The document discusses citric acid production using various substrates like sugarcane molasses and beet molasses. It summarizes 4 research articles on citric acid production through solid state fermentation and shake flask fermentation techniques. The articles study factors affecting citric acid yield like pH, sugar concentration, incubation time, metal ions, etc. The expected outcome is that sugarcane molasses would yield more citric acid than beet molasses due to its lower impurity content. Shake flask fermentation is considered more feasible than solid state fermentation. The project aims to estimate and compare the citric acid yields from sugarcane and beet molasses using different techniques.
introduction: Citric acid (C6H8O7) is a weak organic tricarboxylic acid found in citrus fruits (lemons, oranges, grapes, tomatoes, beets etc.)
Citric acid known as an intermediate of kreb's cycle, and hence present in all living organisms.
Citric acid is produced by three method fermentation, chemical synthesis and extraction from citrus fruits.
In 1782, Carl Wilhelm Scheele first obtained citric acid from lemon juice, but in 1923 Pfizer began operating a fermentation based process in the USA.
Uses: Used as flavoring agent in food industries.
Used in chemical industries (as an antifoam agent).
In pharmaceuticals industries (as Tri-sodium citrate as blood preservative).
In detergent industries (as strong cleaning agent).
As chelating and sequestering agent.
In production of carbonated beverages.
Used as antioxidant in frozen fruits and vegetables.
Various cosmetic product like lotion, shampoos, creams, and toothpaste.
Biosynthesis: The metabolic pathway involved in citric acid biosynthesis the TCA cycle or the Krebs cycle.
In TCA cycle critic acid is a intermediate product, glucose is predominant source of carbon for acid production.
In glycolysis glucose is converted in 2 molecules of pyruvate. Pyruvate form Acetyl CoA and Oxaloacetate which finally convert in citrate.
Citrate synthase is a regulatory enzyme for production of citric acid because the activity of this enzyme increases at the time of acid production, while activity of other enzymes that degrade the citrate are reduced.
Pyruvate dehydrogenase is also a key enzyme that converts pyruvate to oxaloacetate in citrate production.
type of fermentation: There are two types of fermentation:
Surface fermentation - Characterized by growing microorganisms as a layer or film on a surface in contact nutrient medium, which may be solid or liquid.
Submerged fermentation – In this process microorganisms are throughout the nutrient medium.
production of citric acid , acetic acid and gluconic acid...
CITRIC ACID.
Citric acid is a weak organic acid found in citrus fruits. It is naturally found in fruits such as lemon, orange, pineapple, plum, and pear.
- Molecular formula is C6H8O7 and belongs to the carboxylic acids groups.
- Stronger acid compared to other typical carboxylic acid.
Produced by fermentation and suitable pH is around 3-6. Citric acid is ( 2- hydroxy-1,2,3 propane tricarboxylic acid).
Citric acid is excreted from the cells in response to unfavorable intracellular condition caused by increased levels of tricarboxylic acids (TCA)
A crucial prerequisite for overflow of citric acid from A. niger cells is therefore increased level of Krebs cycle intermediates caused by anaplerotic reactions.
ACETIC ACID
• Acetic Acid is systematically named as ethanoic acid.
• It is a colorless liquid organic compound.
• It has a pungent/ vinegar-like odor.
• Glacial acetic acid is the pure form of acetic acid (99.98%).
• Vinegar is product of Acetic acid. The first vinegar was spoiled wine.
• It has melting point 16 to 17°C; 61 to 62°F.
GLUCONIC ACID.
Introduction:
Gluconic acid is an organic compound with molecular formula C6H12O7 and condensed structural formula HOCH2 (CHOH)4COOH.
It is one of the 16 stereoisomers of 2,3,4,5,6-pentahydroxyhexanoic acid. In aqueous solution at delicately acidic pH, gluconic acid forms the gluconate ion.
Gluconic Acid is the carboxylic acid formed by the oxidation of the first carbon of glucose with antiseptic and chelating properties.
Gluconic acid, found abundantly in plant, honey and wine, can be prepared by fungal fermentation process commercially. This agent and its derivatives can used in formulation of pharmaceuticals, cosmetics and food products as additive or buffer salts.
Aqueous gluconic acid solution contains cyclic ester glucono delta lactone structure, which chelates metal ions and forms very stable complexes. In alkaline solution, this agent exhibits strong chelating activities towards anions, i.e. calcium, iron, aluminum, copper, and other heavy metals.
Generally, organic acids are produced commercially either by chemical synthesis or fermentation. ... All organic acids of tricarboxylic acid cycle can be produced in high yields in microbiological processes. Among fermentation processes, the production of organic acids is dominated by submerged fermentation.
A yeast strain E2 was purified from traditional yeast, and retained for its strongly acidifying, fermentative and saccharolytic
power. In fact, this strain produces a high concentration of acetic acid 105.85 mg / L revealed by using the H.P.L.C DAD technique
during its growth in semi synthetic medium containing sucrose at 5 g /l as only carbon source. The pH of the culture medium increases
from 5.58 to 2.76 after 24 hours of culture and to 2.48 after 48 hours of
introduction: Citric acid (C6H8O7) is a weak organic tricarboxylic acid found in citrus fruits (lemons, oranges, grapes, tomatoes, beets etc.)
Citric acid known as an intermediate of kreb's cycle, and hence present in all living organisms.
Citric acid is produced by three method fermentation, chemical synthesis and extraction from citrus fruits.
In 1782, Carl Wilhelm Scheele first obtained citric acid from lemon juice, but in 1923 Pfizer began operating a fermentation based process in the USA.
Uses: Used as flavoring agent in food industries.
Used in chemical industries (as an antifoam agent).
In pharmaceuticals industries (as Tri-sodium citrate as blood preservative).
In detergent industries (as strong cleaning agent).
As chelating and sequestering agent.
In production of carbonated beverages.
Used as antioxidant in frozen fruits and vegetables.
Various cosmetic product like lotion, shampoos, creams, and toothpaste.
Biosynthesis: The metabolic pathway involved in citric acid biosynthesis the TCA cycle or the Krebs cycle.
In TCA cycle critic acid is a intermediate product, glucose is predominant source of carbon for acid production.
In glycolysis glucose is converted in 2 molecules of pyruvate. Pyruvate form Acetyl CoA and Oxaloacetate which finally convert in citrate.
Citrate synthase is a regulatory enzyme for production of citric acid because the activity of this enzyme increases at the time of acid production, while activity of other enzymes that degrade the citrate are reduced.
Pyruvate dehydrogenase is also a key enzyme that converts pyruvate to oxaloacetate in citrate production.
type of fermentation: There are two types of fermentation:
Surface fermentation - Characterized by growing microorganisms as a layer or film on a surface in contact nutrient medium, which may be solid or liquid.
Submerged fermentation – In this process microorganisms are throughout the nutrient medium.
production of citric acid , acetic acid and gluconic acid...
CITRIC ACID.
Citric acid is a weak organic acid found in citrus fruits. It is naturally found in fruits such as lemon, orange, pineapple, plum, and pear.
- Molecular formula is C6H8O7 and belongs to the carboxylic acids groups.
- Stronger acid compared to other typical carboxylic acid.
Produced by fermentation and suitable pH is around 3-6. Citric acid is ( 2- hydroxy-1,2,3 propane tricarboxylic acid).
Citric acid is excreted from the cells in response to unfavorable intracellular condition caused by increased levels of tricarboxylic acids (TCA)
A crucial prerequisite for overflow of citric acid from A. niger cells is therefore increased level of Krebs cycle intermediates caused by anaplerotic reactions.
ACETIC ACID
• Acetic Acid is systematically named as ethanoic acid.
• It is a colorless liquid organic compound.
• It has a pungent/ vinegar-like odor.
• Glacial acetic acid is the pure form of acetic acid (99.98%).
• Vinegar is product of Acetic acid. The first vinegar was spoiled wine.
• It has melting point 16 to 17°C; 61 to 62°F.
GLUCONIC ACID.
Introduction:
Gluconic acid is an organic compound with molecular formula C6H12O7 and condensed structural formula HOCH2 (CHOH)4COOH.
It is one of the 16 stereoisomers of 2,3,4,5,6-pentahydroxyhexanoic acid. In aqueous solution at delicately acidic pH, gluconic acid forms the gluconate ion.
Gluconic Acid is the carboxylic acid formed by the oxidation of the first carbon of glucose with antiseptic and chelating properties.
Gluconic acid, found abundantly in plant, honey and wine, can be prepared by fungal fermentation process commercially. This agent and its derivatives can used in formulation of pharmaceuticals, cosmetics and food products as additive or buffer salts.
Aqueous gluconic acid solution contains cyclic ester glucono delta lactone structure, which chelates metal ions and forms very stable complexes. In alkaline solution, this agent exhibits strong chelating activities towards anions, i.e. calcium, iron, aluminum, copper, and other heavy metals.
Generally, organic acids are produced commercially either by chemical synthesis or fermentation. ... All organic acids of tricarboxylic acid cycle can be produced in high yields in microbiological processes. Among fermentation processes, the production of organic acids is dominated by submerged fermentation.
A yeast strain E2 was purified from traditional yeast, and retained for its strongly acidifying, fermentative and saccharolytic
power. In fact, this strain produces a high concentration of acetic acid 105.85 mg / L revealed by using the H.P.L.C DAD technique
during its growth in semi synthetic medium containing sucrose at 5 g /l as only carbon source. The pH of the culture medium increases
from 5.58 to 2.76 after 24 hours of culture and to 2.48 after 48 hours of
"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...MMariSelvam4
The carbon cycle is a critical component of Earth's environmental system, governing the movement and transformation of carbon through various reservoirs, including the atmosphere, oceans, soil, and living organisms. This complex cycle involves several key processes such as photosynthesis, respiration, decomposition, and carbon sequestration, each contributing to the regulation of carbon levels on the planet.
Human activities, particularly fossil fuel combustion and deforestation, have significantly altered the natural carbon cycle, leading to increased atmospheric carbon dioxide concentrations and driving climate change. Understanding the intricacies of the carbon cycle is essential for assessing the impacts of these changes and developing effective mitigation strategies.
By studying the carbon cycle, scientists can identify carbon sources and sinks, measure carbon fluxes, and predict future trends. This knowledge is crucial for crafting policies aimed at reducing carbon emissions, enhancing carbon storage, and promoting sustainable practices. The carbon cycle's interplay with climate systems, ecosystems, and human activities underscores its importance in maintaining a stable and healthy planet.
In-depth exploration of the carbon cycle reveals the delicate balance required to sustain life and the urgent need to address anthropogenic influences. Through research, education, and policy, we can work towards restoring equilibrium in the carbon cycle and ensuring a sustainable future for generations to come.
UNDERSTANDING WHAT GREEN WASHING IS!.pdfJulietMogola
Many companies today use green washing to lure the public into thinking they are conserving the environment but in real sense they are doing more harm. There have been such several cases from very big companies here in Kenya and also globally. This ranges from various sectors from manufacturing and goes to consumer products. Educating people on greenwashing will enable people to make better choices based on their analysis and not on what they see on marketing sites.
Willie Nelson Net Worth: A Journey Through Music, Movies, and Business Venturesgreendigital
Willie Nelson is a name that resonates within the world of music and entertainment. Known for his unique voice, and masterful guitar skills. and an extraordinary career spanning several decades. Nelson has become a legend in the country music scene. But, his influence extends far beyond the realm of music. with ventures in acting, writing, activism, and business. This comprehensive article delves into Willie Nelson net worth. exploring the various facets of his career that have contributed to his large fortune.
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Introduction
Willie Nelson net worth is a testament to his enduring influence and success in many fields. Born on April 29, 1933, in Abbott, Texas. Nelson's journey from a humble beginning to becoming one of the most iconic figures in American music is nothing short of inspirational. His net worth, which estimated to be around $25 million as of 2024. reflects a career that is as diverse as it is prolific.
Early Life and Musical Beginnings
Humble Origins
Willie Hugh Nelson was born during the Great Depression. a time of significant economic hardship in the United States. Raised by his grandparents. Nelson found solace and inspiration in music from an early age. His grandmother taught him to play the guitar. setting the stage for what would become an illustrious career.
First Steps in Music
Nelson's initial foray into the music industry was fraught with challenges. He moved to Nashville, Tennessee, to pursue his dreams, but success did not come . Working as a songwriter, Nelson penned hits for other artists. which helped him gain a foothold in the competitive music scene. His songwriting skills contributed to his early earnings. laying the foundation for his net worth.
Rise to Stardom
Breakthrough Albums
The 1970s marked a turning point in Willie Nelson's career. His albums "Shotgun Willie" (1973), "Red Headed Stranger" (1975). and "Stardust" (1978) received critical acclaim and commercial success. These albums not only solidified his position in the country music genre. but also introduced his music to a broader audience. The success of these albums played a crucial role in boosting Willie Nelson net worth.
Iconic Songs
Willie Nelson net worth is also attributed to his extensive catalog of hit songs. Tracks like "Blue Eyes Crying in the Rain," "On the Road Again," and "Always on My Mind" have become timeless classics. These songs have not only earned Nelson large royalties but have also ensured his continued relevance in the music industry.
Acting and Film Career
Hollywood Ventures
In addition to his music career, Willie Nelson has also made a mark in Hollywood. His distinctive personality and on-screen presence have landed him roles in several films and television shows. Notable appearances include roles in "The Electric Horseman" (1979), "Honeysuckle Rose" (1980), and "Barbarosa" (1982). These acting gigs have added a significant amount to Willie Nelson net worth.
Television Appearances
Nelson's char
Artificial Reefs by Kuddle Life Foundation - May 2024punit537210
Situated in Pondicherry, India, Kuddle Life Foundation is a charitable, non-profit and non-governmental organization (NGO) dedicated to improving the living standards of coastal communities and simultaneously placing a strong emphasis on the protection of marine ecosystems.
One of the key areas we work in is Artificial Reefs. This presentation captures our journey so far and our learnings. We hope you get as excited about marine conservation and artificial reefs as we are.
Please visit our website: https://kuddlelife.org
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@kuddlelifefoundation
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and write to us if you have any questions:
info@kuddlelife.org
WRI’s brand new “Food Service Playbook for Promoting Sustainable Food Choices” gives food service operators the very latest strategies for creating dining environments that empower consumers to choose sustainable, plant-rich dishes. This research builds off our first guide for food service, now with industry experience and insights from nearly 350 academic trials.
Characterization and the Kinetics of drying at the drying oven and with micro...Open Access Research Paper
The objective of this work is to contribute to valorization de Nephelium lappaceum by the characterization of kinetics of drying of seeds of Nephelium lappaceum. The seeds were dehydrated until a constant mass respectively in a drying oven and a microwawe oven. The temperatures and the powers of drying are respectively: 50, 60 and 70°C and 140, 280 and 420 W. The results show that the curves of drying of seeds of Nephelium lappaceum do not present a phase of constant kinetics. The coefficients of diffusion vary between 2.09.10-8 to 2.98. 10-8m-2/s in the interval of 50°C at 70°C and between 4.83×10-07 at 9.04×10-07 m-8/s for the powers going of 140 W with 420 W the relation between Arrhenius and a value of energy of activation of 16.49 kJ. mol-1 expressed the effect of the temperature on effective diffusivity.
5. CITRIC ACID
• Citric acid (C₆H₈O₇) (2-hydroxy-1,2,3-propane
tricarboxylic acid) is a weak organic tricarboxylic
acid found in citrus fruits
• . Citric acid is found naturally in citrus fruits,
especially lemons and limes. It’s what gives
them their tart, sour taste.
• It has a monoclinic crystal structure.
• It is odourless and colourless compound.
6.
7. The industrial citric acid production can be
carried in three different ways:
• Surface fermentation
• Submerged fermentation
• Solid-state fermentation
9. The most common species involved
extensively in citric acid production in labs
is Aspergillus niger
10. Uses of Citric Acid
• It is used as an antioxidant
• It is used as a cleaning agent – as an ingredient in
kitchen and bathroom cleaning solution
• It is used as an emulsifying agent in ice creams
• It is used to add a sour taste to soft drinks and
other food items
• It used in shampoo
• It is used in sucrose crystallization in caramel
• It is used in food colouring
• It is used as a natural preservative
• It is used to remove the chalky deposit from
evaporators, kettles, boilers etc.
11. ARTICLE 01
Solid-state fermentation for
the synthesis of citric acid
by Aspergillus niger
Luciana P.S. Vandenberghe a,b, Carlos R. Soccola, Ashok
Pandeya, J.-M. Lebeault
12. • Sugarcane formation through solid state
method is carried out through three different
agro industrial wastes viz., sugarcane bagasse,
coffee rust and cassava bagasse.
• The main thing that they focussed on were
sugarcane bagasse efficiency of citric acid
production.
• Solid state method is one such method that
requires lower energy and produces much less
waste water and environmental concerns
because of the disposal of the solid substrate.
• SSF is by development of microorganisms in low
water environment.
13. • The results showed that citric acid production showed
more sugar consumption in Aspergillus niger : Coffee
rust(97%)>Sugarcane bagasse(90%)> Cassava
bagasse(87%).
• Citric acid production was found high in cassava with a
difference of 88g/kg by sugarcane.
14. • In sugarcane when the strain is mutant the
production of citric acid was 120g/l, while
parental produced 80g/l. (1.5 fold
improvement from 150g/l of molasses sugar).
• Period of citric acid production with wild type-
10days, while in mutant strain: 6-7days.
15. ARTICLE 02
Citric Acid Fermentation
by Aspergillus niger NG-
110 in Shake Flask
Rubina Mazhar, Sikander Ali, Abdul Waheed
Biotechnology Laboratory Government college
University, Lahore,Pakistan
16. • The aim of the experiment was to conduct a study on the
culture conditions for the production of citric acid by
mutant strain of Aspergillus niger NG-110 using shake
flask technique.
• Enhanced citric biosynthesis optimized by alcohol and
CaCl₂ was carried out. On comparison on kinetic
parameters the mutant strain of A.niger was a fast
growing organism whereas NG-110 had the ability to
hyper produce the citric acid
• The utilisation of cane molasses as a cheap and
abundantly available source was also taken into account.
• Conidia inoculum was carried out with sterilisation with
Monoxal OT solution and clumps were aseptically
separated and then counted with haemocytometer.
17. • The supernatant was diluted to 15%sugar levels
and 2ml of molasses. After series of steps the
solution was used for the estimation of citric acid
and sugar levels.
• Assay method was carried out by DNS and
pyridine acetic an-hydric method.
• In the result it was seen that the rate of citric acid
fermentation by a strain of Aspergillus was 24-
242h. After initial incubation for 24 hours the
citric acid produced was 10.50g/l, increase in
incubation time lead to increase in yield.
• On the basics of sugar the citric acid production
was 60.96% but further increase in incubation
period did not show any enhancement.
18.
19. ARTICLE 3
Citric Acid Production from Non
treated Beet Molasses by a
Novel Aspergillus niger Strain:
Effects of pH, Sugar and
Ingredients
Seda Guc and Osman Erkmen; Department of of
Food Engineering, Faculty of Engineering,
University of Gaziantep, 27310 Gaziantep, Turkey
20. • Effects of factors on the citric acid production from
non-treated beet molasses were studied in
Aspergillus niger OE55. Here Maximum amount of
citric acid (19.13 and 34.62 g/L) was achieved when
the initial pH of fermentation medium was 6.0 from
200 g/L and 150 sugar respectively.
• Citric acid production and biomass formation
continuously increased during fermentation period
in the media.
• A. niger is very sensitive to trace metal ions in the
beet molasses. Despite treatment with chelating
agents (such as sodium or potassium ferro-
cyanide), molasses give low yields of citric acid .
Therefore, beet molasses requires treatment before
use in the production of citric acid. There is a
requirement to find the mutant.
21.
22. • In this study, a novel A. niger OE55 mutant strain has
been tested to able to produce citric acid from non-
treated beet molasses under different fermentation
media. Since, this type of strain necessary to reduce
cost of citric acid production.
• The fermentation media were prepared from non-
treated beet molasses together with different
ingredients and used in shake flask studies. pH of the
fermentation media is adjusted to 6.0.
• Inoculum culture were used to inoculate the
fermentation flasks which were then incubated at 30
± 1°C under shaking conditions at 220 rpm in the
shaker for 8 days. About 10 ml of samples (cultures)
were removed at each sampling time (0, 2, 4, 6 and 8
days of fermentation) under aseptic conditions and
used in analysis.
23. ARTICLE 04
SOME FACTORS AFFECTING CITRIC
ACID PRODUCTION FROM SUGAR
CANE MOLASSSES BY
ASPERGILLUS NIGER
Hauka,F. I. A. ;M. M. A. Ell-Sawah; M. M Kassem
and Sh. M. El-Kady
24. • The production or formation of citric acid is carried out from
molasses by Aspergillus niger in submerged culture.
• The main thing that they focused on the different factors were
affected on the citric acid such as concentration ,volume,
maximum productivity obtained, effect of metal ions
,treatment ,pH, high inoculum size, yield ,etc.
• Citric acid production is one such method that is used for the
food and pharmaceutical industries and in using agricultural
products and their wastes such as molasses and sugar beet
molasses.
• Pre treatment of molasses is carried out in order to eliminate
or remove heavy metals or inhibitory substrate.
• The fermentation method using in Aspergillus niger provides
ease of separation for the product which has been produced by
conventional submerged culture in which biomass or spores
are suspended in medium and can be readily achieved
25. • Incubation period of citric acid production takes place within 6
days and performed under haemocytometer
• The result of the effect of concentration was increased with the
increasing of heavy metals which gives the highest value of citric
acid concentration.
• The pH decreased during fermentation because the total untreated
molasses remained constant and was low in comparison during
fermentation time through which immobilized spores are present.
• The maxim citric acid concentration was obtained after 6 days of
incubation period.
• The sugarcane molasses in Aspergillus niger reached its maximum
without fungal effect and be treated in free environment.
• The biomass of or total yield spores was counted under
haemocytometer.
26. • The objective of our project is to estimate
the yield of citric acid produced by
sugarcane and beet molasses.
• To observe which technique produces
more citric acid , whether it’s solid state
fermentation or shake flask fermentation.
29. SHAKE FLASK
FERMENTATION
1000ML of sterile MRBA broth was taken and spore inoculation was carried
out for A.niger.
It was then incubated at 25-30⁰C for 3 days in a mechanical shaker. And
then estimation was carried out by titration method
The cultured medium was filtered and collected. Pipette out 10ml of
filtrate and add phenolphthalein indicator.
Titrate against 0.1N NaOH until the pale pink colour persists and collect
concordant readings.
Estimation of citric acid was carried out after required calculations.
30. The solid substrate is soaked with water up to 65-70% of water content. After the
removal of excess water, the mass undergoes a steaming process.
Sterile starch paste is inoculated by spreading Aspergillus niger conidia in the
form of aerosol as a liquid conidia suspension on the substrate surface
The pH of the substrate is about 5.5 and incubated at 28-30⁰C .Growth can be
accelerated by adding ᾳ-amylase , although the fungus can hydrolyse starch on its
own too. During citric acid production the pH is dropped due to acid formation.
The solid state process takes about 5 to 8 days at the end of which citric acid is
extracted using hot water. In other cases, mechanical passes are used to produce
more citric acid.
SOLID STATE
FERMENTAION
31. EXPECTED OUTCOME
• Sugarcane molasses will have to yield more citric
acid compared to beet because of its impurities
content being more in beet than in cane.
• Shake flask is considered more feasible to
perform compared to solid state because of easy
inoculation process.
• Solid state still needs new designs and
technologies for developing industrially on large
scale.
• The amount was yield would be directly
proportional to incubation period but only up to
a certain limit after which no changes would be
observed in the yield.
32. CONCLUSION
• Cane and beet molasses are suitable for citric acid
production. However, beet molasses is
preferred due to its lower content of trace metals.
• Generally, cane molasses contains calcium,
magnesium, manganese, iron and zinc, which have a
retarding effect on the synthesis of citric acid.
• But industrially sugarcane molasses are preferred
because of low impurities content compared to beet
molasses.
33. REFERENCES
• Bayraktar, E. and U. Mehmetoglu (2000). Production of citric acid using
immobilized conidia of Aspergillus niger. Appl. Bioch. And Biotechnol. Part A,
Enzyme Engin. and Biotechnol. 87 (2): 117-125.
• Benuzzi, D. A. and R. F. Segovia (1995). Effect of the copper concentration on
citric acid productivity by an Aspergillus niger strain. Appl.Biochem. and
Biotechnol. 61: 393–397.
• Show PL, Oladele KO, Siew QY, Zakry FAA, Lan JCW, et al. (2015) Overview of
citric acid production from Aspergillus niger . Fron Life Sci 8: 271-283.
• Lotfy WA, Ghanem KM, El-Helow ER (2007) Citric acid production by a novel
Aspergillus niger isolate: II. Optimization of process parameters through
statistical experimental designs. Bioresour Technol 98:3470-3477
• Vervack, W., 1973. Analyse des aliments. Methodes courantes d'analyses,
Laboratoire de Biochimie de la Nutrition, Luvain-la Neuve, U.C.I.