Evaluation of the potential of utilizing lactic acid bacteria and dairy wastewaters for methane production

The aim of this study was to assess the potential of utilizing Lactobacillus delbrüeckii spp. bulgaricus in order to improve the characteristics of dairy wastewater and produce biomethane. Nuclear magnetic resonance was utilized to assess the metabolites present in the unprocessed wastewater. It was determined that wastewater is a good source of important bio-refinery relevant compounds and therefore wastewater has a potential to be utilized during fermentation as nutrients source. Upon wastewater fermentation, the chemical oxygen demand and biological oxygen demand significantly decreased (respectively 97.0 and 97.8%). Protocols were tested for one- and two-stage fermentation. During the one-stage fermentation, lactic acid bacteria were not added to the wastewater. During the two-stage fermentation, acetogenesis and methanogenesis occurred separately with the addition of L. delbdueckii during the acetogenesis stage. The highest yield of methane was obtained from wastewater upon two-stage fermentation (76% two-stages compared to 38% one-stage). Therefore, L. delbrüeckii have the potential to be utilized to ferment dairy WWs and produce methane. Such treatment of wastewater not only produces methane, but also decreases the polluting effect of the waste streams, by reducing the chemical oxygen demand and biological oxygen demand to 0.199 and 0.031 g/l, respectively.

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Treatment of dairy wastewater by two-stage membrane operation with ultrafiltration and nanofiltration

Water Science & Technology ◽

10.2166/wst.2012.937 ◽

2012 ◽

Vol 65 (5) ◽

pp. 915-919 ◽

Cited By ~ 13

Author(s):

Yan-Wen Gong ◽

Hong-Xun Zhang ◽

Xue-Ni Cheng

Keyword(s):

Chemical Oxygen Demand ◽

Isoelectric Point ◽

Oxygen Demand ◽

Dairy Wastewater ◽

Membrane Process ◽

Two Stage ◽

Membrane Cleaning ◽

Long Term Experiments ◽

Protein Rejection

Treatment of dairy wastewater by a two-stage membrane process with ultrafiltration (UF) and nanofiltration (NF) was investigated. The results showed that the flux of UF was higher at pH = 4.6 than that at pH = 8 because the resistance of the fouling membrane was lower at the isoelectric point of protein (pH = 4.6) in UF operation. Protein rejection exceeded 99% by UF + NF operation. Lactose rejections were 98.5 and 54% for UF + NF90 and UF + NF270 respectively. Experiments on membrane cleaning showed that the fouling layer of UF and NF was mainly protein and casein which could be removed by aqueous NaOH with pH = 10. The result of long-term experiments showed that the chemical oxygen demand (COD) of NF90 permeates was below 70 mg/L consistently and the wastewater could be concentrated to 24% by a two-stage membrane process.

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Biological Treatment of Dairy Wastewater using Bio Enzyme from Citrus Fruit Peels

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.a1530.059120 ◽

2020 ◽

Vol 9 (1) ◽

pp. 292-295

Keyword(s):

Chemical Oxygen Demand ◽

Biological Treatment ◽

Fermentation Process ◽

Suspended Solids ◽

Oxygen Demand ◽

Citrus Fruit ◽

Total Suspended Solids ◽

Total Dissolved Solids ◽

Biological Oxygen Demand ◽

Dairy Wastewater

Wastewater is directly discharged into the ground or other water sources; it causes soil pollution and it affects the nature of the soil. Hence it is necessary to treat the wastewater before discharging. The objective is to treat the dairy wastewater using Bio Enzyme. Bio Enzyme is produced by the fermentation process of citric fruit peels, water, and jaggery. To reduce the time of the fermentation process, yeast is added into the Bio Enzyme. Then the parameters like Biological Oxygen Demand(BOD), Chemical Oxygen Demand(COD), Total Solids(TS), Total Dissolved Solids(TDS), Total Suspended Solids(TSS), pH, Alkalinity, Chlorides and Oil & Grease present in Dairy wastewater after the treatment using Bio Enzyme in different percentages (2%,4%&6%) were found. Then from the results the efficient percentage of Bio Enzyme for treating the Diary Wastewater was found.

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Optimization of the Production of ε-Poly-L-Lysine by Novel Producer Lactic Acid Bacteria Isolated from Traditional Dairy Products

BioMed Research International ◽

10.1155/2020/2145656 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8

Author(s):

Hamid Reza Samadlouie ◽

Shahrokh Gharanjik ◽

Zohreh Beygom Tabatabaie

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Dairy Products ◽

Lactobacillus Delbrueckii ◽

Rdna Sequencing ◽

Traditional Dairy Products ◽

Lactis Strain ◽

The One ◽

Central Composite ◽

Lactobacillus Delbrueckii Subsp

New strains of lactic acid bacteria (LAB) were isolated from different traditional dairy products. Six new strains named Lactobacillus delbrueckii strain A01, Lactobacillus delbrueckii subsp. bulgaricus strain D01, Lactobacillus delbrueckii subsp. bulgaricus strain E01, Lactococcus lactis strain G01, Lactobacillus delbrueckii strain C01, and Lactobacillus delbrueckii subsp. bulgaricus strain F01 were identified using 16S rDNA sequencing, morphological and biochemical traits. All strains have been registered in the National Center for Biotechnology Information (NCBI) with accession numbers MN611241.1, MN611300.1, MN611301.1, MN611303.1, MN611241.1, and MN611299.1, respectively. Having found ε-Poly-L-Lysine (ε-PL) in all strains isolated, Lactobacillus delbrueckii strain A01 was identified as an active producer of ε-Poly-L-Lysine (ε-PL). The one-factor-at-a-time method and central composite design were applied to optimize ε-Poly-L-Lysine (ε-PL). A predicted 200 ppm of ε-PL was obtained in the medium containing the lowest level of glucose, 25 g/l, and yeast extract, 6 g/l.

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Exopolysaccharides Produced by Lactic Acid Bacteria of Kefir Grains

Zeitschrift für Naturforschung C ◽

10.1515/znc-2002-9-1009 ◽

2002 ◽

Vol 57 (9-10) ◽

pp. 805-810 ◽

Cited By ~ 27

Author(s):

Ginka I. Frengova ◽

Emilina D. Simova ◽

Dora M. Beshkova ◽

Zhelyasko I. Simov

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Starter Culture ◽

Streptococcus Thermophilus ◽

Lactobacillus Helveticus ◽

Lactobacillus Delbrueckii ◽

Monomer Composition ◽

Kefir Grains ◽

The One ◽

Lactobacillus Delbrueckii Subsp

A Lactobacillus delbrueckii subsp. bulgaricus HP1 strain with high exopolysaccharide activity was selected from among 40 strains of lactic acid bacteria, isolated from kefir grains. By associating the Lactobacillus delbrueckii subsp. bulgaricus HP1 strain with Streptococcus thermophilus T15, Lactococcus lactis subsp. lactis C15, Lactobacillus helveticus MP12. and Sacharomyces cerevisiae A13, a kefir starter was formed. The associated cultivation of the lactobacteria and yeast had a positive effect on the exopolysaccharide activity of Lactobacillus delbrueckii subsp. bulgaricus HP1. The maximum exopolysaccharide concentration of the starter culture exceeded the one by the Lactobacillus delbrueckii subsp. bulgaricus HP1 monoculture by approximately 1.7 times, and the time needed to reach the maximum concentration (824.3 mg exopolysacharides/l) was shortened by 6 h. The monomer composition of the exopolysaccharides from the kefir starter culture was represented by glucose and galactose in a 1.0:0.94 ratio, which proves that the polymer synthesized is kefiran.

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Two-Stage Procedure for the Quantitative Determination of Autoprothrombin III Concentration and Some Applications

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655029 ◽

1967 ◽

Vol 18 (01/02) ◽

pp. 198-210 ◽

Cited By ~ 5

Author(s):

Ronald S Reno ◽

Walter H Seegers

Keyword(s):

Prothrombin Time ◽

Factor Vii ◽

Two Stage ◽

Pronounced Increase ◽

One Stage ◽

Assay Procedure ◽

Bovine Plasma ◽

The One ◽

Autoprothrombin C

SummaryA two-stage assay procedure was developed for the determination of the autoprothrombin C titre which can be developed from prothrombin or autoprothrombin III containing solutions. The proenzyme is activated by Russell’s viper venom and the autoprothrombin C activity that appears is measured by its ability to shorten the partial thromboplastin time of bovine plasma.Using the assay, the autoprothrombin C titre was determined in the plasma of several species, as well as the percentage of it remaining in the serum from blood clotted in glass test tubes. Much autoprothrombin III remains in human serum. With sufficient thromboplastin it was completely utilized. Plasma from selected patients with coagulation disorders was assayed and only Stuart plasma was abnormal. In so-called factor VII, IX, and P.T.A. deficiency the autoprothrombin C titre and thrombin titre that could be developed was normal. In one case (prethrombin irregularity) practically no thrombin titre developed but the amount of autoprothrombin C which generated was in the normal range.Dogs were treated with Dicumarol and the autoprothrombin C titre that could be developed from their plasmas decreased until only traces could be detected. This coincided with a lowering of the thrombin titre that could be developed and a prolongation of the one-stage prothrombin time. While the Dicumarol was acting, the dogs were given an infusion of purified bovine prothrombin and the levels of autoprothrombin C, thrombin and one-stage prothrombin time were followed for several hours. The tests became normal immediately after the infusion and then went back to preinfusion levels over a period of 24 hrs.In other dogs the effect of Dicumarol was reversed by giving vitamin K1 intravenously. The effect of the vitamin was noticed as early as 20 min after administration.In response to vitamin K the most pronounced increase was with that portion of the prothrombin molecule which yields thrombin. The proportion of that protein with respect to the precursor of autoprothrombin C increased during the first hour and then started to go down and after 3 hrs was equal to the proportion normally found in plasma.

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Standardization of Factor VIII – IV. Establishment of the 3rd International Standard for Factor VIII: C Concentrate

Thrombosis and Haemostasis ◽

10.1055/s-0038-1665290 ◽

1983 ◽

Vol 50 (03) ◽

pp. 697-702 ◽

Cited By ~ 14

Author(s):

T W Barrowcliffe ◽

A D Curtis ◽

D P Thomas

Keyword(s):

Factor Viii ◽

High Purity ◽

Collaborative Study ◽

World Health ◽

Current Standard ◽

Two Stage ◽

International Standard ◽

One Stage ◽

The One ◽

Health Organization

SummaryAn international collaborative study was carried out to establish a replacement for the current (2nd) international standard for Factor VIII: C, concentrate. Twenty-six laboratories took part, of which 17 performed one-stage assays, three performed two-stage assays and six used both methods. The proposed new standard, an intermediate purity concentrate, was assayed against the current standard, against a high-purity concentrate and against an International Reference Plasma, coded 80/511, previously calibrated against fresh normal plasma.Assays of the proposed new standard against the current standard gave a mean potency of 3.89 iu/ampoule, with good agreement between laboratories and between one-stage and two- stage assays. There was also no difference between assay methods in the comparison of high-purity and intermediate purity concentrates. In the comparison of the proposed standard with the plasma reference preparation, the overall mean potency was 4.03 iu/ampoule, but there were substantial differences between laboratories, and the two-stage method gave significantly higher results than the one stage method. Of the technical variables in the one-stage method, only the activation time with one reagent appeared to have any influence on the results of this comparison of concentrate against plasma.Accelerated degradation studies showed that the proposed standard is very stable. With the agreement of the participants, the material, in ampoules coded 80/556, has been established by the World Health Organization as the 3rd International Standard for Factor VIII :C, Concentrate, with an assigned potency of 3.9 iu/ampoule.

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Syme Ankle Disarticulation in Peripheral Vascular Disease and Diabetic Foot Infection: The One-Stage versus Two-Stage Procedure

Foot & Ankle International ◽

10.1177/107110079501600303 ◽

1995 ◽

Vol 16 (3) ◽

pp. 124-127 ◽

Cited By ~ 25

Author(s):

Michael S. Pinzur ◽

Douglas Smith ◽

Helen Osterman

Keyword(s):

Vascular Disease ◽

Peripheral Vascular Disease ◽

Diabetic Foot ◽

Stage Versus ◽

Peripheral Vascular ◽

Two Stage ◽

Diabetic Foot Infection ◽

One Stage ◽

The One

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Study on the Leakage and Inter-Stage Pressure Drop Characteristics of Two-Stage Finger Seal

Applied Sciences ◽

10.3390/app11052239 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2239

Author(s):

Hailin Zhao ◽

Hua Su ◽

Guoding Chen ◽

Yanchao Zhang

Keyword(s):

Pressure Drop ◽

Pressure Difference ◽

Radial Displacement ◽

Mean Square ◽

The Finite Element Method ◽

Axial Pressure ◽

Two Stage ◽

One Stage ◽

The One ◽

Lower Contact

To solve the high leakage and high wear problems faced by sealing devices in aeroengines under the condition of high axial pressure difference, the two-stage finger seal is proposed in this paper. The finite element method and computational fluid dynamics (FEM/CFD) coupling iterative algorithm of the two-stage finger seal is developed and validated. Then the performance advantages of two-stage finger seal compared to the one-stage finger seal are studied, as well as the leakage and the inter-stage pressure drop characteristics of two-stage finger seal are investigated. Finally, the measure to improve the inter-stage imbalance of pressure drop of two-stage finger seal is proposed. The results show that the two-stage finger seal has lower leakage and lower contact pressure than the one-stage finger seal at high axial pressure difference, but there exists an inter-stage imbalance of pressure drop. Increasing the axial pressure difference and the root mean square (RMS) roughness of finger element can aggravate the imbalance of pressure drop, while the radial displacement excitation of rotor has little influence on it. The results also indicate that the inter-stage imbalance of pressure drop of the two-stage finger seal can be improved by increasing the number of finger elements of the 1st finger seal and decreasing the number of finger elements of the 2nd finger seal.

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