Extracellular enzymes catalyze rate‐limiting steps in soil organic matter decomposition, and their activities (EEAs) play a key role in determining soil respiration (SR). Both EEAs and SR are highly ...sensitive to temperature, but their responses to climate warming remain poorly understood. Here, we present a meta‐analysis on the response of soil cellulase and ligninase activities and SR to warming, synthesizing data from 56 studies. We found that warming significantly enhanced ligninase activity by 21.4% but had no effect on cellulase activity. Increases in ligninase activity were positively correlated with changes in SR, while no such relationship was found for cellulase. The warming response of ligninase activity was more closely related to the responses of SR than a wide range of environmental and experimental methodological factors. Furthermore, warming effects on ligninase activity increased with experiment duration. These results suggest that soil microorganisms sustain long‐term increases in SR with warming by gradually increasing the degradation of the recalcitrant carbon pool.
The links between extracellular enzyme activities (EEAs) and soil respiration (SR) under warming scenarios remain poorly understood, despite both EEAs and SR are highly sensitive to temperatures. By synthesizing data from 56 studies, we showed that warming significantly increased ligninase activity by 21.4% and SR by 15.8%, while warming had no effect on cellulase activity. Moreover, increases in ligninase activity were positively correlated with SR and warming duration. These results reveal a novel mechanism that warming‐induced shifts in carbon‐degrading EEAs could contribute to the self‐reinforcing SR to long‐term climate warming.
Soils always receive microplastics (MPs) from plastic mulching, compost, and sewage irrigation, but the effects of MPs on soil environment remain largely unexplored. The objectives of this study were ...to investigate the effects of three MPs (membranous polyethylene (PE), fibrous polypropylene (PP), and microsphere PP) on enzyme activities and microbial community structure in one loamy and sandy soil. The concentration of microsphere PP (2 mg/g) was one‐tenth of those of the other two MPs (20 mg/g). The results showed that the effects of three MPs on urease, dehydrogenase, and alkaline phosphatase activities followed the order: fibrous PP > membranous PE > microsphere PP, membranous PE > microsphere PP > fibrous PP and fibrous PP > microsphere PP > membranous PE, respectively. Results from high‐throughput sequencing of 16S rRNA revealed that the membranous PE and fibrous PP raised the alpha diversities of the soil microbiota, whereas the diversity indexes of microbiota on MPs surfaces were significantly lower than those in the amended soils. MPs significantly altered the microbial community structure, especially for the enrichment of Acidobacteria and Bacteroidetes, the depletion of Deinococcus‐Thermus and Chloroflexi. Aeromicrobium, Streptomyces, Mycobacterium, Janibacter, Nocardia, Arthrobacter were prone to inhabit on the MPs surfaces.
Practitioner points
Three microplastics had different effects on soil enzyme activities.
Fibrous PP had a more persistent effect on microbial activity.
Membranous PE and fibrous PP raised the alpha diversities of soil microbiota.
The effects of membranous PE and fibrous PP on microbial communities were similar.
Distinct microbial communities were enriched on the surfaces of microplastics.
The effects of different MPs on soil microbial community.
The Book covers this whole field, from the discovery of structurally new and bioactive natural products (including biomacromolecules), from marine macro-/micro-organisms, to the pharmacodynamics, ...pharmacokinetics, metabolisms, and mechanisms of marine-derived lead compounds, both in vitro and in vivo, along with the synthesis and/or structural optimization of marine-derived lead compounds and their structure–activity relationships. Taken together, this Special Issue reprint not only provides inspiration for the discovery of marine-derived novel bioactive compounds, but also sheds light on the further research and development of marine candidate drugs.
Majority of the representative drugs customarily interact with multiple targets manifesting unintended side effects. In addition, drug resistance and over expression of the cellular efflux‐pumps ...render certain classes of drugs ineffective. With only a few innovative formulations in development, it is necessary to identify pharmacophores and novel strategies for creating new drugs. The conjugation of dissimilar pharmacophoric moieties to design hybrid molecules with an attractive therapeutic profile is an emerging paradigm in the contemporary drug development regime. The recent decade witnessed the remarkable biological potential of 1,3,5‐triazine framework in the development of various chemotherapeutics. The appending of the 1,3,5‐triazine nucleus to biologically relevant moieties has delivered exciting results. The present review focuses on 1,3,5‐triazine based hybrid molecules in the development of pharmaceuticals.
The scavenging behavior of a series of phenolic and anilines compounds toward H2O2 and DPPH was examined. The efficient concentration (EC50) was calculated for all compounds under investigation by ...using H2O2-scavenging activity assay. The antiradical efficiency (AE) and EC50 were calculated for all investigated compounds by applying DPPH scavenging activity assay. Wide differences among compounds in each series and between the two series were observed. In H2O2-scavenging activity assay, the anilines series were more active than the phenolic series due to the reduction properties of the anilines compounds. While in the DPPH scavenging activity, the phenolic compounds were more active than the anilines compounds due to the lower bond dissociation energies (BDE) of O–H than that of N–H. So, the phenolic compounds were comparatively easier to lose H atom than anilines. The antioxidant activity related to the compound structure was found to be dependable on the number of the included active group (OH or NH2). The more active compound is the more included active groups. The position of the active groups also plays an important role of structure–antioxidant relationship activity. The ortho position was found to be the more active one, due to its ability to form intramolecular hydrogen bonding (iHB), followed by para position and then meta position of compounds.
The synthesis and biological activity evaluation of benzenesulfonyl hydrazones is quite frequently encountered in scientific literature. This class of compounds is very interesting due to the wide ...spectrum of potential applications in the field of medicinal chemistry. The benzenesulfonyl hydrazones possess mainly antibacterial, antifungal, anticancer, antidepressant properties, activity against Alzheimer's disease, insecticidal activity and ability to inhibit the activity of enzymes. This review is an attempt to gather the literature findings on the most promising bioactive benzenesulfonyl hydrazones.
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•Examples of bioactive benzenesulfonyl hydrazones are gathered in this review•Potential application of benzenesulfonyl hydrazones in the field of medicinal chemistry is presented.•The benzenesulfonyl hydrazones possess mainly antibacterial, antifungal, anticancer, antidepressant properties, activity against Alzheimer's disease, insecticidal activity and ability to inhibit the activity of enzymes.
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•Schiff base ligands and their metal complexes.•Pharmacological application of Schiff base metal complexes.•Anti-bacterial activity.•Anti-fungal activity.•Anti-oxidant ...activity.•Anti-cancer activity.•Anti-diabetic activity.
Multidrug-resistant infections have placed a financial and health burden on the health-care system and population. As a result, human health was faced major issues due to multidrug resistance. In the past few years various organic compounds normally used not for a long time which have a pure organic mechanism of action and instead require more bio-activation or further stimulation.Numerous studies demonstrated that bioactive compounds require trace amounts of metal ions incorporated into their chemistry for improvement of their potential to fight resistance aggressively.Deficiency of metal ions may also cause many diseases such as retardation in growth, severe anemia and cardio-vascular disease in children. These problems are overcomes by introducing new approaches with remarkable pharmacological applications and new action of mechanism that improved the efficiency of the drugs. This review explains the pharmacological importance of Schiff base metal complexes with known chemical structures reported in last five years. Bioinorganic molecules have played an important role for the synthesis of new “Metal Based Drugs”. In recent years, there has been a surge in attention to used Schiff base metal complexes to cure a variety of disorders which are challenging to treat with traditional methods. Metal complexes provided innovative opportunities due to its particular properties and acting as an intermediate between conventional inorganic and organic compounds. In recent years, the great deals of interest in the applications of Schiff base metal complexes for the treatment of several diseases that are challenging to treat with previously used conventional methods.
Students played a critical role in the Sandinista struggle in Nicaragua, helping to topple the US-backed Somoza dictatorship in 1979—one of only two successful social revolutions in Cold War Latin ...America. Debunking misconceptions, Students of Revolution provides new evidence that groups of college and secondary-level students were instrumental in fostering a culture of insurrection—one in which societal groups, from elite housewives to rural laborers, came to see armed revolution as not only legitimate but necessary. Drawing on student archives, state and university records, and oral histories, Claudia Rueda reveals the tactics by which young activists deployed their age, class, and gender to craft a heroic identity that justified their political participation and to help build cross-class movements that eventually paralyzed the country. Despite living under a dictatorship that sharply curtailed expression, these students gained status as future national leaders, helping to sanctify their right to protest and generating widespread outrage while they endured the regime’s repression. Students of Revolution thus highlights the aggressive young dissenters who became the vanguard of the opposition.
We have recently developed a simple algorithm for the classification of household and locomotive activities using the ratio of unfiltered to filtered synthetic acceleration (gravity-removal physical ...activity classification algorithm, GRPACA) measured by a triaxial accelerometer. The purpose of the present study was to develop a new model for the immediate estimation of daily physical activity intensities using a triaxial accelerometer. A total of sixty-six subjects were randomly assigned into validation (n 44) and cross-validation (n 22) groups. All subjects performed fourteen activities while wearing a triaxial accelerometer in a controlled laboratory setting. During each activity, energy expenditure was measured by indirect calorimetry, and physical activity intensities were expressed as metabolic equivalents (MET). The validation group displayed strong relationships between measured MET and filtered synthetic accelerations for household (r 0·907, P < 0·001) and locomotive (r 0·961, P < 0·001) activities. In the cross-validation group, two GRPACA-based linear regression models provided highly accurate MET estimation for household and locomotive activities. Results were similar when equations were developed by non-linear regression or sex-specific linear or non-linear regressions. Sedentary activities were also accurately estimated by the specific linear regression classified from other activity counts. Therefore, the use of a triaxial accelerometer in combination with a GRPACA permits more accurate and immediate estimation of daily physical activity intensities, compared with previously reported cut-off classification models. This method may be useful for field investigations as well as for self-monitoring by general users.
The chemical composition, antioxidant activity, and antimicrobial properties of three commercially available essential oils: rosemary (REO), lavender (LEO), and mint (MEO), were determined in the ...current study. Our data revealed that the major components of REO, MEO, and LEO were 1,8-cineole (40.4%), menthol (40.1%), and linalool acetate (35.0%), respectively. The highest DPPH radical-scavenging activity was identified in MEO (36.85 ± 0.49%) among the investigated EOs. Regarding antimicrobial activities, we found that LEO had the strongest inhibitory efficiencies against the growth of Pseudomonas aeruginosa and Candida (C.) tropicalis, MEO against Salmonella (S.) enterica, and REO against Staphylococcus (S.) aureus. The strongest antifungal activity was displayed by mint EO, which totally inhibited the growth of Penicillium (P.) expansum and P. crustosum in all concentrations; the growth of P. citrinum was completely suppressed only by the lowest MEO concentration. The lowest minimal inhibitory concentrations (MICs) against S. enterica, S. aureus, and C. krusei were assessed for MEO. In situ analysis on the bread model showed that 125 µL/L of REO exhibited the lowest mycelial growth inhibition (MGI) of P. citrinum, and 500 µL/L of MEO caused the highest MGI of P. crustosum. Our results allow us to make conclusion that the analysed EOs have promising potential for use as innovative agents in the storage of bakery products in order to extend their shelf-life.
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