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Algae are natural products with great potential as aquafeed ingredients, being rich in nutrients and bioactive compounds. They can improve fish health while being sustainable at social, economic, and environmental levels, contributing to the one health concept. In this study, two micro- (Nannochloropsis oceanica and Chlorella vulgaris) and two macroalgae (Gracilaria gracilis and Ulva rigida), produced under commercial conditions, were selected to unravel their nutritional value (protein and lipid content; fatty acid and amino acid profiles), as well as antimicrobial activity against farmed fish and shrimp pathogenic bacteria and bioactive potential by assessing ABTS+• and DPPH• scavenging capacities. A commercial blend of these algae (ALGAESSENCE™—Feed) was included to determine possible synergistic effects. Nannochloropsis oceanica was rich in eicosapentaenoic acid and arachidonic acid (ARA) and G. gracilis had high content of ARA. Chlorella vulgaris had the highest levels of essential amino acids (EAAs), namely lysine. The blend is a well-balanced and rich source of proteins, lipids, essential fatty acids, EAAs and carbohydrates. The single algae and the blend displayed bactericidal and bacteriostatic activities against most of the tested pathogenic bacteria, with the most promising results being observed against Tenacibaculum maritimum (40–45% activity). In some cases, the micro- and macroalgae had no simultaneous bactericidal and bacteriostatic activities, but the blend was able to both kill and inhibit the growth of those bacteria. The algae had also some antioxidant activity, with G. gracilis and the blend presenting the highest values. The present results showcased the blend as a promising ingredient to be included in aquafeeds.

Fruits and vegetables (FV) consumed in natura or processed produce a significant volume of waste, causing an economic deficit in the productive chain. FV markets feature a significant production of vegetable residues with potential of use, since they commercialize an increasing amount of minimally processed vegetables and fruit juices. To this end, it is important to identify, quantify, and characterize these wastes and to propose feasible and coherent alternatives for their use at regional and worldwide levels. In this paper, a case study of two FV markets in Rio de Janeiro, Brazil, was conducted to identify and quantify FV processing waste. Over a period of 20 days, the FV residues from 31 vegetables and 17 fruits were identified and weighed. It is estimated by extrapolation that 106,000 kg of FV were processed in 1 year in two units of FV markets and 48.6% of FV were discarded as by-products. This may be a consequence of factors that contribute to waste generation, such as the low preparation and/or training of the manipulators as well as the quality of the equipment and the maintenance thereof. Thus, studies that aim to understand the environmental impact by monitoring the of FV waste are fundamental, since this waste can be used as raw material and converted into value-added products.

Gibberellic acid elicited synthesis of many phenols from different classes and enhanced production of sesquiterpenoids, polyterpenoids, steroids and monoterpenoids compared to control and 6-benzylaminopurine. Little is known about the effects of 6-benzylaminopurine (BA) and gibberellic acid (GA3) on the synthesis of secondary metabolites in species of Lamiaceae. In this study, for the first time, the profile of secondary metabolites in plantlets of Cunila menthoides was characterized, using UPLC-ESI-Qq-oaTOF-MS. Ninety metabolites were identified, including polyphenols and terpenes. BA down-regulated most of the identified molecules in relation to GA3 and MS0 (control). The results showed that GA3 elicited synthesis of many phenols from different classes, and seemed to play a major role in the shikimate pathway in relation to BA. GA3 enhanced production of sesquiterpenoids, polyterpenoids, steroids and monoterpenoids compared to MS0 and BA, and also seemed to positively influence the MEP/DOXP and MVA pathways. These data show the most comprehensive metabolomic profile of Cunila menthoides to date, and the effects of BA and GA3 on the synthesis of secondary metabolites, modulating quantitative aspects of metabolism in Lamiaceae.

An increasing effort is dedicated to investigate the potential of native plants used in traditional medicine as a source of bioactive compounds for numerous industries. The bioprospection of the metabolome of medicinal and/or endangered plants has two important merits: confirming or revealing the biotechnological potential of that species, and assisting in its conservation. In addition, biotechnological techniques, such as tissue culture, are key strategies in conservation and multiplication of medicinal plants. This is the first in vitro development and non-targeted metabolome study by UPLC–QTOF–MSE of extracts from C. menthoides, an endangered medicinal plant. In vitro development investigation with a wide range of plant growth regulators resulted in maximum survival rate (81%) and the highest growth rate (1.74 cm ± 0.36) for plantlets cultured on Murashige and Skoog medium, supplemented with 1 µM gibberellic acid. Maximum rooting occurred on medium supplemented with 4.4 µM 6-benzyladenine, which also resulted in more leaves per plantlet (10.16 ± 1.7). We developed a protocol that can be used for the clonal propagation and ex situ conservation of this species. In terms of metabolome analysis, a total of 107 metabolites from several classes were detected and identified in its hydrophilic extract (HE), including organic acids and derivatives, glucosinolates, terpenes, phenolic compounds as well as other polar metabolites. The metabolites in HE with the greatest signal intensity included the isoquinoline alkaloid magnoflorine; the coumaric acid rosmarinic acid; the steroid-cardanolide convallatoxin; two anthraquinones including the poorly investigated ventinone A. Several molecules identified here carry potential pharmacological benefits such as anti-inflammatory and anticancer applications.

The conditions that a population experiences during one season can affect the strength of density dependence in the following season. In the tropics, many populations face their biggest challenges in the dry season due to limited food and cold-dry conditions. Seasonal environmental changes can be especially problematic for small, short-lived, seasonally breeding endotherms. To investigate the effects of seasonality on population dynamics, we studied five marsupial species in the Brazilian Atlantic Forest, using a 16-year dataset. We tested if (1) compensatory density feedback is stronger in the dry season, due to the high population sizes and limited food; (2) lower temperatures and the overall abundance of small mammals negatively affect dry season population growth rates; and (3) rainfall, a proxy for food availability, is positively related to wet season population growth rates. Population growth rates were regressed against seasonal population sizes and exogenous variables, and analyzed with linear autoregressive models. Seasonal compensatory density feedback occurred in both seasons, with compensation processes in just one season being sufficient to allow population persistence. Rainfall and the overall abundance of small mammals had little influence on populations, while colder temperatures decreased population growth rate of smaller species in both seasons. Although the study marsupials share similar life histories and phylogeny, they varied with respect to the season when compensatory density feedback was strongest. Our results demonstrate that seasonality plays a key role in driving marsupial population dynamics, and highlight the need to account for seasonality in demographic studies even in tropical environments.

The relative effect of survival and reproductive rates to population growth rate is expected to be similar across species with similar life-histories. We employed a matrix population model and sensitivity and elasticity analysis to assess the absolute and relative importance of age-specific survival and fertility to population growth rate of Didelphis aurita (Didelphimorphia, Didelphidae) in a rural area of Rio de Janeiro, southeastern Brazil. The results were compared to expectations for mammals that mature early and have short generation time, such as D. aurita. Prospective analysis showed that changes in pouch young and juveniles survival would have large effects on population growth rate, relative to other vital rates, being the most critical time periods in the life cycle of D. aurita, whereas the effect of fertilities were always low. These findings do not fit to the observed pattern in mammals that mature early, where reproductive parameters have the largest relative influence on population growth rate. Although reproductive rates were characterized by a relatively small influence on population growth rate, they are still relevant because of their high variability and response to potential environmental disturbances. The first application of matrix population models to a neotropical rainforest marsupial provides information on marsupial demography and life-history strategy, increasing comprehension of this unknown group.