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Novel foods especially formulated and targeted for the elderly population should provide sufficient nutrients and bioactive ingredients to counteract the natural age-related deterioration of various organs and tissues. Dietary protein and phenolic compounds achieve this goal; however, older adults have alterations in their gastrointestinal system that may impact their bioavailability and few studies have been aimed at this population. Since phenolic compounds are the subject of multiple biotransformations by host and microbiome enzymes during the digestion process, identification of their bioavailable forms in human plasma or tissues represents a considerable analytical challenge. In this study, UHPLC-ESI-QTOF/MS-MS, chemometrics, and multivariate statistical methods were used to identify the amino acids and phenolic compounds that were increased in the plasma of elderly adults after a 30-day intervention in which they had consumed an especially formulated muffin and beverage containing Brosimum alicastrum Sw. seed flour. A large interindividual variation was observed regarding the amino acids and phenolic metabolites identified in the plasma samples, before and after the intervention. Three phenolic metabolites were significantly increased in the population after the intervention: protocatechuic acid, 5-(methoxy-4'-hydroxyphenyl) valerolactone, and phloretic acid. These metabolites, as well as others that were not significantly increased (although they did increase in several individuals), are probably the product of the microbiota metabolism of the major phenolic compounds present in the B. alicastrum Sw. seed flour and other food ingredients. A significant decrease in 4-ethyl-phenol, a biomarker of stress, was observed in the samples. Results showed that the incorporation of foods rich in phenolic compounds into the regular diet of older adults contributes to the increase in bioactive compounds in plasma, that could substantially benefit their mental, cardiovascular, and digestive health.

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An experiment was carried out to assess the effect of the incorporation of sun-dried foliage of Brosimum alicastrum into rations based on hay of Megathyrsus maximus on intake, rumen fermentation, kinetics of passage, microbial nitrogen supply to the small intestine, apparent digestibility in Pelibuey hair sheep. Four rations were randomly allotted to four rumen-cannulated lambs (BW = 37.4 ± 4.9 kg) using a 4 × 4 Latin square design to assess the effect of increasing levels (0, 15, 30 and 45% DM basis) of foliage of Brosimum alicastrum on a basal ration of M. maximus. Organic matter intake and water consumption increased linearly (p < 0.01) with increasing levels of B. alicastrum in the ration. The rate and potential extent of rumen fermentation of OM and CP of B. alicastrum were 10.6%/h and 86.6% and 11.4%/h and 95.2%, respectively, but no effect (p > 0.05) was found on the potential rumen degradation of DM (40.2%) or on the rate of degradation of DM (0.033%/h) of M. maximus, although a positive effect was found in the rumen degradation rate of NDF (p < 0.05). VFA and ammonia concentration in the rumen and the rate of passage of solids and liquids through the rumen (k1) increased linearly (p < 0.01) with increasing levels of B. alicastrum. Rumen pH was not affected by the incorporation of B. alicastrum (p > 0.05). Microbial nitrogen supply to the small intestine (p < 0.001), apparent digestibility of dry matter (p < 0.01) and NDF (p < 0.05) of the rations were also significantly increased as a result of the incorporation of B. alicastrum foliage. Results from this experiment suggest that the foliage of Brosimum alicastrum can be readily incorporated at around 30% of the ration of dry matter in hair sheep with beneficial effects on feed intake, rate of passage and microbial N supply to the lower tract.

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ETHNOPHARMACOLOGICAL RELEVANCE: Brosimum alicastrum is a tree used in Mexican traditional medicine for the treatment of several diseases, including uterine cancer. AIM OF THE STUDY: In this study, the cytotoxic activity of aqueous extract of B. alicastrum bark and isolated compounds xanthyletin (1), luvangetin (2), and 8-hydroxyxanthyletin (3) on three human cancer cell lines was determined. Moreover, the biological effects of 8-hydroxyxanthyletin (3) were investigated. MATERIALS AND METHODS: The aqueous extract was prepared according to the ethnomedical information reported from the bark. The compounds were purified using chromatographic methods and their structures were elucidated by spectroscopic techniques. The antiproliferative effect of aqueous extract and isolates was determined in three human tumor cell lines: HeLa, A2780, and MSTO-211H, and evaluated by trypan blue exclusion assay. The cell cycle and the mitochondrial transmembrane potential (ΔΨ) were measured by flow cytometry, while Reactive Oxygen Species (ROS) levels were determined using 2',7'-dichlorofluorescein diacetate (DCFH-DA) probe. The effect on the relaxation activity, mediated by topoisomerase I and II, was evaluated by electrophoresis, and docking studies were performed using Autodock 4.2 to analyze the interactions. RESULTS: Aqueous extract of B. alicastrum bark showed significant antiproliferative effect on the evaluated cancer cell lines (IC50 = 1.6, 8.5, and 21.4 µg/ml). Four coumarins were identified in the extract and three of them were also evaluated. A2780 cell line exhibited higher sensitivity against pyranocoumarins with IC50 values ranging from 32 to 47 µmol/l. 8-hydroxyxanthyletin (3) exerts an interesting effect on human topoisomerases I and II, by inhibiting the enzymes at concentrations comparable to those obtained in antiproliferative assay. Moreover, 8-hydroxyxanthyletin (3) arrests the cell cycle at G0/G1 phase and induces in A2780 cells a concentration-dependent increase in ROS levels. The results of molecular docking suggest the participation of the hydroxyl group in the interaction between 8-hydroxyxanthyletin (3) and topoisomerase I and II. CONCLUSION: This is the first report that demonstrates the cytotoxic activity of the aqueous extract of B. alicastrum bark, and determines the main metabolites.

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PREMISE: The mechanisms generating the geographical distributions of genetic diversity are a central theme in evolutionary biology. The amount of genetic diversity and its distribution are controlled by several factors, including dispersal abilities, physical barriers, and environmental and climatic changes. We investigated the patterns of genetic diversity and differentiation among populations of the widespread species Brosimum alicastrum in Mexico. METHODS: Using nuclear DNA microsatellite data, we tested whether the genetic structure of B. alicastrum was associated with the roles of the Trans-Mexican Volcanic Belt and the Isthmus of Tehuantepec as geographical barriers to gene flow and to infer the role of past events in the genetic diversity patterns. We further used a maximum-likelihood population-effects mixed model (MLPE) to identify the main factor affecting population differentiation in B. alicastrum. RESULTS: Our results suggested that Mexican B. alicastrum is well differentiated into three main lineages. Patterns of the genetic structure at a finer scale did not fully correspond to the current geographical barriers to gene flow. According to the MLPE mixed model, isolation by distance is the best model for explaining the genetic differentiation of B. alicastrum in Mexico. CONCLUSIONS: We propose that the differentiation patterns might reflect (1) an ancient differentiation that occurred in Central and South America, (2) the effects of past climatic changes, and (3) the functions of some physical barriers to gene flow. This study provides insights into the possible mechanisms underlying the geographic genetic variation of B. alicastrum along a moisture gradient in tropical lowland forests.

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Physiological changes in elderly individuals (EI) can contribute to nutritional deterioration and comorbidities that reduce their quality of life. Factors such as diet can modulate some of these effects. The aim was to evaluate the functionality of foods added with Brosimum alicastrum Sw. seed flour in EI. EI (n = 23) living in nursing home conditions agreed to participate. A control stage was carried out (30 days) and subsequently, an intervention stage (30 days) was realized in which a muffin and a beverage, designed for EI, were added to the participants' their usual diet. In both stages, anthropometric parameters, body composition, nutritional status, dietary intake, sarcopenic status, cognitive and affective states, biometric parameters, and total phenolic compounds (TPC), and antioxidant capacity in foods and plasma of EI were determined. The results showed that the consumption of the foods improved the energy intake and preserved the muscle reserves of the EI. The EI gained body weight (+1.1 kg), increased their protein (+18.6 g/day; 1.5 g/kg BW/day), dietary fiber (+13.4 g/day), iron (+4.4 mg/day), zinc (+1.8 mg/day), folic acid (+83.4 µg/day) consumption while reducing their cholesterol (-66 mg/day) and sodium (-319.5 mg/day) consumption. LDL-C lipoproteins reduced (14.8%) and urea (33.1%) and BUN (33.3%) increased. The TPC increased (7.8%) in the plasma, particularly in women (10.7%). The foods improve the EI nutritional status, and this has a cardiovascular protective effect that can benefit the health of the EI.

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RESUMEN Se midieron los flujos de materia orgánica aportados por la hojarasca al manantial de Cañaverales (La Guajira, Colombia), durante un período de seis meses (seco y lluvioso). La caída mensual fue de 0,17 t-ha-1mes-1, que extrapolada a un año representó 2,08 t-ha-1-año-1, valor intermedio a los registrados en otros bosques secos tropicales. Se evidenció una correlación significativa entre la caída de hojarasca y la precipitación. Los aportes orgánicos fueron dominados por la fracción foliar (66,61 %), seguidos del material reproductivo (15,92 %), el material leñoso (11,12 %) y misceláneo (6,36 %). La mayor caída de hojarasca foliar se registró para Prosopisjuliflora (1,31 t-ha-1-año1) y la menor caída la presentó Brosimum alicastrum (0,46 t-ha^-año1). Las especies P. juliflora y Anacardium excelsum presentaron los mayores aportes de hojarasca foliar, lo que sugiere que podrían ser especies potenciales para su inclusión en actividades de restauración de zonas con corrientes de agua. P. juliflora fue la especie que presentó mayores tasas de descomposición de hojarasca (0,242 año-1), mientras que la Sterculia apetala fue la más persistente (0,079 año1). Los resultados indican que la caída de hojarasca está condicionada por la composición del bosque y las variaciones climáticas.

ABSTRACT We analyzed the contribution of particulate organic matter to the spring Cañaverales (La Guajira, Colombia) over a period of six months (dry and rainy). The monthly litterfall was 0.17 t-ha-1-month-1, which represented 2.08 t-ha-1-year-1 when extrapolated to one year. This is an intermediate value with respect to others reported from tropical dry forests. The correlation between litter production and precipitation was statistically significant. Litterfall was dominated by the leaf fraction (66.61 %), followed by the reproductive material (15.92 %), the woody (11.12 %) and miscellaneous materials (6.36 %). The highest production of leaf litter was registered for Prosopis juliflora (1.31 t-ha-1 year1) and the lowest for Brosimum alicastrum (0.46 t-ha^year1). P. juliflora and Anacardium excelsum, presented the major contributions of foliar leaf litter, what suggests they could be potential species for inclusion in restoration activities in riparian areas. P. juliflora was the species that presented the highest rates of litter decomposition (0.242 year1), while the Sterculia apetala was the most persistent (0.079 year-1). The results indicate that litterfall and litter decomposition rates depend on forest composition and climatic variations.

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In order to maximize the yield of the total phenolic content (TPC) and total monomeric anthocyanin (TMA) from Brosimum alicastrum leaf and to study the radical-scavenging activity, a three-level three-factor Box-Behnken design (BBD) was used to determine the optimal points for ultrasound-assisted extraction (UAE). In this study, we analyzed the extraction time (10, 20, and 30 min), temperature (28, 30, and 32 °C), and probe sonication power (40%, 28 W/cm²; 60%, 51 W/cm²; and 80%, 74 W/cm²). Analysis of variance (ANOVA) indicated that the sonication power plays a significant role in the extraction of phenolic compounds. An increase in time and temperature resulted in a decrease in the yield, in particular, of the TMA group. DPPH was found to be a better indicator of radical-scavenging activity than ABTS. The predicted TPC and TMA optimum levels (45.18 mg GAE/g and 15.16 mg CyE/100 g) were obtained at 28 °C, 80%, and 20-10 min. DPPH obtained a maximum value (67.27 µmol TE/g) under same optimization conditions. The RSM confirmed that TPC and TMA enhanced the antioxidant activity when subjected to low temperature (28 °C), extraction time less than 20 min, and higher sonication power (74 W/cm²), and hence achieving the better DPPH scavenging activity.

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In this paper, the Ramon starch was isolated and its chemical composition and physical and microscopic characteristics were determined. Corn starch was used as reference. In general, the proximal composition was similar between starches studied. Ramon starch granules were oval-spherical and rounded with sizes between 6.5 and 15 µm. Starch purity was high (92.57%) with amylose content of 25.36%. The gelatinization temperature was 83.05°C and transition enthalpy was 21.423 J/g. At 90°C, solubility was 20.42%, swelling power 17.64 g water/gstarch and water absorption capacity was 13 gwater/gstarch. The pH, clarity and color (Hue angle) of Ramon starch were higher to those reported for corn starch. The results achieved suggest that Ramon starch has potential for application in food systems requiring high processing temperatures and it is also a promising option for use in the manufacture of biodegradable materials.

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Growth, survival and herbivory of seedlings in Brosimum alicastrum (Moraceae), a species from the Neotropical undergrowth. Growth responses, survival, and herbivory, on seedlings of Brosimum alicastrum were studied in a neotropical Mexican forest. We selected 122 seedlings and divided them into three groups assigned to defoliation treatments: control or 0 (n=21), 50 (n=51) and 90% (n=50). Every 4 months during two years we measured seedling growth (in terms of relative growth rate in biomass, leaf area growth, produced leaves and height growth) and survival. In addition, we evaluated every 12 months pathogen damage and insect herbivory using a 2 mm-2 grid. Separately, we estimated mammal herbivory in 3-month old seedlings that were selected within a plot of 500 m x 10 m (N=1095). Pathogen damage and insect herbivory were evaluated within the same plot in 113 seedlings. We found that 50 % defoliated seedlings showed compensatory responses in all growth parameters. Relative growth rate and height growth also had a compensatory response in seedlings at 90% defoliation. Relative growth rate and leaf area growth gradually decreased with time although height growth seedling showed an opposite pattern. Leaves produced were not affected by time. Estimated seedling survival probability increased with defoliation to a maximum of 97%, decreasing at 24 month to 37%. Mammal herbivory was more frequent and severe than herbivory caused by pathogens and insects. In some cases, mammal herbivory produced total defoliation. Compensatory growth in leaf area growth, produced leaves and height growth seedling suggest a synergic compensatory mechanism expressed in a whole-plant growth biomass (relative growth rate). Compensation and survival results suggest trade-offs at the leaf level, such as leaf area growth and produced leaves versus chemical defenses, respectively. Rev. Biol. Trop. 56 (4): 2055-2067. Epub 2008 December 12.

Se estudiaron las respuestas de crecimiento, supervivencia y los diferentes tipos de herbivoría sobre plántulas de B. alicastrum en una selva neotropical de México. Se seleccionaron 122 plántulas de una población las cuales se asignaron a tres tratamientos de defoliación: control o 0% (n=21), 50% (n=51) y 90% (n=50). Cada 4 meses durante dos años se midió su crecimiento (en términos de la tasa relativa de crecimiento en biomasa, área foliar, hojas producidas y altura) y supervivencia. Además cada 12 meses, mediante el uso de una cuadricula de 2mm-2, se evaluó la herbivoría causada por patógenos e insectos. También dentro de una parcela de 500 m largo x 10 m de ancho se evaluó en 1095 plántulas de 3 meses de edad la herbivoría por mamíferos. En la misma parcela pero en 113 plántulas se estimó la herbivoría por patógenos e insectos. Las plántulas defoliadas al 50% compensaron su crecimiento en todas las estructuras medidas, pero sólo la tasa relativa de crecimiento y altura lo hicieron con la defoliación al 90%. La tasa relativa de crecimiento y el área foliar disminuyeron gradualmente con el tiempo, contrario a la altura con un patrón opuesto. El número de hojas producidas no se afectó por el tiempo. La probabilidad estimada de supervivencia incrementó hasta un 95% con la defoliación y disminuyó hasta un 37% a los 24 meses. La herbivoría por mamíferos fue el más incidente y severo, en algunos casos hasta un 100% de defoliación. En tanto la causada por patógenos e insectos fue secundaria. El crecimiento compensatorio en área foliar, producción de hojas y altura sugieren un mecanismo compensatorio sinérgico expresado a nivel del crecimiento individual de la planta (tasa de crecimiento en biomasa). Al mismo tiempo junto con la supervivencia sugiere un posible compromiso entre las respuestas de crecimiento a nivel de la hoja - área foliar y hojas producidas - versus producción de defensas químicas.

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Scarabaeinae are sensitive to structural habitat changes caused by disturbance. We compared copronecrophagous beetle (Scarabaeinae) community structure in three differently managed zones within an agroeco-system of the northern Yucatan Peninsula, Mexico. We placed dung and carrion traps once a month from June 2004 through May 2005. The beetle community included 17 species from the genera Canthon, Canthidium, Deltochilum, Pseudocanthon, Malagoniella, Onthophagus, Phanaeus, Copris, Uroxys, Sisyphus and Ateuchus. The secondary vegetation had a higher beetle diversity than the other two zones. Species richness was highest in the Brosimum alicastrum plantation. The pasture had the lowest species diversity and richness, but exhibited the highest abundance of Scarabaeinae in the dry season. The two zones with extensive tree cover were the most diverse. Roller beetles were dominant over burrower species and small-sized species outnumbered large species. Our data show two important issues: beetle species in the pasture extended their activity to the beginning of the dry season, while abundances dropped in the other, unirrigated zones; and the possibility that the Scarabaeinae living in neotropical forests are opportunistic saprophages and have specialized habits for resources other than dung. The B. alicastrum plantation is beneficial to the entire ranch production system because it functions as a dispersion and development area for stenotopic species limited to tree cover.

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To test the premises and predictions of the Janzen-Connell model (Janzen's spacing mechanism), seeds of the rainforest canopy tree, Brosimum alicastrum, were placed at different distances from the parent tree and their removal observed over 3 weeks. The number and density of naturally occurring seeds at different distances from the parent tree were also estimated. Predation was not greater near the parent tree, except on the very small spatial scale: the proportion of experimental seeds removed was greater 1 m from the trunk than it was 5-25 m from the trunk. Predation was negatively correlated with seed density, not positively as the Janzen-Connell model assumes-presumably due to predator satiation. The density of seeds after predation peaked 5 m from the tree trunk, but this is well within the crown radius of the parent tree. There is a peak in the number of potential recruits at a distance of 10 m from the parent tree, due to the peaked initial distribution of seeds. This peak is caused by the interaction between the seed density curve and the increasing area of an annulus around the parent tree at increasing distances, not by the product of the density curve and the predation curve. However, it is important to realize that it is not the presence of a peak in recruitment away from the parent that is essential to maintaining tropical tree species diversity, but frequency-dependent recruitment induced by poor recruitment near conspecifics. Predator satiation seems to be an important factor in the survival of B. alicastrum seeds, possibly at several spatial scales. The number of seeds produced by the tree is negatively correlated with the loss to predators, and trees that have a fruiting conspecific nearby also suffer lower levels of predation. Seed predation increases as one moves from the forest edge into the interior, creating an edge effect that may have long-term effects on the forest composition and tree species diversity. More studies are needed, for other species, other localities, and larger spatial and temporal scales, on both the Janzen-Connell mechanism and this edge effect.