Akademik Veri Yönetim Sistemi
Çetin B., Tunçil Y. E.(Yürütücü)
TÜBİTAK Uluslararası İkili İşbirliği Projesi, 2021 - 2023
Increased
consumption of resistant starch or its derivatives has been shown to promote
butyrogenic bacteria and butyrate levels in the colon, which is associated with
beneficial health outcomes, including suppressing
the development of carcinogenesis, obesity, type-2-diabetes and inflammation.
Accordingly, increased amount of resistant starch consumption is suggested.
However, undesired pasting and gelling properties of resistant starch as well
as its instability in food formulations restrict its application as a prebiotic
(butyrate promoting) ingredient in many food products. Thus, there is a need
for developing functional ingredients that is chemically similar to, but do not
possess the undesirable technological properties of, starch.
Since the
last decade, different types of α-glucans, that possess starch-like structures have
been biocatalytically synthesized, which are mainly used to lower the glycemic index
of starch. Moreover, the majority of such glucans have been shown to resistant
to mammalian digestive enzymes. Thus, they have great potential to show
butyrogenic effect as high as starch. However, there is no study conducted to
test the butyrogenic potentials of enzymatically synthesized α-glucans. This
project aims to fill this gap in the literature and discover optimum α-glucan
structure that reveals high butyrogenic activity and thus could be utilized
as a healthy ingredient for the productions of functional and medicinal foods. Further,
it is aimed to determine and isolate the beneficial microbial strain(s) from
the human feces that are promoted by the enzymatically synthesized α-glucan.
The working
hypothesis of the
project is that since the enzymatically synthesized α-glucans possess
starch-like chemical structures (glucose units linked via α-1,4 and α-1,6
linkages), they could promote butyrogenic bacteria, thereby increasing the
butyrate level in the colon. The
primary objective is to enzymatically
synthesize α-glucans that have distinct structural features and determine their butyrogenic capacity. The goal is to enzymatically
synthesize insoluble α-glucans having different branching ratios using a simultaneous one-pot reaction approach
and investigate their effects on colonic microbiota composition in vitro
using 16S rRNA sequencing technology and on microbial metabolites by measuring
the amounts of short chain fatty acids using gas chromatography. Moreover, applicability
of the α-glucan (that is found to reveal
the highest butyrogenic effect) in food formulations will be evaluated using bread and yogurt as model foods. Additionally,
the microbial strain(s) that are favored by the α-glucan will be identified and isolated using both enrichment and plating techniques under
anaerobic conditions.
Our expected
results are that we will explore the optimum α-glucan structure that promotes
butyrate producing bacteria and butyrate in the colon. Additionally, we will
identify and isolate microbial strain(s) that are favored by α-glucan of our
interest. These nutrients can be utilized as functional ingredients in the food
industry for the productions of healthy foods and can be directly extended to
studies in animals/humans. The positive impact of this work is to
advance our understanding of the connections between dietary fiber chemical
structures and colonic microbiome and to discover new functional food
ingredients that would have the potential to be patented and
commercialized for the productions of functional and medicinal foods.
An international collaboration as proposed here will be important to carry out this
multidisciplinary project, as it requires multiple partners who complement each other in the areas of carbohydrate
chemistry and microbiology. Moreover,
such collaboration will increase our interaction with the South Korean Scientists
(Dr. Byung-Hoo Lee's group), thereby allowing us to conduct internationally collaborative
projects in future, which will scientifically increase the visibility of jointing
institutions and countries world-wide.