Peruvian Amazon Research Articles

Diet choices determine mercury exposure risks for people living in gold mining regions of Peru

Artisanal and small-scale gold mining (ASGM) is the largest global anthropogenic mercury (Hg) source and is widespread in the Peruvian Amazon. Consuming Hg-laden foods exposes people to this potent neurotoxin. While numerous studies have examined fish Hg content near ASGM, Hg accumulation in other commonly consumed animal-and plant-based foods from terrestrial environments is often overlooked. In this study, we aim to address understudied dietary Hg exposures.To understand Hg exposure from food staples in the Peruvian Amazon, we measured total and methyl Hg in local crops, fish, chicken meat, chicken feathers, and eggs from ASGM-impacted and upstream (reference) communities. Diet surveys were used to estimate probable weekly Hg intake from each food. Fish and chicken stable carbon and nitrogen isotope signatures were analyzed to evaluate trophic magnification.Though few crops exceeded food safety recommendations, rice methyl Hg proportions were high (84%). Trophic level was an expected key predictor of fish Hg content. 81% (17 of 21) of local carnivorous fish exceeded WHO and EPA recommendations. Compared to upstream communities, mining-impacted communities demonstrated elevated total Hg in crops (1.55 (interquartile ranges (IQR): 0.60–3.03) μg kg−1 upstream versus 3.38 (IQR: 1.62–11.58) in mining areas), chicken meats (2.69 (IQR: BDL–9.96) μg kg−1 versus 19.68 (IQR: 6.33–48.1)), and feathers (91.20 (IQR: 39.19–216.13) μg kg−1 versus 329.99 (IQR: 173.22–464.99)). Chicken meats from mining areas exhibited over double the methyl Hg concentrations of those upstream. Methyl Hg fractions in chicken muscle tissue averaged 93%. Egg whites and livers exceeded Hg recommendations most frequently. Proximity to mining, but not trophic position, was a predictor of chicken Hg content.Our results demonstrate that terrestrial and aquatic foods can accumulate Hg from mining activity, introducing additional human Hg exposure routes. However, locally sourced carnivorous fish was the largest contributor to an estimated three-fold exceedance of the provisional tolerable weekly Hg intake.

Physiological characterization and bioactive compounds of promising accessions of cowpea (Vigna unguiculata L. Walp) in the Peruvian Amazon

Cowpea production in the Peruvian Amazon is increasing due to its ability to adapt to diverse environments, its contribution to soil conservation, and its versatility of uses. This crop is particularly valuable in human nutrition due to its high nutritional quality and nutraceutical properties of its bioactive compounds. The aim of the study was to evaluate the physiology of cowpea plants in accessions PER1005854, PER1005851, and PER12645, under the influence of rice husk mulch, screw tree litter, and oil palm fiber, as well as to determine the bioactive compounds present in the grains. This study aims to promote sustainable cowpea production, expose the nutritional aspects of the grains, and foster their consumption both locally and nationally. The experiment was conducted from November 2022 to March 2023, in Yurimaguas, Loreto, Peru. The application of organic mulches demonstrates a significantly positive impact on the growth of cowpea accessions during their vegetative phase. This effect is possibly attributed to increased water availability, as the mulch reduces soil evaporation. In particular, cowpea accessions PER12645 and PER1005851 exhibit desirable physiological characteristics for grain production, with short cycles of 71 days and higher yields of 1141 and 1125 kg/ha respectively. In contrast, accession PER1005854 is distinguished by its higher biomass production, reaching a value of 14497 kg/ha, a relevant trait for foliage production and its contribution to soil conservation. The bioactive compounds, such as proteins, lipids, and carbohydrates, present in the accessions PER1005854, PER1005851, and PER12645, are similar to those found in other legumes. However, the antioxidant activity of dark tegument cowpeas proved to be superior, particularly highlighted in accession PER12645 (black tegument) with 26.3 μmolTG/g, and in accession PER1005854 (dark red tegument) with 19.5 μmolTG/g. This characteristic is particularly important for consumption, as it is related to the ability to combat oxidative stress in the human body.

Efficacy of a psychoeducational program on soft skills to reduce disruptive behavior among students in the Peruvian Amazon

Introduction: disruptive behavior, characterized by actions that interrupt or hinder the development of educational activities, has been the subject of increasing attention and interest in the academic field due to its significant impact on the school environment and the teaching-learning process. In this context, effectively intervening in these cases is crucial to create a safe and conducive school environment for learning.Objective: to evaluate the effectiveness of a psychoeducational program on soft skills to reduce disruptive behavior in students in the Peruvian Amazon.Methods: quantitative study, experimental design, and pre-experimental type. The sample consisted of 243 students from the fifth cycle of regular basic education. A psychoeducational program based on social skills was developed, and to assess its effectiveness, a questionnaire was administered before and after the intervention, which had adequate psychometric properties.Results: statistically significant differences (p<0,05) were identified between the overall scores of the disruptive behavior variable before (71,79) and after (48,20) the implementation of the psychoeducational program. Likewise, significant differences were observed between the average scores of the dimensions of classroom climate, effective communication, and interpersonal relationships before and after the intervention (p<0,05).Conclusions: the application of a psychoeducational program is effective in reducing disruptive behavior in students in the Peruvian Amazon. Therefore, it is recommended that future educational initiatives consider implementing similar programs to foster an enriching school environment that promotes personal growth and positive interactions

Assessment the mental health of university students in the Peruvian Amazon: A cross-sectional study

Introduction: the mental health of university students is a growing concern worldwide, as these young individuals face a series of emotional and psychological challenges during their transition to university life. Academic pressure, social demands, and adaptation to a new environment can affect their mental well-being.Objective: to assess depression, anxiety, and stress in students from two universities providing educational services in the city of Puerto Maldonado, Peru.Methods: quantitative study, non-experimental design, analytical type. The sample consisted of 307 university students of both genders who were administered the Depression, Anxiety, and Stress Scale, an instrument with adequate psychometric properties.Results: 42,7 % of students showed symptoms of depression, 52,4 % experienced anxiety, and 28,7 % suffered from stress. High, direct, and significant correlations were also reported between depression and anxiety (rho= 0,757; p<0,05), depression and stress (rho= 0,726; p<0,05), and anxiety and stress (rho= 0,811; p<0,05). Additionally, a statistically significant association was found between anxiety and students' age, as well as between stress and gender (p<0,05).Conclusions: it was concluded that students from two universities providing educational services in the city of Puerto Maldonado, Peru, presented symptoms of depression, anxiety, and stress. Therefore, it is suggested that universities implement early detection programs and psychological support services to address students' mental health issues

Using Acoustic Tomography to Model Wood Deterioration in Cedrelinga cateniformis Ducke in the Peruvian Amazon

Forest plantations can be established in order to restore degraded areas. Acoustic tomography, which is of increasing importance in forest management, was used in the present study to obtain information for managing plantations of Cedrelinga cateniformis Ducke in the Peruvian Amazon. The species is valuable in the timber sector of Peru, but the core wood tends to deteriorate and develop cavities. The main objective of the study was to model wood deterioration in Cedrelinga cateniformis Ducke using the data obtained through acoustic tomography. Eight plantations of varying ages were analyzed using acoustic tomography in order to obtain indicators of wood deterioration. Biometric, climatic, and edaphic data (explanatory variables) were also measured in each plantation. The indicator variables and explanatory variables were compared and evaluated using correlation and principal component analysis. Wood deterioration was modelled using stepwise regression. The indicator variables differed significantly between plantations and were mainly correlated with the biometric variables (age and diameter at breast height). The models explained 81% of the variability of pith rot. The percentage rotten area was minimal in young plantations (1%), and the opposite was observed in mature trees (21.5 to 25.6%). The study findings provide valuable information, enabling foresters to determine the optimal age and diameter for felling Cedrelinga cateniformis in plantations in the Peruvian Amazon.

Toxoplasma gondii in a Remote Subsistence Hunting-Based Indigenous Community of the Peruvian Amazon.

Toxoplasma gondii is a ubiquitous zoonotic protozoan parasite that infects a wide variety range of warm-blooded animals. This study describes the epidemiological scenario of T. gondii in an indigenous community that relies on subsistence hunting in a well-conserved and isolated area of the Peruvian Amazon. The high seropositivity against T. gondii in humans (83.3% IgG and 6.1% IgM), wild mammals (30.45%, 17 species), peri-domestic rodents (10.0% Rattus sp.), and domestic animals (94.1% dogs and 100% cats) indicates the existence of a sylvatic cycle in the community under study. Individual age was found to be positively associated with IgG detection against T. gondii but not with IgM. It is estimated that each family consumed 5.67 infected animals per year with terrestrial species having higher infective rates than arboreal species. The main risk factors included improper handling and cooking of wild meat, poor hygiene practices, and feeding uncooked offal to domestic animals. This scenario results in a continuous process of infection and reinfection within the indigenous community with cats, dogs, and peri-domestic animals becoming infected through the ingestion of infected raw viscera. Our results emphasize the need to promote safe food handling practices and disposal of waste materials from hunted animals in such communities.

Scouts vs. usurpers: alternative foraging strategies facilitate coexistence between neotropical Cathartid vultures

Understanding how diverse assemblages of scavengers can coexist on shared ecological resources is a fundamental challenge in community ecology. However, current approaches typically focus on behaviour at carcass provisioning sites, missing how important differences in movement behaviour and foraging strategies can facilitate sympatric species coexistence. Such information is particularly important for vultures – obligate scavengers representing the most endangered avian foraging guild. Their loss from ecosystems can trigger trophic cascades, mesopredator release and disease outbreaks. We provide the first‐ever analyses of GPS location data from wild King Vultures Sarcoramphus papa and Greater Yellow‐headed Vultures Cathartes melambrotus, coupled with trait data (from both wild‐living and museum specimens) and visitation data from camera traps deployed at provisioned carcasses, to characterize vulture flight behaviour and strategies in the Peruvian Amazon. We found marked species differences in several key movement characteristics, including: King Vultures having home‐ranges five times larger, average flight heights four times greater and ground speeds 40% faster than those of Greater Yellow‐headed Vultures. Despite these differences, both species flew similar distances each day (on average), probably due to King Vultures taking 50% fewer flights and spending 40% less time in the air per day. Consistent with these patterns, King Vulture body mass was more than double that of the Greater Yellow‐headed Vulture, with a substantially larger hang wing index (a measure of long‐distance flight efficiency). At carcasses, Greater Yellow‐headed Vultures typically arrived first but were rapidly outnumbered by both King and Black Vultures Coragyps atratus. We find that the movement behaviour of obligate apex scavengers in the western Amazon is linked to their ability to coexist – Greater Yellow‐headed Vultures, a smaller stature ‘scouting’ species adapted to fly low, forage early and arrive first at carcasses, are ultimately displaced by larger‐bodied, wider ranging King Vultures at large ephemeral carrion resources. Expansion of future GPS tracking initiatives could facilitate the exploration of direct facultative interactions from animal movement data and give further insight into how diverse communities assemble and interact.

Two new dactylogyrid species (Dactylogyroidea: Dactylogyridae), gill parasites of freshwater fishes from the Peruvian Amazon, including the proposal of Peruanella n. gen.

A new genus of dactylogyrid, Peruanella n. gen., is proposed to accommodate Peruanella madredediosensis n. sp. from Brachyplatystoma tigrinum (Britski) (Siluriformes: Pimelodidae) from the Madre de Dios River, in Puerto Maldonado City, Madre de Dios region, Peru. The new genus differs from Neotropical dactylogyrids by possessing a combination of the following features: (1) tandem gonads, (2) a tubular J-shaped MCO, (3) an accessory piece connected to the base of the MCO via a filament, (4) a midventral vaginal aperture, (5) anchors similar in shape, each with short roots, (6) straight and robust bars, and (7) equal hook, each with undilated shanks and a depressed thumb. A previously described species, Demidospermus aureagarciae Morey, Rojas, Dávila, Chu & De Pina, 2023 exhibits characteristics that are compatible with the diagnosis of the new genus; therefore, this species is transferred to the Peruanella n. gen. In addition, Jainus peruensis n. sp. is described from Brycon amazonicus (Spix & Agassiz) (Characiformes: Bryconidae). This new species, which is the first species of the genus described in Peru and the third species infecting a bryconid host, can be differentiated from all congeneric species due to: (1) a slender MCO forming a counterclockwise loop at the proximal end, (2) an unarticulated accessory piece with a scythe-shaped distal end, (3) a rod-shaped ventral bar with a medial projection, and (4) a V-shaped and grooved dorsal bar.

Determinación de parámetros tecnológicos en curtición vegetal de piel de paiche (Arapaima gigas) con extracto de quebracho (Schinopsis balansae) y mimosa (Acacia dealbata) para el aprovechamiento industrial ambientalmente sostenible

La crianza de paiche en la Amazonía peruana produce suficiente materia prima para la elaboración de cuero a base de piel de pescado; sin embargo, estas pieles representan un problema de contaminación debido a su limitado aprovechamiento. En esta investigación, se resalta la relevancia de emplear procedimientos tanto mecánicos como químicos con el fin de obtener cuero de excelente calidad. Para llevar a cabo este proceso, se utilizaron diferentes concentraciones de quebracho y mimosa. El cuero de piel de paiche resultante fue resistente y moldeable, con una capacidad de resistencia a la flexión que excede las 30 000 flexiones sin deformación, mayor resistencia al desgarro en T1 (146.23 N) y T5 (143.12 N) y mayor tracción en T4 (16.62 N/mm2). Además, presentó un contenido de cenizas inferior al 1%, humedad inferior al 9% y óxido de cromo inferior al 1.5%. Se trataron además los efluentes generados durante el proceso, los cuales presentaron valores aceptables de pH, conductividad y DQO.

Changes in floristic and vegetation structure in a chronosequence of abandoned gold-mining lands in a tropical Amazon forest

This study analyzes floristic and vegetation structure changes during forest succession after disturbances caused by small-scale gold mining in Madre de Dios (Peru). We compared the floristic and vegetation structure of a reference forest against three sites with different periods of abandonment after mining (5, 11 and 23-years). Three 20 × 60 m plots were defined on each site, and all tree species with a DBH >1 cm within the plots were inventoried. To evaluate species diversity and similarity, the Importance Value, effective numbers of species (0D, 1D, and 2D), and Chao-Jaccard similarity index were calculated. We used the Nonmetric multidimensional scaling for similarity ordination and the PERMANOVA test to evaluate differences in floristic composition. We recorded 129 tree species in the study areas and statistically significant differences between initial and intermediate stages were observed regarding floristic composition, basal area, height, and DBH. The transition from the initial successional stage to the reference forest produces an increase in basal area, species diversity, and floristic similarity. The 23-year-old stand had more species in common with the 11-year-old stand than the reference forest. Our results showed a high proportion of pioneer species and anemochory dispersal syndrome in the initial successional stages, but they decreased in later stages of the chronosequence. The floristic and structural attributes of forests throughout the chronosequence showed a fast recovery during secondary succession. After 23 years, the recovery of tree species density was 77 % of reference forest, while the relative recovery of species composition was much slower, on average 23 %. These results provide essential information to guide the selection of suitable species in ecological restoration projects after abandonment. Implementing forest restoration strategies based on reliable information to accelerate the process of vegetation succession is critical for recuperating areas degraded by gold mining at the Peruvian Amazon.

Effect of spatiotemporal variables on abundance, biting activity and parity of Nyssorhynchus darlingi (Diptera: Culicidae) in peri-Iquitos, Peru

BackgroundIn malaria endemic regions of the Peruvian Amazon, rainfall together with river level and breeding site availability drive fluctuating vector mosquito abundance and human malaria cases, leading to temporal heterogeneity. The main variables influencing spatial transmission include location of communities, mosquito behaviour, land use/land cover, and human ecology/behaviour. The main objective was to evaluate seasonal and microgeographic biting behaviour of the malaria vector Nyssorhynchus (or Anopheles) darlingi in Amazonian Peru and to investigate effects of seasonality on malaria transmission.MethodsWe captured mosquitoes from 18:00 to 06:00 h using Human Landing Catch in two riverine (Lupuna, Santa Emilia) and two highway (El Triunfo, Nuevo Horizonte) communities indoors and outdoors from 8 houses per community, during the dry and rainy seasons from February 2016 to January 2017. We then estimated parity rate, daily survival and age of a portion of each collection of Ny. darlingi. All collected specimens of Ny. darlingi were tested for the presence of Plasmodium vivax or Plasmodium falciparum sporozoites using real-time PCR targeting the small subunit of the 18S rRNA.ResultsAbundance of Ny. darlingi varied across village, season, and biting behaviour (indoor vs outdoor), and was highly significant between rainy and dry seasons (p < 0.0001). Biting patterns differed, although not significantly, and persisted regardless of season, with peaks in highway communities at ~ 20:00 h in contrast to biting throughout the night (i.e., 18:00–06:00) in riverine communities. Of 3721 Ny. darlingi tested for Plasmodium, 23 (0.62%) were infected. We detected Plasmodium-infected Ny. darlingi in both community types and most (20/23) were captured outdoors during the rainy season; 17/23 before midnight. Seventeen Ny. darlingi were infected with P. vivax, and 6 with P. falciparum. No infected Ny. darlingi were captured during the dry season. Significantly higher rates of parity were detected in Ny. darlingi during the rainy season (average 64.69%) versus the dry season (average 36.91%) and by community, Lupuna, a riverine village, had the highest proportion of parous to nulliparous females during the rainy season.ConclusionsThese data add a seasonal dimension to malaria transmission in peri-Iquitos, providing more evidence that, at least locally, the greatest risk of malaria transmission is outdoors during the rainy season mainly before midnight, irrespective of whether the community was located adjacent to the highway or along the river.

Resilience of Aboveground Biomass of Secondary Forests Following the Abandonment of Gold Mining Activity in the Southeastern Peruvian Amazon

Amazon rainforests are critical for providing a wide range of ecosystem services. In the Southeastern Peruvian Amazon; however, goldmining activities are causing severe soil degradation and forest loss. We analyzed aboveground biomass (AGB), forest structure, and species diversity recovery during secondary succession in 179 forest plots. Our study provides the first field-based quantification of AGB recovery following the abandonment by two types of goldmining (heavy machinery and suction pumping) in Madre de Dios (Peru). We found that successional secondary forests in areas subjected to suction pumping were more resilient than those in areas subjected to heavy machinery. After 20 years, mean AGB in suction pumping mining areas had reached 56% of reference forest AGB, while in areas of heavy machinery mining it was only 18%. Mining type, stand age, and distance from the forest edge had a significant effect on AGB. The influence of the distance from the forest edge on AGB varies according to mining type because the effects of species diversity on AGB are mediated by the distance from the forest edge. Our results clearly showed the dynamics of AGB recovery across a secondary succession after goldmining, and the contrasting responses of AGB between the two mining types. Our study disentangles the importance of key factors in forest recovery after mining and improves understanding of the resilience of biomass accumulation in these highly degraded ecosystems.

Helicobacter pylori exposure among the Awajún of the Peruvian Amazon: Prevalence and environmental, social, and biological associations.

Helicobacter pylori (H. pylori)-a gastric bacteria affecting almost 50% of the global population and leading to ulcers and cancer in severe cases-is a growing health concern among Indigenous populations who report a high burden of reported poor general health and gastrointestinal distress. We test hypothesized associations between H. pylori exposure patterns and environmental, social, and biological conditions among a sample of 212 Indigenous Awajún adults (112 males, 100 females, ages 18-65 years) living in the northern Peruvian Amazon. Dried blood spots were analyzed for H. pylori-specific IgG using a recently developed enzyme-linked immunosorbent assay. Resulting seropositivity rates and antibody concentrations, proxying past exposures to H. pylori were analyzed in relation to relevant environmental (toilet type, floor material, reported water quality), social (household size and education level), and biological (age, sex, BMI, blood pressure, immune and metabolic biomarkers) factors using multivariable regression analyses. We found near ubiquitous seropositivity for H. pylori exposure in our sample (99.1% seropositive). In the regression analyses, elevations in H. pylori antibody concentrations were significantly higher among males compared to females (β = 0.36, p = 0.01). No associations were found with any other factors. Anthropological research in the study communities suggests that the male bias in elevations of H. pylori antibody concentrations is related to cultural and biological factors. Future research is needed to further unravel these biocultural dynamics and determine whether elevations in H. pylori antibody concentrations have clinical relevance for gastrointestinal health outcomes in this population.

Research competencies assessment: Case of university students in the Peruvian Amazon

In the university context, research competences acquire a transcendental role for the integral development of students and the advancement of knowledge in all academic disciplines. Therefore, the objective of the present research was to evaluate the research competences of students of the Peruvian Amazon universities who attend the ninth and tenth semester. The investigation was developed under a quantitative approach; the design was non-experimental and the type was cross-sectional descriptive. The sample was made up of 135 students to whom the Research Competences Questionnaire was administered, an instrument with an adequate level of validity and reliability. According to the results, the level of development of the research competences of 43.7% of students were low, of 37% was medium, while 19.3% was high. Likewise, the organizational competences, communicational competences and collaborative competences dimensions were also valued at a low level. On the other hand, it was found that the level of research competencies was significantly associated with the semester of study in which the students were (p&lt;0.05). It was concluded that the level of development of the research competences that characterized students was low. Therefore, it is recommended that the competent university authorities promote a culture of research in the academic environment and provide specific research training programs.

Implementation of new technologies designed to improve cervical cancer screening and completion of care in low-resource settings: a case study from the Proyecto Precancer

BackgroundThis case study details the experience of the Proyecto Precancer in applying the Integrative Systems Praxis for Implementation Research (INSPIRE) methodology to guide the co-development, planning, implementation, adoption, and sustainment of new technologies and screening practices in a cervical cancer screening and management (CCSM) program in the Peruvian Amazon. We briefly describe the theoretical grounding of the INSPIRE framework, the phases of the INSPIRE process, the activities within each phase, and the RE-AIM outcomes used to evaluate program outcomes.MethodsProyecto Precancer iteratively engaged over 90 stakeholders in the Micro Red Iquitos Sur (MRIS) health network in the Amazonian region of Loreto, Perú, through the INSPIRE phases. INSPIRE is an integrative research methodology grounded in systems thinking, participatory action research, and implementation science frameworks such as the Consolidated Framework for Implementation Research. An interrupted time-series design with a mixed-methods RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) evaluation framework was used to examine the adoption of human papillomavirus (HPV) testing (including self-sampling), with direct treatment after visual inspection with portable thermal ablation, at the primary level.ResultsThis approach, blending participatory action research, implementation science, and systems-thinking, led to rapid adoption and successful implementation of the new cervical cancer screening and management program within 6 months, using an HPV-based screen-and-treat strategy across 17 health facilities in one of the largest public health networks of the Peruvian Amazon. Monitoring and evaluation data revealed that, within 6 months, the MRIS had surpassed their monthly screening goals, tripling their original screening rate, with approximately 70% of HPV-positive women reaching a completion of care endpoint, compared with around 30% prior to the new CCSM strategy.ConclusionsProyecto Precancer facilitated the adoption and sustainment of HPV testing with subsequent treatment of HPV-positive women (after visual inspection) using portable thermal ablation at the primary level. This was accompanied by the de-implementation of existing visual inspection-based screening strategies and colposcopy for routine precancer triage at the hospital level. This case study highlights how implementation science approaches were used to guide the sustained adoption of a new screen-and-treat strategy in the Peruvian Amazon, while facilitating de-implementation of older screening practices.

Caza y comercio de carne de origen silvestre: Estudio de caso en tres comunidades nativas amazónicas de Ucayali, Perú

Poco se sabe cómo operan los mercados de carne de monte en la Amazonía peruana y la influencia que tienen sobre los niveles de extracción con fines alimenticios y comerciales. La investigación analiza cómo el precio de la carne de monte se relaciona con la intensidad de caza en comunidades nativas cercanas a la ciudad de Pucallpa. El estudio confirma que la extracción, comercio y uso de carne de monte en estas comunidades están relacionados con la comercialización del recurso en la ciudad. La cantidad de carne compartida, carne vendida y el precio promedio influyen sobre la cantidad total de carne cazada. Si los precios varían, las cantidades de carne cazada para la venta varían también. Se recomienda promover la autorregulación local, mediante la cual las propias comunidades se organizan asegurando la permanencia de poblaciones saludables de fauna silvestre y beneficiarse sin perjudicar el ecosistema. Se sugiere promover la venta legal de carne de monte de especies manejadas en los mercados formales de Pucallpa para que el comercio pueda estar sujeto a mayor control y permitir que los precios logren un nivel de equilibrio sostenible en la extracción y venta de carne de monte.

The downstream effects of COVID-19 on adolescent girls in the Peruvian Amazon: qualitative findings on how the pandemic affected education and reproductive health

Due to COVID-19, schools were closed to mitigate disease spread. Past studies have shown that disruptions in education have unintended consequences for adolescents, including increasing their risk of school dropout,...

EXTRACTO ANTIOXIDANTE ENCAPSULADO POR ATOMIZACIÓN Y POR INCLUSIÓN MOLECULAR A PARTIR DE CÁSCARA Y SEMILLA DE CAMU CAMU (Myrciaria dubia)

Camu camu (Myrciaria dubia) is a fruit from the Peruvian Amazon, highly valued for its high content of vitamin C, which is concentrated in its pulp. Due to this nutritional characteristic, it is processed into juices and extracts. However, its industrialization generates a considerable amount of waste. Therefore, its utilization is vital to reduce environmental pollution. The content of phenolic compounds in the peel and seed of camu camu has been studied, indicating that factors such as drying temperature and the method of stabilizing the concentrated powder are key to preserving its antioxidant activity. The objective of the study was to evaluate two drying temperatures (50 and 65°C) on camu camu seeds and peels, analyzing their effect on the total phenol content and the efficacy of atomization encapsulation and molecular inclusion of the concentrated extract at the optimal temperature. Extraction was conducted out with food-grade ethanol solvent at a ratio of 1:40 (g/g), at 55°C for 30 minutes, then concentrated to 60% in a rotary evaporator. At 50°C, a lower of phenolics (4979.99 ± 94.24 mg gallic acid equivalent (GAE)/100g of sample) was found in the peel and seed mixture, and total anthocyanins in the peel (47.82 ± 3.93 mg cyanidin/100 g sample).. Atomization and molecular inclusion of the concentrated extract showed efficacy in in retaining the encapsulated total phenols. In conclusion, using a temperature of 50°C for drying has a lesser impact on the content of polyphenols. Additionally, two alternatives for stabilizing the extract are presented: with maltodextrin and molecular inclusion with cyclodextrin, both equally effectives.

Soil carbon stock potential in pastoral and silvopastoral systems in the Peruvian Amazon

AbstractResearch evaluating the impact of silvopastoral systems on physical and biological properties of Amazonian soils is scarce. Thus, this study aimed to compare the soil carbon storage potential and physical and chemical soil properties of silvopastoral systems (SPS) and conventional pastoral systems (CPS) in the San Martin region of Peru. Using the Walkley and Black method, we analyzed soil organic matter at two different depths (0–15 cm and 15–30 cm). In addition, bulk density, soil moisture, total porosity, and mechanical resistance were measured in both systems. The highest (P &lt; 0.05) carbon stocks were reported at 0–15 cm of depth with values of 31.4 Mg ha−1 and 34.4 Mg ha−1 for CPS and SPS, respectively. At 15–30 cm depth, the total carbon stock was higher for SPS, with 29.12 Mg ha−1, than for CPS, which had 26.4 Mg ha−1. Despite the absence of statistically significant differences, soil carbon stocks were higher in SPS. No significant differences in soil moisture were found between systems, although soil moisture was slightly greater in SPS than CPS (28 and 25%, respectively). The CPS had 59% of the total porosity, which was higher than the SPS. Mechanical resistance was lower in SPS (2.15 kg/cm2) than in CPS (2.33 kg/cm2) at 10 cm of depth. These results indicated that the SPS has the potential to store more carbon and improve physical and chemical traits in the soil than the CPS.

Slow environmental justice: the Cuninico oil spill and the legal struggle against oil pollution in Peruvian Amazonia

ABSTRACT This paper analyzes a case of environmental activism after one of the largest oil spills in Peruvian Amazonia, the 2014 Cuninico oil spill. A relatively more independent judiciary, environmental legislation, and weak though autonomous regulatory agencies led to a shift in institutional opportunity structure over the previous 20 years. The embryonic environmental state produced evidence of environmental harm and sanctioned state-owned oil enterprise Petroperú. However, that was not enough to produce timely measures to protect the affected communities. Indigenous peoples affected by the spill worked with human rights lawyers and civil society coalitions to bring the company to court. Almost a decade of high court activism has meant a burdensome process of ‘lawfare’ with important legal triumphs for plaintiffs. In 2020, a historic ruling mandated financial compensation for affected communities. Despite these triumphs, the long wait for the restitution of justice hints at an uncertain future.