Generality on probiotics used in food industry and theirs benefits on health

1. Probiotics
M. ANZA Adamou

2. Introduction
– Modern lifestyle has a strong impact on eating habits. The increased consumption
of processed foods and so-called fast foods is causing perceptible effects on
health. Eating is a fundamental aspect of life that goes well beyond nutrition,
having strong social and psychological implications. Eating is associated with
pleasure, so the compromise between health and indulgence is a profound
dilemma in modern society (Illanes & Guerrero, 2016). Foodborne illness has a
significant impact on public health, and also has economic consequences due to
lost working time and use of medical resources. Measures to reduce foodborne
illness therefore benefit both the individual and the society as a whole (Likotrafiti
& Rhoades, 2016). Hence the importance of bacteriotherapy in the production of
food in order to provide consumers with a food containing bio-active compounds
which confer benefits, in particular by preventing infections. In the rest of this
paper, we will present the prebiotics.

3. Concept of probiotic
– Microbes have been part of daily diet for centuries, but the concept of
‘probiotics’ has evolved relatively recently. In 1907, Elie Metchnikoff, the
Russian-born Nobel Prize winner, suggested the use of beneficial microbes to
replace harmful microbes and pathogens in the human gut. The term ‘probiotic’
was extensively acknowledged in 1960 by Lilly and Stillwell, who suggested
probiotics as substances produced by microorganism that promote the growth
of other microbes. Fuller defined a probiotic in 1989 as “a live microbial feed
supplement, which beneficially affects the host animal by improving its
intestinal balance.”

4. Concept of probiotic
– Another definition was suggested by Havenaar and Huis in’t Veld in 1992, which
defines a probiotic as “a viable mono or mixed culture of bacteria which when
applied to animal or man, beneficially affects the host by improving the
properties of indigenous flora.” Keeping all the recent developments and trends
in consideration, FAO/WHO 2002 guidelines defined probiotics as “live
microorganisms which when administered in adequate amount confer a health
benefit on the host.” (Kumar & Salminen, 2016).

5. Types of Microorganisms
– Lactobacillus and Bifidobacteria genera from lactic acid bacteria (LAB)
constitute the majority of the probiotics products (Abdollahi, Abdolghaffari,
Gooshe, & Ghasemi-Niri, 2016; Kumar & Salminen, 2016). Moreover, most of
them have a long history of safe use in food and are listed in the European QPS
list and/or the US GRAS notification list as safe for specific food uses. Therefore,
lactic acid bacteria and Bifidobacterium are probably the best models for
probiotic use or health effect characterization. However, members of the
genera Streptococcus, Enterococcus, Saccharomyces, Bacillus, Escherichia,
Propionibacterium, and Lactococcus have also been explored for probiotic
attributes. In each case, the assessment should start from the potential safety
issues and then continue to the demonstration of efficacy and health benefits
(Kumar & Salminen, 2016).

6. Types of Microorganisms
– The major Lactobacillus species that are considered or studied for probiotic
attributes include Lactobacillus acidophilus, Lactobacillus amylovorus,
Lactobacillus casei, Lactobacillus crispatus, Lactobacillus delbrueckii subsp.
bulgaricus, Lactobacillus gallinarum, Lactobacillus gasseri, Lactobacillus
johnsonii, Lactobacillus paracasei, Lactobacillus plantarum, Lactobacillus reuteri,
and Lactobacillus rhamnosus. Lactic acid bacteria are acid-tolerant and
fermentative in nature and have been used as starter cultures in the majority of
fermented foods (Kumar & Salminen, 2016).
– Lactic acid bacteria in general have the intrinsic capacity to tolerate low pH
values and high bile concentrations and to adhere to intestinal cell lines.

7. Types of Microorganisms
– Molecular studies have revealed that a large proportion of their genomes are
attributed to sugar utilization and transportation.
– Additionally, intestinal adaptation is also apparent, for example, with respect to
the presence of mucous-binding protein and bile salt hydrolase genes in
Lactobacillus plantarum and adhesion protein in Lactobacillus acidophilus
(Kumar & Salminen, 2016).
– Bifidobacterium spp. have also been extensively used in product formulations
and probiotic applications as they share many phenotypic characteristics with
lactobacilli. In comparison with lactobacilli, bifidobacteria inhabit very limited
niches, such as human and animal GI tracts and, in some cases, insect
intestines.

8. Types of Microorganisms
– The major species that were isolated and studied include B. adolescentis, B.
angulatum, B. animalis subsp. lactis, B. bifidium, B. breve, B. catenulatum, B.
dentium, B. longum, and B. pseudocatenolatum.
– Genomic studies of Bifidobacterium strains revealed that they can utilize a
broad range of complex carbohydrates such as inulin-type fructans,
arabinogalactans, arabinoxylans, and starch. Exclusive operons have been
evolved for specialized purposes, as the degradation of amylopectin by B. breve
strains and the utilization of a broad range of simple sugars by B. dentium.
Bifidobacterium strains also show changes at transcriptome and proteome level
in intestinal conditions or gut environment (Kumar & Salminen, 2016).

9. Types of Microorganisms
– Among a variety of existing strains, there are several properties that should be
present in a strain to be considered for probiotic usage. They should have
resistance to gastric and bile acidity, capability of adherence to mucus or
epithelial cells, antimicrobial activity against potential pathogenic bacteria or
fungi, capacity to reduce adhesion of pathogens to intestinal surfaces, and bile
salt hydrolase activity (Chang Hwan Choi et al., 2011; Seale & Millar, 2013;
Tulumoglu et al., 2013)
– Additionally, all initial screening and detailed characterization should follow
WHO/FAO guidelines. The major steps include strain identification using
molecular tools, functional characterization using in vitro and in vivo models,
double-blind controlled human trials, and formulation assessment and quality
control (Kumar & Salminen, 2016).

10. Health Effects
–
Apart from the positive effect of
probiotics on general wellbeing,
there are several particular
clinical symptoms or conditions
that are reported to be
beneficially affected by the use
of specific probiotics. Such
conditions include diarrhea,
gastroenteritis, inflammatory
bowel disease, irritable bowel
syndrome, Crohn’s disease, and
alleviation of symptoms of
lactose intolerance.

11. Health Effects
 Effects on Intestinal Disorders
– Probiotics find applicability in diarrheal cases that could be caused by viral or
bacterial infection or could be antibiotic associated diarrhea. It should also be
noted that efficacy of probiotic strains depends on the type of diarrhea. For
instance, probiotics are found to be effective against rotavirus-associated
diarrhea. The major probiotic strains used for clinical applications in children
belong to Saccharomyces boulardii, Lactobacillus rhamnosus, and Lactobacillus
reuteri. For instance, some studies highlight the use of Lactobacillus rhamnosus
GG for Clostridium difficile-associated diarrhea and the prevention of the onset
of pouchitis. The possible mechanism could be due to an immunomodulatory
role, probably by increase in secretory IgA.

12. Health Effects
 Effects on Intestinal Disorders
– Some probiotic bacteria also secrete antimicrobial peptides, that is,
bacteriocins, which could inhibit the growth of certain enteric pathogens. It is
also believed that probiotic microorganisms compete with pathogenic viruses or
bacteria for intestinal binding sites. Inflammatory bowel diseases, such as
Crohn’s disease and ulcerative colitis, are marked by high immune responses to
gut microbes. Probiotics have found application in alleviating inflammatory
conditions in the gut, which could be due to the stimulation of host immune
response that may include immune cell proliferation, enhanced phagocytic
activity, increase in secretory IgA, and shifts in overall microbial composition.

13. Health Effects
 Effects on Intestinal Disorders
– Some lactic acid bacteria, including Lactobacillus delbrueckii subsp. bulgaricus
and Streptococcus thermophilus, also may improve lactose intolerance through
the production of lactase. Therefore, fermented dairy products like yogurt are
widely recommended for regulating lactose intolerance. In case of constipation,
it is believed that lactic acid bacteria secrete organic acids that modify the
intestinal microbiota and increase intestinal motility due to lowering of pH or
shortening of transit time (Kumar & Salminen, 2016).

14. Health Effects
 Prevention of Allergies
– Probiotics may exhibit antiallergic effects by degradation or structural
modification of enteral antigens, stabilization of aberrant microbiota,
improvement of the gut-barrier function, regulation of the secretion of pro
inflammatory mediators, and development of the immune system. Probiotic
intervention studies in children have shown that there is significant reduction in
cumulative incidence of eczema and IgE-associated eczema. Evidence also
suggests that probiotic administration during pregnancy may reduce the risk of
eczema during the first year of life. In the case of food allergies, infants that
were fed with Lactobacillus rhamnosus GG showed an increase in tolerance to
cow’s milk protein.

15. Health Effects
 Prevention of Allergies
– Interactions between gut microbiota and probiotics have significant roles in
immune regulation and predisposition to allergy. Moreover, present knowledge
suggests that singular clinical reports cannot be extrapolated for general usage
or as a therapeutic alternative for allergy treatment yet. Indeed, properties are
strain-specific and the exact mechanisms of action remain to be elucidated
(Kumar & Salminen, 2016).

16. Health Effects
 Anticarcinogenic Activities
– Several probiotic strains belonging to Bifidobacterium spp. And Lactobacillus
spp. were claimed to have anticarcinogenic, antimutagenic, and antitumorigenic
activities in different animal models. Short-chain fatty acids produced by the
intestinal microbiota play very important roles in the maintenance of colonic
mucosal health. Yet, probiotic strains in general do not produce anticarcinogenic
butyrate, in contrast to gut bacteria from the clostridial clusters IV and XIVa. The
latter butyrogenic bacteria may nevertheless be stimulated by the
administration of certain probiotics through cross-feeding mechanisms.

17. Health Effects
 Anticarcinogenic Activities
– Mechanism for anticarcinogenic activity of butyrate may be due to the
inhibition of proliferation, induction of apoptosis, or differentiation of tumor
cells. Probiotics also influence carbohydrate and protein fermentation,
enriching microbiota with high saccharolytic activity and low proteolytic activity.
Proteolytic fermentation end products or metabolites are potentially toxic and
microbial manipulation or dietary modification toward saccharolytic
fermentation is highly desirable. However, there are very few studies that claim
efficacy of probiotics, prebiotics, or synbiotics with potential anticarcinogenic
activity in humans (Kumar & Salminen, 2016).

18. Health Effects
 Use of Probiotic in Controlling Blood Cholesterol
– Elevated blood cholesterol levels signify increased risks for cardiovascular and
related diseases. It has been suggested that incorporation of probiotics in
dietary supplements may help control serum cholesterol levels. Lactobacillus
acidophilus and lactis that were incorporated in yogurt may thus lower total
cholesterol levels in serum. In vitro assays revealed that lactobacilli can
precipitate cholesterol from the media and deconjugate bile salts. However, the
cholesterol lowering capacity is possibly strain-specific and, more importantly,
human intervention studies are not conclusive (Kumar & Salminen, 2016).

19. Probiotic fermented foods
– Probiotics can be included in many different foods, fermented and unfermented.
The food matrix is known to have an important role in the stability of probiotics
(Forssten et al., 2011). Manufacturers take this into account when developing such
foods. However, which role the matrix plays in efficacy is less well understood. For
some strains it does not seem to play a role, while it does for others. This topic
requires further investigation and is not discussed here owing to lack of information.
It is important to realise that diet is likely to be a bigger cause of variation than the
matrix of one or another probiotic food (Kelly, Colgan, & Frank, 2012).
– Numerous fermented foods exist, but not all of these food classes can be linked with
the probiotic concept, such as alcoholic beverages and fermented meats, or foods in
which the fermentations merely fulfil a technological function in the processing of
the food, such as in coffee, tea and cocoa (Ouwehand & Röytiö, 2015).

20. Fermented dairy foods/beverages
– Fermented dairy foods are the most widely used carriers of probiotics in
Western societies, in particular yogurt and yogurt-type drink products. This may
have historic reasons as mentioned above, but it has also practical reasons.
Most commercially available probiotics belong to the genera Bifidobacterium
and Lactobacillus. Members of these genera tend to grow well in milk, and it
may even be their most common habitat. In fermented probiotic dairy products,
probiotics are usually accompanied by starter cultures such as Lactobacillus
delbrueckii subsp. bulgaricus and/or Staphylococcus thermophilus. There are
two main reasons for the inclusion of starter cultures in a probiotic product. The
first is technological: starter cultures provide structure and flavor to the
product.

21. Fermented dairy foods/beverages
– In addition, starter cultures support functionality; some probiotics do not grow
well as a pure culture in milk and grow better in symbiosis with a starter culture.
Besides fresh fermented dairy products, probiotics can be included in non
fermented milk such as the so-called “sweet acidophilus milk”. The milk is not
sweet in the sense of sweet taste, but is referred to as such because it is not
sour. Furthermore, probiotics can be included in cheese. Despite the long
ripening and shelf life of cheese, probiotic counts appear to be stable in cheese
for months. By optimizing fermentation techniques, it is feasible to produce a
good-quality cheese with high probiotic counts so that a standard portion of
cheese (15g) provides a dose of at least 109CFU (Ouwehand & Röytiö, 2015).

22. Fermented plant foods/beverages
– Lactic fermented plant foods are common in Asian, African and East European
societies. These are fermented vegetables such as sauerkraut and kimchi, which
are mainly based on spontaneous fermentations dictated by the storage
conditions and ingredients used for this fermentation (Jung et al., 2011). Lactic
fermented cereals are common, such as in sourdough, although obviously
subsequent processing (baking) will not allow survival of microbes. Lactic
fermentation of cereals otherwise contributes to improved flavour and reduces
phytic acid activity, thereby improving biological availability of minerals such as
iron (Ouwehand & Röytiö, 2015).

23. Fermented plant foods/beverages
– Lactic acid bacteria involved in the fermentation may also produce vitamins, in
particular B vitamins. Traditionally, fermented foods of vegetable or cereal
origin have not been used as carriers for probiotics. However, it cannot be
excluded that the microbes involved in these fermentations have a direct
influence on health, similar to a probiotic. Specifically designed foods are
successfully marketed, usually on the basis of fermented cereals, and have been
studied as probiotic carriers. Such products have only sporadically been used as
carriers of probiotics. The stability of selected probiotics in fermented cereal-
based products has been documented to be good (Ouwehand & Röytiö, 2015).

24. Other carriers of probiotics
– Probiotics have been included successfully in ice cream. Relevant to this book is
the production of ice cream based on frozen yogurt, which basically follows the
same manufacturing as probiotic yogurt. But probiotics can also be included in the
ice cream base or in a chocolate coating of the ice cream. As mentioned earlier,
supplements are probably the most common format for probiotic consumption, in
addition to dairy products. Furthermore, probiotics have been included in fruit
juices, which is particularly challenging because of the low pH (<4) and the
presence of various natural antimicrobial components in fruits (such as benzoate
and anthocyans). Probiotics have also been included in chocolate, providing
extremely long shelf lives of up to 2 years – not so much to produce probiotic
chocolate bars, but to provide a probiotic-carrying chocolate coating to various
foods. These applications fall outside the focus of this chapter, but indicate that
formats for probiotics exist (Ouwehand & Röytiö, 2015).

25. Some of the commercially available
probiotic microorganisms adapted from (Kumar &
Salminen, 2016)

26. References
– Illanes, A., & Guerrero, C. (2016). Functional Foods and Feeds.
35-86. doi:10.1016/b978-0-12-802724-0.00002-0
– Kumar, H., & Salminen, S. (2016). Probiotics Encyclopedia of
Food and Health (pp. 510-515). Oxford: Academic Press.
– Likotrafiti, E., & Rhoades, J. (2016). Probiotics, Prebiotics,
Synbiotics, and Foodborne Illness. 469-476. doi:10.1016/b978-
0-12-802189-7.00032-0
– Ouwehand, A. C., & Röytiö, H. (2015). Probiotic fermented foods
and health promotion. 3-22. doi:10.1016/b978-1-78242-015-
6.00001-3
– Seale, J. V., & Millar, M. (2013). Probiotics: a new frontier for
infection control. J Hosp Infect, 84(1), 1-4.
doi:10.1016/j.jhin.2013.01.005
– Tulumoglu, S., Yuksekdag, Z. N., Beyatli, Y., Simsek, O., Cinar, B.,
& Yasar, E. (2013). Probiotic properties of lactobacilli species
isolated from children's feces. Anaerobe, 24, 36-42.
doi:10.1016/j.anaerobe.2013.09.006
– Jung, J. Y., Lee, S. H., Kim, J. M., Park, M. S., Bae, J. W., Hahn, Y., et
al. (2011). Metagenomic analysis of kimchi, a traditional Korean
fermented food. Applied and Environmental Microbiology, 77,
2264–2274.
– Forssten, S. D., Sindelar, C. W., & Ouwehand, A. C. (2011).
Probiotics from an industrial perspective. Anaerobe, 17, 410–413.
– Kelly, C. J., Colgan, S. P., & Frank, D. N. (2012). Of microbes and
meals: the health consequences of dietary endotoxemia. Nutrition
in Clinical Practice, 27, 215–225.
– Abdollahi, M., Abdolghaffari, A. H., Gooshe, M., & Ghasemi-Niri, F.
(2016). Safety of Probiotic Bacteria. 227-243. doi:10.1016/b978-0-
12-802189-7.00015-0
– Chang Hwan Choi, Sun Young Jo, Hyo Jin Park, Sae Kyung Chang,
Jeong-Sik Byeon, & Myung, S.-J. (2011). A Randomized, Double-
blind, Placebo-controlled Multicenter Trial of Saccharomyces
boulardii in Irritable Bowel Syndrome Effect on Quality of Life.
– Illanes, A., & Guerrero, C. (2016). Functional Foods and Feeds. 35-
86. doi:10.1016/b978-0-12-802724-0.00002-0