Enhanced extraction of bioactive compounds from propolis (Apis mellifera L.) using subcritical water.

The bioactive compounds and antioxidant activities of propolis extracts were investigated using subcritical water extraction (SWE). SWE was performed by varying temperature (110-200 °C) and time (10-30 min). SWE using only water as solvent successfully to extracted bioactive compounds from propolis using high-purity glass thimbles. The concentrations of galangin (16.37 ± 0.61 mg/g), and chrysin (7.66 ± 0.64 mg/g) were maximal at 200 °C for 20 min, and 170 °C for 20 min, respectively. The antioxidative properties from propolis increased with the increasing extraction temperature and extraction time on SWE. The maximum yields of the total phenolics (226.37 ± 4.37 mg/g), flavonoids (70.28 ± 1.33 mg/g), and antioxidant activities (88.73 ± 0.58%, 98.86 ± 0.69%, and 858.89 ± 11.48 mg/g) were obtained at 200 °C for 20 min. Compared with using ethanol extraction (at 25 °C for 24 h, total phenolics = 176.28 ± 0.35, flavonoids = 56.41 ± 0.65, antioxidant activities = 72.74 ± 0.41%, 95.18 ± 0.11%, 619.51 ± 8.17 mg/g), all yields of SWE extracts obtained at 200 °C for 20 min were higher. SWE is suitable for a much faster and more efficient method extracting bioactive compounds from propolis compared to traditional extraction method.

Rice straw-derived lipid production by HMF/furfural-tolerant oleaginous yeast generated by adaptive laboratory evolution.

Research on producing medium- and long-chain hydrocarbons as drop-in biofuels has recently accelerated. In addition, lipids are emerging as precursors for biofuel production, and thus, microbial lipid production utilizing agrowastes is becoming a feasible platform technology. Nonetheless, microorganisms are often inhibited by furan aldehydes in biomass-derived hydrolysates. Accordingly, this study aimed to develop oleaginous yeast strains that can tolerate furan aldehydes for producing lipids as biofuel precursors. Rhodosporidium toruloides was selected as the target for adaptive laboratory evolution. The evolved strain, which was obtained from 16 rounds of subcultures, showed a 2.5-fold higher specific growth rate than the wild-type strain in the presence of furan aldehydes and slightly higher lipid production in rice straw hydrolysate. The results discussed in this study provide insights into the production of lipid production by oleaginous yeast utilizing agrowastes as feedstock to obtain drop-in biofuels and contribute to feasible strategies to address climate crises.

Synthesis and Functionalization of Porous Zr-Diaminostilbenedicarboxylate Metal-Organic Framework for Storage and Stable Delivery of Ibuprofen.

A stable porous metal-organic framework (MOF), Zr-diaminostilbenedicarboxylate (Zr-DASDCA), was synthesized and modified with oxalyl chloride (OC) or terephthaloyl chloride (TC) to introduce various functional groups onto the Zr-DASDCA. Both pristine and functionalized Zr-DASDCAs, together with activated carbon, were used as a potential carrier for ibuprofen (IBU) storage and delivery. Zr-DASDCAs, especially the modified ones (OC-Zr-DASDCA and TC-Zr-DASDCA), showed competitive results in IBU delivery. Specifically, the release rate in phosphate-buffered saline solution at pH 7.4 was nearly constant (R 2 ≈ 0.98) for up to 10 days, which would be very effective in IBU dosing to the human body. Moreover, the release rate could be controlled by changing the pH of the releasing solution. The rate of IBU release from both pristine and modified Zr-DASDCAs at pH 7.4 and 3.0 was also explained with a few interactions such as H-bonding and electrostatic repulsion, together with the relative pore size of the Zr-DASDCAs. Therefore, the results suggested that functionalization of MOFs via postsynthetic modification, especially with OC and TC, to introduce various functional groups onto MOFs is an effective approach to not only reducing the release rate of IBU but also inducing a constant release of IBU for as long as 10 days.

Adsorptive removal of nitroimidazole antibiotics from water using porous carbons derived from melamine-loaded MAF-6.

Nitrogen-containing carbons were obtained via pyrolysis of melamine-loaded metal azolate frameworks (named mela@MAF-6), a sub-class of metal organic frameworks. The porosity and defect concentration of the obtained carbons (named as CDM@M-6) were dependent on the quantity of melamine loaded in the mela@MAF-6. The CDM@M-6 s were applied for the adsorptive removal of nitroimidazole antibiotics (NIABs) from water; the performance of CDM@M-6, particularly CDM(0.25)@M-6, was outstanding for the elimination of NIABs such as dimetridazole (DMZ), metronidazole (MNZ), and menidazole (MZ)) from water. The adsorption capacity of CDM(0.25)@M-6 for DMZ, MNZ, and MZ was higher than that of any adsorbent reported so far. The highest adsorptive performance of CDM(0.25)@M-6 for DMZ (Q0: 621 mg/g) and MNZ (Q0: 702 mg/g) was explained by hydrogen bonding, where CDM@M-6 and DMZ/MNZ acted as a H-donor and H-acceptor, respectively. In addition, CDM(0.25)@M-6 could be regenerated via ethanol washing and reused for next cycles without any severe decrease in performance. Therefore, CDM@M-6 is recommended as a suitable adsorbent for the elimination of NIABs from water.