Fuzhuan brick tea is a dark tea produced using tea plant leaves, and its quality is strongly affected by Eurotium cristatum. The superior Eurotium cristatum strain could enhance functional components in Fuzhuan brick tea, improving its quality and economic value. To research the lipid-lowering substance of Eurotium cristatum in Fuzhuan brick tea from Anhua country tea production area, several wild-type Eurotium cristatum strains were screened for lovastatin production. Of all 20 wild-type strains, 6 Eurotium cristatum strains could produce lovastatin, and the H20 test strain could produce the highest lovastatin. The organ of lovastatin production was studied, and its yield in sexual propagule (ascospore and ascocarp) was the highest. Some fermentation parameters for lovastatin produced by the H20 strain were researched, and the optimum condition, such as PDA medium containing additional 8% soluble starch, 32 °C, and 120 r/min, are reported. These results are promising for developing one Fuzhuan brick tea with a high lipid-lowering function and expanding the scope of tea plant forest resource application.

The tea plant is a vital strategic forest resource in China. Dark tea produced from its leaves is an indispensable health-promoting product in western China due to its unique lipid-lowering function. Eurotium cristatum is the dominant strain in Fuzhuan brick tea (a variety of Anhua dark tea) and could produce many functional components, including lovastatin, a lipid-lowering compound. In this study, the lovastatin yield of dark tea was improved by breeding Eurotium cristatum using the protoplast fusion method. The experiments were carried out by inducing a fusion between inactivated Eurotium cristatum JH1205 and Monascus CICC5031. Among the 92 fusants screened the HPLC method, four strains (A4, A36, A54, and A76) with higher lovastatin production (more than three times as high) were obtained. The A76 strain had the highest lovastatin yield, which was 23.93 μg/mL. The location of the tea forest strongly influenced the lovastatin yield of loose dark tea. The strain bred in this study improved the lovastatin yield of loose dark tea by more than three times when compared to wild Eurotium cristatum. These results are promising for the development of tea forest resources.

Larch tannin, a valuable forest product resource, offers the benefits of being natural, renewable and environmentally friendly. With growing environmental concerns, the widespread use of phenolic resins in the wood industry has been limited due to the depletion of fossil resources and formaldehyde emission issues. In this study, larch tannin was modified using a NaOH/urea solution to enhance phenolic resin properties. The curing properties and thermal stability of the adhesives were analyzed using a differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA), and the formaldehyde emissions were also measured. The results showed that this treatment effectively reduced the resin’s gel time. LTPF-U-4 resin demonstrated the highest bonding strength of 1.09 MPa and exhibited low formaldehyde emissions, thereby meeting the requirements for Class I plywood (≥0.7 MPa) and complying with the E0 grade of plywood standards as outlined in the China National Standard GB GB/T 17657-2013. The sodium hydroxide/urea-treated larch tannin substitution improved the bonding performance of the LTPF-U resins; its impact on bonding strength is limited. Nevertheless, the treatment significantly reduces the formaldehyde emissions of plywood bonded with LTPF-U resins. The NaOH/urea treatment not only reduced the thermal stability of the resin but also improved its curing properties and lowered its curing temperature. This research offers valuable insights for developing modified phenolic resins, which have significant practical implications.

Broussonetia papyrifera is a deciduous tree with significant economic and medicinal value. It demonstrates notable physiological adaptability to mining areas with severe manganese contamination and is a pioneering species in the field of ecological restoration. Flavonoids are vital secondary metabolites that improve plant resilience to environmental stresses. In the study presented herein, immature and mature fruits of B. papyrifera grown in normal and high manganese environments were used as the test materials. B. papyrifera fruit was subjected to transcriptome sequencing via high-throughput sequencing technology to analyze its flavonoid metabolic pathways and related genes. Transcriptome sequencing identified a total of 46,072 unigenes, with an average length of 1248 bp and a percentage of Q30 bases ranging from 92.45 to 93.17%. Furthermore, 31,792 unigenes (69% of the total) were annotated using eight databases, including the GO and KEGG. Analysis of KEGG metabolic pathways and flavonoid content trends in B. papyrifera fruits revealed four unigenes with strong links to the flavonoid biosynthesis pathway under manganese stress: flavone 3-hydroxylase, flavonoids 3′,5′-O-methyltransferase, chalcone synthase, and flavonol synthase. These unigenes may play important roles in regulating flavonoid synthesis in B. papyrifera fruits under manganese stress. This study lays the groundwork for functional gene research in B. papyrifera.

Most wood-based panels were currently prepared using aldehyde-based adhesives, making the development of natural, renewable, and eco-friendly biomass-based adhesives a prominent area of research. Herein, the phenolic resin was modified using a soybean protein isolate (SPI) treated with a NaOH/urea solution through a copolymerization method. The physicochemical properties, chemical structure, bonding properties, and thermal properties of the soybean protein-modified phenolic resin (SPF-U) were analyzed using Fourier transform infrared spectroscopy, thermogravimetric analysis, and formaldehyde emission tests. The results indicated that the molecular structure of the soy protein isolate degraded after NaOH/urea solution treatment, while the gel time was gradually shortened with increasing NaOH/urea solution-treated soy protein isolate (SPI-U) dosages. Although the thermal stability of the soy protein isolate was lower than that of the phenolic resin, the 20% SPF-U resin demonstrated better thermal stability than other modified resins. The PF modified with 30% SPI-U (SPF-U-3) exhibited the lowest curing peak temperature of 139.69 °C than that of the control PF resin. In addition, all modified PF resins exhibited formaldehyde emissions ranging from 0.18 to 0.38 mg/L when the SPI-U dosage varied between 20% and 50%, thereby meeting the E0 plywood grade standard (≤0.5 mg/L).

Forest plants contain abundant natural products, providing a valuable resource for obtaining compounds with various functional activities, such as antimicrobial, lipid-lowering, and immunoregulatory activities. The development of efficient tools for rapidly screening functional natural products from forest plants is essential for human health. In this study, we constructed some transgenic strains (Escherichia coli) containing Ahy1-1 riboswitches that respond to cyclic di-guanylate (c-di-GMP), serving as a novel bacteriostatic target. The Ahy1-1 riboswitches contained the LacZ gene (encoding β-galactosidase) and c-di-GMP aptamer in order to monitor β-galactosidase activity due to changes in c-di-GMP. After co-incubating with extracts from fresh orange peel, fresh tea leaves, and Fuzhuan brick tea, the orange peel exhibited a significant inhibition of c-di-GMP generation. The extract of tea leaves had a minor influence on the synthesis of c-di-GMP, whereas Fuzhuan brick tea, which is fermented by various microorganisms, inhibited the production of c-di-GMP. Our constructed transgenic strains could be used to screen for antibacterial agents from forest plants. Beyond antibacterial agents, other functional compounds from forest plants could be selected by designing diverse riboswitches.