Photoinduced charge generation of nanostructured carbon derived from human hair biowaste for performance enhancement in polyvinylidene fluoride based triboelectric nanogenerator.

Carbon nanostructures derived from human hair biowaste are incorporated into polyvinylidene fluoride (PVDF) polymer to enhance the energy conversion performance of a triboelectric nanogenerator (TENG). The PVDF filled with activated carbon nanomaterial from human hair (AC-HH) exhibits improved surface charge density and photoinduced charge generation. These remarkable properties are attributed to the presence of graphene-like nanostructures in AC-HH, contributing to the augmented performance of PVDF@AC-HH TENG. The correlation of surface morphologies, surface charge potential, charge capacitance properties, and TENG electrical output of the PVDF composites at various AC-HH loading is studied and discussed. Applications of the PVDF@AC-HH TENG as a power source for micro/nanoelectronics and a movement sensor for detecting finger gestures are also demonstrated. The photoresponse property of the fabricated TENG is demonstrated and analyzed in-depth. The analysis indicates that the photoinduced charge carriers originate from the conductive reduced graphene oxide (rGO), contributing to the enhanced surface charge density of the PVDF composite film. This research introduces a novel approach to enhancing TENG performance through the utilization of carbon nanostructures derived from human biowaste. The findings of this work are crucial for the development of innovative energy-harvesting technology with multifunctionality, including power generation, motion detection, and photoresponse capabilities.

Engleromophilane, a new broad spectrum bioactive eremophilane-type sesquiterpene from Engleromyces sinensis fungus.

A new eremophilane sesquiterpene, named engleromophilane (1) together with known eremoxylarin E (2) and steroids (3-7) were isolated from the fungus Engleromyces sinensis culture. The structures were deduced by the analysis of spectroscopic and MS data, together with the comparison of calculated 13C NMR chemical shifts and Electronic Circular Dichroism (ECD) spectra. Compound 1 showed cytotoxic effects against Hela, PC-3, HT29 and A549 cell lines with IC50 in the ranges of 4.84-9.48 µg/mL. Compounds 1 and 2 exhibited substantial antimicrobial activity against E. coli, S. aureus, and B. subtilis. Moreover, compounds 1-3 showed α-glucosidase inhibitory activity, in which 2 displayed a strong inhibitory effect with an IC50 value of 0.13 ± 0.01 µg/mL. This work has given additional value to the E. sinensis fungus as a remarkable bioactive compound producer, together with the possibility of increasing cultivation to industrial scales.

Antiproliferative polyketides from fungus Xylaria cf. Longipes SWUF08-81 in different culture media.

Bioactive compounds from the wood-decay fungus Xylaria cf. longipes SWUF08-81, cultivated in three different culture media (GM, YM and PDB), were isolated. Their structures and stereochemistry were deduced from spectroscopic and MS data analysis, together with quantum chemical calculations of 13C NMR chemical shifts and electronic circular dichroism (ECD) spectra. Five undescribed polyketides including dibenzofuran (1), mellein (2), dihydroisocoumarin (15), and two pyrans (16, 17), together with twenty-three compounds were determined. Compounds 18 and 20 were significantly toxic against cancer cell lines (HCT116, HT29, MCF-7 and HeLa) based on the MTT assay. Quantification by HPLC showed that 18 was produced three-fold higher in the broth of PDB than YM. These studies showed that the production of different compounds were primarily dependent on nutrition sources and it has given a starting point for the growth optimization conditions for the scaling up of bioactive compounds production.

Tocotrienol monomers and dimers from the roots of Litchi chinensis with tyrosinase inhibition activity.

Four undescribed modified tocotrienols, including two monomers, litchinols A (1) and B (2), and two walsurol dimers, δ,δ-walsurol (3) and γ,δ-bi-O-walsurol (4), as well as seven known compounds (5-11) were isolated from the roots of Litchi chinensis. The structures of the undescribed compounds were elucidated based on analyses of spectroscopic data and ECD spectra. All tocotrienol derivatives (1-6) were evaluated for their tyrosinase inhibition activity. Only monomers 1-2 and 5-6 displayed potent inhibitory activity and greater than kojic acid. Kinetic analysis revealed that the representative compound 2 was uncompetitive inhibitor with the inhibition constant value of 5.70 µM.

Fly ash boosted electrocatalytic properties of PEDOT:PSS counter electrodes for the triiodide reduction in dye-sensitized solar cells.

Fly ash solid waste from a power plant was applied in a solar cell application for the first time. A doctor blade was used to coat FTO-glass with a composite film of mixed fly ash and PEDOT:PSS (FP). XRD, FTIR, SEM, EDX, and BET analyses were used to elucidate the crystal structure, morphology, and functional groups of fly ash in the current research. A significantly high efficiency solar cell was fabricated utilizing fly ash. CV, Tafel, and EIS analyses indicated a decrease in charge transfer resistance and an increased catalytic activity in the counter electrodes. The performance of DSSCs made from FP counter electrodes varied depending on the percentage of fly ash particles present. Fly ash mixed with PEDOT:PSS in a concentration ratio of 2:5 g/mL showed a high efficiency of 4.23%, which is comparable to Pt DSSC's (4.84%). Moreover, FP-2:5 presented a more highly efficient electrode than counter electrodes made from PEDOT:PSS mixed with MoO (3.08%) and CoO (3.65%). This suitability of this low-cost CE material for use in DSSCs has been established.

A rare isoflavone-quinone and a new flavanone from the roots of Dalbergia stipulacea Roxb.

Two previously undescribed compounds, namely dalpulapans F and G (1 and 2), along with 11 known compounds were isolated from the MeOH crude extract of the roots of Dalbergia stipulacea. Dalpulapan F was found as a rare isoflavone-quinone derivative. Their structures and absolute configurations were supported by extensive spectroscopic data analysis, including 1 D and 2 D NMR, HRESIMS data, specific rotation data, and comparison of the experimental and calculated ECD data. Cytotoxicity evaluation of the isolated compounds against HepG2 and KKU-M156 cell lines revealed that isoflavonoid 9 and rotenoid 13 exhibited the most activity against the two cell lines.

Engineering Triboelectric Charge in Natural Rubber-Ag Nanocomposite for Enhancing Electrical Output of a Triboelectric Nanogenerator.

An environmentally friendly triboelectric nanogenerator (TENG) is fabricated from a natural rubber (NR)-Ag nanocomposite for harvesting mechanical energy from human motions. Ag nanoparticles (AgNPs) synthesized with two different capping agents are added to NR polymer for improving dielectric constant that contributes to the enhancement of TENG performance. Dielectric constant is modulated via interfacial polarization between AgNPs and NR matrix. The effects of AgNP concentration, particle size and dispersion in NR composite, and type of capping agents on dielectric properties and electrical output of the NR composite TENG are elucidated. It is found that, apart from AgNPs content in the NR-Ag nanocomposite, cations of CTAB capping agent play important roles not only on the dispersion of AgNPs in NR matrix but also on intensifying tribopositive charges in the NR composite. In addition, the application of the NR-Ag TENG as a shoe insole is also demonstrated to convert human footsteps into electricity to power small electronic devices. Furthermore, with the presence of Ag nanoparticles, the fabricated shoe insole also exhibits antibacterial property against Staphylococcus aureus that causes foot odor.

Eco-Friendly Triboelectric Material Based on Natural Rubber and Activated Carbon from Human Hair.

The triboelectric nanogenerator (TENG) has emerged as a novel energy technology that converts mechanical energy from surrounding environments to electricity. The TENG fabricated from environmentally friendly materials would encourage the development of next-generation energy technologies that are green and sustainable. In the present work, a green triboelectric material has been fabricated from natural rubber (NR) filled with activated carbon (AC) derived from human hair. It is found that the TENG fabricated from an NR-AC composite as a tribopositive material and a poly-tetrafluoroethylene (PTFE) sheet as a tribonegative one generates the highest peak-to-peak output voltage of 89.6 V, highest peak-to-peak output current of 6.9 µA, and can deliver the maximum power density of 242 mW/m2. The finding of this work presents a potential solution for the development of a green and sustainable energy source.

New iridoid glucosides from the roots of Rothmannia wittii (Craib) Bremek.

Phytochemical investigation of the roots of Rothmannia wittii led to the isolation of three new iridoid glucosides, named rothmanniosides A-C (1-3), and nine known compounds (4-12). Their structures, including their absolute configurations, were elucidated by thorough analysis of mass spectrometric and NMR spectroscopic data, together with CD calculations. Compounds 4 and 11 are reported from the Rubiaceae family for the first time.

Brandisianones F and G from Millettia brandisiana Kurz and their cytotoxicity.

A new flavanone and a new chalcone, brandisianones F and G, were purified from the roots of Millettia brandisiana Kurz, moreover, sixteen known compounds were found. The chemical structures of all isolated compounds were identified using spectroscopic methods including 1D-NMR, 2D-NMR, MS, IR and CD data. Chalcone 15 exhibited the most cytotoxic activity against liver cancer, HepG2, and cholangiocarcinoma, KKU-M156, cell lines with IC50 values of 1.74 ± 0.91 and 1.95 ± 0.95 µg/mL, respectively. Chalcones 2, 14, 16 and 18 as well as flavones 5, 6 and 12 showed moderate cytotoxicity with IC50 values ranging from 5.39 to 14.00 µg/mL.[Formula: see text].

Scalarane Sesterterpenoids with Antibacterial and Anti-Proliferative Activities from the Mushroom Neonothopanus nambi.

Seven undescribed scalarane sesterterpenoids, nambiscalaranes B-H (1-7), together with two known compounds, nambiscalarane (8) and aurisin A (9) were isolated from the cultured mycelium of the luminescent mushroom Neonothopanus nambi. Their structures were elucidated by thorough analysis of their 1D and 2D NMR spectroscopic data. The absolute configurations of 1-8 were determined by electronic circular dichroism (ECD) calculations and optical rotation measurements. The isolated sesterterpenoids were evaluated against A549, HT29, HeLa, and HCT-116 cancer cell lines, and against five bacterial strains. Compounds 3, 5, and 7 showed strong cytotoxicity against HCT-116 cell line, with IC50 values ranging from 13.41 to 16.53 µM, and showed no cytotoxicity towards Vero cells. Moreover, compound 8 inhibited the growth of Bacillus subtilis with a MIC value of 8 µg/mL, which was equivalent to the MIC value of the standard kanamycin.

Ag Nanoparticle-Incorporated Natural Rubber for Mechanical Energy Harvesting Application.

The energy conversion performance of the triboelectric nanogenerator (TENG) is a function of triboelectric charges which depend on the intrinsic properties of materials to hold charges or the dielectric properties of triboelectric materials. In this work, Ag nanoparticles were synthesized and used to incorporate into natural rubber (NR) in order to enhance the dielectric constant for enhancing the electrical output of TENG. It was found that the size of Ag nanoparticles was reduced with the increasing CTAB concentration. Furthermore, the CTAB surfactant helped the dispersion of metallic Ag nanoparticles in the NR-insulating matrix, which promoted interfacial polarization that affected the dielectric properties of the NR composite. Ag nanoparticle-incorporated NR films exhibited an improved dielectric constant of up to almost 40% and an enhanced TENG performance that generated the highest power density of 262.4 mW/m2.

Dalpulapans A-E from the roots of Dalbergia stipulacea.

Five new compounds, dalpulapans A-E (1-5), were isolated from the hexane extract of the roots of Dalbergia stipulacea Roxb. Five new compounds, dalpulapans A-E (1-5), were isolated from the hexane extract of the roots of Dalbergia stipulacea Roxb. An evaluation of cytotoxic activity against HeLa, A549 and normal cell lines using MTT assay was performed. The results showed that R,R-velucarpin A (6) was the most active against HeLa cells with an IC50 value of 10.9 ± 0.42 µM, while fortunately this compound exhibited weak cytotoxicity against normal cells (29.20 ± 1.16 µM). Structures of all isolates were identified from their 1D and 2D NMR spectroscopic data and MS analysis. Experimental and calculated ECD spectra were studied to define the absolute configurations.

Knecorticosanones C-H from the fruits of Knema globularia (Lam.) warb.

Six undescribed polyketides, 1-6, were discovered from the fruits of Knema globularia (Lam.) warb. Two known polyketides and three known lignans were also isolated. Cytotoxicities against HepG2 and KKU-M156 cells of all polyketides were evaluated. Compound 1 displayed the most cytotoxic activity against HepG2 and KKU-M156 cell lines with IC50 values of 1.57 ± 0.37 and 1.78 ± 0.14 µg mL-1, respectively. The structure of all isolates was identified using spectroscopic methods including NMR, IR, MS and ECD.

The quantum confined Stark effect in N-doped ZnO/ZnO/N-doped ZnO nanostructures for infrared and terahertz applications.

The terahertz (THz) frequency range is very important in various practical applications, such as terahertz imaging, chemical sensing, biological sensing, high-speed telecommunications, security, and medical applications. Based on the density functional theory (DFT), this work presents electronic and optical properties of N-doped ZnO/ZnO/N-doped ZnO quantum well and quantum wire nanostructures. The density of states (DOS), the band structures, effective masses, and the band offsets of ZnO and N-doped ZnO were calculated as the input parameters for the subsequent modeling of the ZnO/N-doped ZnO heterojunctions. The results show that the energy gaps of the component materials are different, and the conduction and valence band offsets at the ZnO/N-doped ZnO heterojunction give type-II alignment. Furthermore, the optical characteristics of N-doped ZnO/ZnO/N-doped ZnO quantum well were studied by calculating the absorption coefficient from transitions between the confined states in the conduction band under the applied electric field (Stark effect). The results indicate that N-doped ZnO/ZnO/N-doped ZnO quantum wells, quantum wires, and quantum cascade structures could offer the absorption spectrum tunable in the THz range by varying the electric field and the quantum system size. Therefore, our work indicates the possibility of using ZnO as a promising candidate for infrared and terahertz applications.

Diamond-Like Carbon Thin Film Electrodes for Microfluidic Bioelectrochemical Sensing Platforms.

This work aims to utilize diamond-like carbon (DLC) thin films for bioreceptor immobilization and amperometric biosensing in a microfluidic platform. A specific RF-PECVD method was employed to prepare DLC thin film electrodes with desirable surface and bulk properties. The films possessed a relatively high sp2 fraction, a moderate electrical conductivity (7.75 × 10-3 S cm-1), and an optical band gap of 1.67 eV. X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy revealed a presence of oxygen-containing functional groups on the DLC surface. The DLC electrodes were integrated into polydimethylsiloxane (PDMS) microfluidic electrochemical cells with the channel volume of 2.24 µL. Glucose oxidase (GOx) was chosen as a model bioreceptor to validate the employment of DLC electrodes for bioelectrochemical sensing. In-channel immobilization of glucose oxidase (GOx) at the DLC surface was realized through carbodiimide covalent linkages. Enzyme bound DLC electrode was confirmed with the redox potential at around -79 mV vs NHE in 0.1 M phosphate buffer pH 7.4. Amperometric flow-injection glucose sensing at a potential of -0.45 V vs Ag in the absence of standard redox mediators showed the increase of current response upon increasing the glucose concentration. The sensing mechanism is based on the reduction process of H2O2 liberated from the enzymatic activity. The proposed model for the catalytic H2O2 reduction to H2O on DLC electrodes was attributed to the dissociation of C-O bonds at the DLC surface.

Styrenes from the Seeds of Atalantia monophylla.

Four new dimeric styrenes, 1-4, were isolated from an EtOAc crude extract of the seeds of Atalantia monophylla. The biosynthetic pathway of 1 is proposed to involve a [2 + 2] cycloaddition, while 2-4 may be generated via a polar mechanism with a carbocation as the key intermediate. The structures of 1-4 were defined from spectroscopic analysis; experimental and calculated ECD spectra were used to characterize their absolute configurations. When tested against two different cancer cell lines, 1-4 were not determined to be cytotoxic (IC50 > 10 µM).

Types A and D Trichothecene Mycotoxins from the Fungus Myrothecium roridum.

Chromatographic separation of extracts from the fungal biomass of a plant pathogenic fungus, Myrothecium roridum, yielded 8 trichothecene toxins including 6 type D trichothecenes (1: -6: ) and 2 type A trichothecenes (7: -8: ). 6',12'-Epoxymyrotoxin A (1: ) and 7'-hydroxymytoxin B (2: ) were new macrocyclic trichothecenes, while the other trichothecenes were identified as myrotoxin B (3: ), myrotoxin D hydrate (4: ), 2',3'-epoxymyrothecine A (5: ), miotoxin A (6: ), and 2 trichothecenes lacking the macrocyclic lactone system, roridin L-2 (7: ) and trichoverritone (8: ). The structures of these mycotoxins were characterized using spectroscopic methods. The absolute configurations of 1: and 2: were determined by NOESY and a comparison of their experimental and calculated ECD spectra. Most of these mycotoxins (1: -4: and 6: ) exhibited highly potent antimalarial activity against Plasmodium falciparum. They also showed strong cytotoxicity towards KB and NCI-H187 cell lines (IC50 0.60 - 112.28 nM), as well as the Vero cell line (IC50 1.50 - 46.51 nM).

Hierarchical Fe3O4-reduced graphene oxide nanocomposite grown on NaCl crystals for triiodide reduction in dye-sensitized solar cells.

Cost-effective reduced graphene oxide sheets decorated with magnetite (Fe3O4) nanoparticles (Fe3O4-rGO) are successfully fabricated via a chemical vapor deposition (CVD) technique using iron (III) nitrate as an iron precursor, with glucose and CH4 as carbon sources, and NaCl as a supporting material. TEM analysis and Raman spectroscopy reveal hierarchical nanostructures of reduced graphene oxide (rGO) decorated with Fe3O4 nanoparticles. Fe K-edge x-ray absorption near edge structure (XANES) spectra confirm that the nanoparticles are Fe3O4 with a slight shift of the pre-edge peak position toward higher energy suggesting that the fabricated Fe3O4 nanoparticles have a higher average oxidation state than that of a standard Fe3O4 compound. The hierarchical Fe3O4-rGO is found to exhibit an excellent catalytic activity toward the reduction of triiodide to iodide in a dye-sensitized solar cell (DSSC) and can deliver a solar cell efficiency of 6.65%, which is superior to a Pt-based DSSC (6.37%).

Bioactive homogentisic acid derivatives from fruits and flowers of Miliusa velutina.

Chromatographic separation of fruits and flowers of the Thai medicinal plant, Miliusa velutina, resulted in the isolation of five new rare homogentisic acid derivatives, miliusanal (1) and miliusanones A-D (2-5), together with fifteen known secondary metabolites (6-20). Their structures were determined through the use of extensive spectroscopic data. The absolute configurations of homogentisic acid derivatives 2-7 were identified using NOESY data and a comparison of experimental and calculated ECD spectral data. Compounds 2, 3, 6, and 7 showed antimalarial activity with IC50 values in the range of 3.3-5.2 µg/mL. Compound 6 also showed activity against Mycobacterium tuberculosis with an MIC value of 50 µg/mL. Compounds 1-3, 6 and 7 exhibited cytotoxicity againt KB, MCF-7, NCI-H187 and Vero cell lines with IC50 values in the range of 5.8-40.4 µg/mL. In addition, compounds 1, 2 and 6 showed moderate antibacterial activities against three Gram-positive bacteria (Bacillus cereus, Staphylococcus aureus, and Methicillin resistant S. aureus) with MICs in the range of 32-64 µg/mL.