Data from: Study of helminth eggs (Ascaris suum) inactivation by anaerobic digestion and electrochemical treatment
Data files
Apr 19, 2023 version files 27.96 KB
-
A._suum_PP_and_SM_CSV.csv
-
A.suum_statistical_data__file_PP_and_SM_CSV.csv
-
Biogas_composition_(CH4__CO2_and_H2S)_PP_and_SM_CSV..csv
-
Biogas_PP_and_SM_CSV.csv
-
pH-PP_and_SM_CSV.csv
-
README.md
-
Total_Solids_(TS)_and_Volatile_Solids_(VS)_PP_and_SM_CSV.csv
-
Volatile_Fatty_Acids_(VFA)_PP_and_SM_CSV.csv
Abstract
The use of insufficiently treated wastewater or fecal sludge in agriculture raises concerns because of the pathogen content. Helminth eggs are one of the most crucial pathogens for ensuring public health and safety. Widely used disinfection treatment methods do not guarantee the complete inactivation of helminth eggs. The current study evaluated the effectiveness of anaerobic digestion and electrochemical process for helminth (Ascaris suum) egg inactivation. Lab-scale biochemical methane potential (BMP) assay was conducted by spiking A. suum eggs in a serum bottle. Total solid (TS), volatile solid (VS), pH, biogas production and its composition, and volatile fatty acids (VFA) were analyzed along with A. suum inactivation, every 3rd day for the initial 15 days and 5th day till 45 days. The results documented 98% inactivation of A. suum eggs (0.15 eggs/ml) in 35 days and remained at 0.14 eggs/ml till the 45th day. Correlation analysis revealed positive relation of non-viable eggs with pH and a negative relationship with all the other parameters. In the second set of experiments, a hypochlorite (4700ppm) solution was generated by electrolysis of aqueous NaCl solution in a membrane-less electrochemical cell. The hypochlorite was diluted (940, 470, 235, and 156ppm) in wastewater, spiked with A. suum eggs and then examined for inactivation at regular intervals. 10% inactivation was achieved at 940ppm concentration in 24h. This study revealed that the inactivation of A. suum eggs by anaerobic digestion or electrochemical treatment is a combined effect of more than one parameter.
Methods
The manuscript contains comprehensive information on data collecting, and the README.txt file contains detailed descriptions of each data file, which are briefly outlined here:
1. METHODS
Anaerobic Digestion- BMP (Biochemical Methane Potential) Assay
1.1 Experimental setup
The BMP assay was performed in serum bottles for the co-digestion of faecal sludge and food waste. Each bottle was subjected to a loading rate of biomass of 1.5kg VS/m3. Macro and micronutrients, Na-bicarbonate, digested from an anaerobic pilot reactor was used as inoculum, and the final volume was raised to 100ml by adding distilled water. A. suum eggs were procured from Excelsior Sentinel, USA, a mixture of viable and non-viable eggs, and spiked into the bottles. The experiment was performed using two bottles in each set; one bottle from each set was taken out at each sampling point for analysis, and another bottle along with the remaining bottles from the set was used to take the gas reading every day. The setup was maintained at room temperature (28 ± 2°C).
1.2 Parameter analysis
The different experimental parameters (pH, TS, VS, CH4, CO2, H2S, VFA and Helminth eggs) analyzed along with the method used are given in Table 1. Biogas production was estimated daily by measuring the gas volume generated using a water displacement unit. VFA analysis was conducted using the titration method
Helminth eggs were analysed by UKZN PRG helminth method, which included filtration, sedimentation, and centrifugation. Using the ZEISS Primo Star microscope, eggs were observed and counted. Images were captured by using Cockpit software which comes with the microscope.
All parameters were examined in duplicate every 3rd day for the first 15 days, then every 5th day till 45 days.
1.3 Statistical analysis
All the data were checked for normality and homogeneity of variance. The relationship between A. suum inactivation and all the other parameters was studied using correlation analysis. Statistical tests were performed using SPSS (IMB SPSS Statistics 25) software.
2. Electrochemical treatment for Helminth egg inactivation
The laboratory-scale electrochemical cell (EC) was set up in a 1000 ml beaker. A titanium plate was used as an anode electrode. The cathode electrode was made of SS 304 stainless-steel mesh. To apply a consistent voltage, a variable DC supply unit was used. The electrochemical cell solution was continuously mixed with a magnetic stirrer to generate hypochlorite, which was then employed as a disinfectant for the inactivating A. suum eggs.
In this study, hypochlorite was generated by electrolysis of 2 % NaCl solution. Electrolysis was performed for 2 hours, producing 4700ppm hypochlorite. The generated hypochlorite was diluted in various ratios with distilled water. Helminth eggs were spiked into all diluted solutions, and helminth inactivation was observed under a microscope after 15 minutes, 30 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, and 24 hours.
Usage notes
For a description of the uploaded data, files, and script, see README.txt.
In summary, there are total twelve data files.
Files pH-PP and SM_CSV, Total Solids (TS) and Volatile Solids (VS)_PP and SM_CSV, Volatile Fatty Acids (VFA)_PP and SM_CSV, Biogas_PP and SM_CSV, Biogas composition (CH4, CO2 and H2S)_PP and SM_CSV, A. suum_PP and SM_CSV contains details of pH, TS VS, VFA, Biogas, Biogas composition, and Ascaris suum data respectively. File number seven [A.suum statistical data file_PP and SM_CSV] contains data used for statistical significance and correlation analysis. File number eight [A. suum stat data output file_PP and SM] is output of the statistical significance and correlation data. File number nine and ten README.txt File_PP and SM and README.md contains information on methodology and experimental setup. File eleven and twelve Supporting figures_PP and SM and Supporting tables_PP and SM contain figures and tables respectively.