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Chemical Contaminants Associated with Palm Wine from Nigeria Are Potential Food Safety Hazards


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Recent analysis of palm wine, a traditional drink fermented mainly by yeasts, revealed the presence of several chemicals that were not products of yeast fermentation. The chemicals included styrene, benzene, trimethyldioxolane, dichloromethane, methylene fluoride, dichloroethanol, benzylisoquinoline and tetraacetyl-d-xylonic nitrile. A review of the concentrations of these compounds in palm wine found that the benzene concentrations in all samples reviewed ranged from 56–343 ppm and were within permissible limits, whereas the styrene values (1505–5614 ppm) in all the palm wine samples evaluated were well over the recommended concentration that is immediately dangerous to life or health. Other chemical compounds evaluated varied according to location or sample source. The concentrations obtained are estimates only and a quantitative study needs to be carried out before the impact of these chemicals on health is evaluated. A search on The PubChem Project, the open chemical database, showed the description, properties and uses of these chemicals. Further searches carried out within other databases like PubMed, Scopus and Google Scholar, using each chemical’s name as a search term, showed possible hazards and adverse health conditions caused by these chemicals, especially styrene, benzene and dichloromethane. The point at which the chemicals are introduced into the drink is still not clear and requires further investigation. The chemicals can be hazardous to humans and there is need to establish and maintain a system that can guarantee permissible levels in the drink. This can be carried out using concentrations of the chemicals that are already known to be immediately dangerous to life or health as a reference point.
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Chemical Contaminants Associated with Palm Wine
from Nigeria Are Potential Food Safety Hazards
Ogueri Nwaiwu 1, * and Martin Itumoh 2
1Research Services, Alpha Altis, Sir Collin Campbell Building, University of Nottingham Innovation Park,
Triumph Road, Nottingham NG7 2TU, UK
2Department of Agribusiness and Management, Faculty of Agriculture, Federal University Ndufu Alike
Ikwo, Ebonyi 480101, Ebonyi State, Nigeria;
*Correspondence:; Tel.: +44-785-317-9327
Academic Editor: Dimitrios Zabaras
Received: 30 November 2016; Accepted: 26 February 2017; Published: 3 March 2017
Recent analysis of palm wine, a traditional drink fermented mainly by yeasts, revealed the
presence of several chemicals that were not products of yeast fermentation. The chemicals included
styrene, benzene, trimethyldioxolane, dichloromethane, methylene fluoride, dichloroethanol,
benzylisoquinoline and tetraacetyl-D-xylonic nitrile. A review of the concentrations of these
compounds in palm wine found that the benzene concentrations in all samples reviewed ranged from
56–343 ppm and were within permissible limits, whereas the styrene values (1505–5614 ppm) in all
the palm wine samples evaluated were well over the recommended concentration that is immediately
dangerous to life or health. Other chemical compounds evaluated varied according to location or
sample source. The concentrations obtained are estimates only and a quantitative study needs to be
carried out before the impact of these chemicals on health is evaluated. A search on The PubChem
Project, the open chemical database, showed the description, properties and uses of these chemicals.
Further searches carried out within other databases like PubMed, Scopus and Google Scholar, using
each chemical’s name as a search term, showed possible hazards and adverse health conditions
caused by these chemicals, especially styrene, benzene and dichloromethane. The point at which
the chemicals are introduced into the drink is still not clear and requires further investigation. The
chemicals can be hazardous to humans and there is need to establish and maintain a system that
can guarantee permissible levels in the drink. This can be carried out using concentrations of the
chemicals that are already known to be immediately dangerous to life or health as a reference point.
Keywords: palm wine; chemicals; contaminant; styrene; benzene; food safety; hazard, plastic
1. Introduction
Palm wine is a traditional drink produced by different types of palm trees and is enjoyed by
many people living in sub-Saharan Africa. Around the world, the beverage is popular and is known
by different names. Increased microbiological studies of the product in the last five years has led to
more information on the diversity of Saccharomyces cerevisiae strains prevalent in the product [
] and
discovery of new microorganisms from the drink [
]. The tapping of the drink from the palm tree
provides a very important economic activity for people living outside of the cities, and the drink plays
an important role in the socio-cultural activities of people in Nigeria, where, in the southeastern region,
it is served in most traditional events. The drink is now beneficial to different groups of people in that
some people in Nigeria who are cutting alcohol consumption resort to freshly tapped product which is
sweet and without much alcohol.
The commercial production of the drink has increased and it is now canned. The drink is commonly
produced in beer like bottles in Nigeria and a good number of retailers sell the product with reused
Beverages 2017,3, 16; doi:10.3390/beverages3010016
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table water plastic bottles with the cap loosely fitted to reduce foaming. The vast production and sale
of the product is not regulated and this makes the drink predisposed to food safety hazards which
could be biological, chemical, physical, allergenic, nutritional or biotechnology-related [
]. It has
been reported that the drink can be contaminated at multiple steps in the production process and
should be regulated for quality control to avoid health risks [
]. In addition, plant material treated
with herbicides and pesticides can be present in the palm wine processing environment, and it is not
uncommon to see producers that use leaves to cover containers containing the drink. Leaves, stem and
bark can also get into the palm wine either when the incision is made to begin the tapping process or
when the sap is flowing into a container. In some palm wine processing environments, insects could
be a source of food safety hazards when they fly into bowls or containers containing the drink.
Food safety hazards [
] occur when food is exposed to hazardous agents and results in
contamination of the food. It may occur through air, soil and water in the environment. Furthermore,
in the food industry, there are various types of chemical hazards and they include mycotoxins, natural
toxins, marine toxins, environmental contaminants, food additives, processing-induced chemicals,
pesticides, agricultural products and veterinary drug residues [
]. Currently, there is no evidence
that hazard analysis and critical control points (HACCP), a systematic preventive approach to food
safety from biological, chemical, and physical hazards, are used during the production of palm wine
among local processors. Many workers [
] have studied the microbial and biochemical constituents
of the drink, especially compounds of microbial fermentation, and they are not currently regarded
as hazards.
There are rarely any reports on the chemical contaminants of the product. The metal concentrations
of 13 elements in the drink have been determined, and it was found that, from the estimated target
hazard, no long life health concerns of metals are associated with the consumption of Raphia palm
wine [
]. The chemical contaminants per se were not analyzed in that study. However, it was found
that the individual and combined metal target hazard quotient values of Raphia palm wine were
higher in other traditional alcoholic drinks. The lack of information on chemical contaminants of
palm wine has created a paucity of information on the properties of non-ethanol and non-microbial
components associated with the drink as well as other food safety hazards linked with unregulated
processing of the beverage.
In a previous study [
], some chemical compounds were not identified as products of yeast
fermentation in palm wine after a search on the yeast metabolome database (YMDB) was carried
out [
], and it was suggested that the contaminants were artifacts from the environment. Irrespective
of how the chemical contamination occurred, the presence of these substances in palm wine is not
desirable. Therefore, the aim of this review was to focus on these chemical contaminants and highlight
safety concerns that should be addressed for the health benefits of palm wine consumers. To this
end, the properties, uses, toxicity, and health issues associated with palm wine chemical contaminants
detected in the previous study were explored in more detail in order to raise more awareness on the
possible hazards that could arise from consumption of the beverage.
2. Methods
The chemical contaminants found in palm wine (Figure 1) are listed in Table 1. In the absence
of actual sources of these contaminants, the hypothetical sources are specified. An investigation [
reported that palm wine obtained from trees of Elaeis sp. and Raphia sp. were purchased (1.5 L
pack size) from six different open markets in southeastern Nigeria. Using a wide range of analytical
techniques, the microbial and chemical contents were determined. In particular, the use of gas
chromatography-mass spectrometry (GC-MS) revealed that all the palm wine samples contained
chemical compounds that are known carcinogens. There is a paucity of data on palm wine contaminants
in literature. However, an earlier study [
] reported some of the compounds listed (Table 1) and it
included styrene and dimethylbenzene. Another investigation reported [
] the presence of phenyl
compounds among other volatiles. A search was conducted within The PubChem Project, the open
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chemical database [
], to establish the description and uses of candidate chemicals (Table 1). The main
reason for including these chemicals in the search was because they are not associated with yeast
fermentation of palm wine. The compound identifier and uses of these chemicals were captured.
1.Styrene750144954299 3132 1938 1867 1505 5614 700PlasticsPlasticcontainer
2.Benzene241332268 173 87121 56343 500SolventBenzoicacid+
3.Trimethyldioxolane1258632811533 789 3560 462 2298 3581 500
4.Dichloromethane6344108168 367 835 151 135 301 2300SolventEnvironment
5.Methylenefluoride634512628482146140 5825
6.Dichloroethanol11718693118 134 158 70390 125 3000
7.Dimethylhydrazine59769264889 9162 7238 352 766 540 50PesticidesEnvironment
8.Dimethylhydrazine1668069673138 210 169 127 53116 66.1
xylonic5415688768132 96118 88152 250
Figure 1.
Representative samples of palm wine bottles sold in Nigeria. The samples in glass bottles
) are now exported around the world. Samples in polyethylene terephthalate bottles (
) with
polystyrene caps are normally found in small retail outlets.
Table 1. Estimated concentrations of chemical contaminants associated with palm wine samples.
Compounds PubChem
Estimated Concentrations 2in Palm Wine (ppm) IDLH 3
(ppm) Uses Possible
S1 S2 S3 S4 S5 S6 S7
1. Styrene 7501
4495 4299 3132 1938 1867 1505 5614
700 Plastics Plastic container
2. Benzene 241 332 268 173 87 121 56 343 500 Solvent Benzoic acid +
Vitamin C
3. Trimethyldioxolane 12586
3281 1533
2298 3581
500 4Solvent Derivative
4. Dichloromethane 6344 108 168 367 835 151 135 301 2300 Solvent Environment
5. Methylene fluoride 6345 126 28 48 21 46 140 58 25 5
6. Dichloroethanol 11718 693 118 134 158 70 390 125 3000 6Solvent Environment
7. Dimethylhydrazine 5976 926
4889 9162 7238
352 766 540 50 Pesticides Environment
8. Dimethylhydrazine 16680696 73 138 210 169 127 53 116 66.1 7
Leaves or tissue
9. Tetraacetyl-D-xylonic 541568 87 68 132 96 118 88 152 250 8Plant part Plant compound
CID = compound identifier; Information sourced from PubChem open chemistry database [
estimated in palm wine from Nwaiwu et al. study [
IDLH = Immediately dangerous to life or health; S = sample.
4IDLH for Dioxane. 5IDLH for Fluorine. 6IDLH for Dichloroethane. 7IDLH for Quinone. 8IDLH for Phenol.
To verify safe levels, another search was performed on the revised list of immediately dangerous
to life or health concentrations (IDLH) of chemicals held by the Center for Diseases Control and
Prevention, United States of America [
]. Where the exact compound of interest was absent on the
list, a closely related compound was highlighted. In the previous work [
], the chemical abundance
was determined by comparing GC-MS peak areas across samples. In this review, we used the peak
areas within samples to estimate the percentage concentration before converting to parts per million
(Table 1) and then compared values obtained with IDLH limits. Further searches were carried out
on other databases like PubMed, Scopus and Google Scholar using each chemical’s name as a search
term. The search strategy employed focused mainly on articles from the last 10 years and only articles
that had information on how these chemicals affect public health were selected. The capacity to cause
harm by the chemicals of interest was noted. Possible hazards from polyethylene terephthalate (PET),
a common retailing container, were highlighted.
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3. Styrene
According to the United States Department of Energy [
], styrene monomer is a colorless oily
liquid, large-volume chemical used in making polyesters, resins, and chemical intermediates with a
global market value of approximately $32.5 billion. Most PET bottles used for retailing palm wine have
a polystyrene cap, which is a safety concern if styrene migrates to the drink. An
in vitro
investigation to evaluate the genotoxicity of styrene oligomers extracted from polystyrene intended for
use in contact with food has been conducted [
], and it was concluded that the risk of the genotoxicity
of styrene oligomers migrating from polystyrene food packaging into food is likely very low.
Styrene Exposure
In all samples, the estimated styrene concentration was over the concentration immediately
dangerous to life or health (Table 1). Although styrene exposure will occur mainly to those that are
involved in the manufacturing of plastics and composites, the detection of high concentrations of
the monomer in palm wine suggests that there is some form of exposure to palm wine consumers.
It also indicates that not all containers used for the drink are food grade. Adverse properties of
styrene exposure have been reported and styrene has been linked to eosinophilic bronchitis [
] and
transient bilateral vestibular dysfunction [
]. It has also been reported that styrene has an effect on
hearing loss [
] and may affect neurological behavior [
]. The effect of occupational exposure
to styrene on frequencies of chromosomal aberrations and binucleated cells with micronuclei and on
single-strand break levels in peripheral blood lymphocytes has also been studied in styrene-exposed
lamination workers [
]. It was found that positive correlation between exposure parameters and
DNA repair rates suggests that particular DNA repair pathways may be affected by styrene exposure.
4. Benzene
4.1. Benzene as a Carcinogen
Even though all samples evaluated were within permissible limits (Table 1), the exact route of
entry of benzene into palm wine needs to be established due to the carcinogenic nature of the drink.
The compound is a known human carcinogen for all routes of exposure and is a widely used chemical
formed from both natural processes and human activities [
]. It is also believed to rank in the top
20 chemicals for production volume. Furthermore, industries use benzene to make other chemicals
that are used to make plastics, resins, and nylon and other synthetic fibers. Benzene is found in the air
from emissions from burning coal and oil, gasoline service stations, cigarette smoke and motor vehicle
exhaust. Inhalation exposure of humans to benzene may cause drowsiness, dizziness, headaches,
as well as eye, skin, respiratory tract irritation, and unconsciousness [
]. The specific hematologic
malignancies that benzene is associated have been outlined and they include acute myeloid leukemia,
myelodysplastic syndrome, acute lymphoblastic leukemia and chronic myeloid leukemia [27].
4.2. Benzene Formation in Beverages
It has been previously reported [
] that the reaction of benzoic acid and ascorbic acid (vitamin C)
can induce benzene formation in vitamin C drinks. There is ascorbic acid inherent in fresh palm
wine [
] and benzoic acid from plant material [
] can get into the drink at any point in the production
process. This provides an opportunity for both compounds to combine and form benzene, which could
be hazardous to health. The actual source of benzene in palm wine is still unclear and needs to be
investigated further.
A survey of over 100 soft drinks and other beverage samples with a focus on soft drinks that
contain both benzoate salts and ascorbic or erythorbic acid has been carried out [
] in the United States
of America. It was found that four beverage products contained benzene levels above the 5 ppb quality
standard for drinking water. It was also reported that these products with high benzene content were
reformulated by the manufacturers, and, following a re-test, samples of these reformulated products
Beverages 2017,3, 16 5 of 12
showed that benzene levels were less than 1 ppb. The level of benzene in the bottled (Figure 1) and
canned products is important because benzoates are likely to be used as preservatives. Corrective
actions should be taken if the levels are found to be above acceptable thresholds.
5. Trimethyldioxolane
It is known that dioxolanes are highly flammable liquid and vapor that can easily be prepared
from carbonyl compounds with 1,3-propanediol or 1,2-ethanediol in the presence of a Brönsted or
a Lewis acid catalyst [
]. It is not clear if its occurrence in palm wine is through reaction between
other compounds present in the palm wine or reaction between extraneous materials. However, the
properties of the compound indicate that it should be avoided. The hazard warnings for the chemical
states that it can cause harm if swallowed and it is suspected of causing genetic defects and damage of
an unborn child [
]. Apart from one sample that was within permissible limits (Table 1), all the other
samples were over the recommended IDLH limit for dioxanes. The key to reduction of this compound
in the drink may be to avoid the entry of extraneous materials.
6. Dichloro Methane
According to Gribble et al. [
], dichloro methane or methylene chloride is among organohalogen
compounds that were once dismissed as accidents of nature or isolation artifacts and natural sources
include oceanic sources, macroalgae or wetlands. In addition, the majority of dichloromethane in the
environment is the result of industrial emissions, and its occurrence in palm wine could be from plant
material or environmental pollution. Even though the compound is reasonably implicated as a human
carcinogen [
], it has many industrial uses that include insect sprays, postharvest fumigant for grains,
manufacture of drugs, and decaffeination of coffee [
]. The compound can be dangerous if the lethal
dose is reached as exemplified by the reported death of 14 workers who used the product to refinish
bath tubs [
]. The estimated concentration levels seen in all palm wine samples analyzed is far less
than the dangerous concentration limit (Table 1).
7. Methylene Fluoride
Methylene fluoride or difluoromethane (HFC32) is a colorless hydrofluorocarbon gas that is
slightly toxic in rats [
]. It is based on methane, the most abundant hydrocarbon in the atmosphere,
and it is an important greenhouse gas except that two of the four hydrogen atoms have been replaced
by fluorine atoms [
]. In the YMDB [
], fluoride (YMDB 01518) is listed as a product of yeast
anaerobic fermentation of Saccharomyces cerevisiae. Fluoride is a ubiquitous environmental toxin that
all biological species must cope with, and protection is achieved through fluoride export proteins that
protect organisms from fluoride toxicity by removing it from the cell [
]. Therefore, one way of its
occurrence in palm wine may be through the reaction of methane in the atmosphere and fluoride, a
product of anaerobic fermentation by yeasts.
All samples analyzed were above the IDLH limit for fluorine apart from one sample (Table 1).
Environmental contamination appears to be the route of entry into palm wine. Screening the process
environment for fluorides may prevent contamination. According to Tsai et al. [
], hydrofluorocarbons
(HFCs) are now used as replacements for chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons
(HCFCs) that cause significantly stratospheric ozone depletion and global warming. In addition,
they are used commercially in cleaning solvents in the electronic components, blowing agent in the
foamed plastics, and refrigerant in the air conditioning units and refrigerators. It has been reported
that high concentrations [
] may cause asphyxia from lack of oxygen or act as a narcotic causing
central nervous system depression. The report added that overexposure can cause dizziness, headache,
tiredness, nausea, unconsciousness, and cessation of breathing.
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8. Dichloroethanol
Dichloroethanol is regarded as a biohazard and it is flammable corrosive and harmful [
In rats, it is formed during the metabolism of an air borne chemical 1,2-dichloroethene by the hepatic
mixed function oxidase system [
]. In this reaction, cis and trans isomers are metabolized to an
epoxide and the aldehyde formed from the cis isomer yields dichloroethanol. It is also a metabolite of
trichlorfon, an insecticide used to control a variety of insects on an extensive range of crops [
]. It is
possible that it is an intermediate product from other reactions in the palm wine drink and not a direct
contaminant. The contamination levels varied in different samples and were all within permissible
limits for dichloroethane (Table 1).
9. Dimethylhydrazine
The estimated concentrations of dimethyl hydrazine found in all samples were far above
the recommended limits (Table 1). This suggests a serious issue of environmental contamination.
The compound is currently used in many cancer studies [
] because it is a known carcinogen that
can cause sporadic forms of colon carcinoma in rats resulting in a reproducible experimental models
for pre-clinical screening of test compounds based on its metabolism [
]. It has been reported that the
metabolism of dimethyl hydrazine leads to the formation of azoxymethane methylazoxymethanol and
methyl diazonium ions, which can cause alkylation of the DNA in the colon mucosa [
]. Dimethyl
hydrazine is associated with rocket fuels, cigarette smoke, tobacco products and plant pesticides [
Using a theoretical approach, Carlsen et al. [
] carried out a preliminary assessment of the potential
environmental and human health impact of unsymmetrical dimethylhydrazine as a result of space
activities. It was revealed that inside the fall region of burned-out rocket stages constitute a significant
threat to both environmental and human health, the latter as a result of the carcinogenic, mutagenic,
convulsant, teratogenic and embryotoxic characteristics of dimethylhydrazine.
Apart from rocket fuel, other aforementioned substances in dimethyl hydrazine can occur in palm
wine processing environment. The impact from rockets may not be a concern for now considering that
Nigeria’s space technology is still developing. However, smoking, use of tobacco and application of
plant pesticides should be avoided in the palm wine processing environment.
10. 3-Methyl-6,7-benzylisoquinoline
Only one sample out of the seven samples analyzed was within the recommended limit for
quinone (Table 1). Avoiding extraneous leaves making contact with the drink may eliminate the
problem. According to Galanie and Smolke [
], the compound benzylisoquinoline is a class l-tyrosine
derived plant alkaloids. Benzylisoquinoline alkaloids have a pharmaceutical value and they are large
and structurally diverse family of plant secondary metabolites [
] that includes the opiates such as
morphine [
]. Using synthetic chemistry and biology approaches, a strain of Saccharomyces cerevisiae,
the dominant yeast species found in palm wine has been engineered to synthesize the key intermediate
reticuline and other metabolites from benzylisoquinoline [52].
Considering that Benzylisoquinoline alkaloids are plant metabolites that are present in plant
cells [
], its presence in the palm wine may be from the palm tree from which the palm wine was
obtained. More knowledge may be gained if an investigation is carried out to establish if Saccharomyces
cerevisiae from palm wine can naturally synthesize the compound. It has been reported that many plant
species are currently recognized as toxic for both animals and humans, and some of them are known
to cause their toxic effects due to their alkaloid content [
]. The report pointed out that the alkaloid
content may include pyrrolizidine alkaloids and neurotoxins. Diseases associated with alkaloids
from plant seeds have been reported [
] and so contact of the palm wine with plant seeds should be
avoided during the palm wine production process.
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11. Tetraacetyl-D-xylonic Nitrile
The compound tetraacetyl-d-xylonic nitrile has been found in the ethanolic leaf extract of
Croton bonplandianum [
] and has been associated with metabolism of Aspergillus niger after methanolic
extracts were analyzed with gas chromatography-mass spectrometry [
]. It is also a volatile metabolite
of the endophytic fungi Fusarium sp. [
] and has been listed as one of the nitrogenous products
from fermented soy bean meal with Trichoderma sp. [
]. Furthermore, it has been found in trace
amounts when the chemical composition of essential oils from aerial parts of Sisymbrium irio from
Jordan was determined [
]. It is evident that this compound is very present in the environment and
appears harmless in small amounts. However, it has been implicated in the
in vitro
cytotoxicity of
Indian bee propolis on cancer cell lines [
]. As the compound is associated with several plants and
fungal organisms, it could have entered the palm wine drink at any point in the production process.
The concentration (Table 1) estimated in all of the palm wine samples is below the limit for phenols
found in most plants.
12. Physical and Other Chemical Contaminants
Chemical contaminants in food [
] can come from pesticides and veterinary medicines used in
farming, acrylamides used in processing, natural aflatoxin that occur during storage and pollutants
such as dioxins in the environment. Physical and other contaminants can get into the drink through the
water used for dilution. A frequent complaint by palm wine consumers is adulteration of the product
with water to boost product volume followed by addition of artificial sweeteners [
]. This is why
undiluted palm saps are generally more expensive than diluted ones. Due to no portable water at some
palm wine processing centers in Africa, water may be sourced from nearby open wells and streams or
transported with plastic containers, and, if the container has been used to store other materials, there
is the possibility of introduction of extraneous materials into the drink. The extraneous items may
include plant leaves, twigs and dead insects.
Ukhun et al. [
] compared the heavy metal profile of fresh palm wine and those of seven brands
of bottled palm wine using atomic absorption spectroscopy in Benin City, Nigeria and found that the
bottled samples contained toxic levels of either lead or cadmium. Both metals were detected in fresh
palm wine and it was suggested that most of the metals detected were as a result of dilution with
contaminated water. The suspicion that the water used for bottling was from questionable sources was
strong, given that around the time the study was carried out, there were reports that the ground water
in Benin City was reported to be contaminated with unacceptable levels of lead, cadmium, chromium
and zinc [64].
13. Toxicity Concerns with Use of Plastic Containers
13.1. Plastic Degradation
Finally, there are concerns about the use of PET and other plastic containers as the main storage vessels
of palm wine from the tapping process up until consumption because some of the aforementioned
chemicals may be constituents of a PET or plastic container used in the production process. In Europe,
European regulation No. 10/2011 [
] ensures the safety of plastic materials in contact with foodstuffs.
This regulation has a list of substances that are authorized for use in plastic materials and some
compounds are subject to restrictions according to their toxicological data. Such regulations can be
adopted to prevent plastic hazardous material from getting into the palm wine drink.
Plastic containers are used virtually in all processing steps. Even the palm wine calabash that
is popular in Nigerian folklore has been replaced by plastic containers. In a study by Obahiagbon
and Oviasogie [
], the initial palm wine exudate was collected with a plastic funnel and receptacle.
An investigation [
] with scanning electron microscopy and energy dispersive X-ray spectroscopy to
evaluate the interactions of palm wine with the surface of its PET containers did not find any pitting
or extensive corrosion. However, the PET container that was used for palm wine storage showed
Beverages 2017,3, 16 8 of 12
the presence of chlorine, whereas no chlorine was observed for the control sample that contained
water. It was suggested that, at some point in the palm wine supply chain, a polyvinyl chloride plastic
container may have been used to store the product.
Polyvinyl containers are degradable under high temperature. McNeill et al. [
] carried out a
thermal degradation study and found that analysis of the liquid fraction collected during pyrolysis
included hydrogen chloride, chlorine, tar, and benzene. There are other concerns that reused chemical
plastic containers may still contain traces of chemicals, which may react with palm wine and cause
corrosion of the plastic container. Although it is generally believed that PET bottles take a long time to
degrade, the degradation of PET bottles has been successfully achieved in 2 h using hydrotalcite as
catalyst and ethylene glycol as solvent [
]. Therefore, the various types of plastic used in the storage
of the product should be evaluated to establish if there are reactions with the container.
13.2. Other Plastic Constituents
Bach et al. [
] carried out a comprehensive literature review which showed that contradictory
results for chemical migration in PET-bottled water have been reported, and the differences can be
explained by the wide variety of analytical methods, bioassays and exposure conditions employed.
It was reported that analysis of PET reveals some non-intentionally added substances produced by
initial reactants and additives. In addition, plasticizers, formaldehyde, acetaldehyde and antimony
are related to migration from PET into bottled water, but the origin of these compounds has not been
clearly established. The compounds could be from PET containers, cap-sealing resins, background
contamination, water processing steps, and recycled PET bottles. The effect of sunlight exposure
on chemical migration into PET-bottled waters has been studied [
]. Bottled waters were exposed
to natural sunlight for 2–10 days, and it was found that migration was dependent on the type of
water. PET-bottled water extracts did not induce any toxic effects, cyto-genotoxicity, estrogenic,
or anti-androgenic activity in vitro at relevant consumer-exposure levels.
14. Conclusions
From the qualities of the chemicals outlined above, it is evident that the chemicals are potentially
hazardous. It will be beneficial to public health to determine if concentrations found in palm wine
are dramatically increased when compared to other food-associated samples. The concentrations of
the chemical compounds in palm wine given are estimates only and a quantitative study needs to
be carried out with the relevant chemical standard before the impact of these chemicals on health is
evaluated. Even though private processing of the product may be difficult to monitor, unregulated
commercial processing should be discouraged and only those who have been sensitized on the
microbiological, physical and chemical hazards should be allowed to process and sell the product to
the public. In addition, use of only food grade plastics, especially for bulk transportation of palm wine,
should be allowed. Agricultural extension and health officers would need to sensitize processors to
avoid reuse of plastic containers that have been used for storage of any toxic chemicals. A detailed
hazard analysis that covers palm wine processing and the whole palm wine supply chain will be
beneficial to public health.
The work was supported by the International Development Fund grant to O.N. from Society
for General Microbiology (now Microbiology Society) UK. Grant No IDF 2012/12/3.
Author Contributions: O.N. conceived the paper; and O.N. and M.I. contributed to the paper.
Conflicts of Interest: The authors declare no conflict of interest.
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... Palm wine is obtained from the fermentation of sap obtained from palm tree species such as Elaeis guineensis, Raphia hookeri, Borassus aethiopum, and Borassus akeassii. The production of ethanol, lactic acid and acetic acids by yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB) are the most significant activities contributing to the distinctive organoleptic characteristics and stability of the product (Amoa-Awua, Ngunjiri, et al., 2007;Karamoko et al., 2012;Nwaiwu & Itumoh, 2017). The gradual accumulation of ethanol at the early stages of fermentation correlates with the increase in the AAB population, as AAB can use ethanol as a carbon source (Amoa-Awua, Ngunjiri, et al., 2007). ...
... cereals (Angelov et al., 2017;Oguntoyinbo et al., 2011) and dairy products (Akabanda et al., 2013). The extensive species diversity revealed by the use of genotyping techniques has been reported for other IFFs (Achi, 2005;Aderigbigbe et al., 2011;Nwaiwu & Itumoh, 2017;Ouoba et al., 2012) and has also uncovered new microbial species (Ouoba et al., 2015, a, b). More recently, culture-independent methods such as PCR-DGGE and next-generation sequencing techniques are used to investigate the metagenomics associated with IFF production (Cason et al., 2020;Djeni et al., 2020;Walsh et al., 2017). ...
... For example, the production of the widely consumed sorghum-based fermented beer umqombothi has been industrialised in South Africa. Cerealbased porridges ogi and uji, and the alcoholic beverage palm wine are also now produced commercially (Adebo, 2020;Nwaiwu & Itumoh, 2017). Significant advances have been made in identifying dominant strains in IFFs and characterising technological aspects which make them suitable for use in controlled fermentations (Aderigbigbe et al., 2011;Ahaotu et al., 2013;Aka et al., 2020;Houngbédji et al., 2018;Moodley et al., 2019;Oguntoyinbo & Narbad, 2015;Sawadogo-Lingani et al., 2007). ...
Indigenous fermented foods (IFFs) have a long history in Africa and are embedded in cultural norms and practices. Typically, these foods are produced at small or household scale using indigenous processing technologies. In addition, limited knowledge of good manufacturing and handling practices can lead to production under unhygienic conditions. This results in variations in the quality and safety attributes of IFFs, as spoilage and pathogenic bacteria can be introduced at any stage of the value chain. These foods have an important role in the African diet and can contribute to food security by increasing the availability of cheap, nutritious food and supporting livelihoods. However, the presence of foodborne pathogens and antibiotic-resistant bacteria in IFFs may constitute a health risk to consumers. Therefore, this review presents an overview of the microorganisms associated with IFFs from Africa, focusing on microbial food safety hazards. African indigenous fermented foods offer a vast genetic potential of undiscovered strains that possess valuable technical characteristics. However, IFFs may also serve as vehicles of pathogenic and antibiotic-resistant bacteria and genetic determinants. Significant research and data gaps exist regarding the microbiological safety of these food products, which warrant urgent attention. We propose practical solutions for improving the safety of African IFFs requiring action and collaboration from all stakeholders, including researchers, producers, governmental regulatory bodies, and consumers.
... Many developing countries, especially Africa, rely on indigenous fermented foods , hence a closer study of the fermentation process and the microorganisms involved may help reformulate the food. There are food safety concerns, especially with microorganisms and chemical contaminants (Nwaiwu & Itumoh, 2017), and these need to be taken into consideration. There is a possibility that other nutrients may be lost if the natural structure of food material is tampered with. ...
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Food reformulation, the process of redesigning processed food products to make them healthier, is considered a crucial step in the fight against noncommunicable diseases. The reasons for reformulating food vary, with a common focus on reducing the levels of harmful substances, such as fats, sugars, and salts. Although this topic is broad, this review aims to shed light on the current challenges faced in the reformulation of food and to explore different approaches that can be taken to overcome these challenges. The review highlights the perception of consumer risk, the reasons for reformulating food, and the challenges involved. The review also emphasizes the importance of fortifying artisanal food processing and modifying microbial fermentation in order to meet the nutrient requirements of people in developing countries. The literature suggests that while the traditional reductionist approach remains relevant and yields quicker results, the food matrix approach, which involves engineering food microstructure, is a more complex process that may take longer to implement in developing economies. The findings of the review indicate that food reformulation policies are more likely to succeed if the private sector collaborates with or responds to the government regulatory process, and further research is conducted to establish newly developed reformulation concepts from different countries. In conclusion, food reformulation holds great promise in reducing the burden of noncommunicable diseases and improving the health of people around the world. Redeveloping an existing processed food product to make it healthier is the focus of food reformulation. However, the approaches for food reformulation are diverse, and there is a consensus that the main concerns are fats, sugars, and salts. Food reformulation policy would certainly succeed if the private sector works in tandem with and/or responds to government pressure.
... If the chemical contaminants concerns found in another traditional drink [169] are applicable and addressed for the Kunu drink, then the prospects of improving the profile of the drink is very high. Apart from the dietary benefits, there would be increased generation of waste which can be upcycled or valorised [170]. ...
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Kunu is a fermented non-alcoholic beverage consumed all over Nigeria. The drink is served as an alternative to alcohol due to its perceived extreme nourishing and therapeutic properties. Varieties of this beverage are determined mostly by the type of grain, the supplements, sensory additives used, and the process employed during its production. Dietary quality is paramount in nutritional well-being and a key factor in human overall health development. The nutritional quality of grains utilised for Kunu production makes the drink more appealing to a large growing population when compared to some other drinks. Some use Kunu drink as an infant weaning drink, thus serving as a priming beverage for infants due to its rich probiotic and nutritional properties. However, this beverage’s short shelf-life has limited its production scale. This review therefore elaborates succinctly on the diverse therapeutic nutritional properties of the Kunu beverage and the effect of additives and fermentation on the microbial dynamics during Kunu production, as well as the prospect of Kunu in diet diversification and priming for weaning infants.
... Nevertheless, proper hygiene measures are needed to create awareness of quality control and hygienic practices in producing quality palm oil. Speculatively, the potentially harmful effects of unrefined traditionally processed palm oil can outweigh its nutritional benefits due to the presence of some components, which contribute to the numerous chemical reactions in the degradation of such product [13]. In Nigeria, purchased or processed palm oil is usually stored in big containers for several months or years for economic reasons. ...
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This study was designed to evaluate the microbiological, physical, and chemical effects of ginger extracts and sterilization on palm oil samples sourced from markets in the Southern Senatorial District of Ondo State, Nigeria. Water and ethanol ginger extracts were used for palm oil treatment. Microbial isolation was performed by serial dilution and pour plating techniques. Pure isolates were obtained by repeated streaking. Isolates were identified based on cultural, biochemical, and morphological characterization. Biochemical parameters, such as free fatty acid, peroxide value, moisture content, impurity level, and iodine value, were determined. Sterilized palm oil had no microbial growth with low values in all evaluated parameters. The bacterial genera isolated from the palm oil samples included Pseudomonas, Bacillus, Enterococcus, Staphylococcus, and Micrococcus. The discovered fungal species included Aspergillus niger, A. flavus, Cochliobolus sp., Penicillium citrinum, P. italicum, P. chrysogenum, Geotrichum clavatum, Mucor spp., Chrysosporium tropicum, Fusarium solani, Microsporum canis, and Meyerozyma guilliermondii. These microorganisms indicated the unhygienic condition of palm oil production chain from processing to packaging and market display. Both ginger extracts and sterilization were efficient in combating oxidative rancidity of palm oil and controlling microbial growth that might alter oil quality. Therefore, adequate quality control measures of palm oil during processing and marketing and treatments will help to reduce post-production contamination and deterioration under storage conditions.
... The nitrile tetraacetyl-d-xylonic is a component found within glucosinolates [46]. This molecule was detected in the alcoholic extract obtained from Croton bonplandianum leaves and was associated with the metabolism of Aspergillus niger [47]. Additionally, the authors state that this molecule is a volatile metabolite that can be extracted from endophytic fungi Fusarium spp. ...
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The high consumption of energy, mainly in the automotive sector, is supplied by fossil fuels, which, when combusted, generate polluting gases leading to the great problem of climate change. This has led society to seek alternatives. Bioethanol is a biofuel that can be obtained from the fermentation of different raw materials rich in sucrose such as sugarcane, which can be mixed with gasoline and used to reduce polluting emissions. The following investigation focused on studying the efficiency of three selected native yeasts in the fermentation of black sugarcane POJ 27-14 variety juice to produce bioethanol and other byproducts of biotechnological interest. A comparison between the size of the inoculum of three selected native yeasts (Lev6, Lev9, and Lev30) and two reference commercial controls in the fermentation process was performed. The phylogenetic classification was carried out based on the analysis of the internal transcribed spacer 1 sequence, 5.8S ribosomal RNA, and internal transcribed spacer 2. Lev6 and Lev30 were classified as Saccharomyces cerevisiae, while Lev9 was Candida intermedia, with 99% nucleotide sequence identity. The results showed that the optimal growth temperature was 30 °C with constant agitation (200 rpm) for biomass production. The Lev30 strain presented the highest yield in the production of biomass from sugarcane juice fermentation, while the Lev6 strain presented the highest yield in ethanol production. Additionally, among native yeasts, Lev6 registered the highest ethanol concentration (Q) and volumetric productivity (Qp) values of 0.61 (g/L/h) and 43.92 g/L, respectively, which were comparable with the control yeasts. The gas chromatography coupled to mass spectrometry (GC-MS) indicated the presence of ethanol in all samples (98% to 99% relative percentages) along with some therapeutic substances such as (2-aziridinylethyl) amine and tetraacetyl-d-xylonic nitrile with greater efficiency than commercial controls from the alcoholic fermentation of black sugarcane juice.
... Some commonly consumed fermented foods include miso, soy paste, natto, and vinegar from East and Southeast Asia and yogurt, cheese, and kefir from Europe and America [6][7][8]. Other traditionally fermented foods include pickled fruit and vegetables and fermented beverages (e.g., beer, wine, and tea) from cereals and plants [9,10]. ...
Full-text available
Fermentation is an important process that can provide new flavors and nutritional and functional foods, to deal with changing consumer preferences. Fermented foods have complex chemical components that can modulate unique qualitative properties. Consequently, monitoring the small molecular metabolites in fermented food is critical to clarify its qualitative properties and help deliver personalized nutrition. In recent years, the application of metabolomics to nutrition research of fermented foods has expanded. In this review, we examine the application of metabolomics technologies in food, with a primary focus on the different analytical approaches suitable for food metabolomics and discuss the advantages and disadvantages of these approaches. In addition, we summarize emerging studies applying metabolomics in the comprehensive analysis of the flavor, nutrition, function, and safety of fermented foods, as well as emphasize the applicability of metabolomics in characterizing the qualitative properties of fermented foods.
... A starting point may be for the government to show more regulatory oversight. There is a consensus that regulatory oversight and better relationships with food producers could improve the current food safety deficiencies in Nigeria [86]. The government should constantly review food safety elements such as leadership, communication, risk perception, self-commitment, and management support. ...
Full-text available
As a developing nation and the most populous nation in Africa, Nigeria has enormous challenges connected with food safety culture. To produce and provide safe, secure and nutritious food, consumers and food businesses must abide by a set of shared values known as food safety culture. In Nigeria, food safety culture is a complex subject due to Nigeria’s heterogeneous and diverse nature, as demonstrated by its over 250 ethnic groups. As Nigeria becomes more urbanized and incomes continue to fluctuate at robust rates, few Nigerians are conscious of food safety issues. In addition, oversight from government regulators around food safety require improvement. Public engagement in food safety issues has not witnessed a promising trajectory in recent years. In this article, we provide a review of the food safety culture in Nigeria and its role and influence on various cases of food safety issues in Nigeria. Of interest to this paper are studies exploring consumer and food handler perceptions and behavior regarding food safety. In addition, keen attention is devoted to areas that are in need of additional research to help address practical and on-the-ground challenges associated with Nigeria’s food safety practices. This article suggests that improving food safety culture in Nigeria requires both applying the best management and communication approaches in different regions and understanding the local food safety practices.
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Background Alcohol consumption and tobacco exposure during pregnancy are hazardous behaviours which are increasing significantly in low and middle-income countries, including sub-Saharan Africa. However, they have received little attention in Nigeria’s maternal health research and services. The prevalence, pattern and predictors of alcohol consumption and tobacco exposure among pregnant women in Ibadan, Nigeria, were investigated. Methods This is a part of a prospective cohort study among pregnant women in Ibadan, Nigeria (Ibadan Pregnancy Cohort Study (IbPCS), which investigated the associations between maternal obesity, lifestyle characteristics and perinatal outcomes in Ibadan. Alcohol consumption and tobacco exposure of 1745 pregnant women were assessed during enrollment by self-reports using an interviewer-administered questionnaire. Bivariate and multiple logistic regression analyses examined the associations at a 5% level of statistical significance. Results The prevalence of pre-pregnancy alcohol consumption and alcohol consumption during pregnancy were 551 (31.7%) and 222 (12.7%), respectively, i.e. (one in every eight pregnancies is exposed to alcohol). Palm wine (52%) and beer (12%) were the most common alcohol consumed among pregnant women. The predictors of alcohol consumption during were pre-pregnancy alcohol use [AOR = 10.72, 95% CI: 6.88–16.70) and religion i.e. Muslims were less likely to consume alcohol during pregnancy compared to Christians: [AOR = 0.60, 95% CI: 0.40–0.92). The prevalence of tobacco exposure in the index pregnancy was 64 (3.7%), i.e. one in every 27 pregnancies is exposed to tobacco. In contrast, cigarette smoking, second-hand smoke and smokeless tobacco were 0.4, 1.7 and 1.8%, respectively. Pre-pregnancy cigarette smoking was reported by 33(1.9%) and was the most significant predictor [AOR = 12.95; 95% CI: 4.93, 34.03) of tobacco exposure during pregnancy in our study population. Conclusions Alcohol consumption and tobacco exposure are not uncommon and have been an ongoing but neglected threat to maternal and child health in Nigeria. Alcohol and tobacco control policy and programmes to prevent the use among pregnant and reproductive-age women in Nigeria should be implemented primarily during antenatal care.
Technical Report
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The reference to palm wine as a drink with many functionalities has increased over the years. However, few empirical tests have been carried out on humans to substantiate the claims. This perspective looks at the biochemical and microbiological reports on palm wine to highlight the constituents that are associated with functional beverages. Based on the constituents of the drink, it may qualify as a multifunctional beverage because several investigators have demonstrated disease risk reduction, improved nutrition and health outcomes in many studies, albeit in rats rather than humans. The constituents found in functional beverages are present in the drink. However, when assessed under European Union regulations, fermented palm wine (from 3% alcohol) cannot be regarded as a functional beverage because beverages that contain over 1.2% alcohol cannot be approved for any claim on health or nutritional benefit. The fresh sap with much lower alcohol may be suitable after it is refined and subjected to scientific examination to determine quantities of the drink that can confer health benefits on humans.
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Background: Colon cancer (CC) is the third commonly diagnosed cancer and the second leading cause of mortality in the US when compared to India where prevalence is less. Possible reason could be the vegetarian diet comprising spices used in curry powders. Researchers believe that 70% of the cases are associated with diet. Spices have inherited a rich tradition for their flavor and medicinal properties. Researchers have been oriented towards spices present in food items for their antitumorigenic properties. Objective: We investigated the effects of sambar as a preventive measure for 1,2-dimethyl hydrazine (DMH)-induced CC in Wistar albino rats. Materials and Methods: The animals were divided into three groups (n = 6) namely control, DMH, and sambar. At the end of the experimental period, the animals were killed using anesthesia and the colons and livers were examined. Results: All the treatment groups exhibited a significant change in the number of aberrant crypt foci (ACF). Sambar group showed a significant change in the colonic GSH when compared to both normal and DMH groups. A significant reduction in the liver GSH was noted in the sambar group. Only sambar group showed a significant change in the liver catalase levels when compared to DMH. There was a significant reduction in the colonic nitrite in the sambar-treated group; 2.94 ± 0.29 when compared to DMH control at 8.09 ± 1.32. On the contrary, a significant rise in the liver nitrite levels was observed in the sambar-treated rats. Conclusion: Sambar may prevent the risk of CC when consumed in dietary proportions. Abbreviations used: ACF: aberrant crypt foci, CC: colon cancer, DMH: 1,2-dimethyl hydrazine, GSH: glutathione, IL-6: Interleukin-6, TNF-α: Tumor necrosis factor-alpha.
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Raffia wine is a traditional alcoholic beverage produced in several African countries where it plays a significant role in traditional customs and population diet. Alcoholic fermentation of this beverage is ensured by a complex natural yeast flora which plays a decisive role in the quality of the final product. This present study aims to evaluate the distribution and the diversity of the yeast strains isolated in raffia wine from four sampling areas (Abengourou, Alépé, Grand-Lahou and Adzopé) in Côte d’Ivoire. Based on the D1/D2 domain of the LSU rDNA sequence analysis, nine species belonging to six genera were distinguished. With a percentage of 69.5 % out of 171 yeast isolates, Saccharomyces cerevisiae was the predominant species in the raffia wine, followed by Kodamaea ohmeri (20.4 %). The other species isolated were Candida haemulonii (4.1 %), Candida phangngensis (1.8 %), Pichia kudriavzevii (1.2 %), Hanseniaspora jakobsenii (1.2 %), Candida silvae (0.6 %), Hanseniaspora guilliermondii (0.6 %) and Meyerozyma caribbica (0.6 %). The molecular characterization of S. cerevisiae isolates at the strain level using the PCR-interdelta method revealed the presence of 21 profiles (named I to XXI) within 115 isolates. Only four profiles (I, III, V and XI) were shared by the four areas under study. Phenotypic characterization of K. ohmeri strains showed two subgroups for sugar fermentation and no diversity for the nitrogen compound assimilations and the growth at different temperatures.
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The effects of variety and tapping length on several physical, biochemical, nutritional and micro-biological parameters (viscosity, pH, Total Titratable Acidity (TTA), fermenting microorganisms, contaminants) of palm wine extracted from two varieties of palm oil tree (Dura and Tenera) were studied. Each variety presented its own palm wine specific characteristics regarding the chosen parameters. Microbiological and biochemical contents of palm wine were determined during the tapping of Dura and Tenera felled oil palm trees for 4 weeks. Some differences in chemical compositions between fresh palm wine samples of two palm trees varieties were observed. The exudates obtained during the first day of tapping of Dura palm wine were very sugary, less sour and did not contain substantial concentrations of alcohol but the highest loads of microorganisms were observed in Tenera palm wine. Throughout the tapping of palm wine, yeasts and lactic acid bacteria population changed with undoubtedly influence on the palm wine quality.
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The aim of this study was to investigate the efficacy of a Berberis integerrima hydroalcoholic extract as a chemotherapeutic agent in colon carcinogenesis in the rat induced by 1,2-dimethyl hydrazine (DMH). Male Wistar rats were divided into five groups: a negative control group without DMH treatment; a control group injected DMH (20 mg/kg b.w); two groups receiving B. integerrima extract (50 and 100 mg/kg b.w), concomitant with injected DMH, as chemotherapeutic groups; a positive control group receiving 5-fluorouracil (5-FU) along with DMH. The effects of the extracts were determined by assessment of hepatic malondialdehyde (MDA), glutathione (GSH), ferric reducing ability of plasma (FRAP), and the activities of hepatic glutathione S-transferase and cytochrome P450 (GST and CYP450). Additionally, colon tissues were assessed for colonic β-catenin and histopathological analysis. In DMH-treated rats, the extracts partially normalized the levels of FRAP, CYP450, β-catenin, and GST. Likewise, formation of aberrant crypt foci (ACF) in colon tissue of DMH-treated was reduced by the extracts. Thus, the extracts possess chemotherapeutic activity against colon carcinogenesis.
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A preliminary evaluation of yeast fermented palm wine sourced from Imo State in Nigeria was carried out to establish compounds that contribute to the distinct flavor of the beverage and to determine if the product abundance is affected when the drink is supplemented with Sacoglottis gabonensis. Palm wine samples from two different trees Elaeis sp. and Raphia sp. (pH less than 5) that contain Saccharomyces cerevisiae and other yeast species identified by sequencing the D1/D2 domain of the 26S rRNA genes were used. Evaluation was carried out using high performance liquid chromatography (HPLC), atmospheric pressure chemical ionization-mass spectrometry (APCI-MS) and gas chromatography-mass spectrometry (GC-MS). Samples contained 5.9–11.6, 2.2–7.1, 4.2–43.0, and 4.4–43.7 g/L of acetic acid, lactic acid, ethanol and glucose, respectively. Ethyl acetate, acetic acid and ethanol had the most aroma intensity and an assessment on the yeast metabolome database showed that 23 out of the 31 products detected were present in the database. Addition of Sacoglottis gabonensis supplement to a Raphia sp. palm wine sample showed lower abundance of acetoin, acetic acid, methylpropyl lactate, ethyl octanoate and propyl acetate. We conclude that Sacoglottis gabonensis supplementation could suppress specific compounds during palm wine fermentation. This knowledge could be applied in new product development for the beverage.
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Some mineral profiles of fresh palm wine and those of seven brands of bottled palm wine were analysed using atomic absorption spectroscopy and the values were compared. Three of the bottled samples contained toxic levels of either Pb or Cd or both. Neither metal was detected in fresh palm wine. Zn, Cr and Ni were 2 to 15 times higher while Cu was 2 to 5 times lower in bottled samples than values for fresh sample. The likelihood of water-derived heavy metal contamination during bottling, and its potential health implication for consumers are discussed.
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Due to its tropical location, chains of mountains, inter-Andean valleys, Amazon basin area, eastern plains and shores on both the Atlantic and Pacific Oceans, Colombia has many ecosystems and the second largest plant biodiversity in the world. Many plant species, both native and naturalized, are currently recognized as toxic for both animals and humans, and some of them are known to cause their toxic effects due to their alkaloid content. Among these, there are plants containing the hepatotoxic pyrrolizidine alkaloids, neurotoxins such as the indolizidine alkaloid swainsonine and the piperidine alkaloids coniine and -coniceine and tropane alkaloids. Unfortunately, the research in toxic plants in Colombia is not nearly proportional to its plant biodiversity and the scientific information available is only very scarce. The present review aims at summarizing the scarce information about plant alkaloid toxicosis in animals and humans in Colombia.
Unlabelled: Palm wine produced traditionally and consumed by many people in the South-West of Burkina Faso is subject to alteration. In this study, we carried out a follow-up of two palm wines' fermentation during the 10 days in which palm wines are classically produced and consumed. We monitored biochemical characteristics of fermenting wines as well as followed the microflora kinetics using culture-dependent and culture-independent methods. The analysis of the acid content and the bacterial population revealed the correlation between the development of Lactic acid bacteria, acetic acid, and total acidity. Ribosomal intergenic spacer analysis and sequencing results revealed different yeast and bacterial populations for the two palm wines. Although Saccharomyces cerevisiae remained the sole yeast species in one fermentation, it was quickly replaced by Clavispora lusitaniae in the second fermentation, which had never been described until now in palm wine. When considering bacteria, the species Corynebacterium sp., Lactobacillus casei, Lactobacillus paracasei and Leuconostoc sp. were detected in both palm wines. But we also detected Acetobacter pasteurianus, Bacillus cereus and Bacillus thuringiensis in the second fermentation. Significance and impact of the study: Our results highlight the evolution of palm wine during the 10 days separating palm tapping and consumption of the fermented wine. The fermentation step is performed within few hours and completed after 24 h. The next days, its acidity increases progressively with the production of lactic and acetic acids by bacteria. The high production of acetic acid is very likely one of the main cause of palm wine degradation during this period. This indicates that the solution to palm wine preservation might be protection against oxygen, as well as the limit of bacterial growth through the use of preservatives.
Colon cancer is the third leading cause of cancer mortality worldwide, which results from interactions of different factors. It is frequently a pathological consequence of persistent inflammation. Diabetes affects several cancers and is positively correlated with the incidence of colon cancer. This study aimed to study the effect of exenatide in ameliorating inflammation, angiogenesis and cell proliferation in 1,2-dimethyl hydrazine (DMH) induced colorectal carcinoma in diabetic mice. Mice were randomly allocated into six groups, 8 mice each. Group 1: vehicle control group. Group 2: diabetic control group. Group 3: DMH control group: diabetic mice treated with DMH (20 mg/kg/week, s.c.) for 15 week. Group 4: DMH-cisplatin group: mice received cisplatin (4 mg/kg/week, i.p.). Groups 5 & 6: DMH-exenatide (10 and 20 μg/kg) group: mice received exenatide (10 or 20 μg/kg/day, s.c.), respectively. The present results highlighted an increase in angiogenic markers and cell proliferation in the DMH-diabetic group in comparison with the control group with greater expression of endothelial marker (CD34) and Ki-67 in colon tissue. Monotherapy with cisplatin or exenatide (10 and 20 μg/kg) downregulated these markers to different extents. The current results provided evidence that exenatide represents a promising chemopreventive effect against DMH-induced colon carcinogenesis in diabetic mice, at least in part, attributed to its anti-angiogenic and anti-proliferative mechanisms.
Benzylisoquinoline alkaloids (BIAs) are a family of ∼2500 alkaloids with both potential and realized pharmaceutical value, including most notably the opiates such as codeine and morphine. Only a few BIAs accumulate readily in plants, which limits the pharmaceutical potential of the family. Shifting BIA production to microbial sources could provide a scalable and flexible source of these compounds in the future. This review details the current status of microbial BIA synthesis and derivatization, including rapid developments in the past 6 months culminating in the synthesis of opioids from glucose in a microbial host.