As the production of metal-based nanomaterials increases, it is inevitable that nano-scale products and byproducts will enter the aquatic environment. In terms of global production, the most abundant nano-oxides are TiO2, CeO2 and Fe3O4 nanoparticles. Chironomus riparius is commonly used for ecotoxicological assessment and defining its histopathological biomarkers that showcase the toxic effect of tested nanoparticles should lead to a better understanding of the consequences of nanomaterial accumulation in aquatic ecosystems. In this study, a histological description of the digestive and excretory systems as well as the fat body structure of C. riparius larvae is provided. In addition, potential histological biomarkers of nano-oxide toxicity were determined based on the obtained histopathological alterations in organs. Vacuolization was observed in epithelial cells of midgut region I that were treated with nano-Fe3O4 as well as in Malpighian tubules treated with nano-Fe3O4 and nano-CeO2. Larvae exposed to nano-TiO2 showed alterations in the fat body and midgut region II tissue architecture. Additionally, shortening of the intestinal brush border was determined in groups exposed to nano-Fe3O4. These results reveal the high sensitivity of these organs, which can be used as biomarkers in histopathological assessment and therefore lead to further improvement of existing methodology in ecotoxicological studies.

In this paper the content, DPPH radical scavenging capacity and the chelating activity on Fe2+ of free and bound phenolics extract from wheat and porcino flours were determined. The content of phenolic compounds in the extracts of free and bound phenolics from the wheat flour was 4.49 and 196.79 μg/g, and in the porcino flour these contents were 860.02 and 30.38 μg/g, respectively. The content of total phenolics in the porcino flour was considerably higher than that in the wheat flour. For DPPH test, the IC50 the value of free and bound phenolics from the wheat flour was 2.48 and 0.23 mg/ml, respectively, and these values for phenolics from the porcino flour were 0.22 and 0.06 mg/ml, respectively. For reducing power, the IC50 value of free and bound phenolics from the wheat flour was 5.12 and 0.21 mg/ml, and from the porcino flour it was 0.87 and 0.28 mg/ml, respectively. Free and bound phenolics from the porcino flour have a better DPPH scavenging capacity, and free phenolics from the porcino flour have a better reducing power than phenolics from the wheat flour. The results show that the addition of porcino to wheat flour could improve the antioxidant potential of the wheat flour and of final food products which could be obtained from the wheat-porcino flour mixture.

The holometabolous insects go through a complete metamorphosis that includes four life stages: egg, larva, pupa, and imago (adult). Chironomus riparius is a suggested model organism by the Organization for Economic Cooperation and Development (OECD) that is used in acute and chronic tests of chemicals. Tissue morphology of healthy non-biting midge larval stage was already described but the faith of the midgut digestive cells and tissue organization during the metamorphosis is unknown. We here described histological alterations of the midgut during ecdysis to distinguish them from the ones caused by toxins’ negative effects. The present study showed differences in tissue architecture of the midgut in the larval, prepupal, and pupal stages of development of C. riparius. During ecdysis, larval digestive cells detached from the midgut epithelium and moved to the lumen. In the pupa, the larval midgut layer was replaced with an adult midgut that had considerably reduced width. These changes in the midgut tissue morphology and organization probably follow changes in the environment and feeding behavior of C. riparius at different stages of development.

Recurrent landscape fires may threaten biodiversity in small protected areas embedded within human-dominated landscapes. We assessed fire occurrence and its spatial coincidence with species of conservation concern in protected natural area “Lalinačka Slatina”, by integrating stakeholder surveys, NASA FIRMS active-fire records, hydrometeorological data, and field-based mapping of selected plant and bird features. Stakeholders identified 48 fire-associated locations in the past decade, over 93% of which were linked to agricultural land or waste-disposal sites. The FIRMS dataset contained 1,073 active-fire detections, while 80% of MODIS detections recorded during 2001–2025 occurred between July and October. Maximum monthly temperature was positively associated with fire activity (IRR = 1.071, p = 0.0015), whereas precipitation had a negative effect (IRR = 0.957, p < 0.001). Direct correspondence between stakeholder-derived polygons and FIRMS detections was limited, indicating that the two sources captured complementary aspects of local fire occurrence. Fire exposure of selected species was spatially heterogeneous, reaching 98.8% in one mapped bird area and 100%, 96.5%, and 66.6% in several plant subpopulations. These results identify specific conservation-important areas where recurrent fire exposure is concentrated and provide a basis for targeted prevention, surveillance, and future ecological monitoring.

Mideopsis roztoczensis Biesiadka & Kowalik, 1979 (Acari, Hydrachnidia, Mideopsidae) is a common and often abundant component of macroinvertebrate communities in Palearctic streams. Although the external morphology and genetic structure of this species are relatively well documented, knowledge of its internal anatomy remains limited, despite its importance for an integrative understanding of morphology and evolutionary diversity. The present study utilized histological techniques to investigate and describe the internal structures of M. roztoczensis based on newly collected material from Serbia. Histological analyses revealed the organization of several internal organs, including an extensive blind sac-like excretory organ that was morphologically distinct from the midgut, while a hindgut was not identified. Additionally, other structures, including dermal glands, the midgut, salivary glands, and the synganglion, were characterized. The observed variation in internal organization, particularly the morphology of the excretory organ and the number of paired dermal glands, provides additional characteristics in comparative morphological studies of water mite. This study contributes to our current knowledge of the internal anatomy of Hydrachnidia and highlights the value of histological approaches for future integrative studies of water mites.