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[Display omitted] Improving ligand-to-active metal charge transfer (LAMCT) by finely tuning the organic ligand is a decisive strategy to enhance charge transfer in metal organic frameworks (MOFs)-based catalysts. However, in most MOFs loaded with active metal catalysts, electron transmission encounters massive obstacle at the interface between the two constituents owing to poor LAMCT. Herein, amines (–NH 2) functionalized MOFs (NH 2 -MIL-101(Cr)) encapsulated active metal Pt nanoclusters (NCs) catalysts are synthesized by the polyol reduction method and utilized for the photoreduction of CO 2. Surprisingly, the introduction of –NH 2 (electron donating) groups within the matrix of MIL-101(Cr) improved the electron migration through the LAMCT process, fostering a synergistic interaction with Pt. The combined experimental analysis exposed the high number of metallic Pt (Pt0) in Pt@NH 2 -MIL-101(Cr) catalyst through seamless electron shuttling from N of –NH 2 group to excited Pt generating versatile hybrid Pt-N catalytic centres. Consequently, these versatile hybrid catalytic centres act as electro-nucleophilic centres, which enable the efficient and selective conversion of C O bond in CO 2 to harvest CH 4 (131.0 µmol.g−1) and maintain excellent stability and selectivity for consecutive five rounds, superior to Pt@MIL-101(Cr) and most reported catalysts. Our study verified that the precise tuning of organic ligands in MOFs immensely improves the surface-active centres, electron migration, and catalytic selectivity of the excited Pt NCs catalysts encaged inside MOFs through an improved LAMCT pathway. [ABSTRACT FROM AUTHOR]

Abstract In order to ensure global food security a rationale approach is required to control all those factors which directly or indirectly affect the food productivity. The neglected helminthic diseases alone are responsible for huge economic losses to the agrarian stakeholders. The problem is further compounded by the emerging drug resistance in flukes against the commonly used anthelmintics like triclabendazole. Therefore, the search for alternatives including the nano-based approaches has become a necessity to develop future control strategies. In the present study the effect of biologically synthesized silver nanoparticles (AgNPs) was investigated on an economically important amphistome parasite, Gigantocotyle explanatum, obtained from the infected liver of the Indian water buffaloes, Bubalus bubalis. In vitro treatment of the adult worms with different doses of AgNPs severely affected the worm motility and caused ROS mediated damages in the treated flukes. The antioxidant system and the detoxification ability of the worms appeared to be disrupted along with pronounced DNA damage in the treated worms as compared to the controls. Following the treatment of worms with different concentrations of AgNPs there was a significant (p < 0.05) increase in lipid peroxidation and protein carbonylation levels which are the key oxidative stress markers. The tegumental surface which is metabolically active, was severely damaged as evident from the loss of papillae, severe blebbing, shearing and erosion of the surface structures. Such topographical disruptions would facilitate the penetration of the nanoparticles deep within the tissues that might greatly reduce the invasive potential of the flukes as evident from the decreased motility. Taken together our findings suggest that the AgNPs posses great anthelmintic potential and could be further exploited for the development of anthelmintic formulations which may be tested in vivo. Graphical abstract Image 1 Highlights • Anthelmintic effect of biologically synthesized AgNPs was studied on G. explanatum. • The AgNPs caused ROS mediated biochemical changes in treated worms. • The nanoparticles resulted in DNA damage and alteration in the polypeptide profile. • AgNPs also severely disrupted the tegument thus showing strong anthelmintic potential. [ABSTRACT FROM AUTHOR]

The emerging resistance against commonly used antiparasitic drugs has driven investigators to explore alternative approaches using plant-derived active ingredients. These compounds have been tested for antiviral, antibacterial, and anthelmintic properties, particularly against adult worms. However, their effects on larval forms have been neglected. Curcumin is a polyphenol that is a significant constituent of the rhizome of Curcuma longa and possesses various biological activities, including antioxidant, anti-inflammatory, anti-infectious, and anti-carcinogenic. In the present study, the anthelmintic potential of curcumin was tested in vitro for its efficacy against the zoonotically important larval form, the progenetic metacercariae of Clinostomum complanatum , which were procured from the forage fish, Trichogaster fasciatus. Curcumin produced time and concentration-dependent inhibition in the motility of treated metacercarial worms, with the maximum inhibition of motility reported at 60 μM along with a significant increase of (36–92%) in ROS and (57–112%) in GSH levels at the end of a period of 6 h. In contrast, curcumin at the highest concentration significantly inhibited the activities of the antioxidant and detoxification enzymes SOD (36%) and GST (16%), respectively, in addition to altering the polypeptide profile and inhibiting cysteine proteases. The tegumental surface appeared to be highly disrupted in curcumin-treated worms, exhibiting severe blebbing, shearing of the tegument, and spine erosion. Such changes would affect the tegumental functions and survival of worms in the hostile microenvironment. This would render worms more susceptible to host-mediated rejection responses. Based on the results of the present study, it is inferred that C. complanatum could serve as an excellent model for screening novel anthelmintic drugs against larval trematodes of great economic significance. Furthermore, we conclude that curcumin could be exploited as an excellent phytotherapeutic agent against the virulent larval form under investigation. [Display omitted] • The anthelmintic effects of curcumin is demonstrated on the infective progenetic metacercarial stage of C. complanatum. • Curcumin induces alterations in the levels of (ROS) and SOD activity, while increasing levels of GSH and (GST). • Curcumin causes changes in the polypeptide profile of the worm and inhibits its cysteine protease activity. • Curcumin severely disrupts the tegumental surface of the worm, contributing to its anthelmintic effects. [ABSTRACT FROM AUTHOR]

The helminth parasites possess great capabilities to adapt themselves within their hosts and also develop strategies to render the commonly used anthelmintics ineffective leading to the development of resistance against these drugs. Besides using anthelmintics the natural products have also been tested for their anti-parasitic effects. Therapeutic efficacy of honey bee venom (HBV) has been tested in various ailments including some protozoal infections but very little is known about its anthelmintic properties. To investigate the anthelmintic effect of HBV the excysted progenetic metacercariae of Clinostomum complanatum , a heamophagic, digenetic trematode with zoonotic potential, infecting a wide variety of hosts, were obtained from Trichogaster fasciatus, a forage fish, which serves as the intermediate host. The metacercarial worms were in vitro incubated in RPMI-1640 medium containing HBV along with the controls which were devoid of HBV for the analysis of worm motility, enzyme activity, polypeptide profile and surface topographical changes. The motility of the worms was significantly reduced in a time dependent manner with an increase in the concentration of HBV. Following incubation of worms the release of cysteine proteases was inhibited in the presence of HBV as revealed by gelatine substrate gel zymography. As well as the polypeptide profile was also significantly influenced, particularly intensity/expression of M r 19.4 kDa, 24 kDa and 34 kDa was significantly reduced upon HBV treatment. The HBV treatment also inhibited antioxidant enzyme, superoxide dismutase (SOD) and Glutathione-S-transferase (GST) significantly (p < 0.05) in the worms. The scanning electron microscopy of the HBV treated worms revealed tegumental disruptions and erosion of papillae as well as spines showing vacuolation in the tegument. The HBV treated worms also showed a marked decline in the transformation rate when introduced into an experimental host which further reflect the anthelmintic potential of HBV. [ABSTRACT FROM AUTHOR]

A S-scheme heterojunction of CuPc/DR-MoS 2 with abundant sulfur vacancies is proposed, enabling extended visible-light absorption, enhanced charge carrier separation/transfer, and improved efficiency of semiconductors. Additionally, sulfur vacancies play a significant role in enhancing CO 2 adsorption/activation on the photocatalyst surface during photocatalysis. [Display omitted] Constructing a heterojunction by combining two semiconductors with similar band structures is a successful approach to obtaining photocatalysts with high efficiency. Herein, a CuPc/DR-MoS 2 heterojunction involving copper phthalocyanine (CuPc) and molybdenum disulfide with S-rich vacancies (13.66%) is successfully prepared by the facile hydrothermal method. Experimental results and theoretical calculations firmly demonstrated that photoelectrons exhibit an S-scheme charge transfer mechanism in the CuPc/DR-MoS 2 heterojunction. The S-scheme heterojunction system has proven significant advantages in promoting the charge separation and transfer of photogenerated carriers, enhancing visible-light responsiveness, and achieving robust photoredox capability. As a result, the optimized 3CuPc/DR-MoS 2 S-scheme heterojunction exhibits photocatalytic yields of CO and CH 4 at 200 and 111.6 μmol g-1h−1, respectively. These values are four times and 4.5 times greater than the photocatalytic yields of pure DR-MoS 2. This study offers novel perspectives on the advancement of innovative and highly effective heterojunction photocatalysts. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterojunctions enhance photocatalyst efficiency but face electron transfer challenges at component interfaces due to large spacing and potential barriers. We introduce a novel wet chemistry approach to enhance the efficiency of photocatalysts by creating a functionalized graphene-modulated Z-scheme vdW heterojunction (xZnPc/yG-WO 3) to eliminate interfacial potential differences, enabling better electron transfer for improved photocatalytic reactions and molecular dispersion. [Display omitted] The construction of van der Waals (vdW) heterojunctions is a key approach for efficient and stable photocatalysts, attracting marvellous attention due to their capacity to enhance interfacial charge separation/transfer and offer reactive sites. However, when a vdW heterojunction is made through an ex-situ assembly, electron transmission faces notable obstacles at the components interface due to the substantial spacing and potential barrier. Herein, we present a novel strategy to address this challenge via wet chemistry by synthesizing a functionalized graphene-modulated Z-scheme vdW heterojunction of zinc phthalocyanine/tungsten trioxide (xZnPc/yG-WO 3). The functionalized G-modulation forms an electron "bridge" across the ZnPc/WO 3 interface to improve electron transfer, get rid of barriers, and ultimately facilitating the optimal transfer of excited photoelectrons from WO 3 to ZnPc. The Zn2+ in ZnPc picks up these excited photoelectrons, turning CO 2 into CO/CH 4 (42/22 μmol.g−1.h−1) to deliver 17-times better efficiency than pure WO 3. Therefore, the introduction of a molecular "bridge" as a means to establish an electron transfer conduit represents an innovative approach to fabricate efficient photocatalysts designed for the conversion of CO 2 into valued yields. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2D/2D Van der Waals (VDW) heterojunction between BCN/CuPc. • Phosphate group insertion between copper phthalocyanine (CuPc) and B-doped and N -deficient g-C 3 N 4 (BDCNN) to design and construct a Van der Waals heterojunction. • Phosphate group as a charge modulator and an efficient conduit for charge transfer. • Interfacial interaction charge transfer mechanism. The realization of 2D/2D Van der Waals (VDW) heterojunctions represents an advanced approach to achieving superior photocatalytic efficiency. However, electron transfer through Van der Waals heterojunctions formed via ex-situ assembly encounters significant challenges at the interface due to contrasting morphologies and potential barriers among the nanocomposite substituents. Herein, a novel approach is presented, involving the insertion of a phosphate group between copper phthalocyanine (CuPc) and B-doped and N -deficient g-C 3 N 4 (BDCNN), to design and construct a Van der Waals heterojunction labeled as xCu[acs]/yP-BDCNN. The introduction of phosphate as a charge modulator and efficient conduit for charge transfer within the heterojunction resulted in the elimination of spatial barriers and induced electron movement from BDCNN to CuPc in the excited states. Consequently, the catalytic central Cu2+ in CuPc captured the photoelectrons, leading to the conversion of CO 2 to C 2 H 4 , CO and CH 4. Remarkably, this approach resulted in a 78-fold enhancement in photocatalytic efficiency compared to pure BDCNN. Moreover the findings confirm that the 2D-2D 4Cu[acs]/9P-BDCNN sheet-like heterojunction effectively boosts photocatalytic activity for persistent pollutants such as methyl orange (MO), methylene blue (MB), rhodamine B (RhB), and tetracycline antibiotics (TCs). The introduction of "interfacial interacting" substances to establish an electron transfer pathway presents a novel and effective strategy for designing photocatalysts capable of efficiently reducing CO 2 into valuable products. [ABSTRACT FROM AUTHOR]

Fasciolosis is a neglected tropical disease caused by the liver fluke Fasciola gigantica. The absence of successful vaccine and emerging resistance in flukes against the drug of choice, triclabendazole, has necessitated the search for alternatives including phyto-therapeutic approaches. Curcumin and thymoquinone, the active ingredients of Curcuma longa and Nigella sativa plants respectively, were first screened for their binding affinity with Glutathione-S-transferase (GST) molecule through in silico molecular docking followed by in vitro treatment of worms with varying concentrations of the test compounds. The in silico molecular docking of curcumin and thymoquinone with sigma GST revealed strong hydrogen bonding as well as hydrophobic interactions with high fitness scores but showing inter-specific differences. The in vitro treatment of F. gigantica worms with both curcumin and thymoquinone resulted in a significant increase in the generation of reactive oxygen species (ROS) whereas the level of reduced glutathione, a primary redox regulator, was found to be significantly decreased (p < 0.05). The two compounds not only inhibited the GST activity, which is an important detoxification enzyme and also a key drug/vaccine target for the control of fasciolosis but also significantly inhibited the activity of antioxidant enzymes glutathione peroxidase and glutathione reductase that are vital in maintenance of redox homeostasis. The immunohistochemistry performed using anti sigma GST polyclonal antibodies revealed that both the compounds used in the present study significantly reduced immunofluorescence in the vitellaria, developing eggs present in the ovary and the intestinal caecae indicating inhibition of GST enzyme in these regions of the worms. Further, following treatment with curcumin and thymoquinone, chromatin condensation and DNA fragmentation was also observed in F. gigantica worms. In conclusion, both curcumin and thymoquinone generated oxidative stress in the worms by production of ROS and significantly inhibiting their antioxidant and detoxification ability. The oxidative stress along with induction of apoptotic like events would compromise the survival ability of worms within the host. However, further studies are required to establish their anthelmintic potential alone and in combination with the commonly used anthelmintic drugs under in vivo conditions. Image 1 • Curcumin and thymoquinone generate oxidative stress in adult F. gigantica flukes through increased production of ROS. • The treated worms showed decreased GSH, GST, GPX and GR activity. • DNA damage and chromatin condensation was also observed indicating towards apoptotic like events in the treated flukes. [ABSTRACT FROM AUTHOR]

The existence of heavy metals in ecological systems poses great threats to living organisms due to their toxicant and bio-accumulating properties. Mercury is a known toxicant with notable malignant impacts. It has long been known to cause toxic threats to the health of living organisms since the break out of Minamata disease. The turbulent expulsion of mercury-based pollutants from the industrial sector, requires a proper solution. Many attempts have been made to design a greener and more efficient route for a satisfactory removal of mercury. In the current study, bismuth sulfide nanoparticles (BiSNPs) have been synthesized via the co-precipitation method. The BiSNPs were supported with crosslinked chitosan to enhance their sorption capacity and avoid leaching. The average size of the BiSNPs was 42 nm based on SEM micrographs. The SEM analysis of the bismuth sulfide chitosan-crosslinked beads (BiS-CB) showed that the beads possessed a spherical and smooth morphology with a size of 1.02 mm. The FTIR analysis showed that the beads possessed the characteristics bands of imine groups of chitosan, bismuth, sulfur, and glycosidic linkages present in the molecules. The XRD analysis confirmed the phase crystallinity of the BiS-CB with an average crystallite size of 11 nm. The BiS-CB was employed for the sorption of mercury from water samples. The maximum sorption capacity of 65.51 mg/g was achieved at optimized conditions of pH 5, concentration 80 ppm, in 45 min at 30 °C. The mechanism studied for mercury removal showed that sorption followed the complexation mechanism according to the SHAB concept. In conclusion, the results showed that the BiS-CB sorbent exhibited an excellent sorption capacity to remove mercury. [Display omitted] [ABSTRACT FROM AUTHOR]