Tetragonisca Angustula Research Articles

Metabolomics analysis of (Geo)propolis from Brazilian stingless bees by FIA and UHPLC-HRMS (Orbitrap)

Native stingless bees (Meliponini) from Brazil make (geo)propolis which is largely used in folk medicine, specially by indigenous and quilombos communities and beekeepers´ families but are progressively being recognized for their pharmacological activities. In this study, the ethanolic extracts of (geo)propolis (EEGs) from Melipona marginata, M. quadrifasciata, M. scutellaris, and Tetragonisca angustula were analysed by Flow injection analysis (FIA) and Ultra-high performance liquid chromatography (UHPLC) in a high resolution Orbitrap mass analyser (HRMS) to investigate and compare their chemical profile. Untargeted metabolomic approach based on UHPLC-HRMS experiments, and bioinformatic tools, allowed to annotate 59 compounds from diverse classes such as: flavonoids, phenolic compounds, sugars, terpenoids, and lipids. In addition, using multivariate tools and Flow injection- high resolution mass spectrometry (FIA-HRMS), it was possible to classify samples and identify marker ions related to the bee species or genus and to the geographical origin as a proof of concept.

Assessing ecosystem resilience: effects of different environments on native flora, lichens and bee pollen in a mid-sized Brazilian city

Abstract The alteration of the natural environment by human activities has increased in recent decades, with a significant impact on the organisms that inhabit it. One of the most apparent consequences of environmental alterations is the occurrence of climatic changes. The city of Joinville is situated in the southern region of Brazil. It has achieved a notable position at the national level, largely due to the significant presence of large-scale industrial operations in the metal-mechanical, plastic, and textile sectors. This study aimed to assess the effects of urban environments on Nectandra oppositifolia plants and lichen communities using a passive biomonitoring approach, and on Tetragonisca angustula stingless bees using an active biomonitoring approach. This study demonstrated a pronounced effect of anthropogenic activities on plant anatomy and morphology (higher leaf area, fresh mass, dry mass, and water content in the urban-industrial site), with higher metal concentrations in leaf particulate matter (3.14 ± 0.4 μg cm−2). The diversity of lichens was the lowest, whereas that of crustose lichens was the highest in industrial-urban and residential-rural sites (industrial-urban site = 13 species, residential-rural site = 29 species, control site = 33 species, p < 0.05). The distribution of species within the lichen communities was inversely correlated with the degree of anthropogenic influence. Some lichen species were found exclusively in the control areas, suggesting that they may indicate good environmental quality (Arthonia sp., Astrothelium sp., Phyllopsora pyxinoides, Phyllopsis sp., and others). Beehive pollen analysis revealed the presence of Zn, Cr, Ni, Cu, and Pb, and industrial-urban site exhibited higher metal concentrations (particularly, Ni, 12.59 ± 0.9, and Cr, 3.76 ± 1.00, mg kg−1). This approach highlights the environmental repercussions that affect the Plantae, Fungi, and Animalia kingdoms. The use of biomonitoring as a robust tool in good environmental quality assessment provides insight into policy decisions and underscores the importance of pollution studies.

Neonicotinoids, Agriculture And Food Security Of Brazilian Honey: A Review

Pesticides used in agriculture have the function of controlling pests, diseases and preventing the development and growth of weeds, increasing the quality and productivity of crops. However, when they reach unwanted targets, such as bees, humans and other living beings, they cause harmful damage to ecosystems. Neonicotinoids, insecticides widely used in monocultures, such as soybeans and corn in Brazil, are especially harmful to bees, whether native or exotic, interfering with the foraging and pollination performance of plants. The global decline in the bee population is related to the use of insecticides, a fact that directly threatens the production of various foods. Honey, the main beekeeping product , is not only a source of food for bees, humans and other animals, but also an indicator of environmental quality, as its composition reflects the conditions of the environment in which it was produced, and determinations made therein can reveal the presence of contaminants such as pesticides and toxic metals providing information about ecosystem health and the presence of environmental contaminants. Furthermore, consuming pesticide-free foods is crucial for human health and environmental sustainability, as the intake of neonicotinoids is associated with several health problems such as hormonal disorders and nervous system diseases and is especially dangerous for children. This article reviews the neonicotinoid insecticides imidacloprid and thiamethoxam and the contamination they cause in the honey of bees Apis mellifera Linnaeus (1758) and Tetragonisca angustula Latreille (1811) in Brazil, evaluating the impacts of these insecticides on bees, the implications for ecosystems and safety to feed

Toxicity of botanical insecticides on the stingless bee Tetragonisca angustula

This study aimed to investigate the toxicity of botanical insecticides on the stingless bee Tetragonisca angustula (Apidae: Meliponini). Bioassays evaluated the effects of essential oils (EO) of Allium sativum (Amaryllidaceae), Eucalyptus citriodora (Myrtaceae), and commercial oil (CO) of Azadirachta indica (Meliaceae), in addition to ethanolic extracts (EE) of Piper nigrum (Piperaceae), and Eugenia caryophyllata (Myrtaceae). It was also assessed the effect of Surfactant addition to essential oils. The probit analysis was used to determine LC50 and LC90. Results showed essential oil of E. citriodora at 1% v/v was toxic to T. angustula, with mean mortalities of 42.00 and 46.00% at 96 hours and survival times of 107.52 and 105.60 hours for contact and ingestion, respectively. Ethanolic extracts of P. nigrum and E. caryophyllata caused 100% mortality within 24 hours through ingestion but were less toxic through contact. Surfactants increased mortality caused by the essential oil of E. citriodora from 47.67 to 93.33% and the commercial oil of A. indica from 38.00 to 100%. Essential oil of E. citriodora had the lowest LC50 and LC90 (0.075 and 1.45% v/v), indicating high toxicity to T. angustula. Ethanolic extracts of P. nigrum and E. caryophyllata had higher LC50 and LC90 values, showing lower toxicity. In conclusion, the oils of A. indica and E. citriodora and ethanolic extracts of P. nigrum and E. caryophyllata are toxic to stingless bee T. angustula.

Inhibitory Activity of Propolis Extracts From Stingless Bees (Meliponini) on the Development of Phytopathogenic Fungi: in Vitro Evaluation

Objective: The present study aimed to assess the alcoholic extracts of propolis from Tetragona clavipes, Scaptotrigona bipunctata, Tetragonisca angustula, and Melipona quadrifasciata. Theoretical Framework: There is growing interest in the bioactive metabolites of propolis and honey produced by different species of the group of native stingless bees (NSB) belonging to the Meliponini tribe. Method: The extracts were prepared in a proportion of 30 g of propolis to 70 mL of 96 % v/v ethanol (1:2). Afterwards, its chemical constituents were characterized by HPLC. A PDA medium was used to evaluate the antifungal activity, with the extracts added to the melting medium (55 °C) in different concentrations. The effect of increasing concentrations (1.6 %, 3.2 %, 6.4 %, and 12.0 % v/v) of extracts on the mycelial growth of the fungi Sclerotinia sclerotiorum, Fusarium sp., Colletotrichum gloeosporioides, Botrytis cinerea, and Botryosphaeria sp. was evaluated. Fungal development was determined by measuring mycelial diameter on the 14th day of inoculation. Results and Discussion: The antioxidant activity and the contents of flavonoids and phenolic compounds were identified in all samples of propolis extracts from ANSF. The T. clavipes propolis extract had the highest content of phenolic compounds (5,593 mgEAG·100 mL-1). Among the chemical compounds, naringin, gallic acid, hesperidin, and ferulic acid were identified in greater quantities. The fungi evaluated in this work were partially inhibited by most SNB alcoholic extracts, mainly at concentrations of 1.6 % and 3.2 % v/v compared to the control treatment (ethanol 96 % v/v). Changes in the hyphal network and the reduction or absence of conidia were also observed when combined with different alcoholic propolis extracts and the control with 96 % v/v ethanol. Research Implications: The results demonstrate that the chemical components of the alcoholic extracts of NSB propolis have the potential for controlling phytopathogenic fungi of agricultural interest. Originality/Value: This study contributes by assessing and highlighting the potential applications of NSB as natural products in the alternative control of phytopathogenic fungi of agricultural interest.

Genome assembly and variant analysis of two Saccharomyces cerevisiae strains isolated from stingless bee pollen

Products from stingless bees are rich reservoirs of microbial diversity, including yeasts with fermentative potential. Previously, two Saccharomyces cerevisiae strains, JP14 and IP9, were isolated from Jataí (Tetragonisca angustula) and Iraí (Nannotrigona testaceicornis) bees, respectively, aiming at mead production. Both strains presented great osmotic and sulfite tolerance, and ethanol production, although they have a high free amino nitrogen demand. Herein, their genomes were sequenced, assembled, and annotated, and the variants were compared to the S. cerevisiae S288c reference strain. The final assembly of IP9 and JP14 presented high N50 and BUSCO scores, and more than 6430 protein-coding genes. Additionally, nQuire predicted the ploidy of IP9 as diploid, but the results were not enough to determine the ploidy of JP14. The mitochondrial genomes of IP9 and JP14 presented the same gene content as S288c but the genes were rearranged and fragmented in different patterns. Meanwhile, the genes with mutations of high impact (e.g., indels, gain of stop codon) for both yeasts were enriched for transmembrane transport, electron transfer, oxidoreductase, heme binding, fructose, mannose, and glucose transport, activities related to the respiratory chain and sugar metabolism. The IP9 strain presented copy number gains in genes related to sugar transport and cell morphogenesis; in JP14, genes were enriched for disaccharide metabolism and transport, response to reactive oxygen species, and polyamine transport. On the other hand, IP9 presented copy number losses related to disaccharide, thiamine, and aldehyde metabolism, while JP14 presented depletions related to disaccharide, oligosaccharide, asparagine, and aspartate metabolism. Notably, both strains presented a killer toxin gene, annotated from the assembling of unmapped reads, representing a potential mechanism for the control of other microorganisms population in the environment. Therefore, the annotated genomes of JP14 and IP9 presented a high selective pressure for sugar and nitrogen metabolism and stress response, consistent with their isolation source and fermentative properties.

Pollen morphology and reproductive biology of Calophyllum brasiliense Cambess. (Calophyllaceae)

Pollen morphology and the reproductive biology of Calophyllum brasiliense were investigated in Parque Estadual das Fontes do Ipiranga, São Paulo, Brazil. The study encompassed pollen analyses using light, scanning, and transmission electron microscopy. Additionally, we collected data on reproductive biology, main visitors/pollinators, fruit set, and seed germination. The species exhibits individuals with perfect flowers (hermaphrodites) as well as male individuals with staminate and perfect flowers. Flowering occurs in October and November, and flowers have diurnal anthesis and pollen as a floral resource. Pollen grains are monads of medium size, isopolar, oblate-spheroidal to prolate-spheroidal, 3-(4)-zonocolporate, with exine fossulate-perforate with supratectal microechini. Hermaphrodite individuals have the highest proportion of malformed pollen due to their reduced grain size. The pollen grains from the hermaphrodite individuals displayed a low viability (0.06%), while those from male individuals had higher viability (66.38% and 55.78% for perfect and staminate flowers, respectively). The stigma was receptive throughout the anthesis period. Cross-pollination between perfect flowers of male and hermaphrodite individuals resulted in 8.80% success in fruit set, but led to the development of one abnormal seedling. Cross-pollination between staminate flowers and perfect flowers of hermaphrodite individuals showed a 7.70% success rate and the control group showed an 8.00% success rate, both groups leading to the development of normal seedlings. This tree species shows relatively low reproductive success and relies on pollinators (mainly Apis mellifera, Paratrigona subnuda, Tetragonisca angustula, and Halictidae sp. 1) for the setting of fruits and seeds.

The nuclear and mitochondrial genome assemblies of Tetragonisca angustula (Apidae: Meliponini), a tiny yet remarkable pollinator in the Neotropics

BackgroundThe field of bee genomics has considerably advanced in recent years, however, the most diverse group of honey producers on the planet, the stingless bees, are still largely neglected. In fact, only eleven of the ~ 600 described stingless bee species have been sequenced, and only three using a long-read (LR) sequencing technology. Here, we sequenced the nuclear and mitochondrial genomes of the most common, widespread and broadly reared stingless bee in Brazil and other neotropical countries—Tetragonisca angustula (popularly known in Brazil as jataí).ResultsA total of 48.01 Gb of DNA data were generated, including 2.31 Gb of Pacific Bioscience HiFi reads and 45.70 Gb of Illumina short reads (SRs). Our preferred assembly comprised 683 contigs encompassing 284.49 Mb, 62.84 Mb of which (22.09%) corresponded to 445,793 repetitive elements. N50, L50 and complete BUSCOs reached 1.02 Mb, 91 contigs and 97.1%, respectively. We predicted that the genome of T. angustula comprises 17,459 protein-coding genes and 4,108 non-coding RNAs. The mitogenome consisted of 17,410 bp, and all 37 genes were found to be on the positive strand, an unusual feature among bees. A phylogenomic analysis of 26 hymenopteran species revealed that six odorant receptor orthogroups of T. angustula were found to be experiencing rapid evolution, four of them undergoing significant contractions.ConclusionsHere, we provided the first nuclear and mitochondrial genome assemblies for the ecologically and economically important T. angustula, the fourth stingless bee species to be sequenced with LR technology thus far. We demonstrated that even relatively small amounts of LR data in combination with sufficient SR data can yield high-quality genome assemblies for bees.

Green synthesis of silver nanoparticle using pollen extract from Tetragonisca angustula a stingless bee.

This study explores the green synthesis of silver nanoparticles (AgNPs) using a methanolic extract of fermented pollen from Tetragonisca angustula, a species of stingless bees. The AgNPs exhibit spherical morphology, low charge values, and suspension stability, with their unique composition attributed to elements from the pollen extract. Antioxidant assays show comparable activity between the pollen extract and AgNPs, emphasizing the retention of antioxidant effects. The synthesized AgNPs demonstrate antimicrobial activity against multidrug-resistant bacteria, highlighting their potential in combating bacterial resistance. The AgNPs exhibit no toxic effects on Drosophila melanogaster and even enhance the hatching rate of eggs. The study underscores the innovative use of stingless bee pollen extract in green synthesis, offering insights into the varied applications of AgNPs in biomedicine.

Stingless bee foragers experience more thermally stressful microclimates and have wider thermal tolerance breadths than other worker subcastes

IntroductionThe current state of anthropogenic climate change is particularly concerning for tropical insects, species predicted to be the most negatively affected. Researching climatic tolerance in social insects is challenging because adaptations exist at both individual and societal levels. Division of labor research helps to bridge the gap between our understanding of these adaptations at different scales, which is important because social insects comprise a tremendous portion of global animal biomass, biodiversity, and ecosystem services. Considering how individual physiologies construct group-level adaptations can improve climate change impact assessments for social species. Tetragonisca angustula is a neotropical stingless bee species that exhibits high worker subcaste specialization with a morphologically distinct soldier caste.MethodsWe used this species to investigate 1) whether age- and size-differentiated subcastes differ in thermal tolerance, 2) which worker subcaste operates closest to their thermal limits, and 3) the extent to which this species selects active foraging times to offset thermal stress. We measured the thermal tolerance (CTmax and CTmin) of small-bodied foragers and two soldier subcastes (hovering guards and standing guards) in T. angustula.Results and discussionDespite body size differences between foragers and guards, no differences in the upper or lower thermal limits were observed. However, the average thermal tolerance breadth of foragers was significantly larger than that of guards, and foraging sites were more thermally variable than nest sites, supporting the Climatic Variability Hypothesis at a microclimate scale and in the context of division of labor. Warming tolerance was significantly lower among small-bodied foragers compared to hovering and standing guards. The magnitude of warming tolerances indicated low risk of imminent climate change impacts in this environment but suggests that increasing temperatures and heatwave prevalence may cause foragers to meet their upper thermal limits before other subcastes. Foraging occurred at a narrower range of temperatures than would challenge critical temperatures, with higher morning activity. Directionally increasing temperatures will likely confine these preferred foraging temperatures to a narrower time window. Further study is needed to elucidate how foragers may shift times of activity in response to anthropogenic warming, but changing climates may impact plant pollination rates in natural and agricultural systems.

Evaluation of the anticoccidial effect of jataí bee (Tetragonisca angustula) propolis extract against Eimeria spp. oocysts in broiler

The use of anticoccidial compounds is the primary strategy for controlling avian coccidiosis. The emergence of drug resistance, regulatory restrictions, and societal demands for meat production without the use of antimicrobials have increased the need for natural alternatives to control this disease. Propolis is known for its antimicrobial effects and may be an alternative. In this context, this study aimed to evaluate the anticoccidial activity of jataí bee (Tetragonisca angustula) propolis against the sporulation of Eimeria spp. oocysts in broiler chicken feces. Propolis ethanolic extracts were tested at 10, 15, and 20% against Eimeria oocyst sporulation. Direct use of the extract on oocysts completely inhibited sporulation. When applied to feces, the extract significantly reduced the number of sporulated oocysts. Thus, the jatai bee propolis extract is a promising alternative to commercial anticoccidial agents.

Yeast Diversity in Honey and Pollen Samples from Stingless Bees in the State of Bahia, Brazil: Use of the MALDI-TOF MS/Genbank Proteomic Technique.

(1) Background: The identification of microorganisms includes traditional biochemical methods, molecular biology methods evaluating the conserved regions of rRNA, and the molecular biology of proteins (proteomics), such as MALDI-TOF MS mass spectrometry. This work aimed to identify the biodiversity of yeasts associated with stingless bee species' honey and pollen, Melipona scutellaris, Nannotrigona testaceicornes, and Tetragonisca angustula, from the region of São Gonçalo dos Campos-Bahia (BA) state, Brazil. (2) Methods: Cellular proteins were extracted from 2837 microbial isolates (pollen and honey) and identified via MALDI-TOF MS. The identified yeast species were also compared to the mass spectra of taxonomically well-characterized reference strains, available from the National Center of Biotechnology Information (NCBI) database. (3) Results: Nine yeast species were identified: Candida maltosa, Candida norvegica, Kazachstania telluris, Schizosaccharomyces pombe, Scheffersomyces insectosus, Meyerozyma guilliermondii, Brettanomyces bruxellensis, Kazachstania exigua, and Starmerella lactis-condensi. Nannotrigona testaceicornes pollen had the highest number of yeast colonies. The yeasts Brettanomyces bruxellensis and Kazachstania telluris showed high populations in the samples of Nannotrigona testaceicornes and Melipona scutellaris, respectively. This work shows that there is some sharing of the same species of yeast between honey and pollen from the same beehive. (4) Conclusions: A total of 71.84% of the identified species present a high level of confidence at the species level. Eight yeast species (Candida maltosa, Candida norvegica, Kazachstania telluris, Schizosaccharomyces pombe, Scheffersomyces insectosus, Meyerozyma guilliermondii, Kazachstania exigua, and Starmerella lactis-condensi) were found for the first time in the samples that the authors inspected. This contributes to the construction of new knowledge about the diversity of yeasts associated with stingless bee products, as well as to the possibility of the biotechnological application of some yeast species.

Antimicrobial activity of stingless bee honey (Tribe: Meliponini) on clinical and foodborne pathogens: A systematic review and meta‐analysis

AbstractHoney produced by stingless bees (Tribe: Meliponini) is well‐known for their medicinal and antimicrobial properties from their diverse content of bioactive compounds. However, it has not been possible to fully characterize its active principles. The present systematic review is based on 117 full‐text articles. Our review highlights (1) the need to apply complementary methodologies and consolidate protocols to quantify antimicrobial activity (2) to characterize antimicrobial agents in honeys of Heterotrigona itama, Tetragonisca angustula, and Melipona beecheii, and; (3) to search for compounds against multidrug‐resistant and/or biofilm‐forming pathogens. Moreover, we performed a meta‐analysis of 29 articles with quantitative data using diffusion assays and minimum inhibitory concentration (MIC). Staphylococcus aureus and Escherichia coli were the most evaluated pathogens, evidencing 221 and 149 antimicrobial activity assays against honey samples of 36 and 24 stingless bee species, respectively. The highest pooled mean in diffusion assays against S. aureus showed a difference between methicillin‐resistant S. aureus (MRSA) and non‐MRSA strains {14.43 [95% confidence interval (CI): 12.16–16.71] mm vs. 11.55 (95% CI: 10.22–12.87) mm}, whereas E. coli showed pooled means of 9.09 (95% CI: 7.93–10.25) mm. Regarding MIC expressed as volume/volume percentage (%, v/v), the estimated inhibitory concentrations were 7.89 (95% CI: 3.94–11.83) mL/100 mL for MRSA and 5.60 (95% CI: 2.66–8.55) mL/100 mL considering all S. aureus strains. In contrast, the estimated MICs as weight/volume percentage (%, w/v) showed 15.00 [(95% CI: 12.84–17.16) g/100 mL for S. aureus and 16.17 (95% CI: 5.78–26.55) g/100 mL for E. coli. However, honey remains an unexplored source of antimicrobial molecules.

Viruses in Brazilian stingless bees

Stingless bees are important pollinators in tropical and subtropical areas. The breeding of native stingless bee species from the Meliponini tribe to obtain honey, pollen, and geopropolis (meliponiculture) is a promising activity in Brazil with economic, social, and environmental impacts. Stingless bees can share food sources with Apis mellifera and other insects that can be vectors of pathogens. Here, we investigated seven stingless bee species from Brazil (Melipona quadrifasciata anthidioides, Melipona scutellaris, Nannotrigona testaceicornis, Partamona helleri, Scaptotrigona xanthotricha, Tetragonisca angustula, and Trigona spinipes) screening for seven of the most common pathogenic viruses (ABPV, IAPV, BQCV, CBPV, SBV, KBV, and DWV) in A. mellifera in summer and winter seasons. All seven stingless bee species studied were positive for ABPV and IAPV (only in M. quadrifasciata anthidioides and T. spinipes), while ABPV was found in samples from summer and winter, IAPV was only found in winter. This is the first study detecting viruses in seven native stingless bee species in Brazil and because of the novelty of this area in Brazil, it is necessary to monitor native stingless bee colonies to investigate the impact of those viruses at a colony and individual level to avoid losses and impact to the native bees.

Floral biology and flower visitors of cocoa (Theobroma cacao L.) in the upper Magdalena Valley, Colombia

Cocoa (Theobroma cacao L.) is an important crop, but yield is generally low. Improving yield requires detailed understanding of the reproductive ecology, especially the pollination system and factors determining pollination success, such as proximity to natural areas. Since the 1940s biting midges have been proposed as the pollinators of cocoa flowers but this idea has recently been questioned in various studies. We observed cocoa flowers and their visitors during anthesis, we compare cocoa flower visitors during the day and night and also in plantations connected and disconnected to natural forests. Observations of flowers during anthesis revealed that cocoa flowers are protandrous, open at night, persist for three days and are receptive only during the day. A diversity of insects visited flowers throughout 24 h. In general, insect visitors were more diverse during the day and in plantations connected to forests compared to those not connected to forests. Fifty five percent of the total insect species visited the cocoa flowers at night, all insect species visited cocoa flowers in plantations connected to natural forests and 62.5 % of those visited cocoa flowers in plantations disconnected with forests. Hymenoptera and Diptera were the main visitors and a total of eleven insect species carried cocoa pollen grains. Among those, two species of biting midges (Ceratopogonidae flies) and two species of stingless bees (Meliponini bees) were the most common. While biting midges were the most common visitors, the stingless bee Tetragonisca angustula carried large cocoa pollen loads and interacted with both the male and female parts of the flower. Ants also visited cocoa flowers, mainly at night. The most common visitors of cocoa flowers in cocoa plantations in the upper Magdalena Valley in Colombia are diurnal biting midges and stingless bees, but also nocturnal ants, suggesting that the pollination system of cocoa flowers may be locally less specialized than previously thought. Future research should investigate the effectiveness of various insect groups as pollinators.

Route of exposure to veterinary products in bees: Unraveling pasture's impact on avermectin exposure and tolerance in stingless bees.

Deforestation rapidly increases in tropical regions, primarily driven by converting natural habitats into pastures for extensive cattle ranching. This landscape transformation, coupled with pesticide use, are key drivers of bee population decline. Here, we investigate the impact of pasture-dominated landscapes on colony performance, pesticide exposure, and insecticide sensitivity of the stingless bee Tetragonisca angustula. We monitored 16 colonies located in landscapes with varying proportions of pasture. We collected bee bread for pesticide and palynological analysis. We found a positive correlation between pollen diversity and colony growth, with no effect of the proportion of pasture in the landscape. In contrast, we detected prevalent and hazardous concentrations of the insecticide abamectin (9.6-1,856 µg/kg) in bee bread, which significantly increased with a higher proportion of pasture. Despite the abamectin exposure, the bee colonies displayed no adverse effects on their growth, indicating a potential tolerance response. Further investigations revealed that bees from sites with higher proportions of pasture showed significantly reduced mortality when exposed to a lethal concentration of abamectin (0.021 µg/µL) after 48 h. Since abamectin is scarcely used in the study area, we designed an experiment to track ivermectin, a closely related antiparasitic drug used in cattle. Our findings uncovered a new exposure route of bees to pesticides, wherein ivermectin excreted by cattle is absorbed and biotransformed into abamectin within flowering plants in the pastures. These results highlight that unexplained exposure routes of bees to pesticides remain to be described while also revealing that bees adapt to changing landscapes.

In Vitro Antimycotic Activity and Structural Damage against Canine Malassezia pachydermatis Strains Caused by Mexican Stingless Bee Propolis.

This work describes the antimycotic activity of propolis from the stingless bees Scaptotrigona mexicana and Tetragonisca angustula, collected from two Mexican regions (Veracruz and Chiapas, respectively), against three clinical isolates and the reference strain ATCC 14522 of Malassezia pachydermatis, the causative agent of canine otitis. The chemical components of the ethanolic extracts of propolis were determined by gas chromatography coupled with mass spectrometry (GC-MS), and sesquiterpenes were the predominant compounds. The antimycotic activity was evaluated by plate microdilution. The induced changes in the yeasts were evaluated by fluorescence microscopy and staining with calcofluor white and propidium iodide. The minimum inhibitory concentration (MIC) was 7.11 mg/mL, and the minimum fungicidal concentration was 21.33 mg/mL for both extracts. The EPPs of Scaptotrigona mexicana and Tetragonisca angustula caused substantial damage to yeast morphology, where the propidium iodide staining of the yeasts treated with both EEPs revealed the penetration of this marker, which indicates the destruction of the cell wall and plasma membrane of the fungi. This result suggests that these types of propolis could be used as alternative treatments for canine external otitis. To the best of our knowledge, this seems to be the first scientific report that has demonstrated structural damage in Malassezia pachydermatis by Mexican stingless bee propolis.

Taxonomic and Functional Diversity of Flower-Visiting Insects in Coffee Crops.

Despite the important role that flower-visiting insects play in agricultural production, none of the previous studies of coffee pollinators in Colombia have incorporated functional diversity into their analysis. Therefore, this study aimed to quantify the abundance, richness, and functional diversity of insects that visit flowers in coffee crops. Twenty-eight plots were selected among five sites in the north, center, and south of Colombia. In each plot, coffee flower insect visitors were collected and recorded on 90 trees at eight-minute intervals per tree, at three different times over three days. All sampling was carried out during two flowering events per year, over three years, resulting in a total of 1240 h of observations. Subsequently, the insects were taxonomically identified, and the number of individuals and species, as well as the diversity of the order q, were estimated. Functional diversity was also characterized in the bee community. The results: (a) 23,735 individuals belonging to 566 species were recorded; of them, 90 were bees, with the native species being the most abundant during 10:30 and 13:00 h; (b) bees formed five functional groups, with corbiculate and long-tongued non-corbiculate bees being the most abundant and occupying the largest regions of functional space; (c) potential pollinators in coffee crops are Apis mellifera, Nannotrigona gaboi, Tetragonisca angustula, Geotrigona cf. tellurica, and Partamona cf. peckolti. Coffee crops host a wide diversity of flower visitors, especially bees, which could be beneficial for productivity and contribute to the maintenance of plant species that accompany coffee cultivation.

Antioxidant and anti-Alzheimer's potential of Tetragonisca angustula (Jataí) stingless bee pollen

Alzheimer's disease (AD) is considered the leading cause of dementia in the elderly worldwide. It results in progressive memory loss and impairment of cognitive and motor skills, leading to a high degree of disability and dependence. The development of AD is associated with the accumulation of senile plaques in the brain, caused by the amyloidogenic pathway of the disease. Several genetic and biochemical events are linked to AD development, with oxidative stress being one of them. Due to the scarcity of drugs aimed at treating AD, antioxidant compounds are increasingly studied as therapeutic targets for the disease. In this study, we investigate the antioxidant and anti-Alzheimer potential of the Tetragonisca angustula (Jataí) pollen extract in a Drosophila melanogaster Alzheimer's model. For this purpose, we utilized a D. melanogaster AD-like model, which expresses genes related to the amyloidogenic pathway of Alzheimer's disease. We explored the floral origin of the collected pollen, conducted phytochemical prospecting, and evaluated its antioxidant capacity in vitro. In vivo experiments involved assessing the survival and climbing ability of the D. melanogaster AD-like model with various concentrations of the pollen extract. Our findings revealed that the pollen extract of Tetragonisca angustula exhibits a significant antioxidant response and high concentrations of important phytochemicals, such as flavonoids and polyphenols. Furthermore, it enhanced the survival rate of D. melanogaster, and across all concentrations tested, it improved the climbing ability of the flies after 15 days of treatment with methanolic pollen extract. Additionally, the pollen extract reduced the neurodegeneration index in histopathological analysis. Thus, our study demonstrates the potential of Tetragonisca angustula pollen as an important subject for further investigation, aiming to isolate molecules that could potentially serve as therapeutic targets for Alzheimer's disease.

Distribution pattern of arthropods and their ecological interactions on the leaf surfaces of Terminalia argentea saplings.

Terminalia argentea tree, native to Brazil, is widely used in landscaping, recovering degraded areas, its wood, coal production, and the bark or leaf extracts has medicinal use. Despite of its importance, the arthropod fauna associated to this plant and its interspecific relationships still needs further studies. The objectives of this study were to evaluate the arthropods, their ecological indices and the distribution in the leaf faces on T. argentea saplings. The numbers of phytophagous insects (e.g., Cephalocoema sp.), pollinators (e.g., Tetragonisca angustula), and natural enemies (e.g., Oxyopidae), and their ecological indices (e.g., species richness), were higher on the adaxial leaf faces on T. argentea saplings. Aggregated distribution of phytophagous insects (e.g., Aphis spiraecola), pollinators (e.g., Trigona spinipes), and natural enemies (e.g., Camponotus sp.) on T. argentea saplings was observed. Abundance, diversity, and species richness of natural enemies correlated, positively, with those of phytophagous and pollinators insects. Predators and tending ants followed their prey and sucking insects, respectively. Tending ants protected sucking insects against predators, and reduced chewing insects. The high number of Cephalocoema sp. on T. argentea saplings is a problem, because this insect can feed on leaves of this plant, but its preference for the adaxial leaf face favors its control. The aggregation behavior of arthropods on T. argentea saplings favors the control of potential pests of this plant. There seems to be competition between tending ants for space and food resources on T. argentea saplings.