(E)-2-(4-Chloro­benzyl­idene)indan-1-one

In the title compound, C16H11ClO, the dihedral angle between the almost planar dihydro­indene ring system (r.m.s. deviation = 0.009 Å) and the chloro­benzene ring is 3.51 (14)°. In the crystal, mol­ecules are connected by C—H⋯O and weak C—H⋯Cl inter­actions, forming infinite layers parallel to (101)

Correlation between the extraction yield of mangiferin to the antioxidant activity, total phenolic and total flavonoid content of Phaleria macrocarpa fruits

This paper elucidates the correlation between the yield of mangiferin extraction from Phaleria macrocarpa fruits to the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (AA). Mangiferin extraction was performed using an ultrasonic assisted extraction (UAE) method. The effect of particle size, solvent to solid ratio, solvent type, ethanol concentration, sonication amplitude and extraction time were studied. The best UAE condition was found using a particle size of 125–250 μm, solvent to solid ratio of 40 mL/g, 40% ethanol, sonication amplitude of 60% and extraction time of 5 min, which produced 28.6 mg mangiferin/g DW, 78.7 mg GA/g DW, 263.2 mg QE/g DW and 57.2% DPPH-RSA. The regression analysis showed a significant (p < 0.05) correlation between the mangiferin yield and either TPC, TFC or AA. The finding reported in this work provides a useful method to predict the mangiferin yield based on TPC, TFC or AA, without needing the actual external standard

POCER 1927: Microencapsulation by Spray Drying Enhanced Powder Recovery and Mangiferin Stability of Phaleria macrocarpa’s Extracts

A microencapsulation via spray-drying was evaluated for encapsulation of mangiferin extracted from Phaleria macrocarpa. The microencapsulation was performed using maltodextrin, whey protein isolate and a mixture of these components in a ratio of 9:1. The mangiferin was quantified using an ultra performance liquid chromatography coupled to the tunable UV detector and quadrupole time of flight mass spectrometer (UPLC TUV QTOF MS) and high performance liquid chromatography with diode array UV detector. It was found that encapsulation with maltodextrin yielded the lowest moisture content (7.3%) and yielded the highest powder yield (38.6%)

Functionalized Graphene-Incorporated Cupric Oxide Charge-Transport Layer for Enhanced Photoelectrochemical Performance and Hydrogen Evolution

The production of hydrogen (H2) through photoelectrochemical water splitting (PEC-WS) using renewable energy sources, particularly solar light, has been considered a promising solution for global energy and environmental challenges. In the field of hydrogen-scarce regions, metal oxide semiconductors have been extensively researched as photocathodes. For UV-visible light-driven PEC-WS, cupric oxide (CuO) has emerged as a suitable photocathode. However, the stability of the photocathode (CuO) against photo-corrosion is crucial in developing CuO-based PEC cells. This study reports a stable and effective CuO and graphene-incorporated (Gra-COOH) CuO nanocomposite photocathode through a sol-gel solution-based technique via spin coating. Incorporating graphene into the CuO nanocomposite photocathode resulted in higher stability and an increase in photocurrent compared to bare CuO photocathode electrodes. Compared to cuprous oxide (Cu2O), the CuO photocathode was more identical and thermally stable during PEC-WS due to its high oxidation number. Additionally, the CuO:Gra-COOH nanocomposite photocathode exhibited a H2 evolution of approximately 9.3 µmol, indicating its potential as a stable and effective photocathode for PEC-WS. The enhanced electrical properties of the CuO:Gra-COOH nanocomposite exemplify its potential for use as a charge-transport layer

Facile Synthesis of Colloidal CuO Nanocrystals for Light-Harvesting Applications

CuO is an earth-abundant, nontoxic, and low band-gap material; hence it is an attractive candidate for application in solar cells. In this paper, a synthesis of CuO nanocrystals by a facile alcohothermal route is reported. The nanocrystals are dispersible in a solvent mixture of methanol and chloroform, thus enabling the processing of CuO by solution. A bilayer solar cell comprising of CuO nanocrystals and phenyl-C61-butyric acid methyl ester (PCBM) achieved a power conversion efficiency of 0.04%, indicating the potential of this material for light-harvesting applications

Effect of extraction temperature and time on the extraction of phenolic compounds and antioxidant capacity of Phaleria macrocarpa fruit

Phaleria macrocarpa (ver. name:‘mahkota dewa’) is a plant which has many medically useful antioxidant activities (Anggraini & Lewandowsky, 2015). The polyphenols responsible for this antioxidant activity has to be extracted before it can be routinely used (Shwter et al., 2016). This study investigates the extraction of polyphenols from P. macrocarpa fruits and its antioxidant activity (DPPH-RSA) under influence of extraction time and temperature. By employing maceration technique, the P. macrocarpa fruits extract showed the maximum total phenolic content (TPC), total flavonoid content (TFC) and DPPH-RSA with value of 69.5 mg QE/g DW, 183.2 mg GA/g DW and 171. 8 mg BHA/g DW, respectively at optimum extraction conditions of 60 min and 80 ºC (Fig. 1). Excellent and positive Pearson correlation coefficient with R 2> 0.91 between the TPC, TFC and antioxidant activities was observed

Extrapolative Bayesian optimization with Gaussian process and neural network ensemble surrogate models

Bayesian optimization (BO) has emerged as the algorithm of choice for guiding the selection of experimental parameters in automated active learning driven high throughput experiments in materials science and chemistry. Previous studies suggest that optimization performance of the typical surrogate model in the BO algorithm, Gaussian processes (GPs), may be limited due to its inability to handle complex datasets. Herein, various surrogate models for BO, including GPs and neural network ensembles (NNEs), are investigated. Two materials datasets of different complexity with different properties are used, to compare the performance of GP and NNE—the first is the compressive strength of concrete (8 inputs and 1 target), and the second is a simulated high-dimensional dataset of thermoelectric properties of inorganic materials (22 inputs and 1 target). While NNEs can converge faster toward optimum values, GPs with optimized kernels are able to ultimately achieve the best evaluated values after 100 iterations, even for the most complex dataset. This surprising result is contrary to expectations. It is believed that these findings shed new light on the understanding of surrogate models for BO, and can help accelerate the inverse design of new materials with better structural and functional performance.Agency for Science, Technology and Research (A*STAR)Published versionThis work was supported by the Agency of Science, Technology and Research (A*STAR), Singapore, via two programmatic research grants (grant nos. A1898b0043 and A19E9a0103)

Correlation between the antioxidant, total flavonoid and total phenolic content of phaleria macrocarpa fruit extract

The effect of temperature and extraction time on the yield of polyphenol and antioxidant activity (DPPH-RSA) of Phaleria macrocarpa fruits was studied. The extraction of polyphenols from Phaleria macrocarpa fruit was performed using a maceration technique. The (TFC) Total Flavonoid Content and Total Phenolic Content (TPC) in the sample was analysed using aluminium chloride colorimetric assay and Singleton’s method, respectively. Meanwhile, the antioxidant activity was determined via DPPH assay. The optimum extraction condition was achieved at 80 ºC and 60 min which yielded 69.5 mg QE/g DW, 183.2 mg GA/g DW and 171.8 mg BHA/g DW, respectively. Pearson correlation coefficient analysis shows excellent correlation coefficient with R2 > 0.91 between the TPC, TFC and antioxidant activities. The method outlined here may serve as a guide to optimize the polyphenol extraction from Phaleria macrocarpa frui