ZHUWen-qiang,WENXue-zhe,LINHua-li,et al.Impact of High Salinity and Low pH on Candida Bioaugmentation for Candied Fruit Wastewater Treatment[J].China Water & Wastewater,2025,41(15):125-134.
Impact of High Salinity and Low pH on Candida Bioaugmentation for Candied Fruit Wastewater Treatment
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第41卷
Number:
第15期
Page:
125-134
Column:
Date of publication:
2025-08-01
- Keywords:
- candied fruit wastewater; acidity and high salinity; Candida; bioaugmentation; microbial community structure
- Abstract:
- Candied fruit wastewater represents a typical acidic and high salinity effluent. In practical treatment processes, it is commonly required to dilute the wastewater to decrease salinity and add alkali for pH adjustment, both of which contribute to relatively high treatment costs. In this study, a sequencing batch biofilm reactor (SBBR) was employed, and Candida, a yeast capable of thriving under high salinity and acid conditions while effectively increasing the pH of wastewater, was utilized as a bioaugmentation agent for the treatment of candied fruit wastewater. The performance of the reactor and the change in microbial community structure under varying pH and salinity conditions were systematically investigated. At the salinity of 3.5%, SBBR system achieved optimal performance when the initial pH was set to 4.0. Following treatment, the pH of wastewater increased to above 6.0, while the removal efficiencies of COD, TIN, and TP reached 83.2%, 72.2%, and 98.7%, respectively. Under varying initial pH conditions, distinct microbial community structures were formed in the SBBR. Specifically, in R1 (pH 4.0 and salinity 5.0%) and R4 (pH 4.0 and salinity 3.5%), the dominant genera were both Pseudooceanicola and Candida. In R2 (pH 2.6 and salinity 3.5%), the dominant genera were Acidovorax and Zygoascus, while in R3 (pH 3.3 and salinity 3.5%), the dominant genera included Oceanobacillus, Vibrio, and Candida. The correlation analysis of environmental factors indicated that pH was the predominant factor affecting the structure of microbial communities, whereas the increase in salinity exerted a relatively minor influence. The species interaction network highlighted the pivotal roles of Oceanobacillus within the bacterial network and Rhodotorula within the fungal network. In the acidic and high salinity environment, symbiosis and reciprocity predominantly drove interactions in the bacterial network, whereas predation and competition were the primary relationships shaping the fungal network.
Last Update:
2025-08-01