The occurrence of fluoroquinolone antibiotics in wastewater has drawn great attention. Adsorption of widely used fluoroquinolone antibiotics (enrofloxacin and ofloxacin) in wastewater using bamboo biochar was investigated. More than 99% of fluoroquinolone antibiotics were removed from the synthetic wastewater through adsorption. Adsorption capacities of bamboo biochar slightly changed when pH increased from 3.0 to 10.0. The adsorption capacity of bamboo biochar increased sharply when the initial concentration of enrofloxacin or ofloxacin increased from 1 to 200 mg L⁻¹ and then began to plateau with further increases in initial concentration. The maximum adsorption capacity (45.88 ± 0.90 mg·g⁻¹) was observed when the ratio of bamboo biochar to fluoroquinolone antibiotics was 10. The enrofloxacin adsorption capacity of bamboo biochar decreased from 19.91 ± 0.21 mg·g⁻¹ to 14.30 ± 0.51 mg·g⁻¹ while that of ofloxacin decreased from 19.82 ± 0.22 mg·g⁻¹ to 13.31 ± 0.56 mg·g⁻¹ when the NaCl concentrations increased from 0 to 30 g·L⁻¹. The adsorptions of fluoroquinolone on bamboo biochar have isotherms that obeyed the Freundlich model (r² values were in the range of 0.990–0.991).

Ionic liquids (ILs), known as environmentally benign “green” solvents, were developed as an optimal solvent for the green extraction and separation field. In this paper, an ionic liquid-based ultrasonic-assisted extraction (IL-UAE) of flavonoids (FVs) from bamboo leaves of Phyllostachys heterocycla was developed for the first time. First, 1-butyl-3-methylimidazolium bromide ([Bmim] Br), with the best extraction efficiency, was selected from fifteen ionic liquids with diverse structure, like carbon chains or anions. Then, the influencing parameters of ionic liquid (IL) concentration, liquid-solid ratio, ultrasonic time, and ultrasonic power, were investigated by single factor tests, and further optimized using response surface methodology (RSM). In the optimization experiment, the best conditions were 1.5 mol/L [BMIM]Br aqueous solution, liquid-solid ratio 41 mL/g, ultrasonic time 90 min, and ultrasonic power 300 W. Furthermore, the microstructures of bamboo leaves and the recovery of FVs and [BMIM]Br were also studied. Therefore, this simple, green and effective IL-UAE method has potentiality for the extraction of FVs from bamboo leaves for the large-scale operations.

Sea buckthorn is rich in polyphenolic compounds with antioxidant activities. However, it is very sour, and its odor is slightly unpleasant, so it requires flavor improvement. Fermentation is one potential method. Sea buckthorn juice was fermented at 37 °C for 72 h and then post-fermented at 4 °C for 10 days. The flavor-related properties of the sea buckthorn juice were evaluated during fermentation, including the pH, total soluble solids (TSS), color, sensory evaluation, and volatile flavors. The sea buckthorn fermented juice had a low pH. The total soluble solids decreased from 10.60 ± 0.10% to 5.60 ± 0.12%. The total color change was not more than 20%. Fermentation increased the sweet odor of the sea buckthorn juice, but the fruity flavor decreased and the bitter flavor increased. A total of 33 volatile flavors were identified by headspace gas chromatography–ion mobility spectrometry (GC–IMS), including 24 esters, 4 alcohols, 4 terpenes, and 1 ketone. Their total relative contents were 79.63–81.67%, 10.04–11.76%, 1.56–1.22%, and 0.25–0.55%, respectively. The differences in the characteristic volatile molecular species of the sea buckthorn juice at different fermentation stages could be visually discerned using fingerprint maps. Through principal component analysis (PCA), the total flavor difference of the sea buckthorn juice at different fermentation stages could be effectively distinguished into three groups: the samples fermented for 0 h and 12 h were in one group, the samples fermented for 36 h, 48 h, 60 h, and 72 h were in another group, and the samples fermented for 24 h were in another group. It is suggested that sea buckthorn juice be fermented for 36 h to improve its flavor. GC–IMS and PCA are effective methods of identifying and distinguishing the flavor characteristics of sea buckthorn juice. The above results can provide a theoretical basis for studying the changes in sea buckthorn’s characteristics as a result of fermentation, particularly with regard to its flavor.

Polysaccharides, which can be affected by different preparations, play a crucial role in the biological function of Paecilomyces hepiali (PHPS) as a health food. To explore high-valued polysaccharides and reduce the negative influence of human involvement, a green tailorable deep eutectic solvent (DES) was applied to optimize the extraction of polysaccharides (PHPS-D), followed by the evaluation of the structural properties and immunomodulation by comparison with the hot-water method (PHPS-W). The results indicated that the best system for PHPS-D was a type of carboxylic acid-based DES consisting of choline chloride and succinic acid in the molar ratio of 1:3, with a 30% water content. The optimal condition was as follows: liquid–solid ratio of 50 mL/g, extraction temperature of 85 °C, and extraction time of 1.7 h. The actual PHPS-D yield was 12.78 ± 0.17%, which was obviously higher than that of PHPS-W. The structural characteristics suggested that PHPS-D contained more uronic acid (22.34 ± 1.38%) and glucose (40.3 ± 0.5%), with a higher molecular weight (3.26 × 10⁵ g/mol) and longer radius of gyration (78.2 ± 3.6 nm), as well as extended chain conformation, compared with PHPS-W, and these results were confirmed by AFM and SEM. Immunomodulatory assays suggested that PHPS-D showed better performance than PHPS-W regarding pinocytic activity and the secretion of NO and pro-inflammatory cytokines (IL-6, TNF-α and IL-1β) by activating the corresponding mRNA expression in RAW264.7 cells. This study showed that carboxylic acid-based DES could be a promising tailorable green system for acidic polysaccharide preparation and the valorization of P. hepiali in functional foods.

In order to study the effect of both greenhouse and forest cultivating environments on Stropharia rugosoannulata, its volatile aroma compounds were measured by a headspace solid phase micro extractions—gas chromatograph—mass spectrometer (SPME–GC–MS). The optimal adsorption temperature was 75 °C and the optimal adsorption time was 40 min. A total of 36 volatile aroma compounds were identified by GC–MS, including 8 aldehydes, 2 ketones, 4 alcohols, 15 alkenes, and 4 alkanes. Hexanal, 3-Octanone, 2-Undecanone, (E)-Nerolidol, and (Z)-β-Farnesene made great aromatic contributions. Among them, Hexanal, 3-Octanone, 2-Undecanone were the key aroma compounds for which odor activity values (OAVs) were more than 1. (E)-Nerolidol showed odor modification in the forest samples and showed a key aroma effect in greenhouse samples. (Z)-β-Farnesene showed odor modification in greenhouse samples. 3-Octanone was the largest contributing compound for which the OAV was more than 60. The total content of volatile aroma compounds first increased and then decreased with growth time; it reached the highest level at 48 h: 2203.7 ± 115.2 μg/kg for the forest environment and 4516.6 ± 228.5 μg/kg for the greenhouse environment. The aroma was the most abundant at this time. All samples opened their umbrella at 84 h and become inedible. Principal component analysis (PCA), hierarchical cluster analysis (HCA), and orthogonal partial least squares discriminant analysis (OPLS–DA) were combined to analyze the aroma difference of S. rugosoannulata under two cultivation modes. PCA and HCA could effectively distinguish the aroma difference in different growth stages. Under different culturing methods, the aroma substances and their changes were different. The samples were divided into two groups for forest cultivation, while the samples were divided into three groups for greenhouse cultivation. At the end of growth, the aroma of S. rugosoannulata with the two cultivation modes was very similar. OPLS–DA clearly distinguished the differences between the two cultivation methods; 17 key aroma difference factors with variable importance projection (VIP) > 1 were obtained from SPLS–DA analysis.

When the total phenolic content (TPC) and antioxidant activity of sea buckthorn juice were assayed by spectrophotometry, the reaction solutions were not clarified, so centrifugation or membrane treatment was needed before determination. In order to find a suitable method for determining TPC and antioxidant activity, the effects of centrifugation and nylon membrane treatment on the determination of TPC and antioxidant activity in sea buckthorn juice were studied. TPC was determined by the Folin-Ciocalteau method, and antioxidant activity was determined by DPPH, ABTS, and FRAP assays. For Treatment Method (C): the sample was centrifuged for 10 min at 10,000 rpm and the supernatant was taken for analysis. Method (CF): The sample was centrifuged for 10 min at 4000 rpm, filtered by Nylon 66 filtration membranes with pore size of 0.22 μm, and taken for analysis. Method (F): the sample was filtered by Nylon 66 filtration membranes with pore size of 0.22 μm and taken for analysis. Method (N): after the sample of ultrasonic extract solution reacted completely with the assay system, the reaction solution was filtered by Nylon 66 filtration membranes with pore size of 0.22 μm and colorimetric determination was performed. The results showed that centrifugation or transmembrane treatment could affect the determination of TPC and antioxidant activity of sea buckthorn juice. There was no significant difference (p > 0.05) between methods (CF) and (F), while there was a significant difference (p < 0.05) between methods (C) (F) (N) or (C) (CF) (N). The TPC and antioxidant activity of sea buckthorn juice determined by the four treatment methods showed the same trend with fermentation time, and the TPC and antioxidant activity showed a significant positive correlation (p < 0.05). The highest TPC or antioxidant activity measured by method (N) indicates that method (N) has the least loss of TPC or antioxidant activity, and it is recommended for sample assays.