We found that the effectiveness of using the modified RSB to enhance the dewatering of the sludge is substantial and promising.

Indole alkaloid from Nauclea latifolia promotes LDL uptake in HepG2 cells by inhibiting PCSK9

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 (PCSK9) has been found to play a major role in atherosclerotic cardiovascular disease (ASCVD) by promoting hyperlipidemia. Its inhibition has therefore emerged as a viable drug target for improving the outcome of ASCVD. However, current monoclonal antibody PCSK9 inhibitors are considered cost ineffective and there is the need to discover new effective and cheaper small molecule alternatives.

PURPOSE

The methanolic and ethanolic crude extracts of Nauclea latifolia have been shown to possess anti-hyperlipidemic activity, but the chemical component(s) responsible for this activity and the mechanism of action have remained unknown. The objective of this study was therefore to identify N. latifolia constituents with anti-hyperlipidemic activity and to investigate the inhibition of PCSK9 as a probable mechanism of action.

METHOD

In the present study, compounds were isolated from the ethanolic extract of the stem of N. latifolia. The alkaloids were evaluated for their DiI-LDL uptake promoting activity in HepG2 cell. The most active compound was further assessed for its effect on low density lipoprotein receptor (LDLR) and PCSK9 protein expressions by western blot.

RESULTS

3R-3,14-dihydroangustoline (5), showed a relatively good activity in promoting LDL uptake (1.26-fold). It further increased LDLR protein expression and decreased the protein expression of PCSK9 in a dose dependent manner (1-50  µM).

CONCLUSION

Alkaloids from N. latifolia may serve as a source of new PCSK9 inhibitors.

Veluflavanones A-P, Cytotoxic Geranylated Flavanones from Dalbergia velutina Stems

Sixteen new geranylated flavanones, named veluflavanones A-P (1-16), and a known analogue (17), were isolated from Dalbergia velutina. The chemical structures of 1-17, as well as their absolute configurations, were determined by spectroscopic analysis and experimental ECD data. All isolated compounds were tested for their cytotoxicity against five human cancer cell lines. Compound 9 showed cytotoxicity toward KB, HeLa S3, and MCF-7 cells with IC₅₀ values of 9.9, 8.1, and 10.0 μM, respectively. In addition, compounds 10, 11, 14, and 16 exhibited selective cytotoxicity against HeLa S3 cells with IC₅₀ values of 6.6-9.9 μM.

Bioactive Diterpenoids from the Stems of Euphorbia royleana

Two ingenane- (1 and 2), two ent-atisane- (3 and 4), two ent-kaurane- (5 and 6), two ent-abietane- (7 and 8), and one ent-isopimarane-type (9) diterpenoid and 12 known analogues have been isolated from the methanolic extract of the stems of Euphorbia royleana. Their structures, including absolute configurations, were determined by extensive spectroscopic methods and ECD data analysis. The nitric oxide inhibitory activities of those diterpenoids were examined biologically in lipopolysaccharide-stimulated BV-2 cells, with compounds 1, 2, 5-7, 10, and 12 having IC₅₀ values lower than 40 μM. Molecular docking was used to investigated the possible mechanism of compounds 1, 2, 5-7, 10, and 12.

Antibacterial Activities of Crude Secondary Metabolite Extracts from Pantoea Species Obtained from the Stem of Solanum mauritianum and Their Effects on Two Cancer Cell Lines

Endophytes are microorganisms that are perceived as non-pathogenic symbionts found inside plants since they cause no symptoms of disease on the host plant. Soil conditions and geography among other factors contribute to the type(s) of endophytes isolated from plants. Our research interest is the antibacterial activity of secondary metabolite crude extracts from the medicinal plant Solanum mauritianum and its bacterial endophytes. Fresh, healthy stems of S. mauritianum were collected, washed, surface sterilized, macerated in PBS, inoculated in the nutrient agar plates, and incubated for 5 days at 30 °C. Amplification and sequencing of the 16S rRNA gene was applied to identify the isolated bacterial endophytes. These endophytes were then grown in nutrient broth for 7⁻14 days, after which sterilized Amberlite® XAD7HP 20⁻60 mesh (Merck KGaA, Darmstadt, Germany) resin was added to each culture to adsorb the secondary metabolites, which were later extracted using ethyl acetate. Concentrated crude extracts from each bacterial endophyte were tested for antibacterial activity against 11 pathogenic bacteria and two human cancer cell lines. In this study, a total of three bacterial endophytes of the Pantoea genus were identified from the stem of S. mauritianum. The antibacterial test showed that crude secondary metabolites of the endophytes and stem of S. mauritianum possessed antibacterial properties against pathogenic microbes such as Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa, with concentrations showing inhibition ranging from 0.0625 to 8.0000 mg/mL. The anticancer analysis showed an increase in cell proliferation when A549 lung carcinoma and UMG87 glioblastoma cell lines were treated with both the plant and endophytes' crude extracts. As far as we know, this is the first study of its kind on Solanum mauritianum in South Africa showing S. mauritianum endophytes having activity against some of the common human pathogenic organisms.

In vitro and in vivo toxicity assessment of biologically synthesized silver nanoparticles from Elaeodendron croceum

Background The cytotoxic properties of nanoparticles have attracted a great deal of attention in the field of nanoscience and nanotechnology due to their small size and ability to penetrate cellular membranes. Methods The silver nanoparticles were synthesized using Elaeodendron croceum stem bark and characterized. The oral acute toxicity studies were carried out by administration of 500, 1000, 2000 mg/kg body weight to Wister rats in respective groups. An in vitro cytotoxicity assay was evaluated in MDA-MB-231 breast cancer cells using the WST-1 Cell Proliferation assay. The percentage of cell viability after treatment with aqueous extracts of Elaeodendron croceum (ECE) and Elaeodendron croceum silver nanoparticles (ECAgNPs) was compared with that of paclitaxel. Results The in vivo studies revealed that the LD50 was higher than 2000 mg/kg and there was no significant difference (p>0.05) between the treatment groups compared with the control group for mean organ-to-body weight ratio except in the liver and in all hematological parameters except WBC and hematocrit. Similarly, there was no significant difference (p>0.05) for serum electrolytes (Na+, Mg2+ K+, Cl-, and Ca2+), total protein, urea, ɣ-glutamyl transferase (GGT), Aspartate aminotransferase (AST), Alkaline phosphatase (ALP), Alanine aminotransferase (ALT), albumin, total and conjugated bilirubin between the treatment and the control group. However, there were changes in creatinine, urea, and cholesterol. In the in vitro assays, ECE and ECAgNPs showed IC50 values of 70.87±2.99 and 138.8±3.98 µg/mL respectively against MDA-MB-231 cells compared to paclitaxel, which showed an IC50 value of 80 ng/mL. Conclusion The results showed that the LD50 of the ECE and ECAgNPs in Wister rats was determined to be greater than 2000 mg/kg body weight. The aqueous extract also showed more cytotoxic than the ECAgNPs suggesting that the toxic compounds in aqueous extract were involved in the capping of the AgNPs.

Effect of Drying Methods on the Microstructure, Bioactivity Substances, and Antityrosinase Activity of Asparagus Stems

The impacts of vacuum drying (VD), far-infrared drying (FIRD), hot air drying (HAD), and freeze drying (FD), as representative food drying methods, on structural characterization, bioactive substances, and antityrosinase activity of Asparagus have been assessed. The microstructure characterization by scanning electron microscopy indicated that VD treatment led to serious breaking of the vascular bundle and epithelial cells and provided higher free polyphenol (FP) and bound polyphenol (BP) contents. Besides, the smaller individual molecule (weight and hydroxy and phenolic rings) polyphenols bound to cellulose to a lesser extent than larger molecules, i.e., rutin and quercetin. In contrast, FD extracts possessed lower polyphenol contents but higher saponin and chlorophyll contents. The antityrosinase activity inhibition rates of FD and VD extracts were higher than those of FIRD and HAD for both mono- and diphenolase. The FP extract of VD, which possessed more polyphenolic compounds, had greater antityrosinase activity than BP.

MALDI- and LDI-MS saponin fingerprint of leaves and stick components of commercial yerba mate (Ilex paraguariensis)

Yerba mate (YM) is massively produced and consumed as an infusion in South America and spreading all over the world. This product is obtained from dried leaves of Ilex paraguariensis Saint Hilaire, mixed with fragments of dried branches (sticks). For its commercialization, YM must have a minimum percentage of leaves because its presence determines YM quality and price. Till today, a mechanical methodology to determine the relative amount of components (sticks, leaves, and powder) is used. There is not any modern analytical method that provides information for quick characterization of the YM components. Typical saponin fingerprints for leaves and sticks were found by using ultraviolet matrix-assisted laser desorption ionization and ultraviolet laser desorption ionization mass spectrometry. Then, their possible application as useful tools for quick characterization of components of commercial YM (leaves and sticks) is presented. Furthermore, fingerprints obtained from authentic samples of Ilex paraguariensis and Ilex dumosa are also included and discussed. Each Ilex show typical saponin fingerprints for leaves and sticks.

[Treatment of type 2 diabetes mellitus with the stem and leaf of blacktartary buckwheat and its effects on the pancreas and spleen]

OBJECTIVE

To investigate the therapeutic effects of the black buckwheat leaf (BBL) in type 2 diabetes mellitus mice and its effects on pancreas and spleen.

METHODS

Forty male C57 / B16 mice (SPF) were randomly divided into normal control (NC) group (n=10) and the experimental group (n=30), the experimental group were fed with high sugar and high fat, combined with intraperitoneal injection of streptozotocin in small dose to establish the model of type 2 diabetes mellitus (T2DM). Those thirty model mice were randomly divided into 3 groups (n=10), diabetes mellitus group (DM), low dose of BBL (DM+L) treated group, high dose of BBL (DM+H) treated group. The mice in the NC group and the DM group were given normal saline per day, and the DM+L group and DM+H group were treated with black tartary buckwheat at the doses of 0.21g/kg·d^-1 and 0.42g/kg·d^-1 respectively. After 14 days. All mice were executed by cervical dislocation, then blood samples were collected, pancreas and spleen were removed for subsequent experiments. The serum levels of fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TCH) and insulin were detected. TNF-α protein in spleen tissue was detected by ELISA kit. The morphology of pancreas tissue was observed by HE staining, and the spleen coefficient was calculated. The expression levels of insulin receptor substrate-1(IRS-1) mRNA and IRS-1 protein in pancreatic tissue were detected.

RESULTS

Compared with the control group, the serum levels of FBG, TC and TCH in the model group were increased significantly, while the serum level of insulin was decreased significantly (P＜0.05), the expression of TNF-α protein in spleen tissues was obviously raised, the expressions of IRS-1 mRNA and IRS-1 protein in pancreatic tissue in model group were decreased significantly (P＜0.05). Compared with the model group, the serum levels of FBG, TC and TCH were decreased significantly in the BBL treated groups. The serum insulin level, spleen coefficient, TNF-α protein expression level in spleen tissue, IRS-1 mRNA expression and IRS-1 protein expression levels in pancreatic tissue in BBL treated group were increased significantly (P＜ 0.05). High-dose black tartary buckwheat leaves (0.42g/kg·d^-1) exerted a more significant effect.

CONCLUSION

Stem and leaf of black bitter buckwheat has significant therapeutic effects on reducing blood sugar and blood fat in type 2 diabetic mice, and has certain protective effects on pancreas and spleen of diabetic mice.

Ergostane steroids from the ethanol extract of Dysoxylum mollissimum

Three new ergostane steroids, 7α-acetoxyl-ergosta-5,24(28)-diene-3β,4β,20S-triol (1), 7α-acetoxyl-ergosta-5,24(28)-diene-3β,4β-diol (2), and 7α-acetoxyl-ergosta-5,24(28)-3β-ol (3) were isolated from the ethanol extract of stem bark of Dysoxylum mollissimum BI. Structural elucidation of all the compounds was performed by spectral methods such as 1D and 2D (¹H-¹H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. All the isolated steroids were in vitro evaluated for their anti-inflammatory activity against COX-1 and COX-2. As a result, steroids 1-3 exhibited modest selective inhibition for COX-1 (>60%).

Improving ruminal digestibility of various wheat straw types by white-rot fungi

BACKGROUND

This study investigated the ruminal degradability of various wheat straw types by the white-rot fungi Ceriporiopsis subvermispora (CS) and Lentinula edodes (LE). Different cultivars (CV) of wheat straw at different maturity stages (MS) were treated with the fungi for 7 weeks and assessed for chemical composition and in vitro gas production (IVGP).

RESULTS

Both fungi showed a more pronounced degradation of lignin on a more mature straw (MS3; 89.0%) in comparison with the straw harvested at an earlier stage (MS1; 70.7%). Quantitative pyrolysis coupled to gas chromatography and mass spectrometry, using ¹³ C lignin as an internal standard ¹³ C-IS Py-GC/MS revealed that lignin in more mature straw was degraded and modified to a greater extent. In contrast, cellulose was less degraded in MS3, as compared to MS1 (8.3% versus 14.6%). There was no effect of different MS on the IVGP of the fungus-treated straws. Among the different straw cultivars, the extent of lignin degradation varied greatly (47% to 93.5%). This may explain the significant (P < 0.001) effect of cultivar on the IVGP of the fungal-treated straws. Regardless of the factors tested, both fungi were very capable of improving the IVGP of all straw types by 15.3% to 47.6%, (as compared to untreated straw), with CS performing better than LE - on different MS (33.6% versus 20.4%) and CVs (43.2% versus 29.1%).

CONCLUSION

The extent of lignin degradation caused by fungal treatment was more pronounced on the more mature and lignified straw, while variable results were obtained with different cultivars. Both fungi were capable of improving the IVGP of various straw types. © 2018 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

EB, Rocha CQ, Lima AS, Silva CR, Tangerina MMP, Lima Neto JS, Costa-Junior LM. Antiparasitic activities of hydroethanolic extracts of Ipomoea imperati (Vahl) Griseb. (Convolvulaceae)

Ipomoea imperati is widely used in tropical areas to treat several pathological conditions. The effect of this plant against parasitic species has not been investigated even being used for this purpose in the Brazilian northeastern. This study aimed to evaluate the anthelmintic and acaricide potential of a hydroethanolic extract of I. imperati leaves and stolons. I. imperati leaves and stolons were crushed and subjected to maceration in ethanol 70% (v/v), after which the solvent was removed using a rotary evaporator. The chromatographic profile of the extract was obtained by UV Spectrum high-performance liquid chromatography and compounds were identified by liquid chromatography/electrospray ionization tandem mass spectrometry. Identification of the compounds present in the extract was achieved by comparing their retention times and UV spectra with data in the literature. Anthelmintic activity was evaluated by larval exsheathment inhibition assays using Haemonchus contortus larvae and five concentrations of each extract ranging from 0.07 to 1.2 mg/mL. Acaricide activity was evaluated via larval immersion of Rhipicephalus microplus in eight concentrations of each extract ranging from 5.0 to 25.0 mg/mL. Live and dead larvae were counted after 24 hours. The median inhibitory concentration (IC₅₀) for H. contortus larvae and the median lethal concentration (LC₅₀) for R. microplus larvae were calculated. Twelve compounds were observed in the hydroethanolic extract of leaves, with a predominance of the aglycone form of flavonoids and tannins. This extract was effective against H. contortus larvae, presenting an average inhibitory concentration of 0.22 mg/mL, but showed no activity toward R. microplus larvae. The stolon hydroethanolic extract presented 11 compounds, with phenolic acids and glycosylated flavonoids prevailing. This extract showed low activity on R. microplus and no effect on inhibiting H. contortus larval exsheathment at the concentrations tested. This study is the first to assess the anthelmintic and acaricidal activities of I. imperati. Data reported confirm promising potential of I. imperati leaves hydroethanolic extract against H. contortus. This effect could be due to its secondary compounds presents in this extract, such as procyanidin, kaempferol, isoquercitrin and rutin.

Lignin-polysaccharide interactions in plant secondary cell walls revealed by solid-state NMR

Lignin is a complex aromatic biopolymer that strengthens and waterproofs plant secondary cell walls, enabling mechanical stability in trees and long-distance water transport in xylem. Lignin removal is a key step in paper production and biomass conversion to biofuels, motivating efforts to re-engineer lignin biosynthesis. However, the physical nature of lignin's interactions with wall polysaccharides is not well understood. Here we show that lignin self-aggregates to form highly hydrophobic and dynamically unique nanodomains, with extensive surface contacts to xylan. Solid-state NMR spectroscopy of intact maize stems, supported by dynamic nuclear polarization, reveals that lignin has abundant electrostatic interactions with the polar motifs of xylan. Lignin preferentially binds xylans with 3-fold or distorted 2-fold helical screw conformations, indicative of xylans not closely associated with cellulose. These findings advance our knowledge of the molecular-level organization of lignocellulosic biomass, providing the structural foundation for optimization of post-harvest processing for biofuels and biomaterials.

A comparative study of biogasification of wheat straw, sugarcane bagasse and pressmud

A study to compare biogas production potentials of wheat straw, sugarcane bagasse and pressmud was conducted at pH 8.0, temperature 40 °C and substrate concentration 20 g/L. Raw substrates were thermogravimetrically and Fourier-transform infrared spectroscopically characterised. TGA showed the weight loss of samples attributable to moisture, hemicellulose, cellulose and lignin losses. FTIR analysis indicated functional groups characteristics of hemicellulose, cellulose and lignin. Biogas production was the maximum between 10th and 25th day for all the tests. WS with 10% inoculum showed the highest cumulative biogas production of 370 mL/g followed by the SB (316 mL/g) and PM (211 mL/g) counterparts. The corresponding values with 5% inoculum were 303 mL/g (WS), 244 mL/g (SB) and 152 mL/g (PM). The inoculum volume also positively affected the cumulative biogas production (22.1, 29.5 and 38.8% respectively). The higher volatile fatty acids as observed in case of WS which further facilitated higher biogas production could be due to its maximum volatile solids content (88.9%) and water swelling capacity (7.37). A consistently increasing trend in the methane content (varying between 54 and 61%) in all the tests was observed till the 20th day. The biogas (7.7-21.7 mL/g) and the methane (35-42%) contents showed a decreasing trend thereafter, the lowest being observed during the 35-40-day period.

CuO and CeO2-doped catalytic material synthesized from red mud and rice husk ash for p-xylene deep oxidation

CuO-CeO₂ catalysts supported on material synthesized from red mud and rice husk ash (CuO-CeO₂/ZRM) were prepared by co-impregnation method. The role of CeO₂ additive in the improvement of physicochemical properties and catalytic activity of CuO-CeO₂/ZRM catalysts were emphasized. Several techniques, including Brunauer-Emmett-Teller Nitrogen physisorption measurements, X-ray powder diffraction, hydrogen temperature programed reduction, scanning electron microscopy and transmission electron microscopy (TEM) were used to investigate the properties of catalysts. Crystallite size calculated by Scherrer' equation was 17.4 - 21.8 nm. Modification of 5 wt% CuO/ZRM catalyst with CeO₂ had reduced the size of the nanoparticles leading to a significant enhancement of the catalytic activity in p-xylene deep oxidation at temperature range of 275 - 400 °C. The 5 wt% CuO/ZRM sample promoted by 3 wt% of nanoparticle CeO₂ with the average size of 17.5 nm and BET surface area of 31.3 m² g^-1 exhibited the best activity for p-xylene deep oxidation. In this sample, the conversion of p-xylene reaches to 90% at 350 °C.

Syringa pinnatifolia Hemsl. fraction protects against myocardial ischemic injury by targeting the p53-mediated apoptosis pathway

BACKGROUND

Peeled stems of Syringa pinnatifolia Hemsl. (SP) have been widely used to treat extra "He-Yi" induced myocardial ischemia for hundreds of years in Inner Mongolia, China and previous result showed that intragastric pretreatment with total extract (T) of SP has a protective effect against myocardial infarction (MI).

HYPOTHESIS

This study aims to describe the pharmacological investigation and chemical characterization of the major (M) and minor (N) fractions obtained from T through column chromatography fractionation on macroporous resin and to explore whether the regulatory effects were linked to the p53-mediated apoptosis pathways.

STUDY DESIGN

Left anterior descending (LAD) coronary artery-ligated mice and H9c2 cells cultured in serum-free medium under hypoxic conditions were treated with T, M, and N.

METHODS

Echocardiography was performed and biomarkers in serum were determined in mice, and pathological changes were observed through histopathology assay. Immunofluorescence staining and qRT-PCR were used to detect the expression levels of p53 in heart tissue. Flow cytometry was used to measure the level of apoptosis and caspase-3 activity in H9c2 cells. Western blot analysis was conducted to detect p53 and p53-mediated proteins apoptosis pathways of in both tissue and H9c2 cells.

RESULTS

Both T and M have an equivalent cardioprotective effect whereas N is non-active. M decreased MI-induced myocardial compensatory expansion by decrease of left ventricular end-systolic diameter (LVESd) and left ventricular end-diastolic diameter (LVEDd) and prevented decreases in ejection fraction (EF) and fractional shortening (FS). The MI-induced increased levels of creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and hypersensitive C-reactive protein (hs-CRP) were decreased and the expanded infarction size was reduced. M could also improve cell viability and inhibit apoptosis in H9c2 cells under hypoxic conditions. Immunofluorescence and qRT-PCR assay showed that M suppressed p53 expression in the myocardium. Western blot analysis showed that M could prevent MI-induced activation of p53-mediated apoptosis pathway in both myocardium and H9c2 cells.

CONCLUSION

The results demonstrated that M may protect against myocardial ischemia by improving cardiac function and inhibiting cardiomyocytes apoptosis. Overall, the present findings supported the clinical application of SP and enriched the research of anti-myocardial ischemia drug from traditional medicines.

New Cytotoxic Cycloartane Triterpenes from the Aerial Parts of Actaea heracleifolia (syn. Cimicifuga heracleifolia)

One new 15,16-seco-cycloartane triterpene (1: ), three new cycloartane triterpene glycosides (2: -4: ), and five known compounds (5: -9: ) were isolated from the aerial parts of Actaea heracleifolia. The chemical structures of these compounds were determined on the basis of NMR analysis, HRTOF-ESIMS data, and other spectroscopic methods. Selected compounds were evaluated for their cytotoxicity against human tumor cell lines (HL-60, SMMC-7721, A549, MCF-7, and SW480) in vitro. Compounds 3: and 4: showed weak activity against the HL-60, A-549, and MCF-7 cell lines with IC₅₀ values ranging from 21.34 to 36.98 µM.

Screening and determination for potential acetylcholinesterase inhibitory constituents from ginseng stem-leaf saponins using ultrafiltration (UF)-LC-ESI-MS2

INTRODUCTION

Previous studies have demonstrated that several ginsenosides have remarkable inhibitory effect on acetylcholinesterase (AChE). In the present study, ginseng stem-leaf saponins (GSLS) can improve learning and memory of Alzheimer's disease patients. However, much comprehensive information regarding AChE inhibition of GSLS and its metabolites is yet unknown.

OBJECTIVE

The present study aims to screen and determine the potential of AChE inhibitors (AChEIs) from GSLS.

METHODOLOGY

The active fraction of the GSLS detected in vitro AChE inhibition assays was selected as a starting material for the screening of the potential of AChEIs using ultrafiltration liquid chromatography coupled to electrospray ionisation tandem mass spectrometry (UF-LC-ESI-MS² ).

RESULTS

The results showed that 31 ginsenosides were identified with analysis using rapid resolution liquid chromatography with a diode array detector combined with electrospray ionisation tandem mass spectrometry (RRLC-DAD-ESI-MS² ) from the active fraction, and there are 27 compounds with AChE binding activity. Among them, 11 ginsenosides were evaluated and confirmed using in vitro enzymatic assay, and ginsenosides F₁ , Rd, Rk₃ , 20(S)-Rg₃ , F₂ and Rb₂ were found to possess strong AChE inhibitory activities.

CONCLUSION

The proposed UF-LC-ESI-MS² method was a powerful tool for the discovery of AChEIs from traditional Chinese medicine (TCM).

Total content of kaurene diterpenes in Annona vepretorum stems via 1 H qNMR: A method for speeding the identification of bioactive extracts

INTRODUCTION

Kaurene diterpenes (KDs) constitute a chemical class often found in the genus Annona with interesting biological activities. To date, chromatographic tools have been mostly used to determine KDs. Quantitative nuclear magnetic resonance (qNMR) has distinguished itself in quantitative estimation of natural products and is an interesting choice to assess total KD contents.

OBJECTIVE

To establish a ¹ H qNMR method for determining the total KD contents in extracts and fractions obtained from Annona vepretorum stems.

METHODOLOGY

Stems were extracted with hexane and methanol, resulting in the hexane extract (HEX-E) and the methanol extract (MeOH-E). The former was partitioned with the acid-base method to obtain the total alkaloid fraction (TA-F) and the neutral dichloromethane fraction (NDM-F). ¹ H qNMR measurements were performed on 400 MHz with samples solubilized in deuterated dimethyl sulfoxide. Quantification was carried out using the signals at 4.71 and 4.78 ppm related to hydrogens of the exocyclic double bond of the basic skeleton of KDs and gallic acid as the standard reference. The selectivity, intra- and inter-day precision, reproducibility, limit of detection, limit of quantification, and robustness of the methodology were evaluated.

RESULTS

Using the newly developed method, the total KD contents (in μg/mg) were 653.80 ± 12.15 (HEX-E), 458.90 ± 25.94 (NDM-F), 375.60 ± 27.52 (TA-F), and 315.10 ± 19.20 (MeOH-E). For determining the most promising bioactive sample, the KD contents and the sample discriminations obtained by principal component analysis were correlated to the antibacterial activity. Such approach pointed out HEX-E as a potential source of KDs.

CONCLUSION

The developed method offers a fast and simple way of determining total KD contents.

Quantification of Phenolic Compounds from Fadogia agrestis and Dietary Supplements using UHPLC-PDA-MS

Fadogia agrestis is used in traditional African medicine as an analgesic and for anti-inflammatory and aphrodisiac activities. An ultra-high-performance liquid chromatography method was developed for the determination of 11 chemical constituents from roots and aerial parts of F. agrestis. The separation was achieved within 7 min by using C-18 column material and a water/acetonitrile mobile phase, both containing 0.1% formic acid gradient system with a temperature of 45 °C. The method was validated for linearity, repeatability, limits of detection, and limits of quantification. The limits of detection of phenolic compounds were found to be in the range from 0.025 to 0.1 µg/mL. The wavelengths used for quantification with the photodiode array detector were 238, 254, 291, and 325 nm. Twelve of 17 dietary supplements contained phenolic compounds in the range from 0.3 to 2.7 mg/d. The phenolic compounds were not detected in five dietary supplements. Liquid chromatography-mass spectrometry coupled with electrospray ionization interface method is described for the identification and confirmation of compounds from plant samples and dietary supplements claiming to contain F. agrestis. This method involved the use of [M + H]⁺ and [M + Na]⁺ ions in the positive mode and [M - H]^- ions in the negative mode with extractive ion monitoring. The developed method is simple, economic, rapid, and especially suitable for quality control and chemical fingerprint analysis of F. agrestis.

Comprehensive characterisation of polyphenols in leaves and stems of three anti-dengue virus type-2 active Brazilian Faramea species (Rubiaceae) by HPLC-DAD-ESI-MS/MS

INTRODUCTION

The methanol (MeOH) leaf extracts of the species Faramea bahiensis, F. hyacinthina and F. truncata (Rubiaceae) have previously shown in vitro non-cytotoxic and anti-dengue virus serotype 2 (DENV2) activities in human hepatocarcinoma cell lineage (HepG2). Chemical studies have led to the isolation of major flavonoids, but quite complex fractions of phenolic compounds still remain.

OBJECTIVE

To complete the study of phenolic compounds in the leaves and to access the presence of these compounds in the stems of these Faramea spp. by online high-performance liquid chromatography-diode array detector-electrospray ionisation tandem mass spectrometry (HPLC-DAD-ESI-MS/MS), as well as to evaluate the in vitro cytotoxic and anti-DENV2 activities of their MeOH stem extracts.

METHODOLOGY

The identification was performed by comparing retention times, UV and mass spectra with those of available standards and by using the mechanisms and fragmentation patterns established in previous studies. The effects of the extracts in DENV2 infected HepG2 cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The virus titer was quantified by plaque assay.

RESULTS

The study led to the characterisation of 31 phenolic compounds including flavonoid O- and C-glycosides, phenolic acids and one coumarin. The stem extracts from F. hyacinthina and F. bahiensis presented a similar bioactivity to those of their leaves but a loss of cytoprotective activity of F. bahiensis and a higher cytotoxicity of F. truncata were observed.

CONCLUSIONS

This research allowed a detailed phenolic composition of three bioactive Faramea species to be achieved, thus contributing to the study of this genus and providing valuable information for further phytotherapeutic applications.

Anaerobic co-digestion of poultry litter and wheat straw affected by solids composition, free ammonia and carbon/nitrogen ratio

In this study, the effects of three total solids levels (2%, 5% and 10% TS) of the mixtures of poultry litter and wheat straw at different percent volatile solids from wheat straw (0%, 25% and 50% VSWS), free ammonia nitrogen (FAN) and C/N ratio on co-digesting poultry litter with wheat straw were studied in batch experiments operated at 37 °C. The results showed that adjusting the substrate C/N ratio alone could not always result in high methane yields and biogas volumes. The maximum CH₄ yield of 201 mL g^-1 initial VS was observed in the 5% TS category with VSWS being 50%. The highest specific biogas volume produced (318 mL g^-1 initial VS) was also obtained in the same solid category. A polynomial regression between FAN and the methanogenic activity was obtained with the correlation coefficient being 0.9472. A FAN inhibitory threshold concentration of 253.9 mg L^-1 was found, and a total loss of methane production occurred when the FAN concentration reached 1000 mg L^-1. An optimal TS content for anaerobic digestion of poultry litter with wheat straw was around 4.15% to achieve the best biogas yield. Similarly, for digesting poultry litter without addition of wheat straw, the TS content should be kept at around 6.8%.

Heavy Metal Accumulation in Common Aquatic Plants in Rivers and Lakes in the Taihu Basin

We investigated the concentrations of 10 heavy metals in Potamogeton malaianus, Nymphoides peltata, Eichhornia crassipes, and Hydrilla verticillata to evaluate their potential to bioaccumulate heavy metals and related influencing factors in Taihu Lake. Enrichment factor (EF) values of Cu, Cr, Mn, Ni, Zn, Co, Pb, and V were above 2.0, indicating moderate to significant contamination in sediment. Most of Ti, V, Cr, Mn, and Ni in P. malaianus, E. crassipes, and H. verticillata and V in N. peltata were within excess/toxic level in plants, but higher than normal level. Even though no aquatic plants in this study were identified as a hyperaccumulator, relatively higher concentrations in aquatic plants were found in Taihu Lake than have been found in other previous studies. Heavy metal in submerged plants, especially in their stems, seemed to be more closely related to metals in water and sediment than those in floating-leaf plants. Ratios of metals in stem versus leaves in all plants ranged from 0.2 to 25.8, indicating various accumulation capabilities of plant organs. These findings contribute to the application of submerged aquatic plants to heavy metal removal from moderately contaminated lakes.

Polyphenol enriched ethanolic extract of Cajanus scarabaeoides (L.) Thouars exerts potential antifilarial activity by inducing oxidative stress and programmed cell death

Development of antifilarial drug from the natural sources is considered as one of the most efficacious, safe, and affordable approaches. In this study, we report the antifilarial activity of a leguminous plant Cajanus scarabaeoides (L.) Thouars. The polyphenol-rich ethanolic extract obtained from the stem part of the plant C. scarabaeoides (EECs) was found to be efficient in killing the filarial nematode Setaria cervi in all the three developmental stages viz. oocytes, microfilariae (Mf) and adults with LD₅₀ values of 2.5, 10 and 35 μg/ml, respectively. While studying the molecular mechanism of action, we found that induction of oxidative stress plays the key role in inducing the mortality in S. cervi. The redox imbalance finally results in activation of the nematode CED pathway that executes the death of the parasite. Intriguingly, EECs was found to be selectively active against the worm and absolutely non-toxic to the mammalian cells and tissues. Taken together, our experimental data demonstrate that C. scarabaeoides can be chosen as an affordable natural therapeutic for treating filarial infection in the future with high efficacy and less toxicity.

Effect of Wheat Cultivar on the Concentration of Fusarium Mycotoxins in Wheat Stems

Effective control of Fusarium-mycotoxin accumulation in grain affected by Fusarium head blight (FHB) (caused by Fusarium graminearum) begins with selecting moderately resistant wheat cultivars; however, little is known about how this resistance affects mycotoxin levels in the stem. A study was conducted from 2011 to 2014 in a mist-irrigated FHB nursery in Urbana, IL to determine whether the FHB resistance class of a cultivar (very susceptible, susceptible, moderately susceptible, and moderately resistant) affects the concentration of Fusarium mycotoxins in the stem. FHB incidence, FHB severity, and Fusarium-damaged kernel ratings were collected and used to calculate FHB index; incidence, severity, and kernel damage (ISK) index; and deoxynivalenol (DON), incidence, severity, and kernel damage (DISK) index. Grain was assayed for levels of DON, and the bottom 25 cm of plant stems was collected from each plot and assayed for DON, 3-acetyl-deoxynivalenol (3ADON), and 15-acetyl-deoxynivalenol (15ADON). Significant differences in DON concentration in the grain were detected among cultivars (P = 0.0001) and for the concentration of all DON (P = 0.003), 3ADON (P = 0.03), and 15ADON (P < 0.0001) in the stem. Significant differences among resistance classes were observed for FHB index value (P < 0.0001), ISK index (P = 0.006), and DISK index (P = 0.004). In all years of this study, the concentration of DON in the grain and the concentrations of all mycotoxins in the stem were consistently lower in the moderately resistant cultivars. All three indices were poor indicators of mycotoxin concentrations in the stem. Overall, the selection of a moderately resistant cultivar provides effective control of DON accumulation in the grain and mycotoxin accumulation in the stem.

Biochar amendment immobilizes arsenic in farmland and reduces its bioavailability

This study aimed to determine effects of biochar derived from wheat straw at 500 °C on arsenic immobilization in a soil-Brassica campestris L system. When the soils amended with 4% modified biochar (MBC), 0.5% Fe grit as zero-valent iron (ZVI), 0.5% Fe grit + 4% MBC (ZMBC), 0.5% ZVI + 4% biochar (ZBC), 4% biochar (BC), and control (without amendments), it confirmed that available arsenic concentration in soils occurred in the following order: ZMBC < MBC < ZVI < ZBC < Control < BC. Water-soluble As (WSAs) was reduced by 89.74% and 92.30% in MBC- and ZMBC-amended soils, respectively, compared to the control. When MBC applied into soil, As uptake of shoot and root decreased by 44.55% and 45.40%, respectively, and ZMBC resulted in 74.92% and 71.80% reduction in shoot and root As of Brassica campestris L. Immobilization effect of As in ZBC was also observed though BC elevated plant As uptake significantly. The immobilization effect of MBC was mainly attributed to Fe₂O₃ impregnation illustrated by x-ray diffraction (XRD) and scanning electron microscopy (SEM) images through sorption, precipitation, and coprecipitation. Such Fe containing complexes might impede As translocation from root to shoot and subsequently reduce As accumulation in the plant with modified biochar amendment.

Modified grape stem as a renewable adsorbent for cadmium removal

In order to aggregate value to the grape stem (wastes), this research aim was to increase the adsorption capacity of Cd²⁺ by chemical modifications on grape stems. The grape stems were milled and sieved, resulting in the biosorbent, which was used for the chemical modifications resulting in E. H₂O₂, E. H₂SO₄ and E. NaOH. These were characterized by such means as its pH_PZC, Fourier transform-infrared (FTIR) spectroscopy, porosimetry, thermal stability and scanning electron microscopy. The ideal adsorption dose, the pH influence on adsorption, kinetics, equilibrium and thermodynamics studies were carried out. The FTIR spectroscopy suggests the occurrence of carboxyl, amine, and phenolic acting in Cd²⁺ sorption. The modification on grape biomass caused small increase in pore volume and specific surface area. The grape-based adsorbents have similar thermal stability, with irregular appearance and heterogeneity. 5.0 g kg^-1 is the best adsorption dose. The modified adsorbents exhibited increase in Cd²⁺ removal of 66% for E. NaOH, 33% for E. H₂O₂ and 8.3% for E. H₂SO₄. The use of grape stem as adsorbent is an attractive alternative, because its wastes have great availability, low cost and great potential for metal adsorption processes.

Alkaloids from the stems and rhizomes of Sinomenium acutum from the Qinling Mountains, China

Thirteen undescribed alkaloids (sinotumines A-M), including five oxoisoaporphine, a benzo[h]quinoline, an aporphine, two protoberberine, two hasubanane, and two proaporphine alkaloids, and 50 known analogues were isolated from the 95% aqueous EtOH extract of the stems and rhizomes of Sinomenium acutum. The structures and absolute configurations of the isolates were elucidated on the basis of comprehensive analysis of 1D and 2D NMR, HRMS, single-crystal X-ray diffraction, and comparison of the experimental and calculated electronic circular dichroism (ECD) data. Sinotumine F, a rare benzo[h]quinoline alkaloid, was speculated as an oxidation product of the oxoisoaporphine alkaloid, and its putative biosynthetic pathway is proposed. Sinotumines L and M are the first samples of proaporphine-based heterodimers coupled with 1-heptanone and coniferol alcohol moiety, respectively. The T-cell suppression and NO inhibition effects of the isolates were evaluated.

Mechanical and moisture barrier properties of corn distarch phosphate film influenced by modified microcry stalline corn straw cellulose

BACKGROUND

In this paper, a novel modified microcrystalline corn straw cellulose (MMCSC) was prepared by ultrasonic/microwave-assisted treatment. Effective incorporation of MMCSC into corn distarch phosphate (CDP)-based composite films was investigated.

RESULTS

As the proportion of MMCSC was increased, tensile strength increased initially before decreasing, and the elongation at break always decreased. The composite film of MMCSC20 showed the lowest water vapor permeability (2.917 × 10^-7 g m^-1 h^-1 Pa^-1 ). The measurement of surface color showed that by the increasing of the MMCSC proportion in composite films, the L^* and b^* values and the total color difference (ΔE^* ) increased, while a^* values decreased. Fourier transform infrared spectroscopy and X-ray diffraction analysis indicated that, with the incorporation of MMCSC, the stable structure of the films was enhanced through cross-linking and the crystallinity was increased. A scanning electron microscopy study revealed the surface microstructure of films (MMCSC0-MMCSC30) was smooth and homogeneous, and there was no distinct separation in the matrix of composite films.

CONCLUSION

The incorporation of suitable MMCSC could improve the properties of composite films. The CDP-MMCSC films, which are completely biodegradable and environmental friendly, have a high potential to be used for food packaging. © 2018 Society of Chemical Industry.