Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-inflammatory activity

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https://www.heighpubs.org/hps 089
https://doi.org/10.29328/journal.apps.1001019
Abstract
Background: Combination of extracts from multiple plants are typically used in ethnomedicine
to putatively offer more potent chemotherapeutic and chemopreventive effects than that
of individual extracts from single plants. Aqueous extracts from two multipurpose plants
Strophanthus hispidus (roots) and Aframomum meleguta (seeds) are topically co-administered in
the nasal cavities for the ethnomedicinal management of chronic sinusitis.
Aim: This study assessed the potential phytochemical synergy between constituent extracts
of Strophanthus hispidus (roots) and Aframomum meleguta (seeds) in its anti-infl ammation, anti-
microbial and anti-oxidant effects.
Methods and Materials: Broth dilution assay assessed anti-microbial activities. DPPH radical
scavenging assay examined the scope of anti-oxidant activities and inhibition of carrageenan-
induced 7-day old chick feet oedema revealed anti-infl ammatory activities.
Results: Anti-microbial activities of individual plant extracts in broth dilution assay showed
comparable potency to that of the co-extract mixture. Similarly, individual extracts showed levels
of DPPH radical scavenging activities in anti-oxidant assay that was comparable to those found
for the co-extract mixture. In contrast to these two effects, inhibition of carrageenan-induced 7-day
old chick feet oedema revealed an anti-infl ammatory activity evoked by co-extract mixtures that
was greater than the sum of the individual potencies of the two extracts.
Conclusion: The potential phytochemical synergy of the two plants extracts in its anti-
infl ammatory response largely validates ethnomedicinal practice and generally confi rms growing
literature reports that ascribe the net pharmacological activities of herbal extracts to the combined
multi-activities of unique phytochemical entities at multiple target sites.
Research Article
Co-extract mixture from Strophanthus
hispidus (roots) and Aframomum
meleguta (seeds) show phytochemical
synergy in its anti-infl ammatory activity
John Kenneth Mensah1*, Amina Ibrahim1 and Yakubu Jibira2
1Department of Chemistry, Kwame Nkrumah University of Science and Technology (KNUST),
Kumasi, Ghana
2Department of Pharmacognosy, Faculty of Pharmacy & Pharmaceutical Sciences, College of Health
Sciences, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
Introduction
Ethnomedicinal-based management of many diseases
often rely on concoctions of multiple plant extracts mixed in
permissive co-extract ratios that exploits the unique biological
activities of distinct phytochemical pools through additive or
synergistic interactions [1-5]. Aqueous extracts from the two
botanicals Strophanthus hispidus (roots) and Aframomum
meleguta (seeds) has represented a local example of this
approach since antiquity and their simultaneous topical
co-administration offers effective chemopreventive and
chemotherapeutic ethnomedicinal strategy against chronic
sinusitis.
Chronic sinusitis is an airway disease characterized
by persistent inlammation and microbial infection of the
nasal and sinus mucosa. The condition has a prolonged
clinical course and many of its current treatment modalities,
including conventional medical and surgical therapies are
largely ineffective. The observation of an eficacious multi-
plant extract ethnomedicinal remedy for chronic sinusitis
suggested the possibility that the total pool of extract
More Information
*Address for Correspondence: John Kenneth
Mensah, Department of Chemistry, Kwame
Nkrumah University of Science and Technology
(KNUST), Kumasi, Ghana, Tel: +233 200 693323;
Email: jkmensah.cos@knust.edu.gh
Submitted: 29 November 2019
Approved: 10 December 2019
Published: 11 December 2019
How to cite this article: Mensah JK, Ibrahim A,
Jibira Y. Co-extract mixture from Strophanthus
hispidus (roots) and Aframomum meleguta
(seeds) show phytochemical synergy in its anti-
infl ammatory activity. Arch Pharm Pharma Sci.
2019; 3: 089-100.
DOI: dx.doi.org/10.29328/journal.apps.1001019
ORCiD: orcid.org/0000-0002-1232-7217
Copyright: © 2019 Mensah JK, et al. This is
an open access article distributed under the
Creative Commons Attribution License, which
permits unrestricted use, distribution, and re-
production in any medium, provided the original
work is properly cited.
Keywords: Strophanthus hispidus; Aframomum
meleguta; Anti-microbial; Anti-oxidant; Anti-
infl ammation
OPEN ACCESS

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
activity
https://www.heighpubs.org/hps 090
https://doi.org/10.29328/journal.apps.1001019
phytochemicals from the combined Strophanthus hispidus
(roots) and Aframomum meleguta (seeds) extracts interact
functionally to produce either additive or synergistic
chemopreventive and chemotherapeutic effects that may
be anti-microbial, anti-oxidant and anti-inlammatory [6].
Therefore, the central hypothesis underlying this work is
that extract phytochemicals derived from Strophanthus
hispidus (roots) and Aframomum meleguta (seeds) function in
biochemical synergy to confer anti-microbial, anti-oxidant and
anti-inlammatory effects. This key hypothesis that potential
phytochemical synergy between constituent extract account
for its robust effect against chronic sinusitis was therefore
examined by the experimental assessment of the anti-
microbial, anti-oxidant and anti-inlammation bioactivities of
both individual extracts and co-extract mixture.
Both Strophanthus hispidus (roots) and Aframomum
meleguta (seeds) are botanicals endogenous to the tropical
Africa and each plant inds extensive use, alone or in
combination with other plants, in prevalent ethnomedicinal
cultures of several African states [4,7-13]. Both Strophanthus
hispidus (roots) and Aframomum meleguta (seeds) have been
systematically lab-tested for anti-microbial, anti-oxidant
and anti-inlammatory effectiveness [7-13]. However, the
possible synergistic or additive response that is evoked
in their phytochemical bioactivities when combined in
ethnomedicinal remedy has not been scientiically elucidated.
Consequently, there is little current evidential scientiic
support for the historical and enduring ethnomedicinal
utilization of the combined extracts of Strophanthus hispidus
(roots) and Aframomum meleguta (seeds) for the clinical
management of chronic sinusitis.
Using this ethnomedicinal knowledge base as pharmaco-
logical support and the methanol extracts of
both plants
as phytochemicals sources, this study presents evidence
indicative of synergistic interaction of Strophanthus hispidus
(roots) and Aframomum meleguta (seeds) phytochemicals
to the anti-inlammation activities of the co-extract. The
study shows that co-administered topically, co-extract
phytochemicals inhibit microbial growth, scavenge free
radicals and their complementary physiological effects
synergizes to inhibit inlammation. Taken together, the
results indicate that co-extract anti-inlammatory bioactivity
may derive from functional synergism between the
phytochemical pools of the two plant extracts. Interestingly,
this synergistic effect was not observed for the anti-microbial
and anti-oxidant bioactivities.
Although the exact mechanistic action and mechanistic
targets of individual extract phytochemicals are unknown,
evidence from this study suggests that the ethnomedicinal
application of the co-extracts in the management of sinusitis
may have scientiic merit. This study ills an important
mechanistic void in ethnomedicine with its suggestion of a
synergistic induction of in vivo anti-inlammation activity
by phytochemical combinations from Strophanthus hispidus
(roots) and Aframomum meleguta (seeds).
Materials and Methods
Extracts of Strophanthus hispidus (roots) and Aframomum
meleguta (seeds) were individually examined for anti-
microbial, anti-oxidant and anti-inlammatory effects and
then aliquots of both extracts blended in a 3:2 (weight/
weight) ratio as the co-extract synergy mixture was
similarly assessed for anti-microbial, anti-oxidant and anti-
inlammatory effects.
Plant materials
Strophanthus hispidus (roots) and Aframomum
meleguta (seeds) were selected for this study because of
their historically high use prevalence and their reputed
ethnomedicinal eficacy. Plant specimens were purchased
in the local market and purchased plants were veriied in
terms of genus and species at the Department of Biology of
KNUST. Voucher plant specimens were retained at the school
of Pharmacy of KNUST.
Soxhlet extraction
Methanol extracts of (Strophanthus hispidus (roots) and
Aframomum meleguta (seeds) were obtained by Soxhlet
extraction as previously described [14]. Extracts were
concentrated on a rotavap and the resulting residue stored
at -20 ˚C until needed. Stock solutions of 20 mg/mL of
(Strophanthus hispidus (roots) extract and of Aframomum
meleguta (seeds) extract were prepared in 99% methanol
and diluted as needed for different assays. Diluted extracts
solutions were ilter sterilized before use.
Regional or geographical differences in plant location,
subtle genotypic differences in plant genomes as well as
seasonal harvest differences in plant phytochemical content
are known to affect the chemotype and the quantity of extract
phytochemicals. Consequently, experimental extracts could
not be standardized with any known reference standard.
Neither the acute nor the chronic toxicity of extracts were
examined in this study.
TLC
Silica gel thin-layer chromatography (TLC) was employed
to estimate the approximate number of distinct chemical
entities within each extract. Briely, a small sample of the
stock extract solutions were dissolved in 1 mL methanol and
spotted on an in-house prepared 10 cm by 5 cm and 0.2 mm
thick silica gel plate as previously described [14]. Developing
solvent system utilized for the separation of constituents
was ethyl acetate and petroleum ether in a 4:1 ratio. Iodine
vapor visualization of resolved chromatographic bands and
calculation of Rf values of constituent bands were performed
as described earlier [14].

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
activity
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https://doi.org/10.29328/journal.apps.1001019
Phytochemical analyses
Phytochemical composition of each crude extracts was
assessed using slight modiications of the methods of Trease
and Evans [15] as previously described [16].
Synergy extract mixture and synergy studies
To assess the potential phytochemical synergy in
inhibitory effects toward microbial growth, ROS production
and inlammation, a 3:2 (weight/weight) Strophanthus
hispidus (roots): Aframomum meleguta (seeds) extracts ratio
was used. Pegging of the co-extract synergy mixture ratio at
3:2 (weight/weight) was based on best practices guidelines
observed by local herbalists who rely on the phytochemical
mixture of the two botanicals for the ethnomedicinal
management of sinusitis. Utilization of this weight ratio
implies that inal co-extract concentrations possesses
reduced individual extracts concentrations relative to that of
either extract alone.
Synergy studies
The prevailing hypothesis undergirding this work was
that combined extract phytochemicals from (Strophanthus
hispidus (roots) and Aframomum meleguta (seeds) will
produce synergistic activity. Potential functional synergism
by co-extract phytochemicals will be observed through
quantitative differences in their molecular actions in anti-
microbial, anti-oxidant and anti-inlammatory assays.
Consequently, individual extracts were irst examined
singly and then in a combination maintained at the 3:2
(Strophanthus hispidus (roots) and Aframomum meleguta
(seeds) (w/w) ratio. Synergy was quantitatively taken to be
the bioactivity of the co-extract mixture that was greater than
the sum of the individual bioactivity of either extract alone
while antagonism was deined as the co-extract bioactivity
that was lower than the sum of individual bioactivity of each
extract.
Anti-infl ammatory assay
The Carrageenan-induced foot oedema in 7-day old chick
model was used for the assessment of the anti-inlammatory
effects of extracts and of the co-extract synergy mixture.
Chicks were randomly divided into groups of ive and
a 1% suspension of carrageenan in distilled water was
administered as 0.1 ml subplantar injection into the footpad
of the right foot as previously described [14]. Chicks were
then treated intraperitoneally with vehicle or with extracts
(30, 100, 300 mg/kg body weight) or with co-extracts (3, 10
mg/kg body weight) in vehicle. The negative control animals
received only the vehicle while a positive control group
received reference drugs dexamethasone (0.3, 1, and 3 mg/
kg body weight) and diclofenac (10, 30, and 100 mg/kg body
weight). Foot volumes were checked before carrageenan
injection and at hourly intervals for ive hours as described
[14]. Oedema volumes were determined as the difference
between the foot volumes of each chick before carrageenan
injection and the foot volumes at the hourly time intervals.
Data analysis utilized a one-way analysis of variance and
differences between groups of chicks analyzed by Bonferroni’s
modiied t test. A p value of 0.05 was considered signiicant.
Extract or control drug treatment-mediated decreases in the
volumes of oedema were utilized as a quantitative measure
of the anti-inlammatory response. Post-treatment hourly
estimated oedematous volumes was used as a graphical time
course representation of anti-inlammatory response. The
overall anti-inlammatory effect of each tested extract was
presented as net anti-inlammatory effect. Sample ED50 were
computed with linear regression as previously reported [14].
DPPH radical scavenging assay
To examine the anti-oxidant eficacy of the extracts and of
the synergy co-extract, use was made of the well-established
free radical scavenging assay that employs DPPH as a radical
scavenger. Prior description of the experimental method is
provided [14]. Radical scavenging activity of test samples are
presented in a dose-response curve that shows % inhibition
versus concentration of samples. Estimation of sample EC50
was accomplished through linear regression analysis. A
triplicate test for each sample concentration presents each
sample point as a Mean ± SD.
Total phenolic content by Folin-Ciocalteu method
Estimation of the total phenolic contents of the extracts
and of the co-extract synergy mixture was performed
using the Folin-Ciocalteu reagent with protocols published
elsewhere [14]. Interpolation from the standard Gallic Acid
curve provided total phenolic contents of samples in Gallic
Acid equivalents (GAE). A triplicate test for each sample
concentration presents each sample point as a Mean ± SD.
Microbial panel
The genotypes and sources of microbial strains used in
this study have previously been described [14,16]. A panel
of 5 pathogenic microbial specimen that included 2 gram-
positive bacteria (Streptococcus pyogenes, Staphylococcus
aureus), 2 gram negative bacteria (Pseudomonas aeruginosa,
Escherichia Coli) and a fungi (Candida albicans) were used as
microbial targets for the assessment of extract and co-extract
anti-microbial eficacy.
Earlier reports have described the genotype, storage,
culture and maintenance of these microbes [16]. Working
cultures of each microbe was maintained at 106 CFU/mL
using McFarland standard as previously described [16].
Broth dilution assay
Extracts and synergy co-extract were tested for growth
inhibitory activity against the panel of 5 pathogenic microbes
using the Broth Dilution Anti-microbial Assay as previously

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
activity
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https://doi.org/10.29328/journal.apps.1001019
described [14,16]. Pathogenic microbes were cultured as
described [16] and split into three sets of identical cultures
with each tube of cells containing 106 CFU/mL. One set
was treated with Strophanthus hispidus (roots) extract
while another was treated with Aframomum meleguta
(seeds) extract. The third set of microbial culture received
the combined Strophanthus hispidus (roots): Aframomum
meleguta (seeds) co-extract treatment.
The same range of sample concentrations were utilized
for pathogenic microbiocidal sensitivity: (Strophanthus
hispidus (roots) extract alone (0.09 –12.5 mg/mL),
Aframomum meleguta (seeds) extract alone (0.09–12.5
mg/mL) and co-extract synergy mixture maintained at 3:2
w/w ratio of Strophanthus hispidus (roots) and Aframomum
meleguta (seeds) (0.09–12.5 mg/mL). Pharmaceutical drugs
ciproloxacin (anti-bacteria agent) and luconazole (anti-
fungal agent) were utilized as positive controls. Uninoculated
sterile broth media with and without extracts were utilized
as negative controls. Minimum Inhibitory Concentrations
(MICs) were taken as the lowest extract concentration that
yielded complete microbial growth inhibition.
Statistical analysis
Experiments were repeated and each sample point
analyses performed in triplicates. Mean and the Standard
Deviation of experimental replicates were computed with
Microsoft Excel XP.
Results
TLC
TLC demonstration that each plant extract comprise
multiple chemical entities is in line with the observed varied
phytochemical compositions for each extract. The three
observable TLC bands for Strophanthus hispidus (roots)
extract and the two discernible bands for Aframomum
meleguta (seeds) extract (Table 1) are on the lower scale of
chemical entities present in a crude extract and the problem
might be due to the lower separatory eficiencies of the
utilized chromatographic method. Nevertheless, Rf values in
table 1 show that all chromatographic bands were reasonably
well-resolved.
Phytochemical characterizations of extracts
Strophanthus hispidus (roots) extract is richly endowed
with an array of potentially bioactive phytochemical
chemotypes including saponins, lavonoids and
alkaloids (Table 1). Aframomum meleguta (seeds) is also
phytochemical-rich, endowed with glycosides, carotenoids
and anthraquinones (Table 1). Phytochemical groups in both
extracts are functionally known to evoke diverse bioactivities
in chemopreventive and chemotherapeutic mechanisms
including those of anti-microbial, anti-oxidant and anti-
inlammatory activities. Despite the disparate plant parts
(roots and seeds) and distinct plant species, Strophanthus
hispidus (roots) and Aframomum meleguta (seeds) extracts
showed striking details in similarities in phytochemical
compositions (Table 1).
Ratio of individual extracts in co-extract mixture
A 3-to-2 weight/weight ratio of Strophanthus hispidus
(roots) to Aframomum meleguta (seeds) derived from the
best ethnomedicinal practices and guidelines was utilized
for all concentrations of the co-extract in all assays (anti-
inlammation, anti-microbial and anti-oxidant) as stated in
Materials and Methods. Maintenance of this ratio for all co-
extract concentration treatment implies that in some cases,
co-extract mixtures contain reduced individual extracts
concentrations relative to concentrations of either extract
alone.
Anti-microbial activities
Microbial colonization of the sinus-nasal cavity plays an
etiologic role in the pathophysiology of sinusitis. To assess
the microbiocidal eficacy of individual Strophanthus hispidus
(roots) and Aframomum meleguta (seeds) extracts and to
further examine the possible synergistic anti-microbial
effects of the Strophanthus hispidus (roots)-Aframomum
meleguta (seeds) co-extract mixture, different doses of test
samples were evaluated for relative growth inhibitory effects
on a panel of 5 pathogenic microbes using Broth Dilution
assay.
Bactericidal eficacies of extracts and of co-extract differed
by target microorganism as shown, in quantitative terms, by
the widely differing pathogen-speciic range of extract MICs.
The gram positive bacteria Streptococcus pyogenes showed
the highest sensitivity to Strophanthus hispidus extract,
succumbing to its bactericidal activities at a low MIC of 0.78
mg/mL (Tables 2- 4). The data shows no preferential display
of sensitivity to the anti-proliferative effects of Strophanthus
hispidus by the gram positive bacteria. Staphylococcus
aureus, the other gram positive bacteria strains was the
least sensitive pathogenic bacteria to Strophanthus hispidus
extract’s anti-proliferative activities. Staphylococcus aureus
displayed weak sensitivity with an 8-fold increase in the MIC
of Streptococcus pyogenes. Strophanthus hispidus showed a
reduced anti-proliferative effect on the two gram-negative
bacteria strains. MICs of Strophanthus hispidus extract
against the gram-negative Escherichia coli were comparable
Table 1: Thin layer chromatography (TLC) and phytochemical contents report of
methanolic extracts of SH Strophanthus hispidus and of AM Aframomum melegueta
plant samples.
Sample
TLC Results
Phytochemicals Present
Number of spots
from TLC and Rf
values
Strophanthus
hispidus
Three
0.07, 0.19, 0.37
Saponins, Flavonoids, Cyanogenetic
glycosides, alkaloids, Carotenoids,
Anthraquinone glycosides
Aframomum
melegueta
Two
0.14, 0.31
Saponins, General glycosides, Flavonoids,
Cyanogenetic glycosides, Alkaloids,
Carotenoids, Anthraquinones

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
activity
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to those recorded against the gram-negative Pseudomonas
aeruginosa. Both Pseudomonas aeruginosa and Escherichia
coli showed sensitivity considered intermediate at an MIC of
3.12 mg/mL (Tables 2-4).
Aframomum meleguta extract demonstrated relatively
good eficacy against the two gram-negative bacteria
(Pseudomonas aeruginosa and Escherichia coli), as both
yielded strongly to its antimicrobial activity at a low MIC
of 0.78 mg/mL (Tables 2-4). Growth inhibitory effects
of Aframomum meleguta extract on gram positives
Streptococcus pyogenes and Staphylococcus aureus were
also high. Aframomum meleguta extract yielded an elevated
level of anti-proliferative activity with an MIC of 0.39 mg/
mL on Staphylococcus aureus. Slightly lower (a 2-fold
difference lower MIC) growth inhibitory activity was evoked
by Aframomum meleguta against Streptococcus pyogenes
(MIC of 1.56 mg/mL). Taken together, Aframomum meleguta
extract was comparatively more effective in suppressing
bacteria growth as it displayed a much broader range of
eficacious growth inhibition against the 4 bacteria species in
the panel of 5 micro-organisms.
Microbiocidal activities of the co-extract mixture
against the same pathogenic microbes were mostly marked
by higher MICs, or at best, by MIC values comparable to
those obtained for individual extracts. For Streptococcus
pyogenes, increases in MIC of the individual extracts up to
4-fold (for Aframomum meleguta alone) and up to 6-fold
(for Strophanthus hispidus alone) were observed for the co-
extract (Tables 2-4). MICs of co-extract required to inhibit
Escherichia coli and Staphylococcus aureus proliferation
was similarly double the quantitative value of that evoked
by Aframomum meleguta extract alone: MIC values for co-
extract were 1.56 mg/mL for Escherichia coli and 0.78 mg/
mL for Staphylococcus aureus whereas the corresponding
MIC values for Aframomum meleguta extract alone were 0.78,
0.39 mg/mL respectively (Tables 2-4). With Pseudomonas
aeruginosa, anti-proliferative potencies of co-extract were
comparable to those of Aframomum meleguta extract alone
(MIC of 0.78 mg/mL) (Tables 2-4).
Differences in the potency of the bactericidal actions of
Aframomum meleguta extract alone or of the Strophanthus
hispidus extract alone or of their co-extract were observed to
be signiicant for Staphylococcus aureus. With Staphylococcus
aureus, MICs were approximately 16-fold lower with
Aframomum meleguta extract than it was with Strophanthus
hispidus extract. The co-extract evoked growth inhibition of
Staphylococcus aureus at an approximately 2-fold lower MIC
relative to that of Aframomum meleguta extract. Aframomum
meleguta extract showed the strongest and broadest
inhibitory activities against all bacteria with Staphylococcus
aureus as the most signiicantly affected. With Pseudomonas
aeruginosa and at MIC up to 3.12 mg/mL, Strophanthus
hispidus extract showed low anti-proliferative activity.
Evaluated across all three test extract samples, Pseudomonas
aeruginosa can be considered the most sensitive bacteria
among the panel because it succumbed to the bactericidal
activities of all extract and of co-extracts at relatively low
MICs (3.12 for Strophanthus hispidus; 0.78 for Aframomum
meleguta and 0.78 for the co-extract mixture) (Tables 2-4).
Anti-fungal activities of extract phytochemicals were
uniformly poor across the three test extract samples.
Aframomum meleguta extracts did not detectably inhibit
the proliferation of Candida albicans. Candida albicans was
also the microorganism that was the least susceptible to the
suppressive growth effects evoked by Strophanthus hispidus
extract as inhibition was inally achieved at a higher MIC
of 6.25 mg/mL. Co-extract fungicidal activities on Candida
albicans were 2-fold difference lower than that evoked
by Strophanthus hispidus extract alone (occurring at an
unusually high MIC of 12.5 mg/mL) (Tables 2-4).
Table 2: Broth dilution showing MICs for methanolic extracts of Strophanthus
hispidus, Aframomum melegueta and for the co-extract mixture.
Sample Test Organisms Concentrations (mg/ml)
12.5 6.25 3.12 1.56 0.78 0.39 0.19 0.09
Strophanthus
hispidus
Aframomum
melegueta
Co-extract
Mixture
P. aeruginosa
S. pyogenes
E. coli
S. aureus
C. albicans
-
-
-
-
-
-
-
-
-
-
-
-
-
+
+
+
-
+
+
+
+
-
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
P. aeruginosa
S. pyogenes
E. coli
S. aureus
C. albicans
12.5 6.25 3.12 1.56 0.78 0.39 0.19 0.09
-
-
-
-
+
-
-
-
-
+
-
-
-
-
+
-
-
-
-
+
-
+
-
-
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
P. aeruginosa
S. pyogenes
E. coli
S. aureus
C. albicans
12.5 6.25 3.12 1.56 0.78 0.39 0.19 0.09
-
-
-
-
-
-
-
-
-
+
-
+
-
-
+
-
+
-
-
+
-
+
+
-
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+ indicates microbial growth; - indicates no microbial growth
Table 3: Broth dilution showing MICs for standard drugs (Ciprofl oxacin and
Fluconazole) used as positive control.
Standard Test
Organisms
Concentration (μg/ml)
12.5 6.25 3.12 1.56 0.78 0.39 0.19 0.09
Ciprofl oxacin P. aeruginosa -------+
S. pyogens -------+
E. coli ------++
S. aureus -------+
100 50 25 12.5 6.25 3.12 1.56 0.78
Fluconazole C. albicans -------+
+ indicates microbial growth; - indicates no microbial growth
Table 4: Summary of MIC values of extracts and of the co-extract mixture and
control drugs recorded against test organisms.
Test Organisms MIC (mg/ml) MIC (μg/ml)
SH AM MIX Ciprofl oxacin Fluconazole
P. aeruginosa 3.12 0.78 0.78 0.19
S. pyogens 0.78 1.56 6.25 0.19
E. coli 3.12 0.78 1.56 0.39
S. aureus 6.25 0.39 0.78 0.19
C. albican 6.25 - 12.5 0.78
SH: Strophanthus Hispidus; AM: Aframomum Melegueta; MIX: Co-extract Mixture

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
activity
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MICs for extract-treated microbial strains were higher
(at best about 2-fold difference higher) than that of positive
controls drug (Ciproloxacin and luconazole) indicating
weaker relative anti-microbial activities of the extracts and
of the co-extract mixture (Table 4).
No synergy in anti-microbial activities
The data strongly suggests that the anti-microbial eficacy
of Strophanthus hispidus extract was not enhanced by the
addition of Aframomum meleguta extract nor was that of
Aframomum meleguta extract improved in the co-extract
mixture by the added Strophanthus hispidus extract. Although
microbial susceptibility to microbiocidal effects of co-extract
mixtures differed according to species, attainable MICs
were at best comparable to that of individual extracts. Even
higher co-extract MICs were observed for some pathogenic
microbes suggesting that the co-extract does not exert a
synergistic anti-microbial response against this examined
panel of pathogenic microbes.
Anti-Oxidant activities
Reactive oxygen species (ROS)-mediated oxidative stress
trigger inlammation in pathophysiological mechanisms
linked to the etiology of chronic sinusitis. To examine the
anti-oxidant eficacies of individual Strophanthus hispidus
(roots) and Aframomum meleguta (seeds) extracts and to
additionally assess whether functional synergism exists in
the anti-oxidant effects of the co-extract of Strophanthus
hispidus (roots) and Aframomum meleguta (seeds), the DPPH
radical scavenging assay was used.
Graphical depiction of this DPPH radical scavenging
eficacies highlights marginal differences in anti-oxidant
activities at lower individual extract and lower co-extract
concentrations (Figure 1). Differences in anti-oxidant
activities, however, become well-deined at slightly higher
extract concentrations where the relative scavenging
responses to doses of test samples were large and where
discrete quantitative DPPH scavenging values for test
samples diverged. At even higher sample concentrations,
DPPH scavenging activities reaches a plateau (Figure 1) and
extract-dependent quantitative variations in anti-oxidant
effect becomes indistinguishable.
As shown in table 5 IC50 values of test extracts were
competitive with that of the Ascorbic acid control. Aframomum
meleguta extract demonstrated the highest DPPH scavenging
eficacy while Strophanthus hispidus extract showed the least
eficacy (Figure 1 and Table 5).
Although the co-extract was a strong anti-oxidant with
an IC50 of 173.5 μg/mL, it still lagged in eficacy relative to
Aframomum meleguta (seeds) extract as judged by relative
IC50 values (Table 5) and as further assessed by the graphical
depiction of dose-response values in igure 1. Strophanthus
hispidus extract (IC50 = 969.1 μg/mL), on the other hand is a
5-fold difference less potent DPPH radical scavenger relative
to the co-extract mixture. Quantitatively, the IC50 value of the
co-extract is sandwiched between that of the two individual
Strophanthus hispidus and Aframomum meleguta extracts
and its relative median position effectively mirrors the trend
in Total Phenolic Content (Tables 5,6).
Total phenolic content of Aframomum meleguta
seed extracts (57.71 mg GAE/100 g) were about 3-fold
difference higher than that of Strophanthus hispidus root
extracts. The co-extract mixture, nominally, showed higher
phenolic content than Strophanthus hispidus extract alone
but displayed a lower phenolic content than Aframomum
meleguta extract alone. Taken together, the increasing trend
in total phenolic contents of test extracts largely mirrors the
increasing quantitative trends in observed DPPH scavenging
activities.
No synergy in anti-oxidant activities
Viewed through the lens of phytochemical interactions
within the co-extract mixtures, Strophanthus hispidus extract
depressed the scavenging eficacy of Aframomum meleguta
extract phytochemicals in the co-extract mixture as its IC50
in the individual extract reduced by 12-fold when mixed in
the co-extract. On the other hand, the addition boosted the
scavenging activities of Strophanthus hispidus extract as the
overall IC50 of the co-extract mixture increased by about a
5-fold difference when compared to that of the Strophanthus
hispidus extract alone. Co-extract mixtures evoked radical
DPPH ASSAY
-1 0 1 2 3 4
-50
0
50
100
150 Ascorbic acid
SH
AM
MIX
Log Concentrat ion g/ml
ytivitca gnignevacs lacidar HPPD %
P
Figure
1:
Graphical depiction of the DPPH radical scavenging effi cacies of the
methanolic extracts of Strophanthus hispidus, Aframomum meleguta and of the
co-extract mixture aligned with that of Ascorbic acid control. SH: Strophanthus
Hispidus; AM: Aframomum Melegueta; Co-extract Mixture(MIX).
Table 5: DPPH radical scavenging activities of methanolic extracts of Strophanthus
Hispidus, Aframomum Meleguta and Ascorbic acid and their estimated IC50s.
Sample IC50 μg/ml
Ascorbic acid 2.093
SH 969.1
AM 14.30
MIX 173.5
SH: Strophanthus Hispidus; AM: Aframomum Melegueta; MIX: Co-extract Mixture
Table 6: Total Phenolic Content of Strophanthus hispidus and Aframomum meleguta
(gGAE/100g).
Sample Phenolic Content (gGAE/100g)
SH 20.4
AM 57.71
MIX 38.57
SH: Strophanthus Hispidus; AM: Aframomum Melegueta; MIX: Co-extract Mixture

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
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scavenging activity that are comparable to that of the
individual extracts. Consequently, when assessed via IC50s
the co-extract mixture did not induce synergistic scavenging
of DPPH radicals in its in vitro anti-oxidant response.
Anti-infl ammation activities
Inlammation of the sinus-nasal mucosa is a hallmark
etiologic feature of chronic sinusitis. To examine whether
individual extracts and the co-extract mixture inhibit
inlammation, samples were assessed for their relative
eficacies to reduce the swelling induced by carrageenan
treatment of the foot of 7-day old chicks. Measured inhibition
in oedematous foot volume triggered by individual extracts
and by the co-extract mixture was taken as the direct
quantitative estimate of the anti-inlammatory effect of plant
phytochemicals as described in Material and Methods. Anti-
inlammatory responses of test samples were quantitatively
presented as a time-course event (Figures 2,3) and further
evaluated as a dose response outcome (Figures 4,5).
Time-course of infl ammation inhibition
Anti-inlammatory responses of individual extracts and
of the co-extract follows a graded continuum of eficacy that
varies with increasing post treatment (p.t.) time. Suppressive
effects of 300 mg/kg dose of Strophanthus hispidus (roots)
extract on carrageenan-induced swelling of chick feet
commences within 1 h after treatment (Figure 2(i)) and
reaches a peak of 35% inhibition after 3 h before it recedes
in magnitude to 10% after 5 h. The lower dose of 100 mg/
kg Strophanthus hispidus (roots) extract showed reduced
effectiveness against the swelling exhibiting a maximal 25%
reduction after 2 h and a 5% after 3 h before ending with
1% at the eventual completion of the experiment at 5 h. The
lowest dose (30 mg/kg) of Strophanthus hispidus (roots)
extract evoked a marginal anti-inlammatory response
SH (A)
0 2 4 6
-20
-10
0
10
20
30
40
Control
30
100
300
Time/hr
emulov toof ni esaercni%
AM ( A)
0 2 4 6
-20
0
20
40
Control
30
100
300
Time/hr
emulov toof ni esaercni%
MIXTURE (A)
0 2 4 6
-20
-10
0
10
20
30
40
Control
MIX A
MIX B
Time/hr
emulov toof ni esaercni%
iii
ii
Figure
2:
Time course of oedema volume changes in the carrageenan-induced
infl ammation of the 7-day chick foot triggered by individual Strophanthus
hispidus (SH) extract (i) and Aframomum melegueta (AM) extract (ii) and by the
Strophanthus hispidus-Aframomum melegueta co-extract mixture (MIX) (iii). Co-
extract induced inhibition in oedematous volume utilizes two different doses-3
mg/kg (MIX A) and 10 mg/kg (MIX B) of the mixture of extracts.
DICLOFENAC (A)
0 2 4 6
0
10
20
30
40
Control
10
30
100
Time/hr
emulov toof ni esaercni%
DEXAMETHASONE (A)
0 2 4 6
-20
0
20
40
60
Control
1
3
10
Time/hr
emulov toof ni esaercni%
Figure 3: Time course measurements of the anti-infl ammatory response of
Dexamethasone and Diclofenac on carrageenan-induced foot oedema in 7-day chicks.
SH (B)
control 30 100 300
0
50
100
150
mg/kg body weight
*** ***
*
CUA sa noitibihni amedeo %
AM (B)
control 30 100 300
0
50
100
150
mg/kg body weight
*** *** ***
CUA sa noitibihni amedeo %
MIXTURE (B)
control Mix A Mix B
0
50
100
150
mg/kg body weight
***
***
CUA sa noitibihni amedeo %
i.
ii.
iii.
Figure 4:
Dose-response of anti-infl ammatory activity evoked by individual
Strophanthus hispidus (SH) extract (i) and Aframomum melegueta (AM) extract
(ii) and by the Strophanthus hispidus-Aframomum melegueta co-extract mixture
(MIX) (iii) on the carrageenan-induced infl ammation of the 7-day chick foot. Co-
extract induced inhibition in oedematous volume utilizes two different doses-3
mg/kg (Mix A) and 10 mg/kg (Mix B) of the mixture of extracts. All test samples
(extracts and co-extract,) reduced oedema volumes in a dose-dependent manner
in the chick-feet carrageenan oedema assay. ***P < 0.001, **P < 0.01 and *P <
0.05 compared to the saline-treated group.
DEXAMETHASONE (B)
control 1 3 10
0
50
100
150
mg/kg body weight
*
*
CUA sa noitibihni amedeo %
DICLOFENAC (B)
control 10 30 100
0
50
100
150
mg/kg body weight
CUA sa noitibihni amedeo %
Figure 5:
Infl ammation suppressive effi cacy on the carrageenan-induced oedema
of the 7-day chick foot triggered by positive control drugs Dexamethasone and
Diclofenac. Control drugs reduced oedema volumes in a dose-dependent manner.

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
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that peaked at 15%, 2 h after ingestion. Beyond 2 h, anti-
inlammatory response per unit time for the 30 mg/kg dose
decreased signiicantly until completion of the experiment at
5 h.
Treatment with Aframomum meleguta (seeds) extract
reveals a time-course of inlammation inhibition qualitatively
identical to that of Strophanthus hispidus (roots) (Figure 2(ii)).
Anti-inlammation response initiated by the 300 mg/kg dose
of Aframomum meleguta (seeds) extract starts 1 h after extract
treatment and reaches a peak anti-inlammatory response
of 15% after 5 h. Chicken treated with the intermediate
dose of Aframomum meleguta (seeds) extracts (100 mg/kg)
reached a maximum mean reduction of swelling of 15% after
1 h. After 2 h of treatment, 30 mg/kg dose of Aframomum
meleguta (seeds) extract suppressed carragenan-induced
inlammation by 5%. The inhibitory effects of this lowest
dose (30 mg/kg) of Aframomum meleguta (seeds) extracts
peaked after 3 h but was the lowest recorded of the series of
maximal inhibitions (5%) and it further declined in intensity
to 1% after 5 h.
Time course of anti-inlammatory response evoked by
the Strophanthus hispidus (roots)-Aframomum meleguta
(seeds) co-extract showed brief trends of increasing anti-
inlammatory effects within the 5 h timeline (Figure 2(iii)).
Chicken treated with the lower dose of co-extract (3 mg/kg)
experienced reduced swelling of the foot to below 10% after
4 h p.t. and to less than 5% at the completion of experiment
5 h p.t. Maximum inhibitory effects triggered by this 3 mg/
kg dose therefore occurred 4 h after co-extract treatment.
Inlammation inhibition intensiies at the higher dose (10
mg/kg) of co-extract showing a co-extract time-course that
has a highest rate of inlammation suppression of 10% (2 h
p.t.), 7% (3 h p.t.) and 2% (4 h p.t.). Peak inhibition induced
by the 10 mg/kg dose of the co-extract mixture occurred at
a considerably shorter time (2 h) and was fairly sustained
for a longer duration (approximately 2 h) than for individual
extract.
Inlammation suppressive effects for control drugs across
the different dose ranges (1-10 mg/kg for Dexamethasone;
10-100 mg/kg for Diclofenac) within the 0-5 h time course
range reveals relatively higher anti-inlammatory eficacies
compared to that of test extracts (Figure 3). The lowest
dose (1 mg/kg) of the steroidal anti-inlammatory drug
dexamethasone demonstrated signiicant inhibition of
inlammation compared to vehicle-treated controls as it
triggered a 15% maximal reduction in oedema volumes after
2 h (Figure 3). A 3 mg/kg dose of dexamethasone lowered the
inlammatory response by 10% in the foot oedema at 3 h p.t.
A surprisingly weaker anti-oedematous response occurred
at the highest dose of 10 mg/kg where the drug-induced
decrease in inlammation was a marginal 1% after 4 h.
After 3 h p.t. the 10 mg/kg dose of diclofenac - the
structurally unrelated nonsteroidal anti-inlammatory agent
evoked a maximum anti-inlammatory response of 5%.
Inlammation decreased by approximately 4% in response
to 30 mg/kg dose of diclofenac (Figure 3) at 4 h p. t. and by
about 2% in response to 100 mg/kg dose at 1 h p. t. Maximum
anti-inlammatory response for diclofenac was recorded by
the 10 mg/kg dose as 5% at 3 h p. t.
Dose-response of test samples in anti-infl ammation
activities
Graded anti-inlammatory responses evoked by the 7-day
old chicks following ingestion of graded doses of test samples
in the carrageenan-induced chick feet assay are shown in
(Figure 4). In all test cases, average inlammation inhibitory
responses correlated quantitatively with graded doses of
administered test samples including those of the individual
extracts, co-extract and control drugs (p < 0.05).
A 300 mg of Strophanthus hispidus (roots) extract
yielded an approximate 80% inhibition of inlammation
while a lower dose of 100 mg yielded 75% anti-oedematous
effect. Chicken treated with a lowest dose of Strophanthus
hispidus (roots) extracts (30 mg/kg) had mean reduction of
swelling of 30% (Figure 4(i)). A quantitative and qualitative
pattern of dose–response relationship comparable to that
of Strophanthus hispidus (roots) was observed with that of
Aframomum meleguta (seeds) where the 300 mg/kg of its
extract gave 70% anti-inlammatory response (Figure 4(ii)).
A 62% suppressive effect was obtained after 100 mg/kg dose
of Aframomum meleguta (seeds) extract treatment. Feeding
the chicks with 30 mg/kg of Aframomum meleguta (seeds)
extract evoked up to 60% inhibition of inlammation.
Similar to the anti-inlammation triggered by the
individual extracts, a display of a clear correlation between
the concentration of the Strophanthus hispidus (roots)-
Aframomum meleguta (seeds) co-extract mixture and the
suppressive volume of oedema levels was noted (Figure
4(iii)). At 10 mg/kg, co-extract reduced the swelling of feet
by 80% (Figure 4(iii)). A lower dose of co-extract (3 mg/
kg) proportionally reduced swelling by 75% (Figure 4(iii)).
Co-extract suppressive eficacies of the two tested lower
doses (3, 10 mg/kg i.p.) were quantitatively comparable to
the oedema suppression yielded by the highest doses (300
mg/kg) of individual Strophanthus hispidus (roots) and
Aframomum meleguta (seeds) extracts producing at least 10-
fold dose difference. In fact co-extract treatment of 3 mg/kg
was a more effective anti-inlammatory agent than the higher
dose (100 mg/kg) of Strophanthus hispidus (roots) extract
alone or of Aframomum meleguta (seeds) extract alone.
Comparatively lower doses of diclofenac (10, 30, and
100 mg/kg i.p) were far more effective anti-inlammatory
agents than the higher doses of the individual extracts (30,
100 and 300 mg/kg i.p) yielding, respectively 30%, 33%
and 45% reduction in the swelling of feet (Figure 5). Anti-

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
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inlammatory eficacies higher than that of diclofenac were
observed in response to graded quantitatively lower doses
of dexamethasone (1, 3, and 10 mg/kg i.p). Dexamethasone
treatment (1.0, 3.0, 10.0 mg/kg, i.p) was similarly more
effective than the higher doses (30, 100 and 300 mg/kg i.p)
of both individual Strophanthus hispidus (roots) extract and
separate Aframomum meleguta (seeds) extracts yielding
respectively 30%, 45% and 55% suppressive effects.
Synergy in anti-infl ammation activities
The data shows that co-extract mixture evoked anti-
inlammatory potency on a quantitative scale comparable
to that shown by the two control drug. Co-extract at 3 mg/
kg signiicantly reduced the mean feet oedema of the chicks
to levels comparable to that of the steroidal positive control
drug dexamethasone at 1 mg/kg and to the nonsteroidal
anti-inlammatory drug Diclofenac at 30 mg/kg (Figures
4,5). Also, the anti-inlammatory effect of the co-extract at
10 mg/kg represents at least a 3-fold greater suppressive
effect relative to 100 mg/kg of Strophanthus hispidus (roots)
extract and a 2-fold higher inhibitory effect relative to 100
mg/kg of Aframomum meleguta (seeds) extract (Figure 4).
Co-extracts was similarly robust at lower concentrations
as its co-administration at 3 mg/kg yielded at least a 3-fold
higher anti-inlammation in the chick foot oedema relative to
either Strophanthus hispidus (roots) or Aframomum meleguta
(seeds) extracts alone at 10 mg/kg (Figure 4). In fact, the
combined effects of Strophanthus hispidus (roots) extract
and Aframomum meleguta (seeds) extract were synergistic
(an overall 4–7-fold greater anti-inlammatory effect).
Comparative EC50 values of test extracts in anti-
infl ammation activities
Relative EC50 values of test samples were a consistent
match with observed dose-responses of anti-inlammatory
effects. The Strophanthus hispidus (roots)-Aframomum
meleguta (seeds) co-extract exhibited a highest potency of
the three test extracts with an EC50 va lue c ompar able to t hat
of the standard control drugs dexamethasone and diclofenac
(Table 7). With an EC50 of 117 (4-fold less potent than that
of the co-extract), Strophanthus hispidus (roots) extract was
a fourth as potent as the co-extract mixture. Aframomum
meleguta (seeds) extract showed the lowest potency in the
series of tested extracts with an EC50 that is 7-fold higher
than that of the co-extract mixture. Estimated EC50 values
of test extracts followed the order: Strophanthus hispidus
(ro ots)- Aframomum meleguta (seeds) co-extract mixture
< Strophanthus hispidus (roots) extract < Aframomum
meleguta (seed s) extract.
Discussion
Key observations derived from this study were that crude
co-extract phytochemical pool originated from the mixture
of Strophanthus hispidus (roots) and Aframomum meleguta
(seeds) extracts synergistically inhibits inlammation in vivo
and nominally suppresses microbial growth and scavenges
free radicals in vitro. Collective bioactivities were triggered by
multi-constituent and phytochemically-diverse extracts. And
their evocation is unsurprising because such multifunctional
phytochemical groups including saponins, lavonoids,
alkaloids, glycosides, carotenoids and anthraquinones
are broadly known to provide protective effects against
inlammation, to offer effective microbiocidal activities and
to enhance the ability of cells to scavenge ROS and to resist
oxidative stress [7-13].
The diversity of phytochemical compositions afirms,
in mechanistic terms, the execution of multi-mechanisms
at multi-target sites by bioactive constituents [17]. The
variety of chemotypes of phytochemicals, the miscellany of
phytochemical targets, the multiplicity of phytochemical-
dependent mechanistic action and the assortment of
mechanistic inter-relationships evoked by different extract
phytochemicals within the pool of bioactive constituents
likely account for the varied scope of observed bioactivities.
Differences in phytochemical chemotypes as well as
variability in their relative quantitative amounts account
for differences in the relative extract potencies exhibited by
extracts and co-extracts for the three examined bioactivities.
Within this context, the observed synergy in the co-
extract anti-inlammation is likely attributable to its
wider chemodiversity pool that enables multiple and
complementary phytochemicals access to new target
sites inaccessible or unavailable to the limited pool of
phytochemicals in the individual extracts [18]. Possibly,
pooled phytochemicals from both extracts within the co-
extract mixture might functionally cooperate as their
collective activities overlap and reinforce each other into
a net more potent complementary whole [4,5]. Literature
reports attribute the swelling of chick foot in the carrageenan-
induced inlammations to dysregulated NF-kB pathway
genetic activities [19]. The data suggests that phytochemical
combinations from the co-extract complementarily induce
and/or inactivate NF-kB pathway genes to potentiate a
more effective anti-inlammatory response. Dependence
of anti-inlammation effect on extract concentration shows
that functional mechanistic engagement of phytochemicals
on the NF-κB pathway gene is calibrated physiologically to
correspond with graded doses of extracts.
Functional linkage between the key molecular participants
involved with the co-extract phytochemical responses to the
anti-inlammation, anti-microbial and anti-oxidant activities
was not established. Extract phytochemicals act as anti-
Table 7: ED50 of individual extracts, co-extract mixture and standard drugs.
Sample ED50 (mg/kg)
Strophanthus hispidus extract 117.4
Aframomum melegueta extract
Co-extract mixture
203.3
30.2
Dexamethasone 20.43
Diclofenac 37.51

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
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oxidants presumably through the induction of genes that are
involved in the maintenance of cellular redox balance with
activities that include de-activation of pathways that generate
reactive oxygen species (ROS) or triggering pathways that
increases cellular resistance to oxidative stress in vivo [20].
Although the co-extract emerges as moderately inhibitory
to ROS generation, it nevertheless falls short of the scavenging
activity evoked by Aframomum meleguta extract. The lack
of increase in DPPH scavenging eficacy of the co-extract
over that of the Aframomum meleguta extracts implies that
the customary increases in the diversity of phytochemical
chemotypes afforded by the co-extracts did not lead to a
more active inhibitory effect on ROS generation or more
broadly, did not offer a more potent anti-oxidant effect.
Co-extract phytochemical constituents triggered either an
up-regulation and/or down-regulation of some network
genes whose gene products allow the cellular machinery to
trigger just a nominal anti-oxidant response. As with anti-
inlammation, extracts and co-extracts dose-dependently
scavenged DPPH radicals indicating the reliance of DPPH
scavenging on the quantitative amount of the co-extract’s
polyphenolic and other anti-oxidant phytochemical content.
The demonstration of a broad spectrum microbiocidal
effect by the co-extract is in line with its observed
phytochemical diversity. Despite the lack of consistency in
maintaining the lowest MIC with some microbes, the weight
of the overall experimental evidence points to the co-extract
as the modestly potent microbicide. However the underlying
reason for the failure of the co-extract to evoke synergy in its
microbiocidal effect can only be speculated. Mechanistically,
extract phytochemicals likely target multiple anti-microbial
molecular events such as eflux pump inhibitory signaling and
quorum quenching signaling pathways leading to the eventual
exhibition of bactericidal and/or bacteriostatic action of the
extracts and of the co-extracts [21]. The lack of any synergistic
microbiocidal effect on pathogenic microorganisms suggests
that none of the operative mechanism of inhibition utilized by
individual phytochemicals in distinct extracts complements
or reinforces the other when combined in the co-extract. The
possibility also exist that there might be mutually antagonistic
activities of individual phytochemicals in the pool as their
activities at speciic sites might oppose activities at other
sites. Similar anti-oxidant and anti-microbial patterns of
eficacy of individual plant extracts have been conirmed [7-
13].
Co-extract phytochemicals likely target multiple genetic
molecular events such as impairment of redox balance,
anti-microbial and anti-inlammatory signaling involved in
sinusitis. These bioactive effects of the extracts are possibly
inter-related and they afford as biochemical consequence
prevention, growth control and therapy of sinusitis. Thus,
the observed synergy in anti-inlammatory action of the co-
extracts probably relects not just activation/deactivation
of NF-kB genes but also effects on many other important
mediators of inlammation that are at the intersection of
anti-oxidant and anti-microbial activities. Past reports on
phytochemical synergy are instructive for its use of at least
one pure compounds as one of the synergists [22-29]. And
scientiically supported examples of phytochemical synergy
in the ethnomedicinal remedy terrain are not rare [4,5,30].
Deep historical knowledge about its lack of toxicity and
enduring experiential knowledge about its good eficacy
against chronic sinusitis continue to support the clinical
utility of the co-extract in ethnomedicine. Despite the
wealth of scientiic information on individual uses, there is
surprisingly no literature report that has deined the acute
and chronic toxicity proiles of both plants. Such toxicity
concerns will ultimately have to be addressed scientiically
if widespread clinical utility across both ethnomedicinal
and allopathic medicine is desired. The identiication of
phytochemical synergy in its anti-inlammatory action is of
high clinical signiicance and its importance goes beyond the
obvious offer of therapeutic advantage over use of individual
plants. Potential structurally and mechanistically diverse
phytochemical set from the co-extract mixture may enhance
chronic sinusitis management outcomes or may even help to
achieve durable clinical control of the disease. Altogether, the
clinical signiicance of the study is that Strophanthus hispidus
(roots) extract in combination with Aframomum meleguta
(seeds) extract provides a superior therapeutic index through
mechanistic synergy that offers health beneicial advantage
in the ethnomedicinal management of chronic sinusitis.
Between the phytochemical synergism in anti-
inlammation effects on one hand and non-synergistic, non-
additive anti-oxidant and anti-microbial effects on the other,
the mechanistic interpretation of the bioactivities of the co-
extract is currently mired in speculation. But how the co-
extract phytochemicals trigger these divergent biochemical
effects are issues of current interest. The discovery of the
identity of the phytochemical synergistic, the detection of
the putative molecular targets and the assessment of the
mechanistic inter-relationship between the phytochemical
synergists for its potent anti-inlammatory response will
move this study towards the much needed phytochemical
mechanistic speciicity.
Summary/Conclusion
In Ghanaian ethnomedicine where the mixture of
aqueous extracts of Strophanthus hispidus (roots) and
Aframomum meleguta (seeds) is known to possess signiicant
chemotherapeutic effects against chronic sinusitis, no
evidentiary scientiic support base for this enduring expertise
exist. This study shows that potential phytochemical
synergy between extracts of Strophanthus hispidus (roots)
and Aframomum meleguta (seeds) evokes a robust anti-
inlammatory activity in vivo. Methanol extract of each plant

Co-extract mixture from Strophanthus hispidus (roots) and Aframomum meleguta (seeds) show phytochemical synergy in its anti-infl ammatory
activity
https://www.heighpubs.org/hps 099
https://doi.org/10.29328/journal.apps.1001019
shows high phytochemical diversity with functionalities
including lavonoids, alkaloids and anthraquinones that have
frequently been implicated in multiple bioactivities such as
those of anti-microbial, anti-oxidant and anti-inlammation.
Overall, individual extracts and co-extracts showed a broad
range of microbicide eficacies across a panel of 5 pathogenic
microbes. Individual extracts demonstrated stronger anti-
microbial eficacies against the microbial test panel than did
the co-extracts mixture. Co-extract mixtures and individual
extracts showed comparable potencies in in vitro anti-
oxidant DPPH radical scavenging assays.
Co-extract-mediated suppression of carrageenan-
induced swelling of chick foot exceeded the quantitative sum
of that of the individual-extract-mediated anti-inlammatory
responses. Taken together, these observations are strongly
suggestive of a lack of phytochemical synergies or even of
the absence of functional mechanistic additiveness for anti-
microbial and anti-oxidant properties but are indicative of
a synergistic mode of functionality of phytochemicals in the
co-extract for anti-inlammation. This study concludes that
the use of the co-extracts of Strophanthus hispidus (roots)
and Aframomum meleguta (seeds) will signiicantly inhibit
microbial activities, will provide substantial antioxidant
effects and will exert potent synergistic anti- inlammatory
eficacy. Optimal chemopreventive and chemotherapeutic
potential of both plants as anti-inlammatory agent
therefore resides in the co-extract where its pool of bioactive
phytochemicals functionally interact to generate synergy.
The study therefore lays the groundwork for a larger
future study whose focus will be on the identiication of
the speciic phytochemicals responsible for the synergy in
the anti-inlammatory response. Isolation of the synergistic
anti-inlammatory phytoconstituent(s) could propel
Strophanthus hispidus (roots) and Aframomum meleguta
(seeds) ethnomedicinal recipe in a new direction towards
drug discovery.
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https://www.heighpubs.org/hps 0100
https://doi.org/10.29328/journal.apps.1001019
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