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Malignant tumors have become one of the challenges to global human health today, and the development of new drugs has become a research hotspot for tumor treatment. In order to prove that copper(II)-thiosemicarbazone complexes can be used as antibacterial and antitumor agents, we have synthesized and characterized three copper(II) complexes (C1-C3). These Cu(II) complexes exhibited excellent anticancer and antimicrobial activity, and greatly exceed the corresponding metal-free ligands. C3 has the highest anti-proliferative activity (0.20 ± 0.04 µM) against A549 (human lung carcinoma cell lines) and the best inhibitory zone diameter (25.78 ± 0.18 mm) against E. coli. The lipophilicity of the ligand is closely related to the anti-proliferative and antibacterial activities of these Cu(II) complexes. The study of the cellular mechanism demonstrates that these Cu(II) complexes promoted cell apoptosis by catalyzing hydrogen peroxide to produce intracellular reactive oxygen species (ROS). Antibacterial experiments showed that these Cu(II) complexes exhibited potent antibacterial activities, especially against gram-negative bacteria. These Cu(II) complexes may initially cause outer membrane/lipopolysaccharide (LPS) instability, disrupt cell membranes, and ultimately lead to bacterial cell lysis.

An ultrasensitive photochemical biosensor based on the target miRNA-triggered catalytic hairpin assembly (CHA) reaction between Au nanoparticles (AuNPs)/C

A series of small molecule dyes demonstrate the feasibility of manipulating Near Infrared II emission by simply altering the donors' heteroatoms, which involved both electronegativity and intramolecular steric effects. Furthermore, these dyes show high resolution and stability for in vivo imaging after being complexed with human serum albumin.

Taking a composite of a nanomaterial and a signal molecule as a substrate material can provide a label-free electrochemical platform. Besides, the nanomaterial with a high catalytic activity towards the signal molecule can improve the sensitivity of the platform. Herein, a thionine functionalized Fe–N–C nanocomposite was employed as the substrate. Firstly, the electrocatalytic activity of Fe–N–C towards the electroreduction of thionine was explored. Then, an immobilization-free and label-free electrochemical platform for the determination of microRNA-21 based on Fe–N–C–thionine/Fe3O4@AuNPs was constructed. A magnetic glassy carbon electrode (MGCE) was used to keep the magnetic Fe–N–C–thionine/Fe3O4@AuNPs modified onto the surface of the MGCE. Fe–N–C and Fe3O4 nanoparticles can co-catalyze the electroreduction of thionine and a strong electrochemical reduction signal of thionine could be realized in the differential pulse voltammetry (DPV) test. Also, a catalytic hairpin assembly (CHA) reaction was utilized to enhance the sensitivity of the developed electrochemical biosensor. Besides, the developed biosensor shows excellent specificity and reproducibility in the test of human serum samples, indicating its wide application prospects in the early-stage diagnosis of tumors.

In this work, we report AuNPs-decorated pyrolyzed Co-BDC nanosheets (p-Co-BDC/AuNPs) as high-performance electrocatalyst for developing an electrochemical platform. p-Co-BDC/AuNPs as a new electrocatalyst showed superior electrocatalytic activity towards the electrochemical oxidation of methylene blue (MB). Besides, magnetic p-Co-BDC/AuNPs can be well immobilized on the magnetic glassy carbon electrode without further assistance. The oxidation of MB can be reduced by ascorbic acid. Inspired by this phenomenon, an electrochemical biosensor was constructed based on multiple signal amplification for the diagnosis of miRNAs. Firstly, p-Co-BDC/AuNPs enhanced the electrochemical oxidation of MB. Then, strand displacement amplification reaction can form lots of double helix structure DNA to embed more MB molecules. Finally, ascorbic acid in the electrolyte was utilized to reduce the oxidation of MB and improve the electrochemical signal of MB electro-oxidation. The linear detection range for the detection of miRNAs is 100 aM to 10 nM, and the limit of detection is 86 aM. Furthermore, the constructed biosensor also displayed satisfactory selectivity, good reproducibility, and excellent recovery in the detection of real samples. We are convinced that our proposed multiple signal amplification strategy will provide more promising methods for the diagnosis of cancer.

Precious metals are highly demanded economic value metals that require to be recovered from industrial wastes and electronic used products (e-waste). They are such as gold (Au) as well as Platinum Group Metals (PGMs) for instance palladium (Pd) and platinum (Pt). The study was conducted to test the magnetic iron oxide nanoparticles modified with Moringa oleifera seed proteins as adsorbent for recovery of Au(III), Pd(II) and Pt(IV) from aqueous solutions. Different functional groups responsible for adsorption, morphology, thermal stability, and surface charges of the nanoparticles were characterized with FTIR, SEM, TGA and Zeta potential respectively. Batch adsorption method was used, and precious metal ions percentage recovery was measured using ICP-OES. The effects of pH, initial adsorbate concentration, adsorption agitation time and adsorbent dosage were studied at room temperature of 25°C. Au(III) yielded a maximal recovery of 99.8%, followed by Pt(IV) with 87.7%, then Pd(II) with 72.7% at a pH 2.5, 10 mg/L initial adsorbate concentration, 120 minutes agitation time and 0.065 g adsorbent dosage. These results suggested that modified iron oxide nanoparticles were effective in selective recovery of the precious metal ions.

Bulbine frutescens, a plant native to southern Africa, is used traditionally in the management of conditions related to HIV/AIDS and to promote wound healing. This study investigated the in vitro anti-HIV and antioxidant potential of B. frutescens in order to determine its possible contribution to alleviating HIV/AIDS and its traditional success as a wound healing agent. The extract of the aerial parts of B. frutescens was tested for in vitro inhibitory activity on HIV-1 protease (PR), reverse transcriptase (RT) and integrase enzymes all of which have an essential role in the HIV replication cycle. Since antioxidants contribute to wound healing, the plant extract was studied for 2,2-diphenyl-1-picryl hydrazyl (DPPH), ferric reducing power and hydrogen peroxide (H2O2) scavenging activity. In addition, phytochemical analysis of the extract was conducted using standard procedures. The extract demonstrated good inhibitory activity against HIV-1 PR and RT with IC50 values of 0.18 ± 0.01 and 0.52 ± 0.03 mg/mL, respectively. It also demonstrated potent antioxidant activity with IC50 values of 17.94 ± 0.72 and 26.21 ± 0.39 μg/mL for DPPH and H2O2, respectively. The reducing power of B. frutescens extract was found to be concentration dependent. Qualitative phytochemical screening revealed the presence of phenols, alkaloids and flavonoids. The content of one of the major component detected, flavonoids, was 71.60 ± 0.05 mg QE/g extract. This study demonstrates that B. frutescens extract has anti-HIV potential and the traditional use of the plant as a wound healing agent could be through its high antioxidant activity.

The Schinziophyton rautanenii tree is an important food source for many communities of the African continent. Oil extracted from the Manketti nut is of great economic value, due to its unique composition and properties. In this study, the physical and chemical characteristics of the oil obtained from three extraction methods – cold pressed, traditional and Soxhlet extraction – were investigated and compared. Oil yield of the nut was found to be 42.6 ± 0.84%. Good quality characteristics, including saponification values (184–189 mg KOH/g), iodine values (120–131 g/100 g), acid values (0.959–2.44 mg KOH/g) and peroxide values (1.80–3.98 meqO2/kg) were found for the Manketti nut oil. The total tocopherol content was in the range of 144–206 mg/100 g of oil, with γ-tocopherol as the dominant tocopherol. The oil was rich in conjugated fatty acids, α-eleostearic (9Z,11E,13E-octadecatrienoic acid) (24–36%) and linoleic acid (9Z,12Z-octadeca-9,12-dienoic acid) (31–32%), making it a potential candidate in the nutraceutical and cosmetics industry.

Moringa oleifera Lam. belongs to the family Moringaceae, and is predominantly found in India and tropical and arid countries, including Namibia. The different plant parts of the tree have been subject to extensive research for many years due to the beneficial properties and applications in the medicinal, food, and fuel industries. The oil content of the seed is about 11%–62%, and when pressed, produces a yellow oil with a peanut-like flavor. The oil has been reported to contain 34–515 mg/kg of total tocopherols with oleic acid (C18:1) as the major fatty acid (70%–79%). Good thermal and oxidative stability is imparted on the oil by the high oleic acid concentration and tocopherols, which makes the oil a suitable candidate for frying and cooking. The additional presence of high concentrations of campesterol, □-sitosterol, stigmasterol, and Δ5-avenasterol make the oil a suitable raw material for the nutraceutical industry. This chapter describes the properties, composition, health-promoting traits, and other applications of cold pressed M. oleifera seed oil.

Small molecule 5BMF is a novel mitochondria-targeted delocalized lipophilic cation (DLC) with good anti-tumor activity and fluorescence emission suitable for bioimaging. In this study, human serum albumin (HSA) complexed with 5BMF (5BMF@HSA) has been developed to further improve its solubility (from 1.61 to 5.41 mg/mL), and the fluorescent intensity of 5BMF@HSA was improved over 2 times. Nearly 10-fold 5BMF was released from 5BMF@HSA complex in acidic condition when compared with neutral/basic environment. Intracellular distribution of 5BMF was altered by HSA as its signals were observed in lysosomes where free 5BMF barely localized. Both 5BMF@HSA and 5BMF showed selective toxicity toward tumor cells in μM and nM range and effectively inhibited tumor growth in mice model. In summary, 5BMF@HSA shows improved solubility in aqueous buffer and enhanced fluorescence emission, and maintains tumor inhibition capability. It is a promising protein complex for tumor cell imaging and tumor treatment.

Hexavalent chromium, Cr(VI), is a toxic metal present in industrial effluents. The study was carried to test the use of green Moringa leaves biomass as adsorbent for Cr(VI) from aqueous solutions. Batch adsorption method was used and the concentration of Cr(VI) measured using an ultraviolet-visible (UV-Vis) spectrophotometry. The effects of the adsorption contact time, adsorbent dosage, pH, initial adsorbate concentration and temperature were studied. Results show maximum removal of Cr(VI) of 99% ± 1%, with maximum adsorption capacity of 33.9 mg/g at a pH 2, 60 minutes contact time and 100 mg/l initial Cr(IV) concentration. The Langmuir and Freundlich adsorption isotherm models were used to fit the experimental data. The data showed that adsorption on green Moringa oleifera leaves tea biomass fitted well to Freundlich isotherm (r2 = 0.9432) compared to the Langmuir isotherm (r2 = 0.9122). M. oleifera leaves biomass can be used in water purification systems. The sludge of M. oleifera leaves is biodegradable, cost effective and environmentally friendly and therefore attractive in hexavalent chromium removal in water.

MicroRNAs (miRNAs) are becoming biomarkers for the clinical diagnosis of many diseases. However, their intrinsic properties such as low enrichment and short sequence restrict their applications. Here, we designed an ultrasensitive dual signal amplification electrochemical biosensor based on sodium alginate-polypyrrole/Au nanoparticles (SA-PPy/AuNPs) nanocomposite for the detection of miRNAs. Firstly, a planar intercalated copper(II) complex was synthesized to be the signal molecule. Then, catalytic hairpin assembly (CHA) reaction and catalytic reaction between ferric ion and copper ion were combined as a dual signal amplification to improve the sensitivity of the biosensor. In the presence of target miRNAs, multiple double helix structure formed for the CHA reaction was triggered, which immobilized more copper(II) complex on the surface of the working electrode and a strong signal was obtained in the square wave voltammetry (SWV) test. Also, the signal can be re-amplified again in the presence of ferric ion in the electrolyte. Under the optimal conditions, based on these strategies, a sensitive electrochemical biosensor was constructed for the detection of miRNAs in the range of 1 fM to 1 nM and the limit of detection was as low as 0.34 fM. Furthermore, the developed biosensor with excellent selectivity and reproducibility tested on human serum samples shows broad application prospects in the early stage of tumor diagnosis.

Latent HIV reservoirs in infected individuals prevent current treatment from eradicating infection. Treatment strategies against latency involve adjuvants for viral reactivation which exposes viral particles to antiretroviral drugs. In this study, the effect of novel triterpenoids isolated from Ocimum labiatum on HIV-1 expression was measured through HIV-1 p24 antigen capture in the U1 latency model of HIV-1 infection and in peripheral blood mononuclear cells (PBMCs) of infected patients on combination antiretroviral therapy (cART). The mechanism of viral reactivation was determined through the compound’s effect on cytokine production, histone deacetylase (HDAC) inhibition, and protein kinase C (PKC) activation. Cytotoxicity of the triterpenoids was determined using a tetrazolium dye and flow cytometry. The isolated triterpene isomers, 3-hydroxy-4,6a,6b,11,12,14b-hexamethyl-1,2,3,4,6,6a,6b,7,8,8a,9,10,11,12,12a,14,14a,14b-octadecahydropicene-4,8a-dicarboxylic acid (HHODC), significantly (p < 0.05) induced HIV-1 expression in a dose-dependent manner in U1 cells at non-cytotoxic concentrations. HHODC also induced viral expression in PBMCs of HIV-1 infected patients on cART. In addition, the compound up-regulated the production of interleukin (IL)-2, IL-6, tumour necrosis factor (TNF)-α, and interferon (IFN)-γ but had no effect on HDAC and PKC activity, suggesting cytokine upregulation as being involved in latency activation. The observed in vitro reactivation of HIV-1 introduces the adjuvant potential of HHODC for the first time here.

The physicochemical characteristics, fatty acid, tocopherol, stigmasterol, β-sitosterol, and 1H NMR profiles of Citrullus lanatus and Acanthosicyos horridus melon seed oils were determined and compared among different extraction methods (cold pressing, traditional, and Soxhlet). The oil content was 40.2 ± 3.45 and 37.8 ± 7.26% for C. lanatus and A. horridus, respectively. Significant differences (p

The physicochemical characteristics, fatty acid, tocopherol, stigmasterol, β-sitosterol, and 1H NMR profiles of Citrullus lanatus and Acanthosicyos horridus melon seed oils were determined and compared among different extraction methods (cold pressing, traditional, and Soxhlet). The oil content was 40.2 ± 3.45 and 37.8 ± 7.26% for C. lanatus and A. horridus, respectively. Significant differences (p

MicroRNAs (miRNAs) are important biomarkers in early diagnosis of disease. In this work, we developed a simple and effective electrochemical biosensor based on Au nanoparticles (AuNPs)/Carbon nitride nanosheet (CNNS) nanocomposite for the miRNAs detection. Duplex-specific nuclease (DSN) and hairpin structure probe were utilized to improve the sensitivity and selectivity respectively. In the presence of miRNA-21, the signal molecule could be released from the surface of the electrode and decrease the current peak in square wave voltammetry (SWV) test. Under the optimal conditions, the reported biosensor showed that the detection range of miRNA-21 is from 10 fM to 1 nM and detection limit is as low as 2.9 fM. Furthermore, the detection of miRNA-21 added in serum samples indicates the developed biosensor with good selectivity, stability and reproducibility which verify its potential to be used in the early diagnosis of diseases.

Geometric and electronic structures of Al 4 P − , Al 4 P, Ga 4 P − and Ga 4 P are studied using B3LYP-DFT and CCSD(T) methods with the 6-311+G(2d) and 6-311+G(2df) one-particle basis sets. The anions have similar square pyramidal (C 4v ) gas phase equilibrium geometry while the neutral species possess the trapezium (C 2v ) planar geometry in accordance with the predictions of Boldyrev and Wang [A.I. Boldyrev, L.S. Wang, J. Phys. Chem. A 105 (2001) 10759]. Electron detachment processes from the ground electronic states of the anions are presented and an attempt is made to assign the features observed in the anion photoelectron spectra of Al 4 P − and Ga 4 P − .

Tylosema esculentum(marama) beans and tubers are used as food, and traditional medicine against diarrhoea in Southern Africa. Rotaviruses (RVs) are a major cause of diarrhoea among infants, young children, immunocompromised people, and domesticated animals. Our work is first to determine anti-RV activity of marama bean and tuber ethanol and water extracts; in this case on intestinal enterocyte cells of human infant (H4), adult pig (CLAB) and adult bovine (CIEB) origin. Marama cotyledon ethanolic extract (MCE) and cotyledon water extract (MCW) without RV were not cytotoxic to all cells tested, while seed coat and tuber extracts showed variable levels of cytotoxicity. Marama cotyledon ethanolic and water extracts (MCE and MCW, resp.) (≥0.1 mg/mL), seed coat extract (MSCE) and seed coat water extract (MSCW) (0.01 to 0.001 mg/mL), especially ethanolic, significantly increased cell survival and enhanced survival to cytopathic effects of RV by at least 100% after in vitro co- and pre-incubation treatments. All marama extracts used significantly enhanced nitric oxide release from H4 cells and enhanced TER (Ω/cm2) of enterocyte barriers after coincubation with RV. Marama cotyledon and seed coat extracts inhibited virion infectivity possibly through interference with replication due to accumulation of nitric oxide. Marama extracts are therefore promising microbicides against RV.

Hoodia gordonii products are widely commercialized for anti-obesity purposes; however, minimal research is available on the other health properties demonstrated by this popular herbal plant. H. gordonii crude extracts (ethanol and ethyl acetate) were assayed for in vitro anti-HIV-1 protease (PR), reverse transcriptase (RT) and integrase activity. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power assays were used for the antioxidant analysis. In addition, qualitative and quantitative phytochemical analyses of the extracts were determined using standard methods. H. gordonii extract demonstrated good inhibition against HIV RT with IC50 values of 73.55 ± 0.04 and 69.81 ± 9.45 μg/mL for ethanol and ethyl acetate extracts, respectively. Both extracts also demonstrated inhibitory activity against HIV PR with IC50 values of 97.29 ± 0.01 and 63.76 ± 9.01 μg/mL for ethanol and ethyl acetate extracts. In addition, H. gordonii also showed good antioxidant activity with IC50 values of 124.6 ± 11.3 and 126.2 ± 3.15 μg/mL obtained for ethanol and ethyl acetate extracts, respectively. The reducing power of H. gordonii extracts increased as the concentration increased which confirmed the presence of antioxidants (reductants) in the extracts. Phytochemical screening of H. gordonii revealed the presence of phenolics, alkaloids, terpenes, steroids, cardiac glycosides and tannins in the ethanolic extract, while the ethyl acetate extract only showed the presence of phenolics, cardiac glycosides and steroids. The total phenolic content was 420 ± 0.17 and 319.9 ± 0.2 mg GAE/g for the ethanol and ethyl acetate extracts, respectively. The ethanol extract, which revealed the presence of tannins, had a tannin content of 330 ± 0.2 mg TAE/g extract. This data suggests that H. gordonii has good in vitro inhibition against selected HIV-1 enzymes as well as antioxidant properties, suggesting new potential uses for this commercial plant.