Phytochemistry and Pharmacology of Bombax and Pseudobombax: Evidence-Based Insights and Current Limitations

Abstract

The genera Bombax and Pseudobombax (Malvaceae) are widely used in traditional medicine. This narrative review provides a hierarchical appraisal of their phytochemical and pharmacological profiles based on 35 studies, identifying 22 biological activities. A pronounced taxonomic bias was observed, with research heavily concentrated on Bombax ceiba, while other species, particularly within Pseudobombax, remain poorly explored. Hierarchical analysis indicates that Bombax reaches Level I evidence in metabolic and organ-protective activities, whereas Pseudobombax is largely limited to preliminary Levels II–III. Although antioxidant activity is the most frequently reported effect, it is predominantly supported by in vitro assays with limited physiological relevance. A morphological bias was also evident, with studies prioritizing stem bark and leaves over seeds and roots. Overall, the evidence reveals a significant translational gap, marked by the scarcity of pharmacokinetic data and mechanistic studies. Future research should prioritize standardized, mechanism-driven approaches and expand taxonomic coverage to advance the therapeutic potential of these genera.

1. Introduction

The use of medicinal plants continues to be a pivotal strategy for the discovery of bioactive compounds and the development of new therapeutic agents. Plant-derived metabolites have demonstrated significant pharmacological relevance, reinforcing the necessity of scientific validation for traditionally used species. Among plant families with recognized medicinal potential, Malvaceae stands out due to its wide distribution in tropical and subtropical regions and its richness in species capable of producing structurally diverse secondary metabolites [1].

Within this family, the genera Bombax and Pseudobombax (subfamily Bombacoideae) comprise large tropical tree species distributed mainly across Central and South America [2]. Species from these genera have been traditionally employed to treat inflammatory disorders, infections, metabolic diseases, and skin-related conditions. In recent years, experimental studies have reported several biological activities associated with extracts and isolated compounds, including antioxidant, anti-inflammatory, antimicrobial, cytoprotective, and metabolic regulatory effects [3,4,5]. These properties are frequently attributed to phenolic compounds, flavonoids, and terpenoids.

Despite the growing number of studies, scientific evidence regarding the phytochemical composition and pharmacological activities of Bombax and Pseudobombax remains fragmented. Most investigations focus on a limited number of species, particularly Bombax ceiba, while most of the genera remain poorly explored. Additionally, existing studies often evaluate different plant parts and employ heterogeneous experimental approaches, hindering direct comparisons and limiting broader conclusions regarding their pharmacological relevance [6]. This gap is particularly evident in high-biodiversity regions, such as Brazil, where native species represent a vast, yet underexplored, reservoir of bioactive molecules [7,8].

Previous review studies have addressed specific aspects of Bombax species. For example, Kumari et al. [9] summarized the phytochemical composition, biological activities, and nutraceutical potential of Bombax ceiba flowers, highlighting their relevance as functional food ingredients. Earlier reviews have also discussed the traditional uses and medicinal properties of Bombax species. However, these studies generally focused on specific species, plant organs, or thematic aspects. To our knowledge, no previous review has comprehensively integrated the phytochemical and pharmacological evidence available for both Bombax and Pseudobombax species. This gap underscores the need for a broader and updated synthesis of the current knowledge regarding these genera.

Considering these limitations, the present study aims to compile and critically analyze the available literature on the phytochemical constituents and pharmacological activities described in the literature of Bombax and Pseudobombax. This narrative review seeks to address the following questions: (i) which pharmacological activities present the strongest experimental evidence; (ii) which species and plant parts remain underexplored; and (iii) what are the main gaps that should guide future phytochemical and pharmacological investigations. Ultimately, this work intends to contribute to a better understanding of the therapeutic potential of these genera and support future efforts in natural product discovery.

2. Materials and Methods

2.1. Study Design

This study was conducted as a narrative literature review aiming to compile and critically analyze available scientific evidence regarding the phytochemical constituents and pharmacological activities of species belonging to the genera Bombax and Pseudobombax. The narrative review approach was selected due to the heterogeneity of experimental designs, plant parts evaluated, extraction methods, and biological models reported in the literature, which limits the applicability of systematic review methodologies and meta-analysis. Although this approach allows broader conceptual interpretation, it may present limitations related to study selection bias and variability in methodological quality.

2.2. Literature Search Strategy

The literature search was conducted between March and December 2025 using the PubMed and ScienceDirect databases, considering their relevance in pharmacology, phytochemistry, ethnopharmacology, and natural product research.

The following descriptors were used:

• “Bombax”;
• “Bombax AND pharmacological activity”;
• “Pseudobombax”;
• “Pseudobombax AND pharmacological activity”.

Search terms were combined using Boolean operators (“AND” and “OR”) to expand the retrieval of relevant publications. Only studies published between 2013 and 2025 and written in English were considered.

2.3. Eligibility Criteria

Studies were selected based on the following criteria: (i) presentation of experimental evaluation of biological or pharmacological activities; (ii) investigation of extracts, fractions, or isolated compounds from Bombax or Pseudobombax species; (iii) availability of full-text access; and (iv) publication as peer-reviewed original research articles.

Studies were excluded if they: (i) mentioned the target genera only superficially; (ii) lacked experimental biological or pharmacological data; or (iii) were conference abstracts, editorials, or duplicated publications. Review articles were excluded to prioritize primary experimental data; however, relevant reviews were consulted to support the contextual interpretation and discussion of findings.

Despite our efforts to conduct a comprehensive literature survey, some potentially relevant publications may not have been included. The selection of studies was guided by predefined eligibility criteria and methodological considerations established for this review. Consequently, the absence of a particular study should not be interpreted as a judgment regarding its scientific merit or importance. We apologize for any inadvertent omissions and recognize that additional publications may offer meaningful insights into the topic discussed herein.

2.4. Study Selection Process

The initial search identified 1702 publications related to Bombax and 270 publications related to Pseudobombax. After applying the defined temporal filter (2013–2025), 1173 studies related to Bombax and 168 related to Pseudobombax remained.

Titles and abstracts were screened to evaluate relevance according to the eligibility criteria. Following this step, 31 articles involving Bombax species and 6 articles involving Pseudobombax species were selected for full-text analysis and data extraction.

A flow chart summarizing the study selection process is presented in Figure 1.

2.5. Data Extraction and Synthesis

All selected studies underwent full-text analysis. Data were extracted and organized into a descriptive matrix comprising the following variables:

• Botanical species investigated;
• Plant part(s) utilized;
• Type of extract, fraction, or isolated compound;
• Biological or pharmacological activity evaluated;
• Experimental model employed (in vitro, in vivo, or in silico);
• Identified bioactive compounds (when applicable).

Subsequently, the gathered information was qualitatively categorized and synthesized to identify patterns of pharmacological activity, phytochemical diversity, and potential research gaps within the field.

2.6. Assessment of Evidence Quality

Due to the diversity of experimental approaches, a formal risk-of-bias tool was not applied. Instead, the overall quality of evidence was assessed qualitatively by considering the experimental models used, reproducibility of findings, and level of biological validation.

Most studies involved in vitro assays or animal experimental models, with limited clinical validation. Additionally, considerable variability was observed regarding extraction methods, phytochemical characterization, and pharmacological protocols, which restricts direct comparison between studies and highlights the need for standardized experimental designs in future investigations.

2.7. Hierarchical Classification of Evidence Strength

To contextualize the robustness of the available data and to avoid overstatement of therapeutic potential, the reported biological activities were classified according to experimental depth and translational relevance (

Table 1. Hierarchical classification of evidence strength for reported biological activities in Bombax and Pseudobombax species.

Evidence Level	Definition	Minimum Experimental Criteria	Typical Study Design Observed	Main Limitations Identified
Level I	In vivo validation with biochemical and/or molecular mechanistic markers	Established disease model + biomarker quantification + dose–response analysis	Rodent disease models with biochemical endpoints	Limited molecular pathway validation; absence of clinical follow-up
Level II	Functional in vivo evidence without detailed mechanistic elucidation	Disease model + functional outcome measurement	Animal models without molecular confirmation	Lack of target-specific validation
Level III	In vitro cellular or biochemical assays	Cell viability, enzyme inhibition, or radical-scavenging assays	Cell culture models, DPPH/ABTS assays	No in vivo confirmation; limited physiological relevance
Level IV	Exploratory or limited evidence	Qualitative or preliminary assays	Screening assays without replication or controls	Insufficient experimental rigor

).

To the best of our knowledge, no standardized framework currently exists for hierarchically classifying heterogeneous pharmacological evidence in Bombax and Pseudobombax studies. Therefore, this hierarchical framework was developed by the authors specifically for the present review, aiming to provide a standardized and transparent approach to compare heterogeneous pharmacological evidence across studies involving Bombax and Pseudobombax species.

The classification criteria were defined based on three main parameters:

(i)

The level of biological complexity (in vitro vs. in vivo);

(ii)

The presence of functional versus mechanistic outcomes;

(iii)

The degree of experimental validation, including dose–response relationships and biomarker assessment.

Thus, four levels of evidence were established:

• Level I: Studies with in vivo validation supported by biochemical and/or molecular mechanistic markers, including dose–response relationships.
• Level II: In vivo studies demonstrating functional outcomes without detailed mechanistic elucidation.
• Level III: In vitro studies assessing cellular or biochemical activities.
• Level IV: Exploratory or preliminary studies with limited experimental rigor.

This approach allows for a more critical interpretation of the literature, emphasizing not only the presence of biological activity but also the strength and translational relevance of the supporting evidence.

3. Results

3.1. Study Identification and Selection

By December 2025, the initial database search identified 1702 publications related to the genus Bombax and 270 related to Pseudobombax (Figure 1). Following the application of temporal and eligibility criteria, 1173 and 168 articles remained, respectively. Subsequent screening of titles and abstracts led to the selection of 31 Bombax species articles and six Pseudobombax species articles for full-text analysis. Ultimately, only 37 studies met the inclusion criteria for qualitative synthesis, representing approximately 2.6% of the initially screened Bombax records and approximately 3.5% of the Pseudobombax records. This significant reduction (Figure 1) underscores the paucity of studies specifically addressing phytochemical characterization coupled with experimentally validated pharmacological activity within the established scope.

3.2. General Characteristics of the Evidence Base

A structured synthesis of the included studies (encompassing investigated species, plant organs, extraction strategies, phytochemical profiling, and reported biological activities) is detailed in

Table 2. Reported biological activities of Bombax species, including experimental models, plant parts, and associated metabolites.

Species	Chemical Class	Major Compounds	Plant Part/Extract	Reported Biological Activities	References
Bombax ceiba L.	Phenolic acids	Gallic acid, protocatechuic acid, chlorogenic acid	Leaves, flowers, calyces	Antioxidant, hypoglycemic, cytotoxic, gastroprotective	[4,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30]
Bombax ceiba L.	Flavonoids	Rutin, quercetin, isovitexin, vitexin, isoorientin	Leaves, flowers, calyces	Antioxidant, antihyperglycemic, antihyperlipidemic, hepatoprotective	[11,14,16,21,27]
Bombax ceiba L.	Xanthones	Mangiferin, isomangiferin	Leaves, flowers, roots	Antiviral, antidiabetic, nephroprotective, antihyperglycemic	[14,19,20,31]
Bombax ceiba L.	Coumarins	Scopoletin	Flowers, calyces	Antioxidant, antiglycation	[16,26]
Bombax ceiba L.	Phytosterols/Triterpenoids	β-Sitosterol, lupeol	Bark, stem bark, flowers	Antiobesity, antiosteoporotic, cytotoxic	[4,22,29,32]
Bombax ceiba L.	Polyphenols/tannins	Polyphenols, tannins	Leaves, bark, Flowers	Antioxidant, hepatoprotective	[10,11,12,13,14,15,16,17,18,19,21]
Bombax ceiba L.	Sugars and polyols	Myo-inositol, xylitol, D-sedoheptulose	Flower calyx	Antiglycation	[26]
Bombax ceiba L.	Miscellaneous metabolites	Nigricanoside	Leaves	Antihyperglycemic, antihyperlipidemic	[14]
Bombax costatum Pellegr. & Vuillet	Not chemically characterized		Stem bark	Anti-inflammatory, anti-arthritic, antihistaminic, antidepressant, antiamnesic	[33,34]
Bombax buonopozense P. Beauv.	Not chemically characterized		Root bark	Antiplasmodial	[35]

Only experimentally validated studies meeting the inclusion criteria were considered. When available, structurally characterized metabolites are listed.

and

Table 3. Reported biological activities of Pseudobombax species, including experimental models, plant parts, and associated metabolites.

Species	Chemical Class	Major Compounds	Plant Part/Extract	Reported Biological Activities	References
Pseudobombax parvifolium A.DC.	Norisoprenoids	Loliolide	Stem bark	Antioxidant	[5]
Pseudobombax ellipticum (Kunth) Dugand	Phenolic acids	Phenolic acids	Stem bark	Antioxidant, antibacterial	[36]
Pseudobombax ellipticum (Kunth) Dugand	Flavonoids	Flavonoids, rutin, kaempferol-3-O-glucoside	Stem bark; fresh Flowers	Antioxidant, antibacterial, antisickling	[36,37]
Pseudobombax ellipticum (Kunth) Dugand	Anthocyanins	Pelargonidin-3-O-glucoside, cyanidin-3-O-rutinoside	Fresh flowers	Antioxidant, antisickling	[37]
Pseudobombax simplicifolium A. Robyns	Phenolic compounds	Phenolic compounds	Stem bark	Antioxidant	[38]
Pseudobombax simplicifolium A. Robyns	Flavonoids and tannins	Flavonoids, tannins	Stem bark	Antioxidant	[38]
Pseudobombax ellipticum cultivar alba Hort.	Anthocyanins	Pelargonidin-3-O-glucoside, cyanidin-3-O-rutinoside	Fresh flowers	Antisickling, antioxidant	[37]
Pseudobombax ellipticum cultivar alba Hort.	Flavonoids	Rutin, kaempferol-3-O-glucoside	Fresh flowers; stem bark	Antioxidant, antisickling	[37]
Pseudobombax marginatum (A. St.-Hil.) A. Robyns	Flavonoids, tannins, and coumarins	Flavonoids, tannins, coumarins	Stem bark	Cytoprotective, genoprotective	[39]
Pseudobombax marginatum (A. St.-Hil.) A. Robyns	Not chemically characterized		Stem bark	Anti-inflammatory, antinociceptive	[40]

Only experimentally validated studies meeting the inclusion criteria were considered. When available, structurally characterized metabolites are listed.

and visually summarized in Figure 2 and Figure 3. The overall evidence landscape reveals a marked asymmetry between the two analyzed genera.

Of the 37 included studies, 83.7% focused on Bombax, while only 16.2% investigated Pseudobombax, demonstrating a pronounced taxonomic imbalance. Within Bombax, B. ceiba predominated with 28 publications, representing 90.3% of the genus-specific research and 75.7% of the total selected articles. Conversely, other species such as B. costatum and B. buonopozense were minimally represented. In the six studies involving Pseudobombax, the distribution was more equitable among P. ellipticum (33.3%), P. marginatum (33.3%), P. simplicifolium (16.7%) and P. parvifolium (16.7%), with no single species showing research dominance comparable to B. ceiba.

This concentration pattern suggests that research efforts have been driven primarily by historical usage, geographic accessibility, and legacy phytochemical data rather than by systematic taxonomic or comparative strategies. Consequently, pharmacological generalizations at the genus level remain constrained, particularly for Pseudobombax, where the evidence base is sparse.

The organ-specific distribution of biological activities for the genera Bombax and Pseudobombax is visually synthesized in Figure 2 and Figure 3, respectively. While these mappings underscore a multifaceted pharmacological profile, the broader evidence landscape reveals a significant taxonomic disparity. Regarding plant morphology, leaves, flowers, and stem bark were the most frequently investigated organs overall. However, this distribution varies strictly by taxa: Bombax species were evaluated across a wide range of plant parts (Figure 2), whereas Pseudobombax investigations remain largely restricted to stem bark and flowers (Figure 3). Such preference appears to reflect research convenience and geographic accessibility rather than demonstrated phytochemical superiority. Consequently, the scarcity of systematic organ-to-organ comparisons limits robust conclusions regarding tissue-specific bioactive potential, particularly for the less-studied Pseudobombax.

Methodological heterogeneity was also pervasive across the literature. Experimental designs varied significantly in extraction procedures, the depth of chemical characterization, and the selection of biological validation models. Several studies relied on crude extracts lacking standardized profiling, and inter-study comparability was often hindered by inconsistent reporting of experimental parameters. Such variability constrains reproducibility and complicates the integrative interpretation of pharmacological evidence.

Collectively, the current body of literature reveals a research landscape characterized by taxonomic concentration, organ-level selectivity, and methodological disparity. While both genera exhibit significant biological activity and phytochemical richness, the uneven distribution of investigative efforts highlights the urgent need for broader species coverage, standardized analytical profiling, and systematic comparative approaches.

3.3. Phytochemical Characterization: Analytical Scope and Depth

As summarized in Table 2 and Table 3, phytochemical investigations of Bombax and Pseudobombax species predominantly reported phenolic compounds, flavonoids, tannins, alkaloids, terpenoids, and polysaccharides. Analytical characterization was mainly conducted using chromatographic and spectrometric techniques, including high-performance liquid chromatography (HPLC) coupled with diode-array detection (DAD), liquid chromatography–mass spectrometry (LC–MS/MS), and gas chromatography–mass spectrometry (GC–MS).

In most studies, compound identification was based on retention times, UV absorption spectra, and mass fragmentation patterns, often compared with reference standards or spectral libraries. However, detailed analytical parameters, such as column type, mobile phase composition, gradient elution profiles, ionization modes, and mass analyzer settings, were inconsistently reported, limiting reproducibility and cross-study comparisons.

Bombax ceiba exhibited the most chemically characterized profile, with recurrent detection of compounds such as mangiferin, β-sitosterol, gallic acid, and lupeol. These identifications were frequently supported by LC–MS fragmentation data or co-elution with authentic standards. In contrast, phytochemical data for other species were sparse and often restricted to preliminary screening assays or non-targeted analyses without compound confirmation.

Notably, the analytical scope remained largely qualitative. Only a minority of studies employed quantitative approaches, such as calibration curves with external standards or internal normalization methods, to determine the concentration of individual metabolites. Additionally, validation parameters, including limits of detection (LOD), limits of quantification (LOQ), precision, and accuracy, were rarely addressed.

Despite the use of advanced analytical platforms, several methodological limitations were consistently observed:

• Limited quantitative rigor: Few studies provided absolute or relative quantification of bioactive compounds using validated analytical methods.
• Heterogeneity in extraction procedures: Variability in solvent polarity (e.g., methanol, ethanol, aqueous systems), extraction techniques (maceration, Soxhlet, ultrasonic-assisted extraction), and plant part selection hindered data comparability.
• Lack of reproducibility assessment: Most studies did not evaluate intra- or inter-batch variability, nor did they consider environmental or seasonal influences on metabolite composition.
• Insufficient use of bioassay-guided fractionation: Isolation and structural elucidation of active compounds using integrated phytochemical–pharmacological approaches remain limited.

Consequently, biological activities were frequently attributed to broad classes of compounds rather than to structurally characterized molecules. Although metabolites such as mangiferin, β-sitosterol, gallic acid, lupeol, and flavonoid derivatives have been repeatedly reported in B. ceiba, direct mechanistic correlations between these compounds and specific pharmacological effects remain inadequately established.

Major Phytochemical Classes and Bioactive Compounds

In addition to general phytochemical screening, several structurally characterized bioactive compounds have been identified across Bombax and Pseudobombax species, predominantly belonging to phenolic derivatives, flavonoids, and triterpenoids. These classes are consistently associated with the pharmacological activities reported in the literature and represent key contributors to the biological potential of these genera.

Among the most frequently reported metabolites, mangiferin stands out as a major bioactive constituent of Bombax ceiba. This compound has garnered significant attention due to its multifaceted antioxidant, anti-inflammatory, and antihyperglycemic properties. Mechanistically, mangiferin mitigates oxidative stress not only through direct radical scavenging but primarily by activating endogenous defense pathways, such as the Nrf2 signaling cascade. Furthermore, its anti-inflammatory and cytoprotective effects are largely mediated via the inhibition of pro-inflammatory mediators (including TNF-alpha and IL-6) and the modulation of the NF-κB pathway [41]. Regarding glucose homeostasis, mangiferin improves insulin sensitivity and regulates carbohydrate metabolism through AMPK-related mechanisms and the inhibition of carbohydrate-hydrolyzing enzymes, highlighting its potential translational relevance in metabolic disorders [42].

Flavonoids represent another major class of secondary metabolites recurrently identified in both genera, with quercetin, rutin, kaempferol derivatives, vitexin, and isovitexin being the most prominent. These compounds exert broad pharmacological effects, ranging from vascular protection to direct free radical scavenging. Among them, quercetin [43] and kaempferol [44] stand out due to their ability to modulate intracellular redox status by targeting ROS-dependent signaling pathways and down-regulating pro-inflammatory cytokine production.

Although the high concentration of these flavonoids is frequently used to explain the potent antioxidant and anti-inflammatory activities observed in Bombax and Pseudobombax extracts, these conclusions remain largely correlative. The limited use of compound-isolation strategies in the current literature prevents the establishment of direct causal relationships, underscoring the need for more rigorous mechanistic validation of these individual constituents.

Triterpenoids and phytosterols represent another chemical and pharmacologically significant group of metabolites identified in Bombax and Pseudobombax species, particularly B. ceiba and P. simplicifolium. Among the triterpenoids, lupeol and taraxerol deserve particular attention due to their reported anti-inflammatory, cytoprotective, and antiproliferative actions. Mechanistically, lupeol has been shown to attenuate oxidative stress and down-regulate NF-κB -mediated inflammatory cascades [45], while taraxerol exhibits complementary anti-inflammatory effects in experimental models [46]. Similarly, the phytosterol beta-sitosterol is widely recognized for its hypolipidemic, immunomodulatory, and hepatoprotective properties, which may underline some of the metabolic regulatory and lipid-lowering effects reported for these plant extracts [47]. Nevertheless, despite the well-documented efficacy of these pure constituents in other botanical systems, their precise contribution to the overall biological activities observed in Bombax and Pseudobombax remains largely unvalidated.

Additionally, simple phenolic compounds such as gallic acid [48] and protocatechuic acid [49] contribute to antioxidant and cytoprotective effects, reinforcing the role of low-molecular-weight phenolics in redox modulation.

Overall, although a diverse range of bioactive compounds has been identified, the current literature is largely based on qualitative detection and class-level attribution. The lack of bioassay-guided fractionation and mechanistic validation limits the establishment of direct relationships between specific compounds and pharmacological effects. This highlights a critical gap and underscores the need for compound-oriented studies integrating phytochemical isolation, structural elucidation, and target-based biological evaluation.

3.4. Genus Bombax

A critical limitation across the evaluated studies is the insufficient integration between phytochemical composition and pharmacological outcomes. While several biological activities are reported, only a limited number of studies establish direct mechanistic links between specific compounds and observed effects. Compounds such as mangiferin, flavonoids, and triterpenoids (e.g., lupeol and β-sitosterol) are frequently cited; however, their individual contributions and molecular targets remain poorly defined.

3.4.1. Biological Activities of Bombax: Critical Appraisal of Experimental Evidence

The spectrum of pharmacological activities reported for Bombax ceiba and related species is broad (Table 2), encompassing antioxidant, anti-inflammatory, metabolic, antimicrobial, and cytotoxic effects. Among these, antioxidant and antidiabetic activities are the most consistently investigated, supported by both in vitro assays (e.g., DPPH, ABTS, enzyme inhibition) and in vivo models, particularly using leaf and flower extracts. These studies frequently associate bioactivity with phenolic compounds such as mangiferin, flavonoids, and phenolic acids.

Metabolically related effects, including antihyperglycemic, antihyperlipidemic, and antiobesity activities, are also relatively well represented, especially in rodent models, suggesting a potential role of B. ceiba in metabolic regulation. Similarly, anti-inflammatory and hepatoprotective effects have been demonstrated in vivo, although often without detailed identification of the active constituents.

In contrast, other reported activities, such as antiviral, antiosteoporotic, anti-arthritic, and neuropharmacological effects, remain limited to a small number of studies, frequently with restricted experimental replication. Antibacterial and cytotoxic activities are commonly reported based on in vitro assays, but their translational relevance remains uncertain due to the lack of complementary in vivo validation.

A recurrent pattern across studies is the association of biological effects with broadly defined chemical classes rather than isolated compounds, which complicates mechanistic interpretation. Additionally, the predominance of single-model studies and the limited integration of pharmacological and phytochemical approaches restrict the robustness of the current evidence base.

Overall, while B. ceiba demonstrates a wide range of promising biological activities, the strength of evidence varies considerably, with the most consistent support observed for antioxidant and metabolic effects and more preliminary evidence for other pharmacological properties.

3.4.2. Antioxidant Activity

Antioxidant capacity represents the most frequently evaluated biological property (Figure 2). Nevertheless, most studies relied on chemical-based assays, such as DPPH, ABTS, and FRAP, which measure radical-scavenging capacity in vitro but do not necessarily translate to physiological redox modulation. Only a limited number of investigations evaluated in vivo oxidative stress biomarkers, and mechanistic insights into endogenous antioxidant signaling pathways (e.g., Nrf2/ARE) were rarely explored. Consequently, while antioxidant activity is consistently reported, its translational relevance remains largely unverified.

3.4.3. Antimicrobial and Antiviral Activities

Antimicrobial activity has been predominantly assessed via in vitro growth inhibition assays (Table 2). While inhibitory effects were observed against multiple pathogenic strains, there is a lack of data regarding pharmacokinetics, systemic toxicity, or efficacy in in vivo infection models. Similarly, antiviral activity (against respiratory syncytial virus—RSV) was demonstrated exclusively in cell-based systems. The absence of mechanistic elucidation and in vivo validation limits the extrapolation of these findings toward therapeutic applications.

3.4.4. Cytotoxic and Anticancer Effects

Cytotoxic activity against various tumor cell lines has been reported (Table 2). However, the evidence is frequently constrained by significant methodological limitations, including:

• Lack of selectivity indices: Failure to evaluate toxicity in non-tumoral (healthy) cell lines.
• Absence of mechanistic confirmation: Lack of data regarding apoptosis induction or cell cycle arrest pathways.
• Inadequate validation: Absence of in vivo tumor xenograft models.
• Pharmacological gaps: No assessment of pharmacodynamic or pharmacokinetic profiles.

As illustrated in Figure 2, cytotoxicity represents a secondary research focus compared to antioxidant screening. Therefore, current findings should be interpreted as preliminary cytotoxic screening rather than substantiated anticancer efficacy.

3.4.5. Metabolic and Organ-Protective Effects

Metabolic and organ-protective activities, including antidiabetic, antihyperlipidemic, nephroprotective, hepatoprotective, and antiosteoporotic effects, were primarily evaluated in rodent models (Table 2). Although improvements in biochemical surrogate markers were commonly observed, molecular pathway validation and target-specific analyses were frequently omitted. While specific secondary metabolites were hypothesized to drive these effects, the definitive molecular mechanisms and their direct targets remain insufficiently established.

3.4.6. Hierarchical Assessment of Evidence Strength

The hierarchical classification framework was applied to all included studies, resulting in the categorization of 23 distinct pharmacological activities (

Table 4. Hierarchical classification and critical appraisal of pharmacological activities reported for Bombax species.

Species	Biological Activity	Evidence Level	Critical Appraisal	Major Methodological Gaps
Bombax ceiba	Antioxidant	III	Activity consistently demonstrated in chemical and cellular assays; physiological relevance remains to be fully established	Limited in vivo confirmation; insufficient redox pathway characterization; extract standardization inconsistently reported
Bombax ceiba	Antiviral	III	Promising in vitro antiviral effect	Absence of in vivo validation; limited host–virus interaction analysis
Bombax ceiba	Hypoglycemic/Antidiabetic	I	Supported by established metabolic models with biochemical endpoints	Molecular target identification and pharmacokinetic profiling remain limited
Bombax ceiba	Antiobesity	II	Functional efficacy demonstrated in diet-induced models	Lack of mechanistic investigation of metabolic signaling pathways
Bombax ceiba	Antibacterial	III	Reproducible in vitro inhibition observed	In vivo infection models and toxicity evaluation not reported
Bombax ceiba	Anti-inflammatory	I	Demonstrated activity in validated inflammatory models	Deeper cytokine profiling and pathway-level analyses are warranted
Bombax ceiba	Anti-arthritic	II	Functional improvement reported in induced arthritis models	Limited molecular mediator assessment
Bombax ceiba	Nephroprotective	I	Biochemical and functional renal protection observed	Mechanistic renal signaling pathways remain underexplored
Bombax ceiba	Hepatoprotective	I	Activity supported by biochemical and histological parameters	Further molecular-level validation desirable
Bombax ceiba	Anticancer/Cytotoxic	III	Cytotoxic activity demonstrated in tumor cell lines	Selectivity in normal cells and in vivo tumor validation lacking
Bombax ceiba	Antihelminthic	IV	Preliminary biological activity observed	Requires in vivo confirmation and pharmacodynamic assessment
Bombax ceiba	Antihyperglycemic	I	Consistent metabolic improvements reported	Direct causative linkage with identified metabolites requires clarification
Bombax ceiba	Antihyperlipidemic	I	Classical lipid biomarkers modulated	Gene-level pathway investigation limited
Bombax ceiba	Antiglycation	III	In vitro AGE inhibition demonstrated	Physiological validation absent
Bombax ceiba	Gastrointestinal	II	Functional improvement observed in vivo	Mechanistic basis remains insufficiently explored
Bombax ceiba	Antihemorrhagic	IV	Activity suggested in cellular systems	Systemic hemostatic validation required
Bombax ceiba	Antiosteoporotic	I	Bone density improvements suggest translational relevance	Molecular osteogenic signaling requires further investigation
Bombax ceiba	Gastroprotective activity	I	Robust dual-model preclinical design; integrated metabolomics + network pharmacology	No clinical data; small sample (n = 6); mechanism not experimentally validated; no PK or biomarker analysis
Bombax costatum	Anti-inflammatory/Anti-arthritic	II	Functional in vivo evidence reported	Mediator-level confirmation limited
Bombax costatum	Antihistaminic	II	Activity supported in pharmacological models	Receptor-level validation not reported
Bombax costatum	Antidepressant	II	Behavioral improvements observed	Neurochemical biomarker evaluation limited
Bombax costatum	Antiamnesic	II	Cognitive benefits demonstrated	Synaptic and neuroplasticity markers not investigated
Bombax buonopozense	Antiplasmodial	II	Activity demonstrated in a relevant infectious model	Expanded replication and molecular target characterization desirable

). Level II evidence predominated (34.8%) with Level I (34.8%), followed by Level III (21.7%) and Level IV (8.7%) (Table 4).

Although 69.6% of the reported activities (Levels I–II) involved in vivo experimental models, only 34.8% fulfilled the criteria for robust validation supported by established disease models and quantifiable biochemical or molecular biomarkers (Level I). In addition, no clinical-level evidence was identified among the included studies.

Activities classified as Level I were primarily associated with metabolic and organ-protective effects, including hypoglycemic, antihyperlipidemic, hepatoprotective, nephroprotective, anti-inflammatory, gastroprotective and osteogenic properties, generally employing validated in vivo models and objective biochemical endpoints. Level II activities comprised functional in vivo evidence lacking detailed mechanistic elucidation (e.g., antiobesity, anti-arthritic, and antidepressant effects). Conversely, Level III evidence was largely restricted to in vitro systems, particularly antioxidant and antibacterial assays, which represent a substantial proportion of the exploratory investigations (Figure 2 and Figure 3). Level IV corresponded to preliminary validation, such as ex vivo or isolated cellular systems without systemic confirmation.

3.5. Genus Pseudobombax

3.5.1. Biological Activities of Pseudobombax: Critical Appraisal of Experimental Evidence

The range of reported pharmacological activities for Pseudobombax is markedly more restricted compared to Bombax (Table 3), with research efforts concentrated on a limited number of species and plant organs.

3.5.2. Antioxidant Activity

As illustrated in Figure 3, antioxidant activity is one of the few properties investigated for this genus. Like the trends observed in Bombax, these evaluations relied almost exclusively on in vitro radical-scavenging assays (e.g., DPPH and ABTS). There is an absence of in vivo redox modulation studies or mechanistic investigations into cellular antioxidant pathways. Consequently, the antioxidant activity of Pseudobombax remains at a preliminary screening stage, lacking physiological validation.

3.5.3. Antimicrobial Activity

Antimicrobial investigations in Pseudobombax are largely confined to in vitro assessments of stem bark extracts (Table 3). Although inhibitory effects against specific bacterial strains have been identified, the evidence base lacks diversity in tested pathogens and is devoid of in vivo efficacy trials, toxicity profiles, or pharmacokinetic data. No antiviral activities were identified for this genus within the evaluated timeframe.

3.5.4. Anti-Inflammatory and Antinociceptive Effects

A significant portion of the research on Pseudobombax (mainly P. marginatum) focuses on anti-inflammatory and antinociceptive properties. While these studies often employ in vivo functional models, such as paw edema or writhing tests, they frequently lack molecular depth. The specific mediators involved and the potential modulation of signaling pathways (e.g., COX-2 or cytokine cascades) remain insufficiently characterized.

3.5.5. Other Biological Properties

Other reported effects, such as antisickling and cytoprotective activities, represent isolated investigative efforts (Figure 3). These findings, while promising, are predominantly based on in vitro or ex vivo models without systemic confirmation. The lack of broader pharmacological screening across different plant parts, such as leaves or roots, limits the understanding of the genus’s full therapeutic potential.

3.5.6. Hierarchical Assessment of Evidence Strength

The hierarchical classification of Pseudobombax research highlights a fragmented evidence landscape. In contrast to Bombax, where Level I evidence is more prevalent, Pseudobombax studies are largely situated at Levels II and III (

Table 5. Critical appraisal of biological activities reported for Pseudobombax species.

Species	Biological Activity	Evidence Level	Critical Appraisal	Major Methodological Gaps
Pseudobombax parvifolium	Antioxidant	I	In vivo antioxidant modulation supported by reduced lipid peroxidation and increased SOD and GPx activity	Absence of pathway-level redox signaling analysis; lack of standardized extract characterization
Pseudobombax ellipticum	Antioxidant	III	Consistent radical scavenging and metal chelation activity in chemical assays	No in vivo confirmation; limited mechanistic elucidation of cellular antioxidant pathways
Pseudobombax ellipticum	Antibacterial	III	Demonstrated inhibition of biofilm formation against Pseudomonas aeruginosa	Lack of in vivo infection models; absence of toxicity and pharmacokinetic evaluation
Pseudobombax ellipticum	Antisickling	III	Reduction in erythrocyte sickling observed in vitro, suggesting hematological relevance	No in vivo validation; mechanism of hemoglobin stabilization not investigated
Pseudobombax ellipticum (cv. alba)	Antioxidant	III	Reproducible antioxidant activity in chemical assays	Limited comparative phytochemical profiling; no biological validation beyond in vitro assays
Pseudobombax ellipticum (cv. alba)	Antisickling	III	In vitro erythrocyte stabilization demonstrated	Translational hematological assessment and systemic validation lacking
Pseudobombax simplicifolium	Antioxidant	IV	Multiple complementary antioxidant assays; phytochemical screening and phenolic/flavonoid quantification; exclusively in vitro	No in vivo/clinical validation; no cytotoxicity or dermatological safety tests; no photostability/formulation studies; no compound isolation or mechanistic assays
Pseudobombax marginatum	Anti-inflammatory	II	Functional reduction in carrageenan-induced edema in vivo	Limited cytokine profiling; absence of molecular inflammatory pathway analysis
Pseudobombax marginatum	Antinociceptive	II	Significant reduction in nociceptive responses in validated rodent models	Mechanistic differentiation between central and peripheral pathways not performed
Pseudobombax marginatum	Cytoprotective/Genoprotective	III	DNA damage reduction demonstrated in comet assay	No systemic confirmation; responsible bioactive compounds not fully isolated

).

Collectively, this distribution (Figure 3) reveals that the evidence base for Pseudobombax is not only smaller in volume but also lower in hierarchical strength. The reliance on a few species and the focus on stem bark research emphasize a significant taxonomic and morphological bias, precluding robust generalizations at the genus level.

4. Discussion

The present narrative review reveals not merely a disparity in research volume between Bombax and Pseudobombax, but a structural imbalance in scientific maturity, mechanistic depth, and translational progression. Although both genera display a wide array of reported biological activities, the evidence landscape is unevenly distributed, with research efforts disproportionately concentrated on a limited number of species and plant organs. This dual taxonomic and morphological bias restricts a comprehensive pharmacological interpretation of these taxa and may obscure chemically distinct and therapeutically relevant species that remain underexplored.

Within Bombax, the overwhelming predominance of B. ceiba likely reflects its broad geographical distribution and long-standing incorporation into traditional Asian medical systems [6]. However, this concentration has shaped the pharmacological identity of the genus in a way that may not accurately represent its internal chemical diversity. While B. ceiba demonstrates relatively advanced experimental validation in metabolic, organ-protective, and osteogenic contexts, other species such as B. costatum and B. buonopozense remain largely confined to functional screening stages. This imbalance narrows phytochemical discovery pipelines and limits opportunities to identify structurally novel metabolites potentially restricted to less-investigated taxa. From a drug discovery perspective, this concentration represents a clear constraint on chemical diversification and translational innovation.

A similar bias is evident at the morphological level. Leaves, flowers, and stem bark dominate the experimental landscape across both genera. Although ethnobotanical guidance partially explains this preference, methodological convenience appears equally influential. As discussed by Penido et al. [50], these organs are readily accessible and, in the case of bark and leaves, often available year-round, facilitating repeated experimental use. Nevertheless, the scarcity of systematic organ-to-organ comparative studies precludes definitive conclusions regarding tissue-specific bioactive superiority. Importantly, flowers are metabolically specialized structures enriched in flavonoids and anthocyanins [51], and the antisickling activity reported in Pseudobombax flowers underscores how underexplored organs may harbor clinically relevant bioactivities. Conversely, the predominant use of stem bark, particularly in Pseudobombax, raises sustainability concerns, as excessive harvesting can compromise plant viability and ecological balance [52]. These findings reinforce the necessity of aligning pharmacological exploration with conservation-aware research strategies.

Perhaps the most consequential finding of this review is the persistence of a pronounced translational gap. Antioxidant activity represents the most frequently reported biological property across both genera; however, its predominance is largely driven by chemical assays such as DPPH and ABTS, which provide limited physiological relevance. The reliance on rapid screening methodologies reflects a broader research paradigm oriented toward exploratory bioactivity detection rather than mechanistically grounded pharmacological development. In Bombax, several biological properties have progressed beyond this stage into validated in vivo models supported by biochemical and histological endpoints, suggesting a more advanced position along the preclinical validation continuum. In contrast, Pseudobombax remains predominantly positioned in early investigative phases, with activities frequently lacking systemic confirmation, molecular target identification, or pharmacokinetic characterization. Although both genera exhibit methodological limitations in extract standardization and pathway-level analysis, these constraints are more structurally limiting for Pseudobombax, where foundational translational infrastructure remains insufficiently developed.

In this context, a critical limitation across the available studies is the predominant reliance on in vitro experimental approaches, particularly for antioxidant, antimicrobial, and cytotoxic activities. While these assays are valuable for initial screening and hypothesis generation, they inherently lack physiological complexity. Chemical-based assays such as DPPH, ABTS, and FRAP measure the capacity of compounds to neutralize synthetic radicals under controlled conditions, which does not necessarily reflect their behavior in biological systems [53]. In vivo, redox homeostasis is regulated by complex enzymatic and non-enzymatic defense networks, and antioxidant activity is frequently mediated through modulation of endogenous pathways rather than direct radical scavenging. Therefore, the extrapolation of in vitro antioxidant activity to physiological or clinical efficacy remains limited and should be interpreted with caution [54].

From a phytochemical perspective, an important limitation of the current literature lies not only in the incomplete chemical profiling of Bombax and Pseudobombax species, but also in the insufficient pharmacological exploration of identified compounds. Although several bioactive metabolites, including mangiferin, flavonoids, and triterpenoids, have been reported, most studies attribute biological effects to broad chemical classes rather than to individual compounds [55]. This limits mechanistic interpretation and weakens the translational relevance of the findings.

Advancing this field will require a shift toward compound-oriented research approaches, prioritizing bioassay-guided fractionation, isolation of active constituents, and validation of molecular targets. Such strategies are essential to move beyond descriptive phytochemistry and establish robust chemical–biological relationships that support drug discovery efforts.

Similarly, antimicrobial and antiviral activities reported for these genera are largely supported by in vitro growth inhibition or cell-based assays, which do not account for critical determinants of therapeutic efficacy, such as pharmacokinetics, tissue distribution, host–pathogen interactions, and immune system modulation. Moreover, in vitro cytotoxicity assays often lack selectivity assessments against non-tumoral cells and are not supported by in vivo tumor models, further restricting their translational relevance [56]. Collectively, these limitations highlight a substantial gap between experimental bioactivity detection and clinically meaningful outcomes.

Collectively, this asymmetry delineates two distinct developmental trajectories. Bombax represents a genus with consolidating pharmacological credibility that now requires deeper mechanistic refinement and chemical standardization to sustain translational progression. Pseudobombax, in contrast, emerges as a largely untapped phytochemical reservoir situated at the threshold of systematic exploration. Advancing the field will require a deliberate transition from repetitive exploratory screenings toward integrated, mechanism-oriented investigations combining phytochemical fingerprinting, target-based validation, and pharmacokinetic assessment. Expanding taxonomic coverage beyond B. ceiba, implementing comparative organ profiling, and strengthening molecular-level confirmation are essential to transform descriptive evidence into clinically meaningful insight.

Ultimately, the current body of literature reflects not the full pharmacological potential of Bombax and Pseudobombax, but rather the limitations of prevailing investigative paradigms. Bridging this gap demands a strategic reorientation from exploratory abundance to mechanistic precision. Only through such a shift can these genera transition from ethnopharmacological relevance to evidence-driven candidates within the modern drug discovery framework.

5. Conclusions

This narrative review provides a comprehensive and hierarchically structured appraisal of the pharmacological evidence available for the genera Bombax and Pseudobombax, revealing a pronounced asymmetry in research depth, taxonomic coverage, and translational maturity. While Bombax, particularly B. ceiba, exhibits a relatively advanced preclinical evidence profile supported by validated in vivo models and biochemical endpoints, the genus remains heavily centralized around a single species, limiting broader phytochemical and pharmacological generalization. In contrast, Pseudobombax is positioned at an earlier stage of scientific development, with most activities confined to exploratory or functionally descriptive investigations that lack mechanistic and pharmacokinetic refinement.

Across both genera, antioxidant activity predominates; however, it is largely anchored in chemical assays with limited physiological correlation, highlighting a persistent translational gap between in vitro screening and clinically relevant validation. Additionally, the preferential investigation of specific plant organs, particularly stem bark and flowers, reflects methodological and ethnobotanical influences rather than systematic phytochemical comparisons, raising both scientific and sustainability concerns regarding plant survival.