Oligosaccharides in food matrix and the feasibility in coffee brews

Analytics for the discovery of bioactive
compounds in agricultural products
and by-products
Daniela Barile
[email protected]
Assist. Professor
Food Science & Technology
Residual side streams from the
food industry and agriculture
Effluents
High levels of organic matter
Cause environmental problems if released in
the environment
May still contain Bioactive molecules
Potential for re-utilization of streams
Oligosaccharides-What are they and
what do they do
Oligosaccharides: carbohydrates generally
consisting of 2-20 monomeric residues
Found in: Plants and mammalian milks
Origin:
Synthesized in vivo
Hydrolysis of higher oligosaccharides,
polysaccharides
Oligosaccharides Functions
Immune
system
activation
Antibacterial
and antiviral
Selective
prebiotics
Development
of nervous
system
Gut
barrier
function
Decrease
hypersensitivity
reactions
PREBIOTICS
Non-digestible oligosaccharides
INTENTIONALLY feed SELECTIVELY
only beneficial bacteria
Guide the microbiota in the right
direction
Biotherapeutic
Oligosaccharides
• Accurate analytical
characterization
• Identification in
streams/commodities
• Adequate supply
• Homogeneity of composition
& Isolation technologies
GLYCOMICS
Lagged behind the other OMICS
proteomics and genomics
Connection sites
Chiral Centers
•NO CHROMOPHORE
CH2OH
•BRANCHING
•MULTIPLE LINKAGES
OH
CH2OH
OH
O
O
O
OH
OH
O
OH
OH
•Heterogeneity(compositions)
•Numerous isomers for each
Isomers
oligosaccharide
Retention time
Analytical platform
http://barilelab.ucdavis.edu/
• High Mass Accuracy (2 ppm)
• High Mass Resolution
• High throughput profile
MALDI-TOF MAXIFLEX
Bruker Daltonics
NANO-LC CHIP QUADRUPOLE TOF
Agilent Technologies
Oligosaccharides Discovery & Characterization
• SEPARATION OF ISOMERS
• REPRODUCIBLE RETENTION TIMES
• PARTIAL STRUCTURAL
ELUCIDATION
• ASSEMBLE BIOINFORMATIC
LIBRARIES
• RAPID IDENTIFICATION IN
UNKNOWN SAMPLES
Previous Projects (i):
Recovery of Oligosaccharides
from dairy streams (Cheese Whey)
Cheese Whey Permeate
milk
RENNET
10%
90%
CHEESE
WHEY
FILTRATION
Retentate
WPC (+$$$)
Permeate
(no value)
Disposal
costs (-$)
Over 50 BMO
Many identical/similar to human
milk
Large fucosylated oligosaccharides
How to validate the predicted
biological activities?
UCD Milk
Processing Lab
The UC Davis
Milk Processing Lab
Membrane filtration
Refine
oligosaccharides
formulation
Industry Side
Streams
Characterization and
Q.C.
Clinical
testing
Example of process optimization:
Enzymatic Lactose Hydrolysis by
ß-galactosidase
Y=96.44 – 0.86X12 -0.87X32
For each processing step, we use software to carry on modeling and study
the interaction of multiple variables simultaneously.
This graphic shows higher hydrolysis rate in the center (red color) which
correspond to optimal values of pH and amount of enzyme.
Mechanistic study:
understanding which sugars are most consumed by
the bacteria during in-vitro fermentation
4
Control
1
Bifidobacterium infantis
supernatant
Bifidobacterium infantis
Supernatant (rep)
3
3
2
1
1
Moving forward
with new bioactives
2009: characterization of Oligosaccharides in whey
2013: completed the first human trial
Pave the way toward efficacy trials in the target
population (i.e. infants and children)
Evidence-based food functionality
Unprecedented level of accuracy and detail
Previous Projects (ii):
Identification of oligosaccharides in Wine
and wine streams
Hypothesis
Wine contains low molecular weight
free oligosaccharides deriving from the
degradation of cell wall polysaccharides
(modified and/or hydrolyzed either
during the maturation of grapes or/and
during wine making)
Oligosaccharides extraction and
analysis (DP 3 -> 15)
CONCENTRATE
(from 1L to 0,1L)
SPE purification
C18:remove proanthocyanidins and anthocyans
GCC: remove monosaccharides, salts
Gas chromatography & Mass
Spectrometry Analysis
>100 mg/L of oligosaccharides
in both red and white wines
Previous projects (iii):
Oligosaccharides in Hazelnut
by-products
Identification of fiber-rich materials, potential
source of prebiotic oligosaccharides
hazelnut skin:
by-product of the conventional
industrial roasting process
Over 100
hazelnuts in each
jar!
In collaboration with:
Enzymatic Treatments to release
oligosaccharides
• No enzymatic treatments
• Pancratin treatments
• Pepsin treatments
• Vicozyme treatments
• Pancreatin, pepsin, Viscozyme treatments
Note: all prebiotics carbohydrate are fiber
but not all fibers are necessarily prebiotics!
Oligosaccharides extraction
and purification
Prebiotic effect of hazelnut oligosaccharides on
Lactobacillus plantarum & Lactobacillus crispatus
Montella et al., J. Funct. Foods (2013) 1 (5) 306-315
Over 30g of
prebiotic
oligosaccharides
/kg extract
Investigating the Functional
Properties of Coffee
and Coffee Streams
Coffee: From Beans to Brews
Coffee: important commodity worldwide
Consumed for over 1,000 years
Generally prepared from two species (or their blends):
Coffea arabica (Arabica), considered as the noblest of all
coffee plants (75% of world’s production)
Coffea canephora (Robusta), considered to be more acid
but more resistant to plagues, (25% of world’s production)
Coffee: From Beans to Brews
In addition to caffeine, coffee contains
hundreds of potentially bioactive
components, such as polyphenols,
melanoidins, complex carbohydrates, etc
Bean Processing: Roasting
Changes in chemical composition :
Transformation of naturally occurring
carbohydrates and polyphenolic
constituents into a complex mixture
Maillard reaction products
Formation of small organic molecules
from pyrolysis
Oxidation, thermal degradation,
hydrolysis, isomerization, polymerization
and other complex sugar reactions
Coffee: Waste Stream
The average consumption in the US is 3.2 cups of coffee
per day (for the coffee drinkers)
Due to the great demand of coffee and coffee beverages,
large amounts of waste streams are generated in the
coffee industry
Industrial coffee residues are often disposed of
inappropriately and represent an environmental
concern
Important topic that need to be further explored
Coffee production:
Examples of Waste Streams
Coffee Silverskin and spent
coffee grounds are coffee
residues
Coffee Silverskin is obtained
during bean roasting
Spent coffee grounds derive
from instant coffee
preparation
Polysaccharides in Coffee Beans
Arabinogalactan
Galactomannans
Monomers: Arabinose and Galactose
Monomers: Mannose and Galactose
Linkage: (1→3)-linked β-galactose substituted at O-6
with arabinose and/or galactose residues
Linkage: (1→4)-linked β-mannan chains substituted
at O-6 with single galactose residues approximately
every 100 residues
Structural modifications promoted by roasting are not
fully understood
Coffee oligosaccharides:
in vivo studies
Conclusion
Coffee residues are rich in polysaccharides, proteins,
and minerals
Identifying alternatives for use of coffee industrial
residues is of great importance due to their potential
beneficial activities
Only limited characterization of oligosaccharides
No bioinformatic libraries available yet
The tools to carry on detailed characterization and
mechanistic studies of bioactivity are available
Thank you!
The Peter J.
Shields Endowed
Chair in Dairy Food
Science