Yinli Bi, Hai Tan, Shishuang Zhang, Dongdong Wang, Jing Zhao
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引用次数: 0
Abstract
Dark septate endophytes (DSE) are widely used in ecological restoration. In this study, we first discovered that the metabolic products of the DSE strain Alternaria sp. 17463 contain extracellular polymeric substances (EPS). This study aimed to optimize the culture conditions, characterize the structural composition of EPS, and evaluate its effects on soil improvement. The ethanol precipitation method was used to extract EPS from the metabolites of Alternaria sp. 17463, increasing the yield 4.48-fold to 6.96 g L⁻1 through optimized cultivation conditions. The molecular mass of EPS was 533.754 kDa, with an exopolysaccharide content of up to 77.8% and a protein content of 8.4%. The EPS were mainly composed of glucan units T)-Glc p-(1 → and → 4)-Glc p-(1 → , with minor fractions of mannose and galactose. By acting as a cementing agent, EPS strengthened the linkages between soil particles. At an optimal concentration, it significantly enhanced the activity of extracellular enzymes involved in carbon, nitrogen, and phosphorus metabolism, thereby improving soil nutrient transformation and cycling. This also promoted changes in the metabolism of small molecules in the soil. This research reveals why this strain can accelerate ecological restoration and lays the foundation for further exploration of its metabolic products and potential applications in this field, particularly in open-pit dump reclamation and agricultural soil improvement.
期刊介绍:
Biotechnology Letters is the world’s leading rapid-publication primary journal dedicated to biotechnology as a whole – that is to topics relating to actual or potential applications of biological reactions affected by microbial, plant or animal cells and biocatalysts derived from them.
All relevant aspects of molecular biology, genetics and cell biochemistry, of process and reactor design, of pre- and post-treatment steps, and of manufacturing or service operations are therefore included.
Contributions from industrial and academic laboratories are equally welcome. We also welcome contributions covering biotechnological aspects of regenerative medicine and biomaterials and also cancer biotechnology. Criteria for the acceptance of papers relate to our aim of publishing useful and informative results that will be of value to other workers in related fields.
The emphasis is very much on novelty and immediacy in order to justify rapid publication of authors’ results. It should be noted, however, that we do not normally publish papers (but this is not absolute) that deal with unidentified consortia of microorganisms (e.g. as in activated sludge) as these results may not be easily reproducible in other laboratories.
Papers describing the isolation and identification of microorganisms are not regarded as appropriate but such information can be appended as supporting information to a paper. Papers dealing with simple process development are usually considered to lack sufficient novelty or interest to warrant publication.