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AbstractDespite recent studies, relatively few are known about the diversity of fungal communities in the deep Atlantic Ocean. In this study, we investigated the diversity of fungal communities in 15 different deep-sea sediments from the South Atlantic Ocean with a culture-dependent approach followed by phylogenetic analysis of ITS sequences. A total of 29 fungal strains were isolated from the 15 deep-sea sediments. These strains belong to four fungal genera, including Aspergillus, Cladosporium, Penicillium, and Alternaria. Penicillium, accounting for 44.8% of the total fungal isolates, was a dominant genus. The antiaflatoxigenic activity of these deep-sea fungal isolates was studied. Surprisingly, most of the strains showed moderate to strong antiaflatoxigenic activity. Four isolates, belonging to species of Penicillium polonicum, Penicillium chrysogenum, Aspergillus versicolor, and Cladosporium cladosporioides, could completely inhibit not only the mycelial growth of Aspergillus parasiticusmutant strain NFRI-95, but also the aflatoxin production. To our knowledge, this is the first report to investigate the antiaflatoxigenic activity of culturable deep-sea fungi. Our results provide new insights into the community composition of fungi in the deep South Atlantic Ocean. The high proportion of strains that displayed antiaflatoxigenic activity demonstrates that deep-sea fungi from the Atlantic Ocean are valuable resources for mining bioactive compounds.

The chlorinated nitroaromatic antibiotic chloramphenicol (CAP) is a refractory contaminant that is widely present in various environments. However, few CAP-mineralizing bacteria have been documented, and a complete CAP catabolism pathway has yet to be identified. In this study, the bacterial strain Sphingobiumsp. CAP-1 was isolated from an activated sludge sample and was shown to be capable of aerobically subsisting on CAP as the sole carbon, nitrogen, and energy source while simultaneously and efficiently degrading CAP. p-Nitrobenzoic acid (PNBA), p-nitrobenzaldehyde (PNBD), protocatechuate (PCA), and the novel side chain C3-hydroxy-oxygenated product of CAP (O-CAP) were identified during CAP degradation. Strain CAP-1 was able to convert O-CAP to intermediate product PNBA. The putative functional genes associated with PNBA catabolism into the tricarboxylic acid cycle via PCA and floc formation were also identified by genome sequencing and comparative proteome analysis. A complete pathway for CAP catabolism was proposed. The discovery of a novel CAP oxidation/detoxification process and a complete pathway for CAP catabolism enriches the fundamental understanding of the bacterial catabolism of antibiotics, providing new insights into the microbial-mediated fate, transformation, and resistance risk of CAP in the environment. The molecular basis of CAP catabolism and floc formation in strain CAP-1 also offers theoretical guidance for the enhanced bioremediation of CAP-containing environments.

ABSTRACTThe deep-sea bacterium strain FA13 was isolated from the sediment of the South Atlantic Ocean and identified as Bacillus circulansbased on 16S ribosomal DNA sequence. Through liquid fermentation with five media, the cell-free supernatant fermented with ISP2 showed the highest inhibition activities against mycelial growth of Aspergillus parasiticusmutant strain NFRI-95 and accumulation of norsolorinic acid, a precursor for aflatoxin production. Based on ISP2, uniform design was used to optimize medium formula and fermentation conditions. After optimization, the inhibition efficacy of the 20-time diluted supernatant against A. parasiticusNFRI-95 mycelial growth and aflatoxin production was increased from 0–23.1% to 100%. Moreover, compared to the original protocol, medium cost and fermentation temperature were significantly reduced, and dependence on seawater was completely relieved, thus preventing the fermentor from corrosion. This is the first report of a deep-sea microorganism which can inhibit A. parasiticusNFRI-95 mycelial growth and aflatoxin production.

3D gold brush nanoelectrode ensembles (BNEEs) consisted of gold nanowires 100 nm in diameter and 300 nm in length were fabricated by combining the technologies of template synthesis and controlled chemical etching of the membrane. The structure and morphology of the BNEEs was imaged by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The real active areas of BNEEs were found to be different when characterized by different redox species. The direct redox of daunorubicin (DNR) at the gold BNEEs exhibited absorption‐controlled characteristics and high current activity. BNEEs are reliable and effective in DNR detection.

Alzheimer's disease (AD), as a neurodegenerative disease that conceals the progressive development of early disease, has a long onset time and complicated etiology. As the number of Alzheimer's patients increases year by year, it is a hot issue that looking for effective drug prevention and treatment. As the king of Chinese herbal medicine, ginseng contains a variety of pharmacologically active substances, especially ginsenosides can affect multiple metabolic pathways in the body, and its efficacy is relatively complicated. This article reviews the pathogenesis of AD and the preventive effects of five ginsenosides such as Rg1, Rb1, Rg2, Rg5 and Rh1 on AD, in order to provide a basis for the development of functional foods for preventing AD.

Alginate is a linear, water-soluble acidic seaweed polysaccharide composed of L-guluronic acid and its C5 epimer D-mannuronic acid, a general term for hydrophilic derivatives of alginic acid. It is widely found in various brown algae. Alginate lyase and its enzymatic hydrolysate have a variety of biological activities and become a new research hotspot. This paper reviews the source, classification, enzymatic mechanism and enzymatic properties of alginate lyase, and summarizes the function and application of alginate lyase and its enzymatic hydrolysate brown algal oligosaccharide, in order to provide a base for the development and application of alginate lyase and its products.

In this study, the effects of aluminium oxide content, micro particle diameter and rotational speed on the activity of fermentation broth of deep-sea Penicillium MHE1 in inhibiting the growth of Aspergillus parasiticus NFRI-95 hypha and aflatoxin production were studied by uniform design. The optimal combination is obtained by regression analysis and experimental verification. The optimal combination is 1.015 g/L and 101.5 mesh in diameter for aluminium oxide, and 108.6 r/min for rotation incubation. Under these conditions, the mycelium inhibition rate of fermentation broth of strain MHE1 to Aspergillus parasiti NFRI-95 reached 85.88%, and the aflatoxin inhibition rate reached 100%, which increased by 7.1% and 9.2% respectively compared with that before optimization.