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Various types of natural marine products have excellent biological activities, which show great potential in the search for new therapeutic drugs and functional health care products. Brown algae are an economically important algae mainly cultivated in China and are also a good source of natural products. Polysaccharide are among the main active components of brown algae. Because of their complex compositions and structures, these polysaccharides possess a variety of biological activities, such as antioxidant, anti-inflammatory, immune regulatory, anti-tumor, antibacterial, anti-virus, and antidiabetic activities. Therefore, the extraction and biological activities of polysaccharides from brown algae have been widely examined in the field of development and utilization of marine biological resources. In this study, studies at home and abroad on the extraction methods and main biological activities of polysaccharides from brown algae in the past five years are reviewed. The advantages and disadvantages of various extraction methods are compared, and the biological functions and mechanisms of polysaccharides from brown algae are discussed. Possible influencing factors are analyzed, and current research on polysaccharides from brown algae is summarized to predict future research trends. This article provides a reference for promoting the production and application of polysaccharides from brown algae. [ABSTRACT FROM AUTHOR]

Background: Endophytes from ginseng plants may produce saponins through in vitro fermentation, and some saponins possess antioxidant activity. This study aimed to enhance the total saponin yield of an endophytic fungus isolated from wild ginseng, determine saponin types, and explore whether saponin extracts from optimized fermentation protocols have antioxidant activity. Methods: Umbelopsis dimorpha strain NSJG was fermented in liquid under different conditions. The types of saponins were analyzed by Liquid Chromatography/Mass Spectrometry (LC/MS). The antioxidant activity of saponin extracts was evaluated by measuring their hemolytic inhibition rate on erythrocytes. Results: The endophytic fungus strain NSJG produced 1.236 mg/mL total saponins through liquid potato dextrose (PD) fermentation. The total saponin concentrations of optimal protocols G-ED-8 (3.107 mg/mL) and G-DP-8 (2.045 mg/mL) were three times and twice that of G-PD. Saponin extracts from G-ED-8 and G-DP-8 contained seven and eight types of ginsenosides and had higher hemolysis inhibition rates on erythrocytes than Vitamin C (VC), which were 36.05% and 46.69%. Conclusions: The research highlights the potential implications of wild ginseng endophytic fungus strain NSJG for the in vitro production of ginsenosides and the development of novel antioxidants. [ABSTRACT FROM AUTHOR]

Aflatoxin B1 is a natural carcinogenic mycotoxin. The biological detoxification of aflatoxin could result in less environmental pollution, more moderate conditions, and less impact on food and feed, and be more convenient than physical and chemical methods. In this study, strain 13 with aflatoxin B1 degradation activity (67.47 ± 1.44%) was isolated and identified as Kocuria rosea. A uniform design was applied to optimize the degradation activity using a software Data Processing System, and a quadratic polynomial stepwise regression model was selected to investigate the relationships between the degradation rate and five independent variables. Furthermore, the optimal degradation conditions (culture temperature of 30 °C, culture time of 4.2 days, seawater ratio of 100%, pH of 7.11, and inoculation dosage of 0.09%) were verified with a degradation rate of 88 ± 0.03%, which was well matched with the predicted value (92.97%) of the model. Complete genome sequencing of Kocuria rosea, conducted with a combination of Illumina and single-molecule real-time sequencing, was used to analyze the genomic features and functions of the strain, which were predicted by the annotation based on seven databases, and may provide insights into the potential of Kocuria rosea, as well as providing a reference for degradation gene and protein mining. These results indicate that Kocuria rosea strain 13 has the ability to degrade aflatoxin B1 efficiently, and it also has the potential to provide aflatoxin-degrading enzymes. [ABSTRACT FROM AUTHOR]

Aflatoxin is natural toxin produced by fungi. It can be mainly classified as aflatoxin B, aflatoxin G, and aflatoxin M. To mankind and livestock, aflatoxins have high toxicity, teratogenicity, mutagenicity, and carcinogenicity. Compared to other aflatoxins, aflatoxin B1 is the most toxic. Aflatoxin B1 and aflatoxin M1 have been classified as Group 1 (established carcinogens to human) by International Agency for Research on Cancer. Therefore, how to detoxify aflatoxins has won increasing attention at home and abroad. This paper mainly expounded the physical methods, chemical methods, and biological methods for aflatoxin detoxification at home and abroad, laying emphasis on reviewing the varieties of biological methods for aflatoxin detoxification, detoxification mechanisms, and toxicity of degradation products. Before ending, the paper also prospected the future for research activities in this field. [ABSTRACT FROM AUTHOR]