## 4 Conclusions  
One promising local fungal strain, NU-27, was isolated and identified as _L. ornata_, with a high decolorization to ADPE through fungal pretreatment in an airlift bioreactor. Five-fold low-diluted ADPE pretreated by NU-27 for 3 days was the optimum medium for the growth of the NH4\({}^{+}\)-tolerant algal strain, compared with other dilution treatments. Subsequently, initial OD as 0.3 and pH of 9.0 were optimal conditions for the algal strain to provide the maximum algal yield (OD = 2.1) and nutrient removal (88%, 58%, 65%, and 77% for NH4\({}^{+}-\)N, TN, TP, and COD removal rates) from the pretreated ADPE. This study demonstrated that the integrated process-optimization strategy of fungal decolorization of ADPE and subsequent microalgae cultivation may could be a promising approach to algal biomass production and nutrient removal from ADPE. Figure 8: Concentrations of ammonium nitrogen (NH4\({}^{+}-\)N: (a)), total nitrogen (TN: (b)), total phosphorus (TP: (c)), and chemical oxygen demand (COD: (d)) for NCU-39 in different initial pH treatments in 5-fold diluted anaerobic digestion piggery effluents (ADPEs) pretreated by 3-day fungal decolorization. Tap medium was used as a control. Error bars represent standard deviations (\(n=3\)). Different letters indicate significant differences with Tukey–Kramer post hoc tests (\(p<0.05\)). The information are available online at [[https://www.mdpi.com/article/10.3390/app12094741/s1](https://www.mdpi.com/article/10.3390/app12094741/s1)]([https://www.mdpi.com/article/10.3390/app12094741/s1](https://www.mdpi.com/article/10.3390/app12094741/s1)). J.Q. : Conceptualization, Investigation, Methodology, Formal analysis, Data curation, Writing--original draft, Writing--review and editing, Funding acquisition. J.Z. : Conceptualization, Investigation, Methodology, Formal analysis, Data curation, Writing--review and editing. Z.J. : Methodology, Software, Investigation, Visualization. J.C.: Formal analysis, data curation. J.L. ([PERSON]): Formal analysis, data curation. H.S. : Formal analysis. Q.L. : Writing--review and editing. H.L. : Writing--review and editing. T.W. : Methodology. S.F. : Data curation. J.L. ([PERSON]): Conceptualization, Formal analysis, Writing--review and editing. W.Z. : Conceptualization, Formal analysis, Writing--review and editing, Funding acquisition. All authors have read and agreed to the published version of the manuscript. This work was supported by the Key Research Development Program of the Jiangxi Province of China, grant numbers 20182 ABC28006, 20181 BBH80004, and 20212 BBF61010, and the National Natural Science Foundation of China, grant numbers 31960734 and 32160867. Not applicable. No conflicts, informed consent, or human or animal rights are applicable to this study. We would like to thank [PERSON] for data analysis. * _[PERSON] et al. (2017)_ [PERSON]; [PERSON]; [PERSON] Growth of microalgae on Undiluted Anaerobic Digestate of Piggery Effluent with High Ammonium Concentrations. _Algal Res._**2017**, _24_, 218-226. [CrossRef]
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