Dairy Industry Effluent Research Articles

Optimization of Protease Production by Bacillus isronensis Strain KD3 Isolaed from Dairy Industry Effluent

Optimization of Protease Production by Bacillus isronensis Strain KD3 Isolaed from Dairy Industry Effluent

Xanthomonas campestris biocontrol agent: Selection, medium formulation and bioprocess kinetic analysis

Black rot, caused by Xanthomonas campestris pv. campestris, is one of the most important diseases of cruciferous crops which causes significant yield losses. Biological control of black rot by microbial biocontrol agents represents a promising alternative to chemical treatments and good agricultural practices which show only limited success. This study was carried out to assess a potential of different antagonists, including Bacillus, Pseudomonas, Lactobacillus, Streptomyces, Saccharomyces and Trichoderma genera, for biological control of black rot. Cultivation broth samples and their filtrates were examined against seven X. campestris strains, isolated from diseased cruciferous plants, using the diffusion-disc method. Bacillus velezensis has showed the highest inhibition zone diameter of 35.62?3.76 mm. Afterwards, different combinations of carbon and nitrogen sources were used in the cultivation medium to maximize antagonistic activity of B. velezensis. The best combinations were glycerol and yeast extract, lactose and peptone, as well as sucrose and yeast extract, suggesting the potential of biodiesel, dairy and sugar industry effluents in the production of bioactive compounds effective against the black rot pathogen. The validation experiment was performed in a laboratory-scale bioreactor, in order to investigate bioprocess kinetics of biomass growth and carbon source consumption, using the cultivation medium containing the optimal carbon and nitrogen source.

Adsorptive removal of nitrate from wastewater using modified lignocellulosic waste material

Waste lignocellulosic material, namely brewers' spent grain (BSG), was modified by quaternisation, where amino groups were introduced into BSG via the reaction with N,N-dimethylformamide (DMF) and epichlorohydrin. The applicability of the modified BSG (MBSG) for the removal of nitrate ions from model solutions and wastewater was evaluated in batch adsorption experiments. Adsorption of nitrate to the MBSG was confirmed by FTIR analysis of the saturated/spent adsorbent. Fixed bed adsorption column and regeneration studies were performed to determine the regeneration capacity of MBSG. The MBSG had a maximum nitrate adsorption capacity of 22.65 mg g−1 for model nitrate solution, 18.22 mg g−1 for model wastewater and 14.4 mg g−1 for the real wastewater effluent generated from dairy industry. The analysis of the equilibrium data showed that the Freundlich isotherm model provided a slightly better fit to the obtained data than the Langmuir model, indicating multilayer sorption. The data were further analysed by pseudo-first-order and pseudo-second-order kinetic models, and the results revealed that the adsorption followed pseudo-second-order kinetics. The intraparticle diffusion model was used to interpret the mechanism of adsorption, and the results suggest that intraparticle diffusion was not the only process that controlled the adsorption. The adsorption-desorption studies in fixed bed column indicated that MBSG could be regenerated and reused for more than three cycles when model nitrate solutions were used. However, when real dairy industry effluent was used in the fixed bed experiments, the clogging of the column occurred. The applied modification technique was found to be appropriate yielding an effective adsorbent for selective nitrate removal from water.

Agro-potentiality of dairy industry effluent on the characteristics of Oryza sativa L. (Paddy)

Abstract This research aimed at analysingthe agronomical characteristics of Oryza sativa L. under irrigation with different concentrations of dairy industry effluent such as 25%, 50%, 75%, and 100% along with control. The studies revealed that the effluent is rich in some nutrients and altered the agronomical characteristics of Oryza sativa L. and physio-chemical properties of the soil as well. On treatment of soil with various effluent concentrations up to 30 days of harvesting, there was a significant impact on the moisture content, porosity, water holding capacity, bulk density, organic carbon, humus, phosphorous, potassium, calcium, chloride and nitrogen and insignificant effect on temperature, pH, conductivity and salinity. The agronomical parameters such as seed germination, shoot length, root length, total growth of plant, total fresh weight and dry weight of paddy seedlings were recorded to be improved at lower concentrations of effluent i.e. till 50% as compared to control. Moreover, the seedlings irrigated with low concentrations of effluent increased nitrogen and chlorophyll content in plants. Interestingly, the use of dilution containing 50% effluent permitted the growth of superior quality plants during early seedling growth phase. The results suggest that dairy industry effluent can be reused to cultivate paddy, enabling a successful agriculture practice and reducing environmental effects of improper effluent disposal to open land or water resources.

Optimization of a single chamber microbial fuel cell using Lactobacillus pentosus: Influence of design and operating parameters

Microbial fuel cells (MFCs) have been receiving an increased attention over the last years due to their potential to combat two global problems: waste pollution and energy demand. Additionally, when a wastewater is used, MFCs can perform its treatment while recovering energy, leading to the possibility of energy-producing wastewater treatment plants, offsetting their operational costs. However, to overcome their current limitations (lower power outputs and higher costs), a clear understanding of the effect of operation and design parameters on its overall performance is mandatory. Therefore, the goal of this work was to evaluate the effect of operating conditions - batch cycle and yeast extract concentration, and design parameters - anode electrode area, membrane thickness and active area, on the overall performance of a single chamber MFC. The MFC operated with a pure culture of Lactobacillus pentosus and a synthetic wastewater based on a real dairy industry effluent. The overall performance was evaluated through the power output and the COD removal rate. Additionally, the biofilm formed at the anode electrode was characterized in terms of biomass, proteins and polysaccharides content. For the conditions used in this work, a maximum power density of 5.04 ± 0.39 mW/m2 was achieved with an anode electrode area of 61 cm2, a batch cycle of 48 h, 50 mg/L of yeast extract and a Nafion 212 membrane with an active area of 25 cm2. The different conditions tested had a clear effect on the MFC energy production and biofilm characteristics, but not on the ability of L. pentosus to treat the dairy wastewater. The COD removal rates were in the range between 42% and 58%, for all the conditions tested.

Screening of quorum quenching activity of the bacteria isolated from dairy industry waste activated sludge

Intercellular bacterial communication process via exchange of signalling molecules acyl homoserine lactone results in various group activities like bioluminescence, antibiotic production, biofilm formation, sporulation, and virulence. The signalling molecules are targeted, and the communication is interrupted by a group of bacteria termed quorum quenching bacteria. The present study aims to isolate the quorum quenching bacteria from the waste activated sludge collected from the dairy industry effluent treatment plant and explore for its quorum quenching potential. The bacteria were cultured in the KG medium containing n-hexanoyl homoserine lactone as a sole source of carbon and nitrogen. The isolates were identified by the 16S ribosomal deoxyribonucleic acid analysis and subsequently were evaluated for its quorum quenching activity through Chromobacterium violaceum CV026 biosensor assay. The n-hexanoyl homoserine lactone degradation was quantified by GC–MS analysis. The 16S ribosomal deoxyribonucleic acid analysis revealed the isolated bacteria as Klebsiella pneumoniae (JYQ1 and JYQ5), Acinetobacter baumannii JYQ2, Pseudomonas nitroreducens JYQ3, and Pseudomonas JYQ4. The biosensor strain assay and GC–MS analysis indicated that all the isolates possessed an inherent ability to degrade N-hexanoyl homoserine lactone. The strain Pseudomonas JYQ4 exhibited the highest quorum quenching activity of 84 ± 3.3% within 6 h of incubation. The strain A. baumannii JYQ2 acted both as quorum sensing and as quorum quenching bacteria as evidenced by the decrease in quorum quenching from 79 ± 3.1 to 76.8 ± 2.5%.

Hydrogen production by co-digesting cheese whey and glycerin in an AnSBBR: Temperature effect

Anaerobic processes are strongly influenced by temperature and there is considerable disagreement about the ideal or even an ideal range of temperature for biological hydrogen production. Hence, this paper was designed to study the temperature effect in the mesophilic range (20, 25, 30 and 35 °C) on biohydrogen production in AnSBBR (anaerobic sequencing batch biofilm reactor) that co-digested dairy industry effluent (cheese whey) and biodiesel production effluent (glycerin). Influence of the inoculum heat shock pretreatment and micronutrients solution added to influent were also assessed. The best condition for hydrogen production was at the temperature of 30 °C, in which it was achieved a productivity of 129.0 molH2. m−3.d-1 and a yield of 5.4 molH2.kgCOD-1. Both micronutrient solution and inoculum pretreatment were proven necessary for a better hydrogen productivity. Productivity increased until 30 °C, but at 35 °C the exacerbated amount of biomass produced caused a rapid decrease in hydrogen production. From the kinetic model, it was observed that the majority of hydrogen production comes from the acidogenesis phase (k1H = 1.4 h-1, k3H = 1.4 h-1, k4H = 1.4 h-1). The calculated kinetic constants were used to estimate the activation energy of each reaction of the acidogenesis phase by using the Arrhenius model: 110–220 kJ.mol-1.

Isolation, purification and characterization of PHB producing strains from dairy industry effluent

Isolation, purification and characterization of PHB producing strains from dairy industry effluent

Cultivation of Ascochloris sp. ADW007-enriched microalga in raw dairy wastewater for enhanced biomass and lipid productivity

A potential microalgal strain was isolated from dairy industrial effluent contaminated water and genetically identified as a close relative of Ascochloris sp. The current study demonstrates growth, biomass and lipid productivity of Ascochloris sp. ADW007 and simultaneous bioremediation of raw dairy waste water (RDW). Indoor microalgal cultivation studies were conducted in controlled conditions of light and temperature, while outdoor pilot-scale experiments were performed in errant conditions using semi-cylindrical barrel shaped open troughs. The rate of biomass productivity of ADW007 was improved with RDW as growth nutrient in indoor bench-scale (0.102 ± 0.003 g/L/d) and outdoor pilot-scale cultivations (0.207 ± 0.003 g/L/d) when compared with the algal growth in synthetic BG 11 medium (0.086 ± 0.004 g/L/d) and TAP medium (0.099 ± 0.003 g/L/d), respectively. Similarly, in outdoor conditions, the lipid content reached maximum to 34.98 ± 0.21% with volumetric and areal lipid productivities of 0.072 ± 0.001 g/L/d and 9.63 ± 0.08 g/m2/d, respectively. With this, the estimated annual algal oil production is nearly 20,495 ± 1953 gallons/acre/yr, if cultivated throughout the year. C18:0/C18:1 were the predominant fatty acids in lipid which indicates a great potential of ADW007 for biodiesel production and simultaneous bioremediation processes using RDW. Post-harvesting process includes hollow fiber filtration followed by activated carbon treatment and resulted in 95.1, 79.7 and 98.1% reduction in chemical oxygen demand, nitrate and total phosphate, respectively.

Intensified recovery of lactose from whey using thermal, ultrasonic and thermosonication pretreatments

Recovery of valuable products such as proteins and lactose from dairy industry effluents offers promise due to the value addition and reduction in the environmental concerns attributed to lowering of the biological oxygen demand based on the recovery. The current work deals with understanding the effects of application of different pre-treatment schemes as thermal, sonication (only ultrasound) and thermosonication on the recovery of lactose from paneer (cottage cheese) whey using actual commercial samples of whey procured locally. Ultrasonic horn (20 kHz) with varying power levels over the range of 100 W–250 W has been used with different levels of ultrasonic exposure for sonication and thermosonication experiments. Ultrafiltration has been subsequently used for the separation of proteins and lactose from whey followed by anti-solvent sonocrystallization of lactose using ethanol. Combined pretreatment using ultrasound and heating resulted in maximum recovery of lactose as 94.59 ± 1.26%. Detailed understanding into the effect of different pretreatment conditions allowed for maximizing the recovery of lactose. Overall present work has clearly established that pretreatment using ultrasound in combination with heating results in enhanced recovery of lactose from whey.

Preparation of organo-modified kaolinite sorbents: The effect of surface functionalization on protein adsorption performance

Kaolinite organic derivatives were obtained by functionalization of kaolinite (kaol), in order to improve its removal capacity with respect to polypeptides present in dairy industry effluents. Functionalization was carried out by grafting two organosilanes, namely tert-butyldimethylchlorosilane (TBSCl) and 3-aminopropyltriethoxysilane (APTES), onto the kaol surface, and by intercalation of the small polar molecules dimethyl sulfoxide (DMSO) and potassium acetate. FTIR spectroscopy provided qualitative evidence about the presence of organosilane molecules grafted on the kaol outer surface, as well as information about the organo-kaol intercalates. Quantitative data about the amount of grafted or intercalated organic molecules was also obtained by means of elemental and thermogravimetric analysis. Textural characterization of the samples was carried out by N2 adsorption-desorption at 77K and by mercury intrusion porosimetry. SEM microscopy was used to study the microscopic topography. Protein adsorption experiments were carried out in batch mode, using bovine serum albumin (BSA) as a model protein to test the removal capacity of the materials obtained. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms for kaol and its organic-derivatives, respectively. The results obtained showed that surface functionalization of kaol considerably improved its protein removal capacity.

Impact of Dairy Industrial Effluent of Punjab (India) on Seed Germination and Early Growth of Triticum aestivum

Objectives: The aim of the present research was to study the impact of dairy industry effluent fertigation on agronomical characteristics of wheat (Triticum aestivum). Methods/Statistical Analysis: The treatments of such effluent, namely 0%, 25%, 50%, 75% and 100% were used for the cultivation of wheat. The effluent of such industry had significant amounts of nitrogen (28mg/l), phosphorous (13.10mg/l), potassium (168.2mg/l), copper (0.75mg/l), iron (<1mg/l) and nitrate (11.9mg/l) that may support plant growth. The effluent had no heavy metals like Cd, Co, Ni and Pb. Findings: The studies exposed that effluent at dilution of 50% showed the significant effect on seed germination percentage of 94.10 after seven days of irrigation. The shoot length (33.20cm), root length (12.90cm), total growth of plant (46.10cm), dry weight (0.57g), chlorophyll content (0.60) and nitrogen content (2.70%) were increased after one month of treatment with 50% concentration at lab scale. Significantly increased shoot length (48.35cm), root length (9.20cm), total growth of plant (57.55cm) and dry weight (0.71g) were observed maximum at concentration of 50% at pilot scale. The maximum agronomic performance of wheat was noticed with 50% concentration of dairy industry effluent. Application: The treated effluent of dairy industry had potential to be used as liquid fertilizer by mixing it with soil after appropriate dilution.

Supercritical water oxidation of lactose

AbstractNew data on total organic carbon (TOC) reduction and H2 production were obtained by using supercritical water oxidation of lactose with and without oxidant agents (H2O2 and t‐BHP) in a continuous Inconel 625 flow reactor. The oxidation reactions were carried out at 550 and 700 °C, 22.5 MPa, 0.025 g/g (2.5 wt%) lactose concentration, feed flow rate of 5 g · min−1, and a total reaction time of 90 min. The average production of H2 yielded 4.5 mol/mol lactose with TOC reduction of ∼99 %. The results obtained in this study with supercritical water oxidation (SCWO) may be used to generate energy via production of H2 from dairy industry effluents.

Pilot scale production, kinetic modeling, and purification of glycine betaine and trehalose produced from Actinopolyspora halophila (MTCC 263) using acid whey: A dairy industry effluent

Dairy factories manufacturing Greek yoghurt generate huge quantities of acid whey, an effluent which has serious ecological ramifications. In this work, we have used Actinopolyspora halophila (MTCC 263), an extreme halophile that utilized acid whey for pilot scale production of glycine betaine and trehalose which are commercially important compounds having innumerable applications in many industries. Batch bioreactor process with 200rpm agitation and 3vvm aeration gave a maximum production of 13.57±0.39gL−1 glycine betaine and 5.09±0.19gL−1 of trehalose. Kinetic models were also evaluated for production (biomass, glycine betaine and trehalose) and substrate utilization (lactose, glycine and total nitrogen) in A. halophila. Screening of resins for chromatographic separation of glycine betaine and trehalose showed strong cation exchange resin to be the most effective. The recovery of glycine betaine was 86.04±2.86% with purity of 82.26% and that of trehalose was 90.04±1.17% with purity of 94.47%. The findings of this work could benefit the dairy industries to plan on utilization of acid whey and generate revenue while simultaneously preventing environmental and economic repercussions caused by it.

A COMBINED ELECTROCOAGULATION-ELECTROOXIDATION TREATMENT FOR DAIRY WASTEWATER

Abstract - Dairy industry effluent is characterized by high chemical oxygen demand (COD) and other pollution load. This study addresses the elimination of organic compounds in dairy wastewater using electrocoagulation (EC), electrooxidation (EO) and a synergistic combination of EC and EO. The removal of COD, color and turbidity was investigated at various current intensities by using different electrodes and at various electrolysis times. Results show that EC is a relatively quick process (6 min), which is very effective in removing colloidal and suspended particles, as seen in changes in turbidity and color, but it is effective to eliminate only half of the COD. However, EO reduces 40% of COD in a practical time of about 30 min. To improve the removal of COD we proceeded to combine the two processes. Thus, the coupled process eliminates 60% of COD in a practical amount of time (21 min), removes the colloidal and suspended particles and eliminates color, turbidity, phosphorus, K + and NTK. The use of the seed toxicity test allows evaluating the quality and effectiveness of the studied effluent treatment system. Seed irrigated with raw waste or treated dairy effluent show no phytotoxicity.

Biological Processes as Promoting Way for Both Treatment and Valorization of Dairy Industry Effluents

Dairy industry effluents were usually characterized by their high organic matter content. Cheese whey is the most wide studied dairy reject. Though, the high polluting dairy wastewater including product losses and process effluents are also problematic and they need to be treated separately. Despite the quite efficiency of physico-chemical processes, polluting load removal is typically insufficient and the treatment should be completed by a biological process. Lactose bioconversion to single cell proteins; lactic acid; citric acid; biopolymer, bioethanol or even hydrogen seem to be promoting alternatives, not only for the treatment but also for the recovery of valuable products. Anaerobic digestion using dark and/or photofermentation and microbial fuel cells exhibited several advantageous comparing to the conventional dairy wastewater processing pathways. Then, the microbial material role for the bioconversion is crucial and it should be done according to the treatment purposes. Saccharomyces, Klyveromyces and Candida strains are widely used for dairy wastewaters polluting load removal. Lactic acid bacteria are used for their biotechnological proprieties. Some mixed cultures proved to result in more efficient treatment results with valuable products.

Utilization of Dairy Effluent for Food Grade Protease Production Using Bacillus &amp;lt;i&amp;gt;sp&amp;lt;/i&amp;gt;.

Food grade proteases are proteyolytic enzymes having application in baking, food processing, protein modification etc. As a commodity product, pressure on protease market is on prize reduction and increasing performance. Hence our objective was to isolate a potent protease-producing microorganism and formulate a cost effective medium for neutral protease synthesis by the potent microbial culture. In order to achieve the objective, a proteolytic bacterium was isolated from soil using milk agar medium and the bacteria was identified as <i>Bacillus</i> sp. by morphological and biochemical characterization. Dairy industry effluent was then studied as a medium for neutral protease synthesis by the potent bacteria. Supplementation of mineral salt to the medium did not show profound influence of environmental factors such as medium pH, incubation temperature, agitation rate and incubation time on enzyme production. Optimum enzyme titers were found at pH7 when incubated at 37°C and 120 rpm 48 h. Dairy industry effluent was thus found to be a cost effective medium for neutral protease synthesis by <i>Bacillus</i> sp.

Supercritical Water Gasification of Lactose as a Model Compound for Valorization of Dairy Industry Effluents

The dairy industry effluents, including whey waste and milk-based residues, are enriched in lactose and minor amounts of glucose that could potentially be converted to biofuels and biochemicals. Lactose was used in this work as a model compound of dairy effluents for gasification in supercritical water using a continuous flow tubular reactor. Four parameters impacting supercritical water gasification were studied, namely, temperature (550–700 °C), residence time (30–75 s), feed concentration (4–10 wt %), and catalyst concentration (0.2–0.8 wt %). The best total gas yields, carbon gasification efficiency, H2 yields, and other major gases (CO2 and CH4) were obtained at 700 °C using a feed concentration of 4 wt % lactose and a residence time of 60 s at fixed pressure of 25 MPa. Furthermore, catalytic lactose gasification involving 0.8 wt % Na2CO3 resulted in maximum H2 yield (22.4 mol/mol) compared to those obtained by 0.8 wt % K2CO3 (21.5 mol/mol) and noncatalytic gasification (16 mol/mol).

Rhodococcus lactis sp. nov., an actinobacterium isolated from sludge of a dairy waste treatment plant.

A Gram-stain-positive, non-motile and aerobic bacterium, designated strain DW151BT, was isolated from a sludge sample of a dairy industry effluent treatment plant. 16S rRNA gene sequence analysis of strain DW151BT placed it within the genus Rhodococcus. It displayed significant similarity with recognized species of the genus: Rhodococcus pyridinivorans PDB9T (98.8 %), Rhodococcus gordoniae W 4937T (98.6 %), Rhodococcus rhodochrous DSM 43241T (98.5 %) and Rhodococcus artemisiae YIM 65754T (97.5 %). However, strain DW151BT differed from phylogenetically closely related species in various phenotypic properties. The cellular polar lipid profile consisted of diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE) and phosphatidylinositol (PI) as major lipids, MK-8(H2) was the major menaquinone and meso-diaminopimelic acid was the cell-wall peptidoglycan. The fatty acid profile consisted of C16 : 0, C18 : 1cis9 and C16 : 1cis9 as main components. The presence of C16 : 0 and diphosphatidylglycerol as major fatty acid and polar lipid, respectively, was in accordance with chemotaxonomic markers of the genus Rhodococcus. The DNA G+C content of strain DW151BT was 69.9 mol%, a value within the limits reported for the members of this genus. Furthermore, strain DW151BT showed low similarity at the whole genome level in DNA-DNA hybridization experiments with phylogenetically closely related strains. Considering the low similarity at the genome level and differences in phenotypic properties, strain DW151BT is considered to represent a novel species of the genus Rhodococcus, for which the name Rhodococcus lactis sp. nov. is proposed. The type strain is DW151BT ( = MTCC 12279T = DSM 45625T).

&lt;bold&gt;The efficiency of electrocoagulation using aluminum electrodes&lt;/bold&gt;i&lt;bold&gt;n treating wastewater from a dairy industry&lt;/bold&gt;

&lt;p&gt;This research deals with the investigation of electrocoagulation (EC) treatment of wastewater from a dairy plant using aluminum electrodes. Electrolysis time, pH, current density and distance between electrodes were considered to assess the removal efficiency of chemical oxygen demand (COD), total solids (TS) and their fractions and turbidity. Samples were collected from the effluent of a dairy plant using a sampling methodology proportional to the flow. The treatments were applied according to design factorial of half fraction with two levels of treatments and 3 repetitions at the central point. The optimization of parameters for treating dairy industry effluent by electrocoagulation using aluminum electrodes showed that electric current application for 21 minutes, an initial sample pH near 5.0 and a current density of 61.6A m&lt;sup&gt;-2&lt;/sup&gt; resulted in a significant reduction in COD by 57%; removal of turbidity by 99%, removal of total suspended solids by 92% and volatile suspended solids by 97%; and a final treated effluent pH of approximately 10. Optimum operating condition was used for cost calculations show that operating cost is approximately 3.48R$ m&lt;sup&gt;-3&lt;/sup&gt;.&lt;/p&gt;