Biodegradation of Agro-industrial Waste

Abstract

The production of agro-industrial waste is growing worldwide and these wastes cannot be disposed on the ground without treatment. The objective of this work was to conduct composting process and anaerobic digestion of a mixture of agro-industrial waste (W), grape (GW), olive (OW) and tobacco (TW) waste. The composting process and anaerobic digestion of the mixture of GW, OW and TW in the ratio GW:OW:TW = 1:1:1.98 (dry matter) were carried out in column reactors with effective volume of 10 dm 3 and 124 cm 3 , respectively, during 21 days. The composting experiment was carried out under forced aeration, while anaerobic digestion was conducted without aeration at temperature of 37 °C in anaerobic digester. Three different anaerobic experiments were conducted, without inoculum (E1) and with different ratio of inoculum and waste (E2, E3). During 21 days of composting of agro-industrial waste, the obtained conversion was 50 %. The volume of biogas produced during 21 days in experiments E1, E2 and E3 was 256 cm 3 , 280 cm 3 and 162 cm 3 , respectively.

Recovery of phenolic compounds from agro-industrial by-products: Evaluating antiradical activities and immunomodulatory properties

“…By-products produced by industrial and food industries are usually fated to animal feeding, anaerobic digestion or compost production (Kucic et al, 2018). Nonetheless, these residues are still rich in health promoting bioactive molecules, such as fiber, phenolic acids, flavonoids and anthocyanins (Martins et al, 2017).…”

Design of a Bioreactor for Aerobic Biodegradation of Biowaste Based on Insight into Its Composition and Estimated Process Parameters

“…During the aerobic stabilization process of the biowaste by composting, substrate samples were taken regularly and the most important physicochemical parameters (C/N ratio, pH value, moisture, dry solid (DS) and volatile solid (VS) content) were determined on duplicate samples according to the Austrian standard methods for compost analysis [23], while the pH value was determined as previously described [24]. The concentration of CO 2 was determined by titration of excess 1 mol/L NaOH with 1 mol/L HCl [25].…”

Biodegradation of Acid Scarlet 3R by a New Salt-tolerant Strain Alcaligenes faecalis LJ-3: Character, Enzyme and Kinetics Analysis

“…Degradation experiments were carried out in 250-mL Erlenmeyer flasks containing 100 mL sterilized medium supplemented with azo dye, and the inoculation size (OD 600 0.8) was 2 % (v/v). To characterize the degradation efficiency of strain LJ-3, the effects of static anoxic/shaking conditions (160 rpm), carbon sources (glucose, maltose, sucrose, lactose, dextrin, fructose, and xylose), nitrogen sources (yeast extract, beef extract, peptone, urea, glycine, NH 4 NO 3 , and NaNO 3 ), initial pH (4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0), incubation temperature (15,20,25,30,35,40, 45, 50 °C), and salinity (5,10,15,20,25,30,50, 80 g L −1 NaCl) on the degradation of 100 mg L -1 Acid Scarlet 3R were individually monitored. To find out maximum dye degrading ability of strain LJ-3, different concentrations of Acid Scarlet 3R (100, 200, 400, 600, 800, 1000, 1500, 2000 mg L −1 ) were respectively tested.…”

“…Therefore, various technologies have been developed to treat azo dyes containing effluents. Compared with physicochemical processes such as adsorption, membrane separation, ion-exchange, coagulation, and oxidation, biological methods are better alternatives due to their lower cost, higher efficiency and less secondary pollution 4,5 .…”