Activated carbon adsorption is a promising technique for treatment of low-concentration heavy metal pollutants with high efficiency, simple operation, and flexibility; however, the cost of commercial ...activated carbon is too high. Therefore, much attention has been paid to activated carbon derived from low-cost agricultural and forest wastes. In this work, adsorption of Cd and Pb in aqueous solutions were conducted through batch experiments using
Typha angustifolia
carbon (TC) and
Salix matsudana
carbon (SC) prepared by phosphoric acid activation, and the adsorbents were characterized using SEM, FTIR, XPS, elemental analyzer, BET surface area, and zeta potential measurements. Both TC and SC mainly encompassed mesopores and bonds of O-H, C-O, C&z.dbd;O, and P&z.dbd;O/P-O-C. The BET surface area and isoelectric point (pH
IEP
) of TC and SC was 130.42 and 234.42 m
2
g
−1
and 3.45 and 4.38, respectively. The adsorption capacity of Cd and Pb for TC and SC both relied positively on the pH and humic acid but negatively on NaCl in the media. The adsorption process was spontaneous and endothermic, involved physicochemical reactions, and fitted well with the pseudo second-order and Langmuir models. Both the intraparticle diffusion and the chemical reaction were the rate limiting steps during adsorption. The maximum sorption capacity of Cd and Pb was 48.08 and 61.73 mg g
−1
(TC) and 40.98 and 58.82 mg g
−1
(SC), respectively, at pH 5 and 25 °C. The adsorption-desorption results showed that both activated carbons had good regeneration and reusability properties. The results suggested that both TC and SC had potential applications in the removal of Cd and Pb from aqueous solutions.
H
3
PO
4
activated
Typha angustifolia
and
Salix matsudana
carbons provide good adsorption/desorption characteristics for Cd and Pb.
The application of spermidine could effectively elevate the biomass and tolerance of Salix matsudana to Pb by promoting Pb accumulation in roots and the levels of spermidine and antioxidative system ...in leaves.
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•Salix matsudana could accumulate a high concentration of Pb in roots.•Exogenous spermidine promoted the Pb enrichment in roots in S. matsudana.•Spermidine reduced the levels of H2O2, MDA, O2−, and putrescine.•Spermidine elevated the antioxidant, spermidine, soluble protein, and nitric oxide levels.•Spermidine enhanced the S. matsudana tolerance to Pb.
The protective role of spermidine addition in media to Salix matsudana exposed to Pb was investigated by a hydroponic experiment in this study. The application of spermidine enhanced the biomass of S. matsudana exposed to Pb. Pb induced an increase in Pb levels in all organs of S. matsudana with the order of roots (maximum of 27616.0mg/kg DW)>cuttings>twigs>leaves. Exogenous spermidine promoted the accumulation of Pb in the roots, but inhibited the Pb translocation to the shoots and thus the Pb content in the twigs and leaves. The Pb-induced decrease in the concentrations of spermidine, soluble protein, and nitric oxide was elevated by the application of spermidine in the leaves of S. matsudana. Exogenous spermidine could also effectively up-regulate the antioxidative capacity and reduced the accumulation of superoxide anion, hydrogen peroxide, malondialdehyde, and putrescine. The results suggested that S. matsudana could accumulate a high level of Pb in the roots, and exogenous spermidine could enhance S. matsudana tolerance to Pb by the synergistic promotion of Pb accumulation in the roots and the levels of spermidine, nitric oxide, and antioxidants in the leaves.
In this study, exogenous spermidine role on Salix matsudana tolerance to cadmium was evaluated. Spermidine and cadmium presented antagonistic effects on the biomass, copper and zinc concentrations in ...S. matsudana. cadmium mainly distributed in the cell wall of subcellular fraction; 46.97%-60.43% of cadmium existed in a sodium chloride-extracted form. Cadmium contents in roots, leaves, and twigs ranged from 2002.67 to 3961.00, 111.59 to 229.72, and 102.56 to 221.27 mg/kg, respectively. Spermidine application elevated cadmium concentrations in the roots, cuttings, and cell wall and the ratio of deionized water-extracted cadmium, but decreased cadmium levels in the twigs and leaves and the fractions of cadmium extracted by ethanol and sodium chloride, respectively. Putrescine and malondialdehyde were important indicators of cadmium-induced oxidative damage. Exogenous spermidine alleviated the accumulation of superoxide anion, hydrogen peroxide, malondialdehyde via promoting the levels of spermidine, soluble protein, superoxide dismutase, reductive ascorbate, glutathione reductase, and glutathione peroxidase in S. matsudana leaves under the corresponding cadmium stress. The results indicated that S. matsudana was a candidate for cadmium rhizoremediation and extraction in leaves; the spermidine application enhanced the cadmium tolerance of S. matsudana through promoting cadmium accumulation in roots, cell wall, and less bioactive chemical forms and the antioxidative ability.
Increasing evidence highlights the cardinal role of gut microbiota in tumorigenesis and chemotherapy outcomes. Paclitaxel (PTX), although as a first-line chemotherapy reagent for breast cancer, still ...requires for improvement on its efficacy and safety due to drug resistance and adverse effects. The present work explored the enhancement of a polysaccharide derived from spore of
(SGP) with PTX in a murine 4T1-breast cancer model. Results showed that the combination of PTX and SGP displayed an improved tumor control, in which mRNA expression of several Warburg effect-related proteins, i.e., glucose transporter 3 (
), lactate dehydrogenase A (
), and pyruvate dehydrogenase kinase (
), and the metabolite profile of tumor was evidently altered. Flowcytometry analysis revealed that the combination treatment recovered the exhausted tumor infiltration lymphocytes (TILs) via inhibiting the expressions of immune checkpoints (PD-1 and Tim-3), while PTX alone evidently increased that of CTLA-4. 16S rRNA sequencing revealed a restoration by the combination treatment on gut microbiota dysbiosis induced by PTX, especially that
, and other 5 genera were significantly enriched while the cancer-risk genera,
and
, were decreased. Moreover, spearman correlation analysis showed that abundance of
was significantly negative-associated with the amount of frucotose-6-phosphate within the tumor. Collectively, the present study suggests the clinical implication of SGP as an adjuvant candidate for PTX against breast cancer, which possibly relies on the regulation of tumor metabolism and gut microbiota.
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