Natural fermentation of plant tissues as environmental remediation materials to improve soil and enhance plant resistance to cadmium stress

Cadmium (Cd) pollution poses a serious threat to various ecosystems, and phytoremediation is an alternate method for developing the soil health. To better utilize phytoremediation for Cd-contaminated soil remediation, the ginkgo leaves, pine needles, and Eucommia bark were mixed and naturally fermented to obtain Ginkgo biloba–Pinus massoniana–Eucommia ulmoides (GPE) Jiaosu and Jiaosu residue, whose effects on Broussonetia papyrifera planted in Cd-contaminated soil were evaluated. The results showed that the contents of the protein, phenolic, vitamin E, and alcohol of GPE Jiaosu were 4400 ± 0.46, 0.22 ± 0.01, 0.88 ± 0.24, and 4.63 ± 0.25 μL/mL, accordingly, with fine antioxidant activity. The soil pH, electrical conductivity content, organic carbon, total nitrogen, total phosphorus, alkali-hydrolyzable nitrogen, available phosphorus, and Cd concentration were all significantly (p < 0.05) modified. The chlorophyll content of B. papyrifera was increased by using Jiaosu residue in 12 hours, while the promotion effect of Jiaosu appeared in the later stage (60 days). The Cd tolerance physiological indexes such as malondialdehyde content and antioxidant enzymes' activity were all regulated. Applying the Jiaosu residue, the Cd in stems was decreased by 72.61% under 1000 mg/kg Cd treatment. These results suggested that GPE Jiaosu and Jiaosu residue can improve the properties of Cd-contaminated soil, promote the Cd tolerance of B. papyrifera, and affect the Cd migration. The current study provides a new bioremediation method using the Jiaosu and Jiaosu residue as Cd environmental remediation materials in a recyclable pathway, which is a circular and healthy development concept that integrates economic, ecological, and social significance.     

Phytoplankton community structure of a deep subalpine Italian Lake (Lake Orta,N. Italy) four years after the recovery from acidification by liming

The phytoplankton succession in Lake Orta, heavy metals and ammonium polluted for decades and subjected to liming intervention in 1989–90, was studied during 1994. The existence of three main succession stages, with different structures of the community emerged. Chlorophyta are the most important taxonomic group in every season. The spring community was dominated by chlorophytes, Dinobryon sertularia and Kephyrion sp., the summer by Synedra sp. and Westella botryoides, the autumn by Rhizosolenia eriensis and W. botryoides, the winter by Synedra sp., R. eriensis and Synechococcus sp. The abundance of Chlorophyta, less important in other deep subalpine lakes, and the dominance of taxa able to thrive in polluted environments, could be related to the presence of trace metals in the sediments.     

Unique single‐domain antigen binding fragments derived from naturally occurring camel heavy‐chain antibodies

The humoral immune response of camels, dromedaries and llamas includes functional antibodies formed by two heavy chains and no light chains. The amino acid sequence of the variable domain of the naturally occurring heavy‐chain antibodies reveals the necessary adaptations to compensate for the absence of the light chain. In contrast to the conventional antibodies, a large proportion of the heavy‐chain antibodies acts as competitive enzyme inhibitors. Studies on the dromedary immunoglobulin genes start to shed light on the ontogeny of these heavy‐chain antibodies. The presence of the heavy‐chain antibodies and the possibility of immunizing a dromedary allows for the production of antigen binders consisting of a single domain only. These minimal antigen‐binding fragments are well expressed in bacteria, bind the antigen with affinity in the nM range and are very stable. We expect that such camelid single domain antibodies will find their way into a number of biotechnological or medical applications. The structure of the camelid single domain is homologous to the human VH, however, the antigen‐binding loop structures deviate fundamentally from the canonical structures described for human or mouse VHs. This has two additional advantages: (1) the camel or llama derived single domain antibodies might be an ideal scaffold for anti‐idiotypic vaccinations; and (2) the development of smaller peptides or peptide mimetic drugs derived from of the antigen binding loops might be facilitated due to their less complex antigen binding site. Copyright © 1999 John Wiley & Sons, Ltd.     

Trace Metal Bioaccumulation in Epibenthic Macroinvertebrates (EMI) from the San Pedro Shelf,California

Trace metal/metalloid (As, Ag, Cd, Cr, Cu, Hg, Ni, Pb, Se, Zn) bioaccumulation was measured over a period of ten years (1985–1995) in five species of epibenthic macroinvertebrates (EMI) from the San Pedro Shelf, California. Four of the species are numerical dominants in the Southern California Bight (SCB) and two species are commercially harvested. Among three echinoderms, a predatory sea star yielded highest tissue concentrations compared to a sea cucumber and a sea urchin, and concentrations measured in a mantid shrimp exceeded those from a prawn. Comparison of trace metal bioaccumulation from the study area, including the ocean outfall, and elsewhere indicated that bioaccumulation in local EMI was generally low. Measurements from an outfall station and two reference stations were used to evaluate the spatial and temporal relationship between trace metal bioaccumulation and the wastewater discharge. It was concluded that there was no spatial or temporal relationship between EMI trace metal bioaccumulation and the discharge.     

The futuristic applications of transition metal dichalcogenides for cancer therapy

The second-most common cause of death resulting from genetic mutations in DNA sequences is cancer. The difficulty in the field of anticancer research is the application of the traditional methods, which also affects normal cells. Mutations, genetic replication alterations, and chromosomal abnormalities have a direct impact on the effectiveness of anticancer drugs at different stages. Presently, therapeutic techniques utilize nanotechnology, transition metal dichalcogenides (TMDCs), and robotics. TMDCs are being increasingly employed in tumor therapy and biosensing applications due to their biocompatibility, adjustable bandgap, versatile functionality, exceptional photoelectric properties, and wide range of applications. This study reports the advancement of nanoplatforms based on TMDCs that are specifically engineered for responsive and intelligent cancer therapy. This article offers a thorough examination of the current challenges, future possibilities for theranostic applications using TMDCs, and recent progress in employing TMDCs for cancer therapy. Currently, there is significant interest in two-dimensional (2D) TMDCs nanomaterials as ultrathin unique physicochemical properties. These materials have attracted attention in various fields, including biomedicine. Due to their inherent ability to absorb near-infrared light and their exceptionally large surface area, significant efforts are being made to prepare multifunctional nanoplatforms based on 2D TMDCs.     

Local Steric Hindrance for CO2 Electroreduction at a Thermodynamic Potential and Wide Working Window

To improve the energy-conversion efficiency and adaptability between a CO₂ electroreduction system and intermittent renewable energy, small onset potentials, and wide working windows are highly important. Here, three indium metal–organic frameworks (In-MOFs) have been projected using different ligands to adjust the local steric hindrance and electronic structure of In nodes, manipulating the whole workflow of CO₂ during electroreduction including local CO₂ transport, adsorption, activation, hydrogenation, and product desorption. Significantly, a CO₂ electroreduction to formate process promoted by 2,5-TDC In-MOF shows an onset potential of −0.1 V versus RHE around the therymodynamic potential, over 90% FE_foramte in a wide current-density window from 0.1 to 0.9 A cm⁻². Driven by solar cells, the system displays a high solar-to-chemical efficiency of 17.39%. In depth mechanism study indicates that the local CO₂ transport and adsorption of all In-MOFs are thermodynamically and kinetically favorable, while the energy barrier of potential-determine step (*HCOOH desorption) is the lowest for 2,5-TDC In-MOF.     

6种重金属对赤子爱胜蚓的急性毒性效应与风险评价

【背景】近年来,土壤重金属污染问题日益凸显,对生态环境、食品安全和人体健康构成了严重威胁,其急性毒性尚未明确。【方法】采用滤纸接触法和人工土壤法测定了铜(Cu2+)、锌(Zn2+)、镍(Ni+)、镉(Cd2+)、铅(Pb2+)和锰(Mn2+)等6种重金属对赤子爱胜蚓的急性毒性效应,并参照欧盟指令91/414/EEC标准评价了其环境风险。【结果】滤纸接触法48h测定结果表明,6种重金属对蚯蚓的LC50为3.17(2.53～3.81)～90.42(69.45～140.47)μg.cm-2,其毒性次序为Cu2+>Zn2+>Ni+>Cd2+>Pb2+>Mn2+。人工土壤法14d测定结果表明,6种重金属对蚯蚓的LC50为1347(1236～1453)～6936(6144～8930)mg.kg-1,其毒性次序为Cu2+>Cd2+>Ni+>Zn2+>Mn2+>Pb2+。风险评价结果显示,Cu2+、Zn2+、Ni+、Cd2+、Pb2+和Mn2+等6种重金属的暴露比(toxicity/exposureratio,TER)分别为3.37、4.46、8.68、1428、13.87和5.85。【结论与意义】6种重金属对土壤动物蚯蚓均具有潜在的毒性效应。Cu2+、Zn2+、Ni+、Mn2+等4种重金属对赤子爱胜蚓存在急性毒性风险,而Cd2+和Pb2+对赤子爱胜蚓的急性毒性风险水平是可接受的。该评价结果可为我国制定基于风险的土壤环境质量标准提供依据。     

固体介质中的重金属源解析及其在中国近海沉积物中的应用

沉积物中重金属源解析对甄别人为活动与自然变化对近海生态系统演化的影响有重要作用.本文总结了近年来污染物源解析常用的多元统计分析、地球化学方法和地质统计分析3种主要研究方法,剖析了不同方法的优劣及适用性,提出正定矩阵因子分析、Pb同位素示踪在重金属来源定量化研究中具有良好应用前景.梳理了中国近海沉积物中重金属来源的主要研究结果,发现河口和海湾是沉积物重金属受人为来源影响剧烈的典型近海区域,不同定量解析方法(多元统计分析、背景值估算、Pb同位素分析)均表明中国近海沉积物重金属的人为来源贡献率接近或超过50%.当前中国近海沉积物中重金属源解析研究还存在源识别端元模糊、解析结果缺乏相应的可靠性评价等问题.据此提出近海沉积物重金属源解析研究应使用多种解析技术手段综合、集成与优化,提高源解析的准确性;建立完善指标体系,筛选代表特定人为活动和自然过程的指标;甄别人为源重金属入海方式及过程,为沉积物数据信息的解译提供理论基础.     

Copper(II), cobalt(II) and nickel(II) complexes of lapachol: synthesis,DNA interaction,and cytotoxicity

Three novel copper(II), cobalt(II), and nickel(II) complexes of lapachol (Lap) containing 110-phenanthroline (phen) ligand, [M(Lap)₂(phen)] (M=Cu(II), 1, Co(II), 2, and Ni(II), 3), have been synthesized and characterized using, elemental analysis and spectroscopic studies. Their interactions with calf thymus DNA (CT DNA) were investigated using viscosity, thermal denaturation, circular dichorism, fluorescence quenching, and electronic absorption spectroscopy. The DNA cleavage abilities of 1–3 have been studied, where cleavage activity of copper complex 1 is more than the complexes 2 and 3. The in vitro cytotoxic potential of the complexes 1–3 against human cervical carcinoma (HeLa), human liver hepatocellular carcinoma (HepG-2), and human colorectal adenocarcinoma (HT-29) cells indicated their promising antitumor activity with quite low IC₅₀ values in the range of .15–2.41 μM, which are lower than those of cisplatin.