Application of microscopy and spectroscopy in investigating anti-cancer potential of Achyranthes aspera L. leaves.

The genus Achyranthes belong to the family Amaranthaceae which constitutes an important group of herbs and shrubs with immense medicinal value. The present research work was conducted to investigate the anticancer potential of Achyranthes aspera L. leaves by focusing on the antioxidant, aniproliferative and antimitotic activities of leaf extracts. Plant extraction was carried out by soxhelt method with different solvents. Phytochemical characterization of the plants extracts using chemical methods identified the presence of cardiac glycosides, saponins, coumarins, proteins, tannins, flavonoids and triterpenes. Alkaloid was present in methanolic and ethanolic extract. High performance liquid chromatography showed presence of different concentration of myricetin, quercetin and kaempferol in different extracts with the highest concentration of myricetin (84.53 µg/mL) in n-butanolic extract. The extracts were then tested for antioxidant activity using 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging assay by spectrophotometric method. In DPPH radical scavenging assay, antioxidant activity of A. aspera ranged between 79.78 ± 0.034% and 58.63 ± 0.069%. Highest antioxidant activity was observed for methanolic extract and lowest for acetone. Antimitotic activity was determined by using Allium cepa assay in which microscopic investigation was carried out to observe normal and abnormal phases of mitosis. In this assay, n-butanolic extract had highest antimitotic activity with minimum mitotic index at 2 mg/mL (57 ± 0.0351%). The plant extracts also caused chromosomal and mitotic aberrations which were clearly observed under 40× and 100× magnification of compound microscope. Antiproliferative activity was determined by using yeast cell model in which light microscope with hemocytometer was used for cell counting. In case of Antiproliferative activity, the ethyl acetate extract of A. aspera had highest antiproliferative activity with lowest cell viability (22.14 ± 0.076%) at highest extract concentration (2 mg/mL) while methanol extract of A. aspera had highest antiproliferative activity with lower cell viability (24.24 ± 0.057%) at lowest extract concentration (0.25 mg/mL). The results of the study indicated that the leaves extract of A. aspera have strong potential to be used as a source of anti-cancer agent. RESEARCH HIGHLIGHTS: Achyranthes aspera L. leaves have various phytochemicals which contribute to its medicinal properties Various extracts of the leaves of A. aspera L. possess antioxidant, antimitotic and antiproliferative potential The results of the study indicated that the leaves extract of A. aspera have strong potential to be used as a source of anti-cancer agent.

Herbivory and nutrients shape grassland soil seed banks.

Anthropogenic nutrient enrichment and shifts in herbivory can lead to dramatic changes in the composition and diversity of aboveground plant communities. In turn, this can alter seed banks in the soil, which are cryptic reservoirs of plant diversity. Here, we use data from seven Nutrient Network grassland sites on four continents, encompassing a range of climatic and environmental conditions, to test the joint effects of fertilization and aboveground mammalian herbivory on seed banks and on the similarity between aboveground plant communities and seed banks. We find that fertilization decreases plant species richness and diversity in seed banks, and homogenizes composition between aboveground and seed bank communities. Fertilization increases seed bank abundance especially in the presence of herbivores, while this effect is smaller in the absence of herbivores. Our findings highlight that nutrient enrichment can weaken a diversity maintaining mechanism in grasslands, and that herbivory needs to be considered when assessing nutrient enrichment effects on seed bank abundance.

[Responses of intraspecific and interspecific variations of plant functional traits to grazing in degraded grassland]. / é€€åŒ–è‰åœ°ç‰©ç§ç§å† å’Œç§é—´åŠŸèƒ½æ€§çŠ¶å˜å¼‚å¯¹æ”¾ç‰§çš„å“åº”.

Understanding the responses of functional trait variation for grassland plants to grazing disturbance is highly helpful to clarify the community assembly mechanism, functional diversity maintenance, plant adaptation and their strategies. We investigated plant functional traits (plant height, root length, leaf area, root area, leaf dry matter content, shoot dry matter content, root dry matter content, specific leaf area, specific root length and root/ shoot ratio) and the responses of their variation characteristics to grazing disturbance in enclosure and grazing grasslands in Horqin Sandy Land. The results showed that the interspecific variation of functional trait was obviously higher than the intraspecific variation in degraded grassland. The relative contribution of interspecific variation to the overall trait variation ranged from 70.2% to 95.1%, while that of intraspecific variation only contributed 4.9% to 29.8%. However, that did not imply the intraspecific variation could be ignored in the community assembly. The interspecific variation in grazing grassland was lower than that in enclosed grassland, while the intraspecific variation increased but the interspecific variation decreased in grazing grassland. Grazing resulted in the decrease of leaf area and leaf dry matter content but the increase of specific root length for pastoral-resistant grasses. However, pastoral-tolerant forbs would improve their dominance in the community by decreasing specific root length and increa-sing leaf area and leaf dry matter content. The traits sensitive to grazing were leaf area, leaf dry matter content, specific root length, and specific leaf area. Leaf traits and root traits were significantly positively correlated within and with each other. Grazing would enhance the synergy of root traits while reduce the synergy of leaf traits. That meant grazing could change the trade-off strategy of functional traits in individual and population levels, and thus affect vegetation structure and function in community level.

Effect of activator/precursor mass ratio on sulfur-doped porous carbon for catalytic oxidation of aqueous organics with persulfate.

Sulfur-doped porous carbon has emerged as promising metal-free catalysts toward persulfate (PS) for catalytic oxidation of aqueous organics. Wherein, thermal pyrolysis with activator activation is very common for the preparation of activated carbon. However, the relationship between the mass ratio of activator/precursor and catalytic efficiency has been rarely reported. Herein, a series of sulfur-doped porous carbons (S-AC) were synthesized by one-step chemical activation of (Poly(phenylene sulphide) (PPS)) with K2CO3 as activator at K2CO3/PPS mass ratio ranging from 0 to 3. The effects of K2CO3/PPS mass ratio on its physicochemical properties and its catalytic performance for p-chlorophenol (PCP) degradation with PS were comprehensively investigated. Experiment results show that sulfur doping enhanced its catalytic activity and the sample synthesized with K2CO3/PPS mass ratio of 2 (S-AC-2) exhibited the best adsorption and catalytic performance toward PS for PCP removal. More importantly, S-AC-2 with PS could efficiently degrade various aqueous toxic organics other than PCP, and S-AC-2 showed superior catalytic activity to many recently reported advanced materials. In addition, the effects of several operate parameters, including reaction temperature, PS concentration, pH, humic acid, and inorganic ions on PCP oxidation were evaluated. By combining with the results of quenching experiments and EPR, the PS activation mechanism over S-AC-2 was revealed. Moreover, the reusability and regenerability of S-AC-2 was also studied. It indicates that S-AC-2 showed inferior reusability, but the catalytic activity of which could be fully recovered through thermal treatment at 600 °C for 2 h in N2.

Senecavirus A Entry Into Host Cells Is Dependent on the Cholesterol-Mediated Endocytic Pathway.

Senecavirus A (SVA), an important member of the Picornaviridae family, causes vesicular disease in pigs. Here, we generated an EGFP-expressing recombinant SVA re-SVA-EGFP, which exhibited similar growth kinetics to its parental virus. The reporter SVA was used to study the role of pig ANTXR1 (pANTXR1) in SVA infection in a porcine alveolar macrophage cell line (PAM-Tang cells). Knockdown of the pANTXR1 significantly reduced SVA infection and replication in PAM-Tang cells, while re-expression of the pANTXR1 promoted the cell susceptibility to SVA infection. The results indicated that pANTXR1 is a crucial receptor mediating SVA infection. Subsequently, the viral endocytosis pathways for SVA entry into pig cells were investigated and the results showed that cholesterol played an essential role in receptor-mediated SVA entry. Together, these results demonstrated that SVA entered into host cells through the pANTXR1-mediated cholesterol pathway. Our findings provide potential targets to develop antiviral drugs for the prevention of SVA infection in the pig population.

CRISPR-Cas13d Exhibits Robust Antiviral Activity Against Seneca Valley Virus.

In recent years, Seneca Valley virus (SVV) as a newly identified pathogen of porcine vesicular disease spread quickly and has posed a potential threat to the swine industry in several countries resulting in economic losses. Considering the evolution of SVV, attention should be given to controlling SVV epidemics. So far there are no commercial vaccines or drugs available to combat SVV. Therefore, development of strategies for preventing and controlling SVV infection should be taken into account. In the current study, we evaluated whether the CRISPR-Cas13d system could be used as a powerful tool against SVV infection. Besides, selected crRNAs showed different capacity against SVV infection. Our study suggests the CRISPR-Cas13d system significantly inhibited SVV replication and exhibited potent anti-SVV activity. This knowledge may provide a novel alternative strategy to control epidemics of SVV in the future.

[Spatial distribution pattern and allometric growth of three common species on moving sand dunes in Horqin Sandy Land, China].

Research on fine scale pattern and characteristics of allometric growth could contribute to better understanding plants' adaptation in moving sandy dunes. The abundance, height and biomass of 3 species Agriophilum aquarrosum, Corispermum candelabrum and Setaria viridis in twenty-eight 1 m x 1 m quadrats of Horqin Sandy Land were identified, mapped and described. The nearest neighbor method and O-ring O(r) function analysis were applied to analyze the spatial patterns. The results showed that the individual spatial pattern was mainly aggregated in 1 m x 1 m quadrat at community level but mainly random at population level. At 0-50 cm individual distance scale, both intraspecific and interspecific relationship were facilitation and aggregated distribution occurred at some scales and varied with increasing plant abundance in 1 m x 1 m quadrat. In 0-40 cm, the aggregated distribution of S. viridis and A. aquarrosum increased obviously; in 10-20 cm, both intraspecific and interspecific aggregation increased; in 10-30 cm, the occurrence possibility of positive correlations between S. viridis and A. aquarrosum, S. viridis and C. candelabrum all increased; in 40-50 cm, the possibility of positive correlations between A. squarrosum and S. viridis, A. squarrosum and C. candelabrum all increased. Research on the three species components indicated that the growth rate of above-ground was faster than that of underground. S. viridis had the highest ratio of under-ground biomass to above-ground biomass but its nutritional organs' biomass ratio was medium. C. candelabrum allocated more biomass to propagative organs and stem, but A. squarrosum allocated more biomass to nutritional organs. Based on the spatial distribution and allometric characteristics, the three common species in moving sand dunes preferred r strategy in their life history.