Wild populations of the pustulose ark, Anadara tuberculosa (Bivalvia), an emblematic species of the East Pacific mangrove ecosystem declined in South American countries (Colombia, Ecuador, and Peru) mainly due to overharvesting and habitat loss or degradation. Understanding the genetic aspects of geographic variations and population structure of A. tuberculosa, currently unknown, appears as a priority to fishery authorities in order to elaborate integrated and collaborative conservation policies for fishery management, aquaculture, and stock enhancement programs. We used mtDNA sequence data to investigate haplotype diversity, genetic structure, and demography of A. tuberculosa. Results indicate genetic homogeneity of populations distributed north and south of the equator, respectively. However, statistically significant differentiation emerged between northern and southern populations with pairwise ф_ST values ranging between 0.036 and 0.092. The oceanic current system acting in the area (Panama Current and Humboldt Current) might play a role in limiting the larval dispersal of the species, still poorly understood. Demography reconstruction supported recent population expansion, possibly started after last glacial maximum. Our results would suggest separate and independent management of populations north and south of the equator.

The pustulose ark A. tuberculosa is an emblematic species of mangrove ecosystem that is currently in a vulnerable condition. The development of its aquaculture, to begin with genetic breeding programs, requires the identification of molecular biomarkers, particularly those associated with salinity stress. With this purpose, specimens of A. tuberculosa were collected from the adjacent mangroves of Puerto Pizarro bay (Tumbes, Perú), from January 2015 to February 2016. Different assays (groups of ten animals in triplicate) were undertaken in separated periods of 16 days: hypo-osmotic stress (extreme: 5, 10 ppt); (Moderate: 15, 25 ppt) and no stress (control group: 33 ppt). The presence of salinity stress biomarkers was assessed at the genetic level throughout PCR detection of 19 genes reported to be key actors in osmoregulation, and at the proteomic level with the sequencing of peptides (tandem mass spectrometry MALDI TOF/TOF), expressed in ark tissues exposed to different salinities. None of the tested genetic markers could be amplified by PCR, suggesting that A. tuberculosa has significant genetic differences compared to other mollusks. Proteomic analysis by mass spectrometry on A. tuberculosa gill tissue, allowed to identify 26 peptides expressed in presential and differential forms at different salinities, highlighting possible markers such as HSP70 and trans-membrane chloride channel transportation protein, to be related with salinity adaptation. These amino acid sequences will allow the design of target specific primers for A. tuberculosa, to implement future research in ecophysiology of this important fishery resource.

Sustainable starch-based bioplastics have emerged as promising alternatives to conventional plastics for fresh produce packaging, yet their efficacy in preserving highly perishable fruits remains underexplored. Strawberries cv. San Andreas, prone to rapid postharvest deterioration, require packaging that balances moisture retention and gas exchange to maintain quality. This study developed lucuma seed starch-based bioplastics incorporated with free (EO) or microencapsulated (EOM) lemon verbena essential oil and evaluated their performance during 16 days of refrigerated storage (4 °C) compared to non-active bioplastic (Control) and commercial low-density polyethylene (LDPE). Microencapsulation enhanced the stability and controlled release of bioactive compounds. The EOM treatment reduced weight loss to 12.81% (vs. 18.25% in Control and 6.29% in LDPE), while preserving firmness at 3.87 N (vs. 2.19 N in LDPE). Strawberries packaged in both EO and EOM exhibited complete suppression of visible decay (0% incidence) throughout storage, in stark contrast to LDPE (57.34% incidence). The EOM system also maintained higher levels of total phenolics (205.51 mg GAE/100 g FW), antioxidant capacity (289.05 µmol TE/100 g FW), and anthocyanins compared to LDPE and Control treatments. These findings demonstrate that lucuma seed starch bioplastics containing microencapsulated lemon verbena essential oil represent a sustainable and functional packaging strategy to extend shelf life and preserve the quality of highly perishable strawberries during refrigerated storage.

Background: Essential oils (EOs) are promising natural antimicrobials against food-borne pathogens, yet their efficacy depends on complex chemical profiles that vary by species and origin. The evaluation of underexplored aromatic plants from the Peruvian Amazon may reveal novel bioactive agents. Methods: We chemically characterized six EOs from Aloysia citrodora, Arracacia xanthorrhiza (two cultivars), Baccharis genistelloides, Piper acutifolium, and Piper lanceifolium using GC-MS and assessed their antibacterial activity against Escherichia coli (ATCC 25922), Salmonella enterica (ATCC 14028), Enterococcus faecalis (ATCC 29212), and Staphylococcus aureus (ATCC 49476). Results: EOs of Aloysia citrodora and Arracacia xanthorrhiza cv. Yellow exhibited the strongest inhibition, effective against both Gram-positive and Gram-negative bacteria, potentially associated with higher relative abundances of oxygenated monoterpenes and aliphatic aldehydes. Dose–response analysis supported their superior antibacterial potency, with the lowest LD₅₀ values observed for these oils. Oils rich in sesquiterpenes showed lower activity. Conclusions: These findings underscore the importance of EO chemical composition for antibacterial potency and suggest that select Amazonian EOs have potential as natural preservatives for food safety applications.

Cyanide leaching is currently the dominant process used by the mineral industry to extract gold and silver minerals. Cyanide is a nitrogen compound toxic for most living organisms. Many microorganisms are able to tolerate and degrade cyanide and its derivatives. In this study, were considered bacteria from soil and water samples corresponding to a chronological sequence (up to 5 years) of spontaneous cyanide bioremediation in a gold mining area (La Libertad Region, Peru). Culture dependent molecular identifications, based on 16S rDNA amplification and sequencing, were performed for bacteria isolated on agar media. Co-culture dependent molecular identifications were performed through 16S rDNA targeted metagenomics based on Next generation Sequencing with DNA directly extracted from the co-cultures in order to determine bacteria species unable to grow individually on agar media. Culture independent identifications were similarly performed through 16S rDNA targeted metagenomics from DNA directly extracted from water or soil samples in order to establish their respective global microbiota. Concerning cyanide contaminated soils, more than one hundred operational taxonomic units (OTU) were identified by metagenomics with only 30% species co-cultivable in broth medium and 82 isolated strains, in particular Pseudomonas spp. The global microbiota in non-contaminated soils was markedly different. Concerning cyanide contaminated waters, about one hundred operational taxonomic units (OTU) were identified by metagenomics with only 30% species co-cultivable in broth medium. The most frequently identified species belong to Alcaligenes, Alkalibacterium, Bacillus, Paenibacillus and Serratia. Bacteria isolated and co-cultivated from contaminated waters and soils are currently analyzed as candidates for cyanide bioremediation.

Neltuma pallida is a multi-purpose tree species of the seasonally dry tropical forests of northern Peru, where it provides essential ecological and socioeconomic functions. However, recurrent defoliation associated with the cecidomyiid gall midge Enallodiplosis discordis may compromise early seedling establishment and the success of forest restoration programs. This study evaluated the effects of larval infestation on foliar integrity and established quantitative damage thresholds in N. pallida seedlings under dry forest conditions. Insects collected from naturally infested plants were identified using an integrative taxonomic approach that combined classical morphological diagnosis with COI-based DNA barcoding obtained by Sanger sequencing. Morphological assessment assigned the defoliating dipteran to E. discordis, while BLASTn v2.17.0. analysis of the 576-bp partial COI sequence showed 92.6% identity and 100% query coverage with Cecidomyiidae records, supporting its taxonomic placement within this family. Field bioassays conducted over a 17-week period, in which 25 individual seedlings were evaluated (N = 25), revealed a strong and significant positive correlation between larval density and foliar damage percentage (r = 0.872; p < 0.001), with moderate damage levels predominating throughout the evaluation period. Despite sustained larval presence, seedlings did not reach severe damage categories, suggesting potential relative tolerance to partial defoliation under the evaluated field conditions. Temperature and relative humidity were not significantly associated with infestation intensity or foliar damage during the study period. Overall, these findings indicate that E. discordis-associated foliar damage represents a relevant, although not necessarily lethal, biotic constraint for the early regeneration of N. pallida under the field conditions assessed. The quantitative thresholds reported here provide useful criteria for dry forest restoration programs, phytosanitary monitoring, and integrated pest management strategies in the Peruvian dry forest.