Anacardium Humile Research Articles

Pseudoplagiostoma humilis sp. nov., a New Fungal Species CausingShoot Blight and Dieback in Anacardium humile in Brazil.

The cajuzinho do cerrado (Anacardium humile-Anacardiaceae), a shrub species native to Brazil, is harvested for multiple uses in food and medicine. Members of a harvesting community, near the municipality of Bonito de Minas, Minas Gerais state, Brazil reported characteristic symptoms of shoot blight and dieback reducing pseudofruit and seed production by this plant. This study aimed to identify the etiological agent of this disease. Two fungal isolates were obtained from symptomatic leaf samples and morphologically and molecularly characterized. The fungus was identified, based on morphological analyses, as a probable new species of Pseudoplagiostoma. Phylogenetic analyses based on a combination of DNA sequence data (nuc rDNA ITS1-5.8S-ITS2 region, tef1-α and tub2), confirmed this hypothesis. The isolates obtained were allocated to a distinct, well-supported clade (IB = 0.99, ML = 100%), placed as a unique lineage here proposed as a new species named Pseudoplagiostoma humilis. The pathogenicity test confirmed that this new species was the causal agent of shoot blight and dieback on A. humile. This is the fourteenth Pseudoplagiostoma species reported in the world and the third in Brazil.

Diversity of insect galls in veredas of the Brazilian Cerrado in Minas Gerais, Brazil

Brazilian veredas are hygrophilous communities with high species diversity, featuring many floristic studies but a still incipient number of faunistic studies. In the present study, we conducted an inventory of insect galls in four different veredas located in the Northern region of Minas Gerais, Brazil. Overall, we found 75 gall morphotypes, distributed across 50 host species representing 37 plant genera and 22 families. Fabaceae was the plant family with the greatest number of insect gall morphotypes (n = 21), followed by Malpighiaceae (n = 10). The plant genera that supported the highest diversity of insect galls were Copaifera (n = 8) and Byrsomima (n = 5). The plant species Copaifera oblongifolia (n = 6) and Anacardium humile (n = 4) exhibited the highest richness of insect galls. The leaves were the most attacked organs (89% of all galls). Most morphotypes are glabrous (83%), green (69%) and lenticular (60%). The taxa of gall-inducing insects were identified for 46 morphotypes (80%), and were recorded inducers from the orders Diptera, Lepidoptera, and Hymenoptera. Cecidomyiidae (Diptera) was the most representative galling group, with 42 morphotypes, making up 93.3% of the recorded inducers. Among the sampled veredas areas, the Vereda do Peruaçu presented the highest richness of insect gall morphotypes and host plant species. The faunistic similarity was higher in the Pedras and Tiririca veredas, followed by Almescla and Peruaçu veredas. This is the first systematic inventory of insect galls and their host plant in Brazilian veredas. The diversity of insect galls in the studied veredas is relatively high when compared to other Brazilian Cerrado vegetation types.

Application of response surface methodology in the characterization and sensorial analysis of Anacardium humile liqueur

Anacardium humile, known as “cajuzinho-do-cerrado,” is a native Brazilian Cerrado fruit similar to the cashew but less studied, particularly its phenolic compound content and profile. This study used a factorial design to examine how A. humile concentration and maturation time affect the liqueur's physicochemical attributes, phenolic content, antioxidant capacity, and sensory appeal. The liqueurs exhibited low antioxidant capacities as determined by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity assay (DPPH), ferric ion reducing antioxidant power (FRAP), and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid). This is likely attributable to a reduction in phenolic compounds within the liqueurs compared to A. humile. The phenolic compound profile of A. humile showed 11 compounds, comprising 5 flavonols, 3 hydroxycinnamic acids, and 2 hydrolyzable tannins. Treatment 8 (500 g of A. humile and 17 days of maturation) showed the highest value for phenolic compound content. However, with regard to sensory analysis, this was the darkest liqueur and the least accepted test, while Treatment 5 (147.5 g of A. humile and 10 days of maturation) was one of the most accepted and chosen as the best liqueur due to the highest antioxidant capacity by FRAP and DPPH methods. The fusion of technology and factorial design proved efficacious in formulating functional liqueurs.

Mass spectrometry-based untargeted metabolomics approaches for comprehensive structural annotation of bioactive metabolites from bushy cashew (Anacardium humile) fruits

Anacardium humile (bushy cashew) is a native Brazilian plant with substantial pharmacological potential and noteworthy commercial significance in the food industry. This study introduces an untargeted metabolomics approach based on mass spectrometry for the comprehensive structural annotation of bioactive metabolites. The fruits were collected from three distinct sites and subjected to LC-HRMS/MS analysis. A total of eighty-eight compounds were putatively annotated across various metabolite classes. This unveiled a metabolic profile characterized by notable concentrations of polyphenols, including flavonoids, tannins, phenolic acids, and quinones, while aliphatic acids and terpenes were found in limited quantities. Noteworthy, no significant disparities in the metabolic content were observed among the collection sites. The three principal metabolites (peonidin 3-O-glucopyranoside, methylcyanidin and methyldelphinidin) underwent assessment for antioxidant activity via molecular docking analysis, subsequently generating structure-based feature pharmacophores. The process of annotation propagation yielded a comprehensive qualitative appraisal of the A. humile metabolome. The outcomes obtained offer potential candidates for further exploration of their nutraceutical attributes.

Fire seasonality plays a limited role in the reproduction of Anacardium humile A. St.-Hil. in a tropical savanna.

Anthropogenic fires are an increasing threat to tropical savannas and their plant populations. In the Brazilian Cerrado, human-made fires at the end of the dry season are replacing natural fires at the beginning of the dry season. Critically, these late burns occur under more intense climate variables. Here, we aimed to understand the potential role of fire seasonality on individuals of Anacardium humile, a widespread Cerrado species of cultural and economic importance. We conducted two prescribed burnings, one at the beginning of the dry season (early burning) and one at the end of the dry season (late burning) when climate variables were remarkably different. We assessed the reproductive responses of A. humile individuals over 4 years and compared individuals from the fire treatments with those from an unburned area (control). The reproductive phenology of A. humile varied over time and was influenced by climate variables. The seasons of different burning had similar impacts on the reproductive phenology of A. humile, and this impact lasted for at least 4 years. While A. humile populations do not depend on fire for reproduction, they produced more flowers and fruits for up to 2 years with the fire treatments. We provide empirical evidence of the role of climate variables on the phenology of A.humile and demonstrate the importance of considering the role of time after fire events. The similar responses of A. humile to fire seasonality show that Cerrado fire management can be more complex than previously thought.

Diversidade genética e estrutura de populações de Anacardium humile (Anacardiaceae)

Abstract The objective of this work was to describe and compare the patterns of genetic variation in 19 populations of Anacardium humile from the Cerrado biome of the Brazilian Midwestern region. The ex situ germplasm collection of Universidade Federal de Jataí, in the state of Goiás, Brazil, was used for the study. To quantify the genetic variability of A. humile, 529 plants from 17 populations in Goiás from 2 in the state of Mato Grosso were studied, from which nine microsatellite loci were genotyped by capillary electrophoresis. The populations showed high levels of genetic diversity, with an average value of 0.830, and high inbreeding values, which suggests a deficit of heterozygotes. The genetic differentiation value between populations was 0.065. The greatest variability, which is moderately structured, was observed within populations. There is a significant inbreeding within the A. humile population in the Cerrado biome of the Brazilian Midwestern region. The A. humile populations are divided into two groups.

Galhas de insetos da Serra da Bandeira (Barreiras, Oeste da Bahia, Brasil)

Abstract Understanding the diversity of insect galls is pivotal to the establishment of conservation planning in different Brazilian ecosystems. Here, we (1) characterize the insect galls found on plant host species, (2) identify the gall-inducing insects to the lowest possible taxonomic level, and (3) record the presence of gall-associated fauna. Our study was carried out monthly from August, 2017 to July, 2018 along nine trails in Serra da Bandeira, which is located in an area of Cerrado stricto sensu over a year. We found 48 distinct gall morphotypes, belonging to 12 botanical families. The most morphotypes commonly found were globoid (27.1%), lenticular (27.1%) and cylindrical (25%). The plant organs most affected by galling insects were the leaves (73%), followed by the stem (19%), flower (4%), inflorescence (2%) and fruits (2%). The host botanical families holding the highest number of galls were Fabaceae (26), Malpighiaceae (5) and Anacardiaceae, Combretaceae and Euphorbiaceae (3). We observed that the genus Copaifera Lindl. (Fabaceae) had the greatest diversity of gall morphotypes, harboring 19 morphotypes distributed in three species that occur sympatrically - Copaifera sabulicola J. Costa (Fabaceae), Copaifera depilis Dwyer (Fabaceae) and Copaifera luetzelburgii Harms (Fabaceae). For the first time in Brazil, we recorded the occurrence of galls on flowers of Manihot caerulescens (Euphorbiaceae), on inflorescences of Mimosa acutistipula (Fabaceae) and flower buds of Anacardium humile (Anacardiaceae), which were induced by Cecidomyiidae. Inducers of the order Diptera (Family Cecidomyiidae) were the most abundant, found in 14 morphotypes of galls. Regarding the associated fauna, we found insects primarily belonging the order Hymenoptera, and identified them as parasitoids. The information provided can be used highly by decision makers for conservation programs, as well as in other strategies for the conservation of biological diversity in the Brazilian Cerrado.

Intraspecific variation in ultrastructure and secretion of the resin canals in Anacardium humile (Anacardiaceae).

The study combines a range of light and electron microscopy methods to access variation in secretion and ultrastructure in the secretory canals in the above- and belowground stems of Anacardium humile, which here serves as a model system. The aboveground stem canals show epithelial cells with ultrastructural characteristics typical of cells active in secretion, while in the belowground stems, the subcellular characteristics are typical of cells with low rates of metabolism. The secretory canals of the belowground stems show uniformity in size and shape, a large central vacuole, a cytoplasm reduced to a thin layer at the cell periphery, and a reduced population of organelles. The aboveground stem canals had voluminous nuclei with evident nucleoli, a very dense cytoplasm with free ribosomes, polyribosomes, mitochondria with developed cristae, and ellipsoid plastids with electron-opaque droplets surrounded by a periplastid reticulum. The vacuoles were of different sizes and often had membranous contents and the dictyosomes were very developed with dilated ends to the cisternae, rough endoplasmic reticulum, and numerous vesicles. The results show that particularities in above- and belowground environment have significant implications for ultrastructural morphology and functioning of secretory canals in the stems of A. humile.

New Therapeutic Perspective Based on Anacardium humile in the Treatment of Skin Wound Infected by Staphylococcus aureus

This is a literature review with the objective of presenting scientific evidence about the therapeutic importance of the use of Anacardium humile for the treatment of infected skin wounds. Retrospective and analytical study carried out from 1999 to 2021, in the Bireme, UpToDate, Pubmed and Scielo databases. The association of the descriptors “Phytotherapy” was used; “Cerrado and Pantanal Plants”; “Wounds contaminated by bacteria”; “elastic fibers”. Of the 248 articles analyzed, 36 were included in the review because they met the inclusion criteria. Among the results, it was evidenced that the conventional treatments, although effective (the gold standard being Sulfadiazine 1% silver), present toxicity to human keratinocytes and fibroblasts, with this, it is concluded that further research will be necessary to prove the effectiveness of new treatment options or association of herbal medicines with treatment.

Viability and Vigor of Cerrado Cashew Seeds (Anacardium humile) on Different Substrates

The little cashew from the Cerrado (Anacardium humile) is a kind of family anacardiáceaceas, a shrubby plant of great incidence in the Brazilian Cerrado. It is a small pseudofruit, of acidic and juicy flavor, which is known to have colors ranging from yellow to red. It can be consumed naturally or in juices, drinks, sweets. However, its true fruit is the chestnut. Seed germination is influenced by factors such as the substrate, which can be improved in order to improve germination, resulting in the acquisition of more vigorous seedlings. The experiment was conducted in a greenhouse at the Federal Institute of Education, Science and Technology of Tocantins, city of Gurupi/TO, from 26 October 2017 to 15 February 2018. Seeds were collected directly from the pseudofruits. The highest root length value was obtained for seedlings of the following substrates: bs + ws + pb (7.1 cm and 12.5 cm) and ws (6.7 cm and 10.7 cm), intermediate values: or + rs + vl (6.3 cm and 10.0 cm) and hw + vl + sawdust + cp + ws (5.5 cm and 9.5 cm), and lower values on substrates: bs (5.7 cm and 8.0 cm) and bs + rs + sawdust (6,6 cm e 9,0 cm). It was also observed that the highest value referring to the first emergency count and seedling emergence once again stood out the substrates bs + ws + pb (61.0 % and 87.5 %) and ws (56.2% and 86.2 %). Intermediate results were obtained from hw substrates + vl + sawdust + cp + ws(44.0 % and 81.0 %) and or + rs + vl (48.4 % and 81.2 %) and lower for bs substrates (37.5% and 72.0 %) and bs + rs + sawdust (45.3% and 77.0 %). The substrates: bs + ws + pb and washed sand provided the highest values of viability and vigor in cashew seeds.

Doses of limestone, phosphorus and potassium on the initial development of Anacardium humile seedlings

The objective of this work was to evaluate the effect of different doses of limestone, phosphorus, and potassium on the initial development of Anacardium humile (Cajuzinho-do-cerrado) seedlings. The experiment was conducted in a greenhouse. A randomized block design was adopted in a 3x4x4 factorial scheme (liming x phosphorus x potassium doses). The treatments consisted of three liming doses (0; 40; and 70% of base saturation), four doses of potassium chloride with 60% of K2O (0; 60; 120; and 180 kg ha-1), and four doses of triple superphosphate with 46% of P2O5 (0; 80; 160; and 240 kg ha-1), with six replications. The following characteristics were evaluated: stem diameter (SD), plant height (PH), root length (RL), shoot dry matter (SDM), and root dry matter (RDM). The data were submitted to analysis of variance and the averages were compared by Tukey’s test (p < 0.05). It was concluded that there was no influence of phosphorus doses on the initial development of A. humile seedlings and that there was a response to the association between liming and potassium chloride in vegetative growth.

Gallic acid anti-myotoxic activity and mechanism of action, a snake venom phospholipase A2 toxin inhibitor, isolated from the medicinal plant Anacardium humile

Snakebite envenoming is the cause of an ongoing health crisis in several regions of the world, particularly in tropical and neotropical countries. This scenario creates an urgent necessity for new practical solutions to address the limitations of current therapies. The current study investigated the isolation, phytochemical characterization, and myotoxicity inhibition mechanism of gallic acid (GA), a myotoxin inhibitor obtained from Anacardium humile. The identification and isolation of GA was achieved by employing analytical chromatographic separation, which exhibited a compound with retention time and nuclear magnetic resonance spectra compatible with GA's commercial standard and data from the literature. GA alone was able to inhibit the myotoxic activity induced by the crude venom of Bothrops jararacussu and its two main myotoxins, BthTX-I and BthTX-II. Circular dichroism (CD), fluorescence spectroscopy (FS), dynamic light scattering (DLS), and interaction studies by molecular docking suggested that GA forms a complex with BthTX-I and II. Surface plasmon resonance (SPR) kinetics assays showed that GA has a high affinity for BthTX-I with a KD of 9.146 × 10−7 M. Taken together, the two-state reaction mode of GA binding to BthTX-I, and CD, FS and DLS assays, suggest that GA is able to induce oligomerization and secondary structure changes for BthTX-I and -II. GA and other tannins have been shown to be effective inhibitors of snake venoms' toxic effects, and herein we demonstrated GA's ability to bind to and inhibit a snake venom PLA2, thus proposing a new mechanism of PLA2 inhibition, and presenting more evidence of GA's potential as an antivenom compound.

Structural assessment of a population of Anacardium humile subjected to fire during different periods of the year

ABSTRACT Understanding how fire affects the plant biota of the Cerrado is essential for formulating conservational strategies. We evaluated the effects of fires during different periods of the year on the populational structure of Anacardium humile. The research was carried out in areas of typical cerrado stricto sensu in the territory of the Kalunga, state of Goias, Brazil. These areas, which comprise the same population, were submitted to the following treatments: unburned (control), burned in May 2016 (early fire - EF), and burned in September 2016 (late fire - LF). In July 2018, we delimited two contiguous transects of 100 x 20 m, subdivided into 10 plots of 20 x 20 m, in each area. Fire stimulated the development of branches from basal regrowth in EF and LF. No differences were found in height and diameter of individuals among LF, EF, and the control area. Individuals of EF had size patterns similar to the control individuals, indicating a lesser effect of early fire. The greatest differences regarding all significant parameters were found between LF and control individuals. Early prescribed fires, depending on periodicity, may be less harmful to A. humile.

(2730) Proposal to conserve the name Anacardium humile against A. mediterraneum (Anacardiaceae)

(2730) Proposal to conserve the name <i>Anacardium humile</i> against <i>A. mediterraneum</i> (<i>Anacardiaceae</i>)

Leaf area estimation of Anacardium humile

Abstract The Anacardium humile A. St.- Hil. fruit tree has productive potential, being their fruits appreciated in the Cerrado region for having characteristic flavor, however, this species is still exploited in an extractive way, being necessary studies for its domestication. The aim of this work was to estimate the leaf area of Anacardium humile. One hundred leaves were collected in the biological collection from a genetic resources field and evaluated for length, width and fresh weight, and scanned at resolution of 300 dpi to determine the leaf area with the aid of the ImageJ image analysis program. Subsequently, a leaf disc with a diameter of 22.27 mm was detached at the basal portion of each leaf, in which the fresh weight of the discs was obtained. Data were submitted to descriptive analysis and the relationship among the features explained by Pearson’s correlation with the software Rbio. The data were also subjected to regression analysis to explain the relationship between leaf area and measurements of width, length and leaf weight, and to fit the proper statistical model with the software Origin. It was concluded that leaf area can be determined by image analysis software and linear measurements are correlated to leaf area.

Chemical profile and allelopathic potential of Anacardium humile St. Hill. (cajuzinho-do-cerrado) leaf aqueous extract in the seed germination and seedling growth of lettuce, tomato and sicklepod

Anacardium genus, Anacardiaceae, stands out for the presence of phenolic compounds. One of its species, investigated for its different potential uses, is Anacardium humile; however, little is known about its allelopathic effects. Therefore, the present study aimed to determine the chemical profile and evaluate the herbicide potential of your leaves in the germination of seeds and growth of seedlings of Lactuca sativa (lettuce), Lycopersicon esculentum (tomato) and Senna obtusifolia (sicklepod), both in vitro and in greenhouse. Leaves of A. humile were obtained from 20 matrices of Cerrado fragments in the municipality of Campo Grande, Mato Grosso do Sul state, Brazil. A voucher specimen was deposited at the herbarium (no. 8448). The aqueous extract was obtained from dried and crushed leaves using the extraction method of ultrasonic bath (30 min) with subsequent static maceration. After solvent evaporation, 12.78 g of extract were obtained. The chemical profile of the aqueous extract included determination of total phenolic and flavonoid contents, pH, electrical conductivity, and soluble solids concentration. For the in vitro bioassays, the extract was used at different concentrations, namely, 25, 50, 100, 150, and 200 mg mL-1. In greenhouse, the substrates were prepared using 950 g of vermiculite and 50 g of A. humile leaf powder at the following ratios: (950/50) (5%), 900/100 (10%), 800/200 (20%), and a control (100% vermiculite), under a completely randomized experimental design. Phenolic compounds and anthraquinones were predominant in the chemical profile of the extract, which presented different levels of allelopathic effect on seed germination and seedling growth of plants both in germination chamber and in greenhouse, indicating strong allelopathic activity associated with the different compounds found in the leaves. Therefore, the results showed germination and growth inhibition at different levels, indicating that the substances contained in the leaves of Anacardium humile may be a promising alternative for the control of invasive species.

Detection of Colletotrichum gloeosporioides in native cashew species in Brazil.

The savanna cashew (Anacardium humile A. St. Hil.) nut is a native shrub species distributed in the savanna biome of Central Western Brazil. This species is similar to the cashew (Anacardium occidentale L.) nut, and its edible pseudo-fruits have been used for various purposes. However, A. humile is at risk of extinction. One reason for this is the phytosanitary issues. Therefore, phytosanitary studies of the serious plant diseases caused by fungal pathogens are necessary. The aim of this study was to survey the savanna cashew nut (Anacardium humile) in Central Western Brazil from August 2013 to October 2014. Serious damage caused by anthracnose to the plant's leaves and fruits was consistently detected. The pathogen fungal species was Colletotrichum gloeosporioides. It was identified by morphological characteristics and molecular analyses. Additional experiments showed evidence that C. gloeosporioides can be transmitted by cashew seeds. We observed anthracnose symptoms on the surfaces of the floral peduncle, leaves, and peduncle of the A. humile cashew nuts. The genomic DNA sequences of the selected strains for molecular characterization have had 99% identity with the analogous sequences of C. gloeosporioides. Naturally occurring C. gloeosporioides infection of the leaves of A. humile was low (20.3%) compared with that of the nuts (79.7%). Our results can be used to design strategies to prevent the introduction and establishment of C. gloeosporioides in new areas. They can also be helpful in monitoring programs in areas with a current occurrence of C. gloeosporioides. Finally, these results can be used in future research plans of C. gloeosporioides infection management.

Characterization of Bushy Cashew (Anacardium humile A. St.-Hil.) in the State of Goiás, Brazil

The physical and chemical characteristics of the fruits influence the consumer acceptance. The objective of this study was to perform the physical, physico-chemical and chemical characterization of fruits of accessions of bushy cashew (Anacardium humile A. St.-Hil.) (cashew nut and cashew apple) in a germplasm bank located in southwest of the state of Goi&amp;aacute;s, in Brazil, aiming at the selection of superior accessions, in order to facilitate the initiation of a program to encourage the production and consumption, for provide information for breeding programs and the specie preservation. This research study was conducted at the Laboratory of genetics and molecular biology with material collected in the Experimental Station of the Federal University of Jata&amp;iacute;, within the biological ex situ collection of Anacardium humile, in the field of genetic resources. In the harvest of 2016, within this collection, they were evaluated accesses for the characteristics of the cashew apple: length, diameter of base, apex diameter, weight, instrumental coloration of the epidermis and pulp, titratable acidity (citric acid), vitamin C content (ascorbic acid) and carotenoid content; cashew nut were evaluated: length, width, thickness and weight. The results were submitted to descriptive analysis, obtaining average, minimum, maximum and variation coefficient and the correlation between the variables, testing the significance by the t test. Most of the accesses showed high CV for most of the variables, demonstrating high heterogeneity of the observed values. Cashew apples have high levels of vitamin C and carotenoids, indicating the nutritional potential of the specie.

Cryopreservation as an alternative for conservation of Anacardium humile achene (Monkey nut)

The present study aimed to evaluate the possibility of using cryopreservation method for conservation of cajuzinho-do-cerrado achene (Anacardium humile). To accomplish this aim, the physiological quality of cryopreserved achenes was compared with the quality of samples stored under other conditions. The quality of cryopreserved achenes with different water contents was also evaluated to establish a water-content limit for seed-viability maintenance. Achenes with physiological maturity were stored in liquid nitrogen at -196 degreesC with the following water contents: 28 (initial content) 14, 12, 8 and 5% moisture content (mc). Subsequently, the achenes were subjected to 3 thawing methods: slow/gradual, fast and microwave thawing. Achenes were also subjected to different six conservation methods: cryopreservation in liquid nitrogen (LN) at -196 degreesC, cryopreservation using 10% cryoprotectants (Dimethyl sulfoxide (DMSO) or Glycerol), 10 degreesC biochemical oxygen demand (BOD) incubator, -80 degreesC ultra-low freezer and room temperature (25 degreesC +-3), with testing after storage in these environments for 5 and 10 months. The treatment effect on achene, physiological quality was assessed by seed germination (percentage) and vigour (germination speed index, electrical conductivity and root and shoot length). The results showed that reduction in the water content considerably reduced the germinating potential of 'Anacardium humile' achenes for cryopreservation. Conversely, the thawing methods had no effect on the physiological quality of cryopreserved achenes; thereby, allowing the choice of the most practical thawing method (microwave). We also concluded that cryopreservation in liquid nitrogen may be used as a viable alternative for conservation of 'Anacardium humile' achene.

Osmophores and floral fragrance in Anacardium humile and Mangifera indica (Anacardiaceae): an overlooked secretory structure in Sapindales.

Flowers of Anacardiaceae and other Sapindales typically produce nectar, but scent, often associated with a reward for pollinators, has surprisingly been mentioned only rarely for members of the family and order. However, flowers of Anacardium humile and Mangifera indica produce a strong sweet scent. The origin and composition of these floral scents is the subject of this study. Screening of potential osmophores on the petals and investigations of their anatomy were carried out by light, scanning and transmission electron microscopy. The composition of the floral fragrance was characterized by gas chromatography–mass spectrometry. In both species, the base of the adaxial side of each petal revealed specialized secretory epidermal cells which are essentially similar in structure and distinct from all other neighbouring cells. These cells also showed evidence of granulocrine secretory mechanisms and slight specific variations in their subcellular apparatus coinciding with the respective composition of the floral fragrance, predominantly composed of sesquiterpenes in A. humile and monoterpenes in M. indica. This study reports the presence of osmophores for the first time in flowers of Anacardiaceae and confirms the link between the ultrastructural features of their secretory cells and the volatiles produced by the flowers. The flowers of most Sapindales, including Anacardiaceae, are nectariferous. However, the presence of osmophores has only been described for very few genera of Rutaceae and Sapindaceae. Both the occurrence of osmophores and fragrance may have largely been overlooked in Anacardiaceae and Sapindales until now. Further studies are needed to better understand the nature and diversity of the interactions of their nectariferous flowers with their pollinators.