Composition of Organic Carbon-Based Compounds in the Stem Wood of Quercus mongolica Seedlings Grown Under Elevated CO2 and/or O3 Concentrations

In this study, we examined the composition of organic constituents of stem woody tissue together with tree growth in Quercus mongolica var. grosseserrata Blume seedlings raised under controlled CO2 and/or O3 concentrations in a Free-Air Concentration Enrichment system. After exposure to ambient air (control), elevated CO2 concentration (550 μmol mol–1 CO2), elevated O3 concentration (double that of the control), and a combination of elevated CO2 and O3 concentrations during a growing season, we measured the diameter and length of stem, and biomass of sampled seedlings and quantified the lignin, extractive, and holocellulose contents of the woody tissue of current-year stems. We confirmed that the growth of seedlings was enhanced under an elevated CO2 concentration condition. In line with this, the extractive content was lower in woody tissue formed under an elevated CO2 concentration than that formed under ambient air, whereas holocellulose content showed an inverse pattern. Elevated O3 concentration itself did not change the organic constituents of the woody tissue, but it reduced the influence of an elevated CO2 concentration. We thus assume that Q. mongolica formed woody tissue with a low extractive content under the high CO2 concentration condition, although this response was possibly mitigated by an elevated O3 concentration. Extractives contains antimicrobial components such as tannins, flavonoids, quinones, and terpenoids. The decrease in extractives within the widely distributed Q. mongolica in East Asia may have a non-negligible impact on C cycling in the future earth with high atmospheric CO2 concentration.

Penyarian Konstituen Organik Daging Buah Gaharu (Aquilaria malaccensis Lamk.) dengan Metode Maserasi Berbantu Microwave dan Uji Aktivitas Sebagai Antioksidan

This study was conducted to determine the organic constituents and to test the antioxidant activity and toxicity of gaharu fruit pulp extract (Aquilaria malaccensis Lamk.). Gaharu fruit pulp extract was obtained through Microwave Assisted Extraction (MAE) method and then extracted with a solvent with different polarity, namely ethyl acetate and n-hexane. The obtained yield of ethyl acetate extract of the gaharu fruit pulp was 40.827% w/v, whereas 0% w/v in n-hexane extract, therefore, no further test for n-hexane extract, so that the n-hexane extract was not tested for the next stage. The results of the organic constituents of the ethyl acetate extract of gaharu fruit pulp showed flavonoids, saponins, glycosides, phenols and tannins. Antioxidant activity testing was carried out using the DPPH method with vitamin C as a positive control. The results of the antioxidant activity test showed that IC50 of ethyl acetate extract of gaharu fruit pulp and vitamin C were 143.789ppm and 13.797ppm, respectively. Extracts from microwave-assisted maceration that were partitioned with ethyl acetate solvent were categorized into moderate antioxidants because the IC50 value was between 101-150ppm, while vitamin C was categorized as a strong antioxidant because the IC50 value was between 0-100ppm. Toxicity testing was also carried out on ethyl acetate extract of gaharu fruit pulp using the BSLT method. The results of the toxicity test of the ethyl acetate extract of gaharu fruit pulp showed activity with an LC50 value of 11.282ppm. Based on this research, the ethyl acetate extract of gaharu fruit pulp is considered to have an anticancer potential.

Wastewater Refinery: Producing Multiple Valuable Outputs from Wastewater

A wastewater refinery is a multifunctional solution that combines different technologies and processing schemes to recover a spectrum of valuable materials from municipal or industrial wastewater. The concept of wastewater refinery introduces a new perspective on wastewater treatment and management. It aims at making the most of wastewater constituents by co-producing different worthful outputs, such as water, energy, nitrogen, sulfide, and phosphorous. This can turn the treatment of wastewater from a major cost into a source of profit. The wastewater refinery approach is well aligned with the concept of the circular economy. A case study on Qatar’s wastewater revealed the potential recovery of significant quantities of valuable resources embodied in the country’s wastewater. Valorization of organic constituents and the recovery of nitrogen, phosphorus, and sulfide should be given priority. To facilitate the adoption of the wastewater refinery concept, research is required to explore technical and economic bottlenecks.