Banaba (Lagerstroemia speciosa L.): An evidence-based systematic review by the natural Standard Research Collaboration

Abstract

This study is an evidence-based systematic review including written and statistical analysis of scientific literature, expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing.

Full text

NATURAL STANDARD REVIEW
Catherine Ulbricht, PharmD, Column Editor
Banaba (Lagerstroemia speciosa L.):
An Evidence-Based Systematic
Review by the Natural Standard
Research Collaboration
Catherine Ulbricht, PharmD
Chi Dam, PharmD
Tamara Milkin, PharmD
Erica Seamon, PharmD
Wendy Weissner, BA
Jen Woods, BS
ABSTRACT. This study is an evidence-based systematic review includ-
ing written and statistical analysis of scientific literature, expert opinion,
folkloric precedent, history, pharmacology, kinetics/dynamics, interac
-
tions, adverse effects, toxicology, and dosing.
doi:10.1300/J157v07n01_09
Catherine Ulbricht is affiliated with Massachusetts General Hospital. Chi Dam is
affiliated with the Northeastern University. Tamara Milkin is affiliated with the North
-
eastern University. Erica Seamon is affiliated with the Nova Southeastern University.
Wendy Weissner is affiliated with the Natural Standard Research Collaboration. Jen
Woods is affiliated with the Northeastern University.
Natural Standard Review (www.naturalstandard.com) Copyright © 2006. Reprinted
with permission.
Journal of Herbal Pharmacotherapy, Vol. 7(1) 2007
Available online at http://jhp.haworthpress.com
doi:10.1300/J157v07n01_09 99

KEYWORDS. Adverse effects, banaba, crepe myrtle, dosing, evi
-
dence-based, interactions, Lagerstroemia speciosa, pharmacodynamics,
pharmacology, pharmacokinetics, pride-of-India, systematic review,
queen’s flower
SEARCH STRATEGY
To prepare each Natural Standard review, electronic searches are con
-
ducted in nine databases, including AMED, CANCERLIT, CINAHL,
CISCOM, the Cochrane Library, EMBASE, HerbMed, International
Pharmaceutical Abstracts, Medline, and NAPRALERT. Search terms
include the common name(s), scientific name(s), and all listed syn-
onyms for each topic. Hand searches are conducted of 20 additional
journals (not indexed in common databases), and of bibliographies
from 50 selected secondary references. No restrictions are placed on
language or quality of publications. Researchers in the field of comple-
mentary and alternative medicine (CAM) are consulted for access to ad-
ditional references or ongoing research.
Selection Criteria
All literature is collected pertaining to efficacy in humans (regardless
of study design, quality, or language), dosing, precautions, adverse ef-
fects, use in pregnancy/lactation, interactions, alteration of laboratory
assays, and mechanism of action (in vitro, animal research, human data).
Standardized inclusion/exclusion criteria are utilized for selection.
Data Analysis
Data extraction and analysis are performed by health care profession
-
als conducting clinical work and/or research at academic centers, using
standardized instruments that pertain to each review section (defining
inclusion/exclusion criteria and analytic techniques,
including validated measures of study quality). Data
are verified by a second reviewer.
Review Process
A blinded review is conducted by multidiscipli
-
nary research-clinical faculty at major academic
100 JOURNAL OF HERBAL PHARMACOTHERAPY

centers with expertise in epidemiology and biostatistics, pharmacology,
toxicology, complementary and alternative medicine (CAM) research,
and clinical practice. In cases of editorial disagreement, a three member
panel of the Editorial Board addresses conflicts, and consults experts
when applicable. Authors of studies are contacted when clarification is
required.
Update Process
Natural Standard regularly monitors scientific literature and industry
warnings. When clinically relevant new data emerge, best efforts are
made to update content immediately. In addition, regular updates with
renewed searches occur every 3-18 months, variable by topic.
SYSTEMATIC AGGREGATION, ANALYSIS,
AND REVIEW OF THE LITERATURE
Synonyms/Common Names/Related Substances
Banaba extract, banglang (Vietnam), bang-lang (Cambobia), bungor
(Malaya, Sabah), Byers wonderful white crapemyrtle, crape myrtle, crepe
myrtle, corosolic acid, ellagitannins (flosin B, reginin A, lagerstroemin),
flos-reginae Retz,Glucosol
TM
, glucosal, intanin (Thailand), jarul (India),
Lagerstroemia, Lagerstroemia indica, Lagerstroemia parviflora, Lager-
stroemia speciosa, leaf extract, lasubine, Lythraceae (family), lythraceae
alkaloids, Munchausia speciosa, Pride-of-India, pyinma, Queen’s crape
myrtle, Queens flower.
CLINICAL BOTTOM LINE/EFFECTIVENESS
Brief Background
Banaba is a medicinal plant that grows in India, Southeast Asia,
and the Philippines. Banaba has been used for blood sugar control. The
hypoglycemic effect of banaba leaf extract is similar to that of insulin,
which induces glucose transport from the blood into body cells.
1
Currently, preliminary research suggests that orally administered
banaba extract, standardized to 1% corosolic acid, may lower blood sugar
in people with type 2 diabetes,
2
however further evidence is needed be
-
fore a firm conclusion can be made.
Natural Standard Review 101

102 JOURNAL OF HERBAL PHARMACOTHERAPY
Natural Standard Evidence-Based
Validated Grading Rationale™
Grades reflect the level of available scientific evidence in support
of the efficacy of a given therapy for a specific indication.
Expert opinion and folkloric precedent are not included in this
assessment, and are reflected in a separate section of each review
(“Strength of Expert Opinion and Historic/Folkloric Precedent”).
Evidence of harm is considered separately; the given grades apply
only to evidence of benefit.
Indication Evidence Grade
Diabetes C
Scientific Evidence for Common/Studied Uses:
C (Unclear or conflicting scientific
evidence)
Evidence of benefit from >1smallRCT(s)
without adequate size, power, statistical
significance, or quality of design by objective
criteria,* OR conflicting evidence from multiple
RCTs without a clear majority of the properly
conducted trials showing evidence of benefit or
ineffectiveness, OR evidence of benefit from >
1
cohort/case-control/non-randomized trials AND
without supporting evidence in basic science,
animal studies, or theory, OR evidence of
efficacy only from basic science, animal studies,
or theory.
Level of Evidence Grade Criteria
A (Strong Scientific Evidence) Statistically significant evidence of benefit from
>2 properly randomized trials (RCTs), OR
evidence from one properly conducted RCT
AND one properly conducted meta-analysis, OR
evidence from multiple RCTs with a clear
majority of the properly conducted trials
showing statistically significant evidence of
benefit AND with supporting evidence in basic
science, animal studies, or theory.
B (Good Scientific Evidence) Statistically significant evidence of benefit from
1-2 properly randomized trials, OR evidence of
benefit from >
1 properly conducted meta-
analysis OR evidence of benefit from >1
cohort/case-control/non-randomized trials AND
with supporting evidence in basic science,
animal studies, or theory.

Historical or Theoretical Uses
Which Lack Sufficient Evidence
Antibacterial, anti-obesity, antitumor, antitussive, dyspepsia, hyper-
lipidemia, hypertriglyceridemia.
Expert Opinion and Folkloric Precedent
Banaba has been used for thousands of years in the Philippines and as
a folklore treatment by the native Indians and more recently used by the
Japanese, mostly as a tea preparation. The ability to reduce blood sugar
banaba leaves made a popular herbal decoction for controlling sugar
and weight loss.
3,4
Brief Safety Summary
Possibly Safe: Banaba is generally considered to be safe when taken
orally for 15 days for the treatment of Type II diabetes.
2
DOSING/TOXICOLOGY
General
Recommended doses are based on those most commonly used in avail
-
able trials, or on historical practice. However, with natural products it is
Natural Standard Review 103
Level of Evidence Grade Criteria
D (Fair Negative Scientific Evidence) Statistically significant negative evidence (i.e.,
lack of evidence of benefit) from cohort/case-
control/non-randomized trials, AND evidence in
basic science, animal studies, or theory
suggesting a lack of benefit.
F (Strong Negative Scientific Evidence) Statistically significant negative evidence (i.e.,
lack of evidence of benefit) from >
1 properly
randomized adequately powered trial(s) of high-
quality desig n by objective criteria.*
Lack of Evidence
†
Unable to evaluate efficacy due to lack of
adequate available human data.
*Objective criteria are derived from validated instruments for evaluating study quality, including the 5-point scale developed by
Jadad et al., in which a score below 4 is considered to indicate lesser quality methodologically (Jadad AR, Moore RA, Carroll D,
Jenkinson C, Reynolds DJ, Gavaghan DJ, McQuay HJ. Assessing the quality of reports of randomized clinical trials: is blinding
necessary? Controlled Clinical Trials 1996; 17[1]:1-12).
†
Listed separately in reviews in the “Historicalor Theoretical Uses which Lack Sufficient Evidence” section.

often not clear what the optimal dose should be to reconcile efficacy and
safety. Preparation of one product may vary from manufacturer to manu
-
facturer and from batch to batch. Because it is often not clear what the
active components of a product are, standardization may not be possible,
and consequently the clinical effects of different brands may not be com
-
parable.
Standardization
Lagerstroemia speciosa standardized to 1% corosolic acid (Glu
-
cosol
TM
has been used in a randomized clinical trial involving Type II
diabetics (non-insulin-dependent diabetes mellitus, NIDDM).
2
Adult Dosing (Age 18)
Oral
Diabetes: 32 mg and 48 mg daily for two weeks may significantly re-
duce blood glucose levels.
2
Pediatric Dosing (Age < 18)
Insufficient available evidence.
Toxicology
Oral LD
50
of water decoction in mice was 375 g/kg; tincture 810 mg/
kg.
5
PRECAUTIONS/CONTRAINDICATIONS
Allergy
Caution should be exercised in patients with known allergy/hyper
-
sensitivity to banaba, its constituents, or any members of the Lythraceae
family.
104 JOURNAL OF HERBAL PHARMACOTHERAPY

Adverse Effects/Post Market Surveillance
General: No adverse effects have been noted in the available research.
Precautions/Warnings/Contraindications
Use cautiously in patients with diabetes since banaba may lower
blood sugar.
2
Pregnancy and Lactation
Not recommended due to lack of sufficient data.
INTERACTIONS
Banaba/Drug Interactions
Anticoagulant/antiplatelet drugs: Lagerstroemia indica has been
shown to produce antithrombin activity.
6
Hypoglycemic drugs, insulin: According to animal data, Lythraceae
may increase the rate of glucose uptake and decrease the isoproternol-
induced glycerol release. Theoretically, banaba has been shown to produce
insulin-like actions.
7
Theoretically, banaba may have additive effects
when taken concomitantly with diabetic drugs.
7
Xanthine oxidase (XOD): The XOD-inhibitory effect of valoneic
acid dilactone (VAD), one of two active compounds of Lagerstroemia
speciosa leaves, was stronger than that of allopurinol, a clinical drug
used for XOD inhibitor.
8
The results may explain and support the dietary
use of the aqueous extracts from Lagerstroemia speciosa leaves for the
prevention and treatment of hyperuricemia.
Banaba/Herb/Supplement Interactions
Anticoagulant/antiplatelet herbs and supplements: Lagerstroemia
indica has been shown to produce antithrombin activity.
6
Hypoglycemic herbs and supplements: Herbs such as fenugreek, gar
-
lic, guar gum, and horse chestnut, which can lower blood glucose, theo
-
retically will have additive effects with banaba.
Natural Standard Review 105

Banaba/Food Interactions
Glucose: Banaba may influence glucose absorption.
9
Therapeutic
supplementation with banaba for the normalization of blood glucose
levels in humans with hyperglycemia may be beneficial.
10
Banaba/Lab Interactions
Blood glucose: Banaba may lower blood glucose levels.
2
Triglycerides: One lab study found that banaba may lower triglycer
-
ides.
4
MECHANISM OF ACTION
Pharmacology
Active constituents of banaba include corosolic acid and the el-
lagitannins: lagerstroemin, flosin B, and reginin A.
2,11,12
Banaba has
lowered blood glucose in both animals and humans.
2,12
In vitro studies
suggest that ellagitannins have an insulin-like effect.
11
Lagerstroemin
may activate insulin receptors.
7
According to studies in obese mice, banaba appeared to control
weight gain;
4
however, this effect has not been studied in humans.
Lagerstroemia indica has been shown to produce antithrombin ac-
tivity.
6
According to in vitro research, valoneic acid, a constituent of banaba,
has been demonstrated to possess xanthine oxidase inhibiting activity.
Pharmacodynamics/Kinetics
Soft gel formulation of Lagerstroemia speciosa has a better bio
-
availability than a dry-powder formulation.
2
HISTORY
Banaba is used in Asia, Australia, and the East Indies for timber. In
addition, because of its large showy flowers, the plant is commonly used
as an ornament. Banaba is the Tagalog name, Lagerstroemia speciosa
L., which has been used as a folk medicine for patients with diabetes in
the Philippines and Southeast Asia. Extracts from banaba leaves have
106 JOURNAL OF HERBAL PHARMACOTHERAPY

been reported to reduce diabetic symptoms in mice, reduce weight, and
lower lipids in the liver.
Condition
Refers to the medical condition or disease targeted by a therapy.
Study Design
Common types include the following:
•
Randomized controlled trial (RCT): An experimental trial in which
participants are assigned randomly to receive either an intervention
being tested or placebo. Note that Natural Standard defines RCTs
Natural Standard Review 107
Condition Study
Design
Author,
Year
N Statistically
Significant?
Quality of
Study
0-2=poor
3-4=good
5=excellent
Magnitude
of Benefit
ARR NNT Comments
Diabetes Randomized
controlled
trial
Judy,
2003
10 Yes 2 Small NA NA Soft gelatin
or hard
gelatin
formulation
of capsule
of 16, 32,
and 48mg
Glucosol
TM
sequentially
with 10-day
washout
period in
between
doses.
12345 6 7 8 9 10
Condition
Study
Design
Author,
Year
N
Statistically
Significant?
Quality of
study
0-2=poor
3-4=good
5=excellent
Magnitude
of Benefit
Absolute
Risk
Reduction
Number
Needed
to Treat
Comments
Explanation of Columns in Natural Standard Evidence Table

as being placebo-controlled, while studies using active controls are
classified as equivalence trials (see the list). In RCTs, participants
and researchers are often blinded (i.e., unaware of group assign
-
ments), although unblinded and quasi-blinded RCTs are also often
performed. True random allocation to trial arms, proper blinding,
and sufficient sample size are the basis for an adequate RCT.
•
Equivalence trial: An RCT which compares two active agents. Equi
-
valence trials often compare new treatments to usual (standard) care,
and may not include a placebo arm.
•
Before and after comparison: A study that reports only the change
in outcome in each group of a study, and does not report between-
group comparisons. This is a common error in studies that claim to
be RCTs.
•
Case series: A description of a group of patients with a condition,
treatment, or outcome (e.g., 20 patients with migraine headache
underwent acupuncture and 17 reported feeling better afterwards).
Case series are considered weak evidence of efficacy.
•
Case-control study: A study in which patients with a certain out-
come are selected and compared to similar patients (without the out-
come) to see if certain risk factors/predictors are more common in
patients with that outcome. This study design is not common in the
complementary and alternative medicine literature.
•
Cohort study: A study which assembles a group of patients with
certain baseline characteristics (e.g., use of a drug), and follows
them forward in time for outcomes. This study design is not com-
mon in the complementary and alternative medicine literature.
•
Meta-analysis: A pooling of multiple trials to increase statistical
power (often used to pool data from a number of RCTs with small
sample sizes, none which demonstrates significance alone but in
aggregate can achieve significance). Multiple difficulties are en
-
countered when designing/reviewing these analyses; in particular,
outcomes measures or therapies may differ from study to study,
hindering direct comparison.
•
Review: An author’s description of his or her opinion based on per
-
sonal, non-systematic review of the evidence.
•
Systematic review: A review conducted according to pre-specified
criteria in an attempt to limit bias from the investigators. System
-
atic reviews often include a meta-analysis of data from the in
-
cluded studies.
•
P: Pending verification.
108 JOURNAL OF HERBAL PHARMACOTHERAPY

Author, Year
Identifies the study being described in a row of the table.
N
The total number of subjects included in a study (treatment group plus
placebo group). Some studies recruit a larger number of subjects initially,
but do not use them all because they do not meet the study’s entry criteria.
In this case, it is the second, smaller number that qualifies as N. N in
-
cludes all subjects that are part of a study at the start date, even if they
drop out, are lost to follow-up, or are deemed unsuitable for analysis
by the authors. Trials with a large number of drop-outs that are not in-
cluded in the analysis are considered to be weaker evidence for efficacy.
(For systematic reviews the number of studies included is reported.
For meta-analyses, the number of total subjects included in the analysis
or the number of studies may be reported.) P = pending verification.
Statistically Significant?
Results are noted as being statistically significant if a study’s authors
report statistical significance, or if quantitative evidence of significance
is present (such as p values). P = pending verification.
Quality of Study
A numerical score between 0 and 5 is assigned as a rough measure of
study design/reporting quality (0 being Weakest and 5 being Strongest).
This number is based on a well-established, validated scale developed
by Jadad et al. (Jadad AR, Moore RA, Carroll D, et al. Assessing the
quality of reports of randomized clinical trials: Is blinding necessary?
Controlled Clinical Trials 1996;17[1]:1-12.) This calculation does not
account for all study elements that may be used to assess quality (other
aspects of study design/reporting are addressed in the “Evidence Dis
-
cussion” sections of reviews).
•
A Jadad score is calculated using the seven items in the following
table. The first five items are indications of good quality, and each
counts as one point towards an overall quality score. The final two
items indicate poor quality, and a point is subtracted for each if its
criteria are met. The range of possible scores is 0-5.
Natural Standard Review 109

Magnitude of Benefit
This summarizes how strong a benefit is: small, medium, large,
or none. If results are not statistically significant “NA” for “not applica-
ble” is entered. In order to be consistent in defining small, medium, and
large benefits across different studies and reviews, Natural Standard
defines the magnitude of benefit in terms of the standard deviation (SD)
of the outcome measure. Specifically, the benefit is considered
•
Large: if > 1 SD
•
Medium: if 0.5 to 0.9 SD
•
Small: if 0.2 to 0.4 SD
•
P = Pending verification.
In many cases, studies do not report the standard deviation of change
of the outcome measure. However, the change in the standard devia
-
tion of the outcome measure (also known as effect size) can be calcu
-
lated, and is derived by subtracting the mean (or mean difference) in the
placebo/control group from the mean (or mean difference) in the treat
-
ment group, and dividing that quantity by the pooled standard devia
-
tion (Effect size = [Mean Treatment ⫺ Mean Placebo]/SDp).
Absolute Risk Reduction
This describes the difference between the percent of people in the
control/placebo group experiencing a specific outcome (control event
110 JOURNAL OF HERBAL PHARMACOTHERAPY
Jadad Score Calculation
Item Score
Was the study described as randomized (this includes words such as randomly, random, and
randomization)?
0/1
Was the method used to generate the sequence of randomization described and appropriate
(table of random numbers, computer-generated, etc.)?
0/1
Was the study described as double blind? 0/1
Was the method of double blinding described and appropriate (identical placebo, active
placebo, dummy, etc.)?
0/1
Was there a description of withdrawals and dropouts? 0/1
Deduct one point if the method used to generate the sequence of randomization was described
and it was inappropriate (patients were allocated alternately, or according to date of birth,
hospital number, etc.).
0/–1
Deduct one point if the study was described as double blind but the method of blinding was
inappropriate (e.g., comparison of tablet vs. injection with no double dummy).
0/–1

rate), and the percent of people in the experimental/therapy group
experiencing that same outcome (experimental event rate). Mathemati
-
cally, Absolute risk reduction (ARR) equals experimental event rate mi
-
nus control event rate. ARR is better able to discriminate between large
and small treatment effects than relative risk reduction (RRR), a calcu
-
lation that is often cited in studies ([control event rate-experimental
event rate]/control event rate). Many studies do not include adequate
data to calculate the ARR, in which cases “NA” is entered into this
column. P = pending verification.
Number Needed to Treat
This is the number of patients who would need to use the therapy un-
der investigation, for the period of time described in the study, in order
for one person to experience the specified benefit. It is calculated by di-
viding the Absolute Risk Reduction into 1 (1/ARR); P = Pending
verification.
Comments
When appropriate, this section may comment on design flaws (inade-
quately described subjects, lack of blinding, brief follow-up, no intention
to treat, etc.), notable study design elements (crossover, etc.), dosing,
and/or specifics of study group/sub-groups (age, gender, etc). More de-
tailed description of studies is found in the “Evidence Discussion” sec-
tion that follows the “Evidence Table” in Natural Standard reviews.
EVIDENCE DISCUSSION
Diabetes
Summary: Preliminary data from one small randomized controlled
trial investigating the effects of banaba on diabetes report promising re
-
sults. However, due to the small sample size and short study duration,
this study can only be considered investigative in nature, not definitive.
Additional research is necessary before a firm conclusion can be made.
Evidence: Judy et al. conducted a randomized controlled trial to in
-
vestigate the antidiabetic activity of an extract from the leaves of Lager
-
stroemia speciosa, standardized to 1% corosolic acid (Glucosol
TM
),
Natural Standard Review 111

involving patients with Type II diabetes (non-insulin-dependent diabe
-
tes mellitus, NIDDM) (2). In this dose-response study, 10 subjects were
randomly divided into two groups. Five subjects in each group received
a daily oral dose for 15 days of either a soft gelatin or hard gelatin for
-
mulation of 16, 32, and 48 mg Glucosol
TM
sequentially with a 10-day
washout period in between doses. Blood glucose levels were measured.
Both soft gel and hard gel formulations of Glucosol
TM
showed a drop in
blood glucose level over the dose range of 16-48 mg per day (which
translates to a daily dose of 0.16-0.48 mg of corosolic acid). Glucosol
TM
at daily dosages of 32 and 48 mg for two weeks showed a significant re
-
duction in the blood glucose levels. Glucosol
TM
in a soft gel capsule for-
mulation showed a 30% decrease in blood glucose levels compared to
a 20% drop seen with dry-powder filled hard gelatin capsule formula-
tion (p < 0.001), suggesting that the soft gel formulation has a better bio-
availability than a dry-powder formulation. However, due to small
sample size and short duration, its results can only be considered
exploratory.
PRODUCTS STUDIED
Brands Used in Clinical Trials
Glucosol
TM
(Soft Gel technologies, Los Angeles CA).
2
Brands Shown to Contain Claimed Ingredients
Through Third-Party Testing
Not applicable.
REFERENCES
1. Murakami, C., Myoga, K., Kasai, R., Ohtani, K., Kurokawa, T., Ishibashi, S.,
Dayrit, F., Padolina, W. G., and Yamasaki, K. Screening of plant constituents for effect
on glucose transport activity in Ehrlich ascites tumour cells. Chem Pharm Bull. (To
-
kyo) 1993;41(12):2129-2131.
2. Judy, W. V., Hari, S. P., Stogsdill, W. W., Judy, J. S., Naguib, Y. M., and
Passwater, R. Antidiabetic activity of a standardized extract (Glucosol) from Lager
-
stroemia speciosa leaves in Type II diabetics. A dose-dependence study. J Ethno
-
pharmacol. 2003;87(1):115-117.
112 JOURNAL OF HERBAL PHARMACOTHERAPY

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and quantitative analysis of the alpha-amylase inhibitor in Lagerstroemia speciosa (L.)
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4. Suzuki, Y., Unno, T., Ushitani, M., Hayashi, K., and Kakuda, T. Antiobesity ac
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tivity of extracts from Lagerstroemia speciosa L. leaves on female KK-Ay mice. J Nutr
Sci Vitaminol. (Tokyo) 1999;45(6):791-795.
5. Garcia, L. L., et al. Pharmaceutico-chemical and pharmacological studies on a
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and Howard, Miles D. Antithrombin activity of medicinal plants from central Florida. J
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7. Hattori, K., Sukenobu, N., Sasaki, T., Takasuga, S., Hayashi, T., Kasai, R.,
Yamasaki, K., and Hazeki, O. Activation of insulin receptors by lagerstroemin. J
Pharmacol Sci. 2003;93(1):69-73.
8. Unno, T., Sugimoto, A., and Kakuda, T. Xanthine oxidase inhibitors from the
leaves of Lagerstroemia speciosa (L.) Pers. J Ethnopharmacol. 2004;93(2-3):391-395.
9. Matsuura, T., Yoshikawa, Y., Masui, H., and Sano, M. Suppression of glucose
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2004;124(4):217-223.
10. Hong, H. and Jai, Maeng W. Effects of malted barley extract and banaba extract
on blood glucose levels in genetically diabetic mice. J Med Food 2004;7(4):487-490.
11. Hayashi, T., Maruyama, H., Kasai, R., Hattori, K., Takasuga, S., Hazeki, O.,
Yamasaki, K., and Tanaka, T. Ellagitannins from Lagerstroemia speciosa as activators
of glucose transport in fat cells. Planta Med 2002;68(2):173-175.
12. Kakuda, T., Sakane, I., Takihara, T., Ozaki, Y., Takeuchi, H., and Kuroyanagi,
M. Hypoglycemic effect of extracts from Lagerstroemia speciosa L. leaves in geneti-
cally diabetic KK-AY mice. Biosci Biotechnol Biochem. 1996;60(2):204-208.
doi:10.1300/J157v07n01_09
Natural Standard Review 113