Welcoming you for any type of article submission for the upcoming issue on/before February 26, 2021.

Volume 2 Issue 2 - 2016
Effect of Illumination on the Metabolic Pathways in Anaerobic Digestion
Yiqing Yao*
Department of Biological Systems Engineering, Washington State University, USA
*Corresponding Author: Yiqing Yao, Department of Biological Systems Engineering, Washington State University, USA.
Received: January 12, 2016; Published: March 07, 2016
Citation: Yiqing Yao. “Effect of Illumination on the Metabolic Pathways in Anaerobic Digestion”. EC Bacteriology and Virology Research 2.2 (2016): 70-72.
Anaerobic digestion has been widely used for treating biomass wastes, for not only protecting environment, but also obtaining renewable energy. At present, we know that anaerobic methane yield can be carried out in darkness, but the knowledge of whether and how anaerobic methane yield was influenced by the illumination is still few.
As shown in Figure 1, during the process of anaerobic digestion, complex organic molecules are degraded into soluble organic molecules sugar, amino acids, and fatty acids by hydrolytic bacteria, which are then converted by acidogenic microorganisms into organic acids. Acetogenic bacteria then digest which into carbon dioxide, hydrogen and acetic acid; H2-producing bacteria also utilize some of which for H2 yield. Finally, methane produced from hydrogen, carbon dioxide and acetate.

Figure 1: Methanogenesis in anaerobic environments (Robert 2001).

For hydrogen-producing bacteria group of the hydrogen-acetic acid producing phase, there is a type of photosynthetic bacteria that can use light energy to break down small organic acids to generate hydrogen, such as purple non-sulfur (PNS) bacteria [1].
Hydrogen production is primarily influenced by nutritional and environmental factors, such as choice of carbon and nitrogen sources, the carbon to nitrogen ratio, pH levels, temperature, light intensity, wavelength of light, light-dark cycles and so on [2-4]. Yi., et al. [5] investigated the effect of illumination on cow manureand pig manure’s anaerobic digestion. The results shown that when theillumination conditions were at 0 hours (P1), 6 hours (P2), 12 hours (P3) and 24 hours (P4), the cumulative gas production of pig manure is 8136 mL, 857 mL, 15618.5 mL and 0 mL respectively. P3 > P1 > P2 > P4. The cumulative gas production of cow dung at 0 hours (C1),6 hours (C2), 12 hours (C3) and 24 hours (C4)of illumination is 3182.5 mL, 1244.5 mL, 7680 mL and 567.5 mL, respectively, C3 > C4 > C1 > C2. Chen., et al. [6] studied the effect of light on anaerobic digestion process of spartina alterniflora under 35°C. The results shown that biogas production was improved by 10.87% under illumination. The low improvement may be due to continuous illumination.
However, there is no reported study on the mechanism of how illumination affects the microbial community and then the biogas yield. Based on previous related studies and knowledge, the mechanism can be speculated (Figure 2): illumination can improve the activity and the breeding of photosynthetic bacteria, which lead to the decrease of intermediates from the stage of fermentation, then the improvement of activity and breeding of methanogens due to the reduced inhibition of intermediates; the increase of H2 from photosynthetic bacteria can alsoimprove the activity and breeding of methanogens as substrate. In another word, the illumination facilitates the coordination between H2-production/acetate-production stage and methanogenesis stage and then the improvement of biogas yield.

Figure 2: Pathway of the effect of illumination on biogas yield.

Based on the above, the following results can be anticipated:
1. The H2-producing bacteria will increase due to the illumination.
2. The methanogens will increase due to the increase of H2.
3. The increase of methanogens will lead to good coordination between H2-production/acetate-production stage and methanogen- esis stage.
4. Time used for reaching the stable status of AD will be short due to 1 and 2.
5. 1, 2 and 3 will result in the increase of biogas.
  1. Androga DD., et al. ““Optimization of temperature and light intensity for improved photofermentative hydrogen production using Rhodobactercapsulatus DSM 1710”. International Journal of Hydrogen Energy 39.6 (2014): 2472-2480.
  2. Uyar B., et al. “Effect of light intensity, wavelength and illumination protocol on hydrogen production in photobioreactors”. International Journal of Hydrogen Energy 32.18 (2007): 4670-4677.
  3. Özgür E., et al. “Biohydrogen production by Rhodobactercapsulatus on acetate at fluctuating temperatures”. Resources, Conservation and Recycling 54.5 (2010): 310-314.
  4. Androga DD., et al. “Factors affecting the longterm stability of biomass and hydrogen productivity in outdoor photofermentation”. International Journal of Hydrogen Energy 36.17 (2011): 11369-11378.
  5. Yi DM., et al. “Effect of illumination on pig manure and cow manure’s anaerobic digestion”. Journal of Agro-Environment Science 31.2 (2012): 428-434.
  6. Chen GY., et al. “Effect of light on anaerobic digestion process of spartina alterniflora”. Environmental Chemistry 28.5 (2009): 640-644.
Copyright: © 2016 Yiqing Yao. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

PubMed Indexed Article

EC Pharmacology and Toxicology
LC-UV-MS and MS/MS Characterize Glutathione Reactivity with Different Isomers (2,2' and 2,4' vs. 4,4') of Methylene Diphenyl-Diisocyanate.

PMID: 31143884 [PubMed]

PMCID: PMC6536005

EC Pharmacology and Toxicology
Alzheimer's Pathogenesis, Metal-Mediated Redox Stress, and Potential Nanotheranostics.

PMID: 31565701 [PubMed]

PMCID: PMC6764777

EC Neurology
Differences in Rate of Cognitive Decline and Caregiver Burden between Alzheimer's Disease and Vascular Dementia: a Retrospective Study.

PMID: 27747317 [PubMed]

PMCID: PMC5065347

EC Pharmacology and Toxicology
Will Blockchain Technology Transform Healthcare and Biomedical Sciences?

PMID: 31460519 [PubMed]

PMCID: PMC6711478

EC Pharmacology and Toxicology
Is it a Prime Time for AI-powered Virtual Drug Screening?

PMID: 30215059 [PubMed]

PMCID: PMC6133253

EC Psychology and Psychiatry
Analysis of Evidence for the Combination of Pro-dopamine Regulator (KB220PAM) and Naltrexone to Prevent Opioid Use Disorder Relapse.

PMID: 30417173 [PubMed]

PMCID: PMC6226033

EC Anaesthesia
Arrest Under Anesthesia - What was the Culprit? A Case Report.

PMID: 30264037 [PubMed]

PMCID: PMC6155992

EC Orthopaedics
Distraction Implantation. A New Technique in Total Joint Arthroplasty and Direct Skeletal Attachment.

PMID: 30198026 [PubMed]

PMCID: PMC6124505

EC Pulmonology and Respiratory Medicine
Prevalence and factors associated with self-reported chronic obstructive pulmonary disease among adults aged 40-79: the National Health and Nutrition Examination Survey (NHANES) 2007-2012.

PMID: 30294723 [PubMed]

PMCID: PMC6169793

EC Dental Science
Important Dental Fiber-Reinforced Composite Molding Compound Breakthroughs

PMID: 29285526 [PubMed]

PMCID: PMC5743211

EC Microbiology
Prevalence of Intestinal Parasites Among HIV Infected and HIV Uninfected Patients Treated at the 1o De Maio Health Centre in Maputo, Mozambique

PMID: 29911204 [PubMed]

PMCID: PMC5999047

EC Microbiology
Macrophages and the Viral Dissemination Super Highway

PMID: 26949751 [PubMed]

PMCID: PMC4774560

EC Microbiology
The Microbiome, Antibiotics, and Health of the Pediatric Population.

PMID: 27390782 [PubMed]

PMCID: PMC4933318

EC Microbiology
Reactive Oxygen Species in HIV Infection

PMID: 28580453 [PubMed]

PMCID: PMC5450819

EC Microbiology
A Review of the CD4 T Cell Contribution to Lung Infection, Inflammation and Repair with a Focus on Wheeze and Asthma in the Pediatric Population

PMID: 26280024 [PubMed]

PMCID: PMC4533840

EC Neurology
Identifying Key Symptoms Differentiating Myalgic Encephalomyelitis and Chronic Fatigue Syndrome from Multiple Sclerosis

PMID: 28066845 [PubMed]

PMCID: PMC5214344

EC Pharmacology and Toxicology
Paradigm Shift is the Normal State of Pharmacology

PMID: 28936490 [PubMed]

PMCID: PMC5604476

EC Neurology
Examining those Meeting IOM Criteria Versus IOM Plus Fibromyalgia

PMID: 28713879 [PubMed]

PMCID: PMC5510658

EC Neurology
Unilateral Frontosphenoid Craniosynostosis: Case Report and a Review of the Literature

PMID: 28133641 [PubMed]

PMCID: PMC5267489

EC Ophthalmology
OCT-Angiography for Non-Invasive Monitoring of Neuronal and Vascular Structure in Mouse Retina: Implication for Characterization of Retinal Neurovascular Coupling

PMID: 29333536 [PubMed]

PMCID: PMC5766278

EC Neurology
Longer Duration of Downslope Treadmill Walking Induces Depression of H-Reflexes Measured during Standing and Walking.

PMID: 31032493 [PubMed]

PMCID: PMC6483108

EC Microbiology
Onchocerciasis in Mozambique: An Unknown Condition for Health Professionals.

PMID: 30957099 [PubMed]

PMCID: PMC6448571

EC Nutrition
Food Insecurity among Households with and without Podoconiosis in East and West Gojjam, Ethiopia.

PMID: 30101228 [PubMed]

PMCID: PMC6086333

EC Ophthalmology
REVIEW. +2 to +3 D. Reading Glasses to Prevent Myopia.

PMID: 31080964 [PubMed]

PMCID: PMC6508883

EC Gynaecology
Biomechanical Mapping of the Female Pelvic Floor: Uterine Prolapse Versus Normal Conditions.

PMID: 31093608 [PubMed]

PMCID: PMC6513001

EC Dental Science
Fiber-Reinforced Composites: A Breakthrough in Practical Clinical Applications with Advanced Wear Resistance for Dental Materials.

PMID: 31552397 [PubMed]

PMCID: PMC6758937

EC Microbiology
Neurocysticercosis in Child Bearing Women: An Overlooked Condition in Mozambique and a Potentially Missed Diagnosis in Women Presenting with Eclampsia.

PMID: 31681909 [PubMed]

PMCID: PMC6824723

EC Microbiology
Molecular Detection of Leptospira spp. in Rodents Trapped in the Mozambique Island City, Nampula Province, Mozambique.

PMID: 31681910 [PubMed]

PMCID: PMC6824726

EC Neurology
Endoplasmic Reticulum-Mitochondrial Cross-Talk in Neurodegenerative and Eye Diseases.

PMID: 31528859 [PubMed]

PMCID: PMC6746603

EC Psychology and Psychiatry
Can Chronic Consumption of Caffeine by Increasing D2/D3 Receptors Offer Benefit to Carriers of the DRD2 A1 Allele in Cocaine Abuse?

PMID: 31276119 [PubMed]

PMCID: PMC6604646

EC Anaesthesia
Real Time Locating Systems and sustainability of Perioperative Efficiency of Anesthesiologists.

PMID: 31406965 [PubMed]

PMCID: PMC6690616

EC Pharmacology and Toxicology
A Pilot STEM Curriculum Designed to Teach High School Students Concepts in Biochemical Engineering and Pharmacology.

PMID: 31517314 [PubMed]

PMCID: PMC6741290

EC Pharmacology and Toxicology
Toxic Mechanisms Underlying Motor Activity Changes Induced by a Mixture of Lead, Arsenic and Manganese.

PMID: 31633124 [PubMed]

PMCID: PMC6800226

EC Neurology
Research Volunteers' Attitudes Toward Chronic Fatigue Syndrome and Myalgic Encephalomyelitis.

PMID: 29662969 [PubMed]

PMCID: PMC5898812

EC Pharmacology and Toxicology
Hyperbaric Oxygen Therapy for Alzheimer's Disease.

PMID: 30215058 [PubMed]

PMCID: PMC6133268

News and Events

December Issue Release

We always feel pleasure to share our updates with you all. Here, notifying you that we have successfully released the November issue of respective journals and the latest articles can be viewed on the current issue pages.

Submission Deadline for Upcoming Issue

ECronicon delightfully welcomes all the authors around the globe for effective collaboration with an article submission for the upcoming issue of respective journals. Submissions are accepted on/before December 19, 2022.

Certificate of Publication

ECronicon honors with a "Publication Certificate" to the corresponding author by including the names of co-authors as a token of appreciation for publishing the work with our respective journals.

Best Article of the Issue

Editors of respective journals will always be very much interested in electing one Best Article after each issue release. The authors of the selected article will be honored with a "Best Article of the Issue" certificate.

Certifying for Review

ECronicon certifies the Editors for their first review done towards the assigned article of the respective journals.

Latest Articles

The latest articles will be updated immediately on the articles in press page of the respective journals.