DOI: 10.18150/ixr9ve
title: Use of liquid swine manure as a growth medium in the production of duckweed (Lemna L.)

description: The aim of the scientific activity was to determine the effect of different concentrations of pig manure in the growth medium on the growth of duckweed, as well as to determine its chemical composition and the possibility of using it as a protein feed for animals. This dataset contains the results of the growth media on which duckweed was grown, as well as the chemical composition tests and other analyses conducted on duckweed.The experiment was conducted in a room in which the temperature was maintained at 23 ± 1ºC, with the duration of light : darkness as 16 : 8 h, and light intensity of 7000 lux. It was set up with 30 plastic dishes with a capacity of 14 liters, each filled with 12 liters of clean water (city water supply / tap water). A liquid fraction of pig manure was used as a medium for duckweed growth.Duckweed growth dynamics were monitored during the 30-day pot studies by counting the number of plants every 5 days. From the vessels with the highest duckweed yield (groups 2, 3, 4, 5) the entire crop was taken and subjected to chemical analysis. During the experiment (days 0, 10, 20 and 30), the following parameters were measured using a Combo 5IN1 model EZ-9909SP meter: pH, TDS (measuring the total amount of compounds dissolved in water), EC (measuring the electrical conductivity of the liquid), salinity and temperature of the growth media. The results are the average of three dishes for each repetition.The collected fresh duckweed was divided into two portions. In the first, the dry matter content was determined, and after drying (temperature 60ºC, time 12 h) total protein, crude ash, crude fat, crude fiber and minerals. The second portion was frozen. After thawing and freeze-drying, its carotenoid content, amino acid composition, fatty acids, and nitrates and nitrites were determined. The chemical composition of the duckweed was determined according to AOAC. Dry duckweed samples were homogenized and mineralized (HNO3, H2O2 and HCl) using a Model DK 20 instrument (VELP Scientifica, Usmate, Italy). The P content of duckweed was determined by the vanadomolybdophosphate method using a Genesys 10 UV-VIS spectrophotometer (ultraviolet light and visible light region) (Thermo Electron Corporation, Madison, WI, USA). The content of Ca, Mg, K, Na, Zn, Cu, Cd, Pb, Al and Cr in duckweed was determined using a SOLAAR atomic absorption spectrometer (AAS) (Thermo Elemental, Cambridge, UK). Carotenoids were separated and determined using an HPLC system (Dionex) equipped with a CoulArray electrochemical detector (ESA Inc, Chelmsford, MA, USA). Methylation of fatty acids was carried out using the transesterification method (ISO 5509:2000). Fatty acid concentrations were determined using an Agilent 7890 GC gas chromatograph (Agilent Technologies, Waldbronn, Germany), a flame ionization detector and a Varian Select FAME column (Varian, Agilent Technologies, Waldbronn, Germany) according to the methodology described by Puppel et al. (2013). Amino acid composition was determined according to the methodology described by Appenroth et al. (2018), and nitrate and nitrite levels were determined according to the methodology described by Mir (2009).The data deposited in the repository were saved in .xlsx format. Data containing information on measurements made in the growth medium, the growth dynamics of the duckweed, and analyses made on the duckweed (basic composition, macro, micronutrients and heavy metals, amino acids, fatty acids, and nitrate levels).