54 / 116
ANTH-001
Vaccinium fruit anthocyanins are more complex than Acai
anthocyanin profiles. There are 3 common species that
share the common name Acai. The different Acai species
each have a slightly different anthocyanin profile (refer to
Yamaguchi et al. (2015) Food Chemistry, 179:137-151,
Schauss et al. 2006 JAFC 54:8598-8603, Schauss et al. 2006
JAFC 54:8598-8603). Authors did not identify three Acai
species available (Euterpe edulis, E. precatoria*, or E.
oleracea*; *are the typical commercially available species).
As diode array detectors (DAD) are more commonly
available to researchers and commercial laboratories,
authors should also have included one as well. DAD peak
spectra provide valuable anthocyanin identification
information. Just separating the 2 predominate Acai
anthocyanins that the authors’ report (possibly incorrectly
identified), while ignoring the additional anthocyanins in
Acai is not sufficient. Examining the minor anthocyanins in a
fruit sample can sometimes determine whether a sample is
adulterated or not (see 3 references mentioned previously).
The anthocyanin identifications and the Acai species used in
this work are questionable.
Supporting Data
General Comments
Anthocyanin SMPR requested an anthocyanin fingerprinting
method for Vaccinium fruit. This method demonstrated
cyanidin-glucoside and cyanidin-rutinoside could be
separated and quantified. But, a method that can only
detect two anthocyanins is not sufficient.
Method Optimization
Will have to demonstrate Vaccinium fruit anthocyanins can
be separated (probably will need a longer analytical column
to achieve this.) Need to include DAD. There is long-term
confusion if only plant common names are used; genus and
species information have to be included. If possible, analyze
NIST cranberry sample, though even this needs to be done
with caution. While NIST published anthocyanin data of this
cranberry reference material, unfortunately their cranberry
anthocyanin identifications were incorrect (see “Lowenthal
et al. (2013). Analytical and Bioanalytical Chemistry, 405,
4451-4465.”; this paper identified cranberry anthocyanins
incorrectly, or NIST reference material was not authentic
cranberry).
Performance Characteristics
Analytical Range:
Not applicable. SMPR was for a qualitative method.
LOQ:
Not applicable. SMPR was for a qualitative method.