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An endophytic fungus, Phoma sp. NG-25, produces a set of structurally related polyketides including cercosporamide, phomodione, and usnic acid, among which, cercosporamide has been reported to have strong antifungal and anticancer activities. In this study, Phoma sp. NG-25 was grown in seven growth media to determine the optimal culture condition conducive for cercosporamide production. Cercosporamide production peaked on the eighteenth day of incubation in beef peptone dextrose (BPD) broth media. The cercosporamide titer reached to an average of 77.5 µg/mL in BPD. Paper disk diffusion assay revealed that culture filtrate containing cercosporamide as a major constituent inhibited the growth of taxonomically diverse plant pathogens, including ascomycetous, basidiomycetous, and oomycete fungi. Cercosporamide exhibited strong antifungal activities against two pepper anthracnose pathogens, Colletotrichum gloeosporioides and C. scovillei with EC50 values of 3.8 and 7.0 µg/mL, respectively. This study suggests the potential application of cercosporamide as an effective antifungal agent in controlling anthracnose in pepper. [ABSTRACT FROM AUTHOR]

Preparing 2-methoxy-4-methylphenol (MMP) through the vanillin (VAN) route is a crucial step in the high-value utilization of lignin (VTM). In this study, a series of Ni/PB catalysts were synthesized using pseudoboehmite (PB) as a carrier. Changes in the valence states of Ni were induced through H2 activation, while the impacts of reaction temperature, initial pressure, and catalyst addition were investigated based on the VTM process. The results revealed that PB exhibited a distinct mesoporous structure (average pore size of 5.8 nm), with Ni loaded in small particles size (3.88 nm). Ni species on the catalyst existed in a + 2-valence state, undergoing a change after H2 activation, with an increase in Ni0 promoting enhanced activity. The Ni/PB-450 catalyst exhibited excellent activity at 250&#176C for 3 hours (VAN conversion and MMP selectivity > 99%), and the catalyst demonstrated good durability, maintaining 99.1% VAN conversion and 80% MMP selectivity after two cycles. Combining the characterization and experimental results, the etherification and hydrogenation of VAN were identified as the primary reaction pathways. This study aimed to provide a new avenue for the high-value utilization of lignin and its derivatives through controlled catalyst preparation [ABSTRACT FROM AUTHOR]

Effects of the emulsifier type, hydrophilic-lipophilic balance (HLB) value, bio-oil ratio, ultrasonic power density, and ultrasonic time were tested relative to the physicochemical properties and stability of emulsified oils to broaden the use of bio-oil and overcome its defects. The results showed that the turbidity and stabilization times of the emulsified oils reached the maximum values of 184 NTU and 84 min (Span 80 and Tween 80), 191 NTU and 92 min (HLB value of 5), 280 NTU and 92 min (bio-oil ratio of 5%), 191 NTU and 81 min (ultrasonic power density of 0.96 w/mL), 273 NTU and 97 min (ultrasonic time of 20 min), respectively. When the bio-oil to methanol ratio was 1:1, the turbidity value of the emulsified oil reached a maximum value of 664 NTU and the stability time was greater than 24 h. The Fourier transform infrared (FTIR) analysis indicated that the emulsified oil did not delaminate after 30 d, and the uniformity and stability of the emulsified oil were improved. [ABSTRACT FROM AUTHOR]

A carbon-based solid acid catalyst was prepared from papermaking sludge via calcining followed by sulfonation with p-toluenesulfonic acid. The micromorphology of several catalysts were compared via SEM, FTIR, N2 adsorption-desorption, XPS, and UV spectrum. It was found that the micromorphologies of biochar surface modified with concentrated H2SO4, p-toluenesulfonic acid, and sulfanilic acid were different and closely related to the binding mechanism. The biochar and p-toluenesulfonic acid exhibited π-π* stacking and hydrophobic effects. The suitable pores and gaps on the biochar surface were the key to the loading of ptoluenesulfonic acid. However, no π-π* stacking and hydrophobic effects were observed between the biochar and sulfanilic acid. The amidation grafting of sulfanilic acid to the biochar surface could lift the restriction of surface pore structure. The catalytic performance of these catalysts was evaluated via fructose, glucose, and cellulose degradation to 5- hydroxymethylfurfural (HMF). The HMF yield from fructose, glucose, and cellulose was 92.9%, 60.7%, and 28.6%, respectively, with the carbonbased solid acid catalyst. The carbon-based solid acid catalyst prepared from papermaking sludge and p-toluenesulfonic acid has the following advantages: a simple process, is environmentally friendly, and has good catalytic performance; as such, it has the prospect of industrialization. [ABSTRACT FROM AUTHOR]

Despite the fascinating biology of lichens, such as the symbiotic association of lichenforming fungi (mycobiont) with their photosynthetic partners and their ability to grow in harsh habitats, lack of genetic tools manipulating mycobiont has hindered studies on genetic mechanisms underpinning lichen biology. Thus, we established an Agrobacterium tumefaciens-mediated transformation (ATMT) system for genetic transformation of a mycobiont isolated from Cladonia macilenta. A set of combinations of ATMT conditions, such as input biomass of mycobiont, co-cultivation period with Agrobacterium cells, and incubation temperature, were tested to identify an optimized ATMT condition for the C. macilenta mycobiont. As a result, more than 10 days of co-cultivation period and at least 2 mg of input biomass of the mycobiont were recommended for an efficient ATMT, owing to extremely slow growth rate of mycobionts in general. Moreover, we examined T-DNA copy number variation in a total of 180 transformants and found that 88% of the transformants had a single copy T-DNA insertion. To identify precise T-DNA insertion sites that interrupt gene function in C. macilenta, we performed TAIL-PCR analyses for selected transformants. A hypothetical gene encoding ankyrin repeats at its C-terminus was interrupted by T-DNA insertion in a transformant producing dark-brown colored pigment. Although the identification of the pigment awaits further investigation, this proof-of-concept study demonstrated the feasibility of use of ATMT in construction of a random T-DNA insertion mutant library in mycobionts for studying genetic mechanisms behind the lichen symbiosis, stress tolerance, and secondary metabolite biosynthesis. [ABSTRACT FROM AUTHOR]

Blue carbon ecosystems such as mangroves are natural barriers to resisting and alleviating the impact of storm surges and extreme catastrophic weather. Accurate and efficient determination of the aboveground biomass of mangroves is of great importance for the protection and restoration of blue carbon ecosystems and their response to climate change. This study proposes a light gradient boosting model (LGBM) based on particle swarm optimization (PSO) algorithm for feature selection. We constructed and verified the proposed model using 227 quadrat datasets from a field survey and Sentinel-1 and Sentinel-2 data. The determination coefficient (R² ) and root-mean-square error (RMSE) were used to evaluate the performance of the model. Compared with random forest(RF), K-nearest neighbourhood regression(KNNR), extreme gradient boosting(XGBR), LGBM, and other machine learning algorithms, the LGBM-PSO model achieves better results (R² = 0.7807, RMSE = 24.6864 Mgha-1), The predicted range of mangrove biomass is 4.623–206.975 Mgha-1 . Therefore, the use of multisource remote sensing data combined with the LGBM-PSO model can provide better prediction results of aboveground biomass of mangroves, thereby providing a new method for estimating the aboveground biomass of large-scale mangroves. [ABSTRACT FROM AUTHOR]