Hydrogel properties of non-conventional starches from guabiju, pinhão, and uvaia seeds.

The physicochemical properties of starch vary depending on the botanical sources, thereby influencing the gelatinisation/retrogradation properties and subsequently affecting the hydrogels characteristics. This study aimed to assess the influence of botanical sources influence on starch and hydrogel properties using non-conventional starch derived from guabiju, pinhão, and uvaia seeds. Hydrogels were prepared by starch gelatinisation followed by 6 h ageing period at room temperature (20 ± 2 °C) and subjected to five freeze-thaw cycles. Pinhão starch exhibited a higher viscosity peak and breakdown, along with a lower final viscosity and setback, compared to guabiju and uvaia starches. The significantly different pasting properties influenced the porous microstructure, water absorption (p-value: 0.01), and resistance of the hydrogels (p-value: 0.01). The guabiju starch hydrogels showed a uniform pore structure without cavities, whereas pinhão and uvaia starch hydrogels exhibited agglomerated and spongy pore structures. Furthermore, the guabiju starch hydrogel demonstrated the lowest water absorption (4.56 g/g) and the highest compression resistance (1448.50 g) among all the studied starch hydrogels. In contrast, the pinhão starch hydrogel showed the highest water absorption (7.43 g/; p-value: 0.01) among all studied starch hydrogels. The hardness of uvaia starch hydrogel did not differ significantly from the guabiju and pinhão starch hydrogel. The different non-conventional starches reveal important variations in the hydrogels characteristics. This provides insights into how amylose and amylopectin interact and present alternatives for using these unique starch-based hydrogels in diverse applications.

Quality Attributes and Metabolic Profiles of Uvaia (Eugenia pyriformis), a Native Brazilian Atlantic Forest Fruit.

The uvaia is a native Brazilian Atlantic Forest Myrtaceae fruit with a soft pulp, ranging from yellow to orange, with a sweet acidic flavor and sweet fruity aroma. Uvaias present consumption potential, but their physicochemical characteristics are still understudied. In this context, we describe herein the metabolites of uvaia that have been determined by nuclear magnetic resonance spectroscopy. We screened 41 accessions and selected 10 accessions based on their diversity of physicochemical attributes, i.e., their fresh mass, height, diameter, yield, seed mass, total soluble solids, and titratable acidity. Twenty-six metabolites were identified, including sugars, acids, and amino acids. The results of this study comprise the most complete report on sugars and acids in uvaias. The relevant metabolites in terms of abundance were the reducing sugars glucose and fructose, as well as malic and citric acids. Furthermore, this study represents the first description of the uvaia amino acid profile and an outline of its metabolic pathways. Uvaia quality attributes differ among accessions, demonstrating high variability, diversity, and several possibilities in different economic areas. Our findings may help in future breeding programs in the selection of plant material for industries such as food and pharmaceuticals.

Bioactive Compounds and In Vitro Antioxidant Capacity of Cambuci and Uvaia: An Extensive Description of Little-Known Fruits from the Myrtaceae Family with High Consumption Potential.

Cambuci (Campomanesia phaea O. Berg Landrum) and uvaia (Eugenia pyriformis Cambess), both native Atlantic Rainforest fruits, are noteworthy for being rich in bioactive compounds and their significant antioxidant capacity. Despite the numerous known edible fruits in the world, consumption by humans is most often restricted to a few dozen of them. Such behavior occurs, among other reasons, due to the lack of knowledge about fruits not yet commercialized on a large scale. This study quantified the bioactive compound content (total phenolic compounds and ascorbic acid in cambucis and uvaias; proanthocyanidins in cambucis, and total carotenoid profile and individual carotenoids for grapes) and antioxidant capacity of the edible parts (peel and pulp) of cambuci and uvaia accessions, using three methods (ABTS•+, ROO• radical scavenging and HOCl elimination). Cambuci contained higher phenolic compound levels and displayed higher antioxidant capacity determined by the ABTS•+ and ROO• radical scavenging methods than uvaia (139 and 119 mg 100 g-1 of GAE, 10.5 and 7.73 µmol g-1 of TE; 9.17 and 5.92 µmol g-1 of TE, respectively). Vitamin C content and the antioxidant capacity determined by the HOCl elimination method were about 1.5- and 6-fold higher in uvaia compared to cambuci, with the latter being a first-time report for uvaia. Both fruits contained higher levels of bioactive compounds and antioxidant capacity than other commonly consumed fruits.

In vitro antiglycation and antioxidant properties of Eugenia pyriformis leaves and fruits.

Eight phenolic compounds were isolated from Eugenia pyriformis leaves fraction by semi-preparative HPLC and characterized by Nuclear Magnetic Resonance (NMR) and mass spectrometry (ESI-MS). Five compounds were isolated and identified for the first time in E. pyriformis species, while this is the first report of the accumulation of isoquercitrin, quercitrin, and the aglycone quercetin in its leaves. E. pyriformis leaves and fruits extracts, as well as the compounds isolated from the leaves most active fraction, were evaluated for their antiglycation and antioxidant activities. The mixture of myricetin-3-O-(2″-O-galloyl)-α-L-rhamnoside and myricetin-3-O-(4″-O-galloyl)-α-L-rhamnoside showed the highest antiglycation activity. These results suggest that this species is a promising source of bioactive compounds. Further studies to investigate the inhibition of the glycation process in vivo are necessary to evaluate its use in the treatment and/or prevention of advanced glycation end-products (AGEs)-associated diseases.

Chemical Composition and In Vitro Antimicrobial Activity of the Essential Oil Obtained from Eugenia pyriformis Cambess. (Myrtaceae)

Abstract Our study aimed to evaluate the chemical composition of the essential oil from the leaves of Eugenia pyriformis Cambess., belonging to the Myrtaceae family and native to the Brazilian Atlantic forest. The volatile compounds in the essential oil were extracted by hydrodistillation and analyzed using GC-MS; 36 compounds accounted for 78.80% of the total oil content. The major compounds were β-caryophyllene, bicyclogermacrene, globulol, and (δ-cadinene. We evaluated their antimicrobial potential of the essential oil and toxicity to Artemia salina. The antimicrobial activity of the essential oil was evaluated against 12 microorganisms using the broth microdilution method. Our results showed moderate inhibition of Staphylococcus aureus and methicillin-resistant S. aureus (MIC, 250 and 125 μg.mL-1, respectively) and toxicity to A. salina (LC50, 125.64 μg.mL-1). Our results establish the biological activity of the essential oil obtained from E. pyriformis.

A critical review of some fruit trees from the Myrtaceae family as promising sources for food applications with functional claims.

The Myrtaceae family is one of the world's leading commercial fruit tree families. Among the 121 genera belonging to this family, the Syzygium, Eugenia and Campomanesia genera are constituted by a wide variety of fruit species with great potential to be explored economically, besides presenting excellent nutritional value and being considered sources of phytochemicals such as phenolic compounds, carotenoids and volatile compounds. Many of these phytochemicals have been linked to the prevention and management of several chronic and degenerative diseases including cancer, cardiovascular diseases, type 2 diabetes mellitus, obesity, amnesia among other disorders. In this context, this review discusses about the importance of four fruits species representative of Myrtaceae family such as Syzygium cumini, Syzygium malaccense, Eugenia pyriformis and Campomanesia xanthocarpa, focusing on the nutrients and phytochemical constituents as well as demonstrating their biological effects in order to stimulate the cultivation and consumption of these fruits.

Biocidal potential of Eugenia pyriformis essential oil in the control of Rhipicephalus (Boophilus) microplus in the free-living cycle / Potencial biocida do óleo essencial de Eugenia pyriformis Cambess no controle de Rhipicephalus (Boophilus) microplus no ciclo de vida livre

Brazil has one of the largest commercial cattle herds in the world, which naturally coexist with an enormous number of parasitic species. Southern cattle tick, Rhipicephalus (Boophilus) microplus, is among these species, interfering with animal productivity and causing losses to the beef and dairy cattle sector. The use of chemical acaricides in the control of this mite has resulted in the emergence of resistant populations. In this sense, alternative control measures using plants as sources of botanical acaricides have shown to be effective. Eugenia pyriformis Cambess is a Brazilian plant with antioxidant and antimicrobial activity; however, there are no reports on its acaricidal activity in the literature. The present study aimed to evaluate the acaricidal and larvicidal potential of E. pyriformis leaf essential oil (EO) on southern cattle tick at different stages of the reproductive cycle. E. pyriformis leaves were collected and dried, and had their EO extracted by hydrodistillation (3h) using a modified Clevenger apparatus. Chemical analysis was performed by gas chromatography coupled with mass spectrometry (GC/MS), and 32 compounds belonging to the sesquiterpene class were identified: hydrocarbons (17.98%) and oxygenated forms (81.96%), with spathulenol (43.65%) and caryophyllene oxide (12.17%) as the most common. The EO was evaluated by the Adult Immersion Test at the concentrations (500.00 to 3.12mg/mL) in which the following parameters were measured: mortality of females (%), hatchability of eggs (%), and product efficiency (%). Larvae were assessed by the Larval Packet Test at concentrations ranging from 25.00 to 0.00004mg/mL. Lethal concentrations (LC) required for killing 50 and 99.9% of adult females and larvae were determined using Probit analysis. LC50 and LC99.9 of EO were 0.06 and 24.60mg/mL and 1,208.80 and 2,538mg/mL for larvae and adult females, respectively. Action of the EO in the free-living cycle of R. (B.) microplus larvae was another parameter assessed. To this end, the larvae were deposited in pots containing Brachiaria decumbens and, after migration to the leaf apex, a solution containing LC99.9 (24.60mg/mL) of the EO was sprayed. After 24h, 72.25% of the larvae had died, indicating stability of the EO when subjected to uncontrolled temperature and humidity conditions. The mechanism of action through which the EO killed the larvae and adult females was investigated by the Bioautographic Method, which showed inhibition of 3.15mg/mL of the EO on the acetylcholinesterase (AChE) enzyme. The results found in the present experiment indicate that E. pyriformis essential oil is an alternative in the control of southern cattle tick in the larval (parasitic) and free-living cycle (non-parasitic) stages under field conditions.(AU)

O Brasil dispõe de um dos maiores rebanhos bovinos comerciais do mundo, sendo natural que junto a esse rebanho, coexista uma enorme quantidade de espécies parasitárias; dentre estes o carrapato Rhipicephalus (Boophilus) microplus que interfere na produtividade animal, causando prejuízos à pecuária de corte e leite. A utilização de acaricidas químicos no controle deste ácaro tem causado o surgimento de populações resistentes e neste sentido, controles alternativos utilizando plantas como fontes de acaricidas botânicos têm se mostrado eficazes. Eugenia pyriformis Cambess é uma planta brasileira com atividades antioxidante e antimicrobiana, entretanto não há relatos da atividade acaricida. O objetivo do presente estudo consistiu na avaliação do potencial acaricida e larvicida do óleo essencial das folhas de E. pyriformis sobre o carrapato bovino nos diferentes estágios do ciclo reprodutivo. As folhas foram coletadas, secas e o OE extraído por hidrodestilação (3 horas) em aparelho Clevenger modificado. A análise química foi realizada por cromatografia gasosa acoplada à espectrometria de massas (CG/EM) sendo identificados 32 compostos, pertencentes à classe sesquiterpenos: hidrocarbonetos (17.98%) e oxigenados (81.96%); tendo como majoritários o spathulenol (43,65%) e caryophylene oxide (12,17%). O OE foi avaliado pelo teste de imersão de adultos nas concentrações (500,00 a 3,12mg/mL) onde foram mensurados os parâmetros: mortalidade das fêmeas (%), eclodibilidade dos ovos (%) e eficiência do produto (%). As larvas foram avaliadas pelo teste de imersão larval (Larval Packet Test) nas concentrações que variaram de 25,00 a 0,00004mg/mL. Foram determinadas as concentrações letais (CLs) necessárias para matar 50 e 99,9% das fêmeas adultas e das larvas utilizando a análise de Probitos. As CL50 e CL99,9 do OE foram (0,06 e 24,60mg/mL) para as larvas e (1.208,80 e 2.538mg/mL) para as fêmeas adultas, respectivamente. Outro parâmetro avaliado em nossa pesquisa foi mensurar a ação do OE no ciclo de vida livre das larvas de R.(B.) microplus; onde as larvas foram depositadas em vasos com Brachiaria decumbens e após migração destas para o ápice das folhas, foi aspergido solução contendo a CL99,9 (24,60mg/mL) do OE. Após 24 horas, 72,25% das larvas morreram indicando que houve estabilidade do OE quando submetido a condições de temperatura e umidade não controladas. O mecanismo de ação pelo qual o OE matou as larvas e fêmeas adultas foi investigado pelo método bioautográfico, indicando uma inibição de 3,15mg/mL do óleo essencial sobre a enzima acetilcolinesterase (AChE). Os resultados encontrados no presente experimento indicaram que o óleo essencial de E. pyriformis é uma alternativa no controle do carrapato bovino no estágio larval (parasitário) e no ciclo de vida livre (estágio não parasitário) em condições de campo.(AU)

Aroma and soluble solid contents of the uvaia-a native Atlantic rainforest fruit-are negatively affected by early harvest.

The uvaia (Eugenia pyriformis Cambess) is a native Atlantic Rainforest Myrtaceae that produces acidic yellow-orange fruit with a peculiar aroma. Its postharvest conservation poses a challenge, due to high perishability. This study investigated the postharvest quality of uvaia fruit during three ripening stages stored at 22ºC. The quality attributes were evaluated: skin color, soluble solids, titratable acidity, flavonoids, carotenoids, phenolic compounds, antioxidant capacity, and volatile compounds at the beginning and end of the fruit's shelf life. Respiration (CO2 ) and C2 H4 production were determined daily. No relationship between ripening stage and respiration was observed, but C2 H4 production increased with ripening stage. Green fruit reached the same skin color, titratable acidity, flavonoids, carotenoids phenolic compounds, and antioxidant activity of mature fruit, also displaying increased shelf life. Green fruit also presented lower soluble solids. The volatile compounds that give green fruit characteristic aroma were persistent. PRACTICAL APPLICATIONS: Aroma and soluble solids content are important factors in determining the fruit quality. This work identified how these factors are affected by early uvaia fruit harvesting. Such information assists in determining the uvaia ideal harvesting point, providing better sensory quality, and increasing the fruit acceptance. Early harvesting at different ripening stages, in addition to prolonging the shelf life of the harvested fruit, is also a tool for understanding physiological processes. This study disseminates unpublished knowledge about uvaia, arousing interest in this native fruit and facilitating its commercialization.

Wild Brazilian species of Eugenia genera (Myrtaceae) as an innovation hotspot for food and pharmacological purposes.

The Myrtaceae is one of the most common plant families in Brazil, including >1000 species of native fruit spread from North to South, where around 50% of all species are endemic to the Atlantic Rain Forest Biome. Most Brazilian species belong to Eugenia, Campomanesia, Psidium and Myrciaria genera. In general, they are characterized by the presence of leaves opposite, simple, entire, with pellucid glands containing ethereal oils and produces berry-like, fleshy fruits with a wide diversity of beneficial characteristics. Several parts of these plants are widely used in regional folk medicine as an astringent, anti-inflammatory, antihypertensive, to treat gastrointestinal disorders, and so on. Some species have already been studied and most of their metabolic effects are attributed to the presence of polyphenols, carotenoids as well as sesquiterpenes and monoterpenes. In addition, the Myrtaceae family has great economic potential, because of the sensory characteristics which encourages their commercial exploitation plus the presence of phytochemicals which play an important role in managing several degenerative chronic diseases besides representing a hotspot of technological innovation for food, cosmetic and pharmaceutical purposes. In this context, this review discusses about the importance of some Eugenia genera representatives such as Eugenia uniflora, Eugenia stipitata, Eugenia brasiliensis, Eugenia pyriformis and Eugenia dysenterica, emphasizing its profile of bioactive compounds as well as the knowledge of the nutritional and functional fruit potential, providing information for further studies aiming to stimulate the cultivation of Brazilian wild berries, for consumption and new food ingredients.

Chemical composition, nutritional value and bioactive compounds in six uvaia accessions.

This study analyzed six uvaia (Eugenia pyriformis Cambess) accessions ('Comum', 'Rugosa', 'Doce de Patos de Minas', 'Pêra', 'Rugosa Doce' and 'Dura') with respect to chemical composition, nutritional value, bioactive compounds and antioxidant capacity. The 'Rugosa Doce' and 'Doce de Patos de Minas' accessions were sweeter (20.18 g 100 g-1 and 18.88 g 100 g-1, respectively), while the 'Rugosa' and 'Pêra' accessions were less acid (0.28 g 100 g-1 and 0.33 g 100 g-1, respectively). Terpenes were the major volatile compounds (46.75%) identified by SPME-GC/MS. The 'Rugosa' accession contained high levels of fibers (43.81 g 100 g-1) and minerals (2235.10  mg 100 g-1). The 'Rugosa Doce' and 'Rugosa' accessions were distinguished by total flavonoids and phenolic compounds. 'Rugosa Doce' and 'Rugosa' may potentially serve as a raw material for food, while 'Doce de Patos de Minas' and 'Pêra' can be used for cosmetic and pharmaceutical industries purposes.

Triagem fitoquímica e avaliação de propriedades biológicas do extrato alcoólico das folhas de eugenia pyriformis cambess. (myrtaceae) / Phytochemical screening and evaluation of biological properties of alcoholic extract of eugenia uvalha cambess. (myrtaceae) leaves

O extrato alcoólico (EUFO) das folhas da espécie nativa Eugenia pyriformis Cambess (Myrtaceae), popularmente conhecida como uvaia, uvalha ou uvaieira, foi avaliado no presente trabalho quanto às atividades citotóxicas, antioxidantes, antibacterianas e anticolinesterásicas, e quanto à constituição fitoquímica. O extrato EUFO mostrou baixa toxicidade pelo bioensaio de letalidade frente à náuplios de Artemia salina Leach (CL50 > 1000 µg mL-1), não sendo considerado citotóxico. As propriedades antioxidantes foram investigadas in vitro pelo método de DPPH e foram consideradas bastante significativas (IC50 = 2,8 µg mL-1), com valor bem próximo ao obtido para o controle positivo quercetina (IC50 = 1,1 µg mL-1). EUFO não mostrou atividade anticolinesterásica pelo ensaio enzimático de inibição de acetilcolinesterase, nem atividade antimicrobiana frente às bactérias Escherichia coli e Staphylococcus aureus. Estes resultados sugerem que as folhas E. pyriformis apresentam baixa toxicidade e possuem componentes com elevado potencial antioxidante, especialmente taninos e flavonoides, podendo ser indicadas em terapias de doenças relacionadas com a presença de radicais livres.

The alcoholic extract (EUFO) of leaves from the native species Eugenia uvalha Cambess (Myrtaceae), popularly known in Brazil as uvaia, uvalha or uvaieira, were evaluated in this study for the cytotoxic, antioxidant, antibacterial and anticholinesterase activities and phytochemical characterization. Its EUFO extract showed low toxicity by the lethality bioassay using Artemia salina Leach (LC50> 1000µg mL-1) and it did not show cytotoxicity. The antioxidant properties were investigated by in-vitro DPPH method and found to be very significant (CI50 = 2.8 µg mL-1), very close to the value obtained for the positive control quercetin (CI50 = 1.1 µg mL-1). The EUFO did not show anticholinesterase activity by enzyme assay of acetylcholinesterase inhibition, or antimicrobial activity against Escherichia coli and Staphylococcus aureus. These results suggest that E. uvalha leaves present low toxicity and have presence of high potential antioxidant components, particularly tannins and flavonoids, which may be indicated in disease therapies associated with the presence of free radicals. This is the first report for the antioxidant activity of E. uvalha.

Extraction and quantification of phenolic acids and flavonols from Eugenia pyriformis using different solvents.

The recovery of phenolic compounds of Eugenia pyriformis using different solvents was investigated in this study. The compounds were identified and quantified by reverse-phase high-performance liquid chromatography coupled with ultraviolet-visible diode-array detector (RP-HPLC-DAD/UV-vis). Absolute methanol was the most effective extraction agent of phenolic acids and flavonols (588.31 mg/Kg) from Eugenia pyriformis, although similar results (p ≤ 0.05) were observed using methanol/water (1:1 ratio). Our results clearly showed that higher contents of phenolic compounds were not obtained either with the most or the least polar solvents used. Several phenolic compounds were identified in the samples whereas gallic acid and quercetin were the major compounds recovered.

Morpho-anatomy of the leaf and stem of Eugenia pyriformis

Eugenia pyriformis Cambess., known as uvaia, is a species of Myrtaceae native to Brazil. Its leaves are used in folk medicine to treat gout because they possess the property of inhibiting xanthine oxidase, an enzyme involved in the conversion of xanthine into uric acid. The objective of this work was to study the leaf and stem morpho-anatomy of E. pyriformis, in order to contribute to what is known about the Brazilian flora, and this medicinal plant and potential vegetal drug. Samples of mature leaves and young stems were fixed and sectioned by freehand, or embedded in glycol methacrylate and sectioned with a microtome, and then stained. In addition, microchemical tests and scanning electron microscopy were performed. The leaf is simple, symmetric, elliptic-lanceolate, with an acute apex and base, and an entire margin. The epidermis is uniseriate and coated with a moderately thick cuticle. The stomata are anomocytic and inserted at the same level as the adjacent cells. Unicellular non-glandular trichomes are abundant on the abaxial surface. The mesophyll is dorsiventral. In transverse section, the midrib is plano-convex and the petiole is circular, and both of these structures have a single bicollateral vascular bundle. In the stem, the vascular cylinder consists of external phloem, xylem and internal phloem, traversed by narrow rays. Phenolic compounds, druses and prismatic crystals of calcium oxalate are also present in the leaf and stem.