Xanthan gum-based edible coating effectively preserve postharvest quality of 'Gola' guava fruits by regulating physiological and biochemical processes.

BACKGROUND: Guava is a fruit prone to rapid spoilage following harvest, attributed to continuous and swift physicochemical transformations, leading to substantial postharvest losses. This study explored the efficacy of xanthan gum (XG) coatings applied at various concentrations (0.25, 0.5, and 0.75%) on guava fruits (Gola cultivar) over a 15-day storage period. RESULTS: The results indicated that XG coatings, particularly at 0.75%, substantially mitigated moisture loss and decay, presenting an optimal concentration. The coated fruits exhibited a modified total soluble soluble solids, an increased total titratable acidity, and an enhanced sugar-acid ratio, collectively enhancing overall quality. Furthermore, the XG coatings demonstrated the remarkable ability to preserve bioactive compounds, such as total phenolics, flavonoids, and antioxidants, while minimizing the levels of oxidative stress markers, such as electrolyte leakage, malondialdehyde, and H2O2. The coatings also influenced cell wall components, maintaining levels of hemicellulose, cellulose, and protopectin while reducing water-soluble pectin. Quantitative analysis of ROS-scavenging enzymes, including superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase, revealed significant increases in their activities in the XG-coated fruits compared to those in the control fruits. Specifically, on day 15, the 0.75% XG coating demonstrated the highest SOD and CAT activities while minimizing the reduction in APX activity. Moreover, XG coatings mitigated the activities of fruit-softening enzymes, including pectin methylesterase, polygalacturonase, and cellulase. CONCLUSIONS: This study concludes that XG coatings play a crucial role in preserving postharvest quality of guava fruits by regulating various physiological and biochemical processes. These findings offer valuable insights into the potential application of XG as a natural coating to extend the shelf life and maintain the quality of guava fruits during storage.

Investigating the impact of Psidium guajava leaf hydroalcoholic extract in improving glutamatergic toxicity-induced oxidative stress in Danio rerio larvae.

Glutamate is one of the predominant excitatory neurotransmitters released from the central nervous system; however, at high concentrations, this substance may induce excitotoxicity. This phenomenon is involved in numerous neuropathologies. At present, clinically available pharmacotherapeutic agents to counteract glutamatergic excitotoxicity are not completely effective; therefore, research to develop novel compounds is necessary. In this study, the main objective was to determine the pharmacotherapeutic potential of the hydroalcoholic extract of Psidium guajava (PG) in a model of oxidative stress-induced by exposure to glutamate utilizing Danio rerio larvae (zebrafish) as a model. Data showed that treatment with glutamate produced a significant increase in oxidative stress, chromatin damage, apoptosis, and locomotor dysfunction. All these effects were attenuated by pre-treatment with the classical antioxidant N-acetylcysteine (NAC). Treatment with PG inhibited oxidative stress responsible for cellular damage induced by glutamate. However, exposure to PG failed to prevent glutamate-initiated locomotor damage. Our findings suggest that under conditions of oxidative stress, PG can be considered as a promising candidate for treatment of glutamatergic excitotoxicity and consequent neurodegenerative diseases.

Bioactive components in Psidium guajava extracts elicit biotoxic attributes and distinct antioxidant enzyme modulation in the larvae of vectors of lymphatic filariasis and dengue.

Control of mosquito vectors, which have caused a global disease burden, has employed various methods. However, the challenges posed by current physical and chemical methods have raised concerns about vector control programs, leading to the search for alternative methods that are less toxic, eco-friendly, and cost-effective. This study investigated the larvicidal potential of aqueous, methanol, and ethylacetate extracts of Guava (Psidium guajava) against Aedes aegypti and Culex quinquefasciatus larvae. Functional group and phytochemical characterization were performed using Fourier-Transform Infrared Spectroscopy (FTIR) and GC-MS analysis to identify the bioactive compounds in the extracts. Larval bioassays were conducted using WHO standard procedures at concentrations of 12.5, 25, 50, 125, and 250 mg/L, and mortality was recorded after 24, 48, and 72 h. Additionally, antioxidant enzyme profiles in the larvae were studied. All of the solvent extracts showed larvicidal activity, with the methanol extract exhibiting the highest mortality against Ae. aegypti and Cx. quinquefasciatus larvae, followed by aqueous and ethylacetate extracts. FTIR spectroscopic analysis revealed the presence of OH, C-H of methyl and methylene, CO and CC. The GC-MS analysis indicated that the methanol, aqueous, and ethylacetate extracts all had 27, 34, and 43 phytoactive compounds that were effective at causing larvicidal effects, respectively. Different concentrations of each extract significantly modulated the levels of superoxide dismutase, catalase, glutathione peroxidase, and reduced glutathione in larvae. This study's findings indicate the potential for developing environmentally friendly vector control products using the bioactive components of extracts from P. guajava leaves.

Topical Antiedematogenic Activity of the Essential Oil of Psidium brownianum Mart. (OEPB) in Murine Ear Edema Models.

Psidium brownianum Mart is reported in the literature by antinociceptive and antioxidant activities, indicating that this species' secondary metabolites might be used to control inflammatory processes. The present study aimed to characterize the topical antiedematogenic activity of the essential oil of Psidium brownianum Mart. (OEPB) in ear edema models by different inflammatory agents. Female Swiss mice (25-35 g) and Wistar albino rats (200-300 g) were used throughout tests (n=6/group) on acute or chronic edema models induced by single and multiple topical applications. The OEPB is administered topically pure or at a concentration of 100 or 200 mg/mL. The antiedematogenic mechanism of OEPB was analyzed by administering capsaicin, arachidonic acid, histamine, and phenol at the best effective dose (200 mg/mL). The results showed a significant reduction of edema-induced single (28.87 %) and multiple (50.13 %) applications of croton oil compared to the negative control group. Regarding potential mechanisms of action, OEPB (200 mg/mL) inhibited the development of edema triggered by capsaicin (29.95 %), arachidonic acid (22.66 %), phenol (23.35 %), and histamine (75.46 %), suggesting an interference with the histaminergic pathway. These results indicate that OEPB presents a topical antiedematogenic effect in acute and chronic murine models, possibly interfering with inflammatory pathways triggered by mediators such as histamine.

Biogenic synthesis of dopamine/carboxymethyl cellulose/TiO2 nanoparticles using Psidium guajava leaf extract with enhanced antimicrobial and anticancer activities.

The green synthesis of metal oxide nanoparticles (NPs) has garnered considerable attention from researchers due to its utilization of eco-friendly solvents during synthesis and cost-effective approaches. This study focuses on the synthesis of titanium oxide (TiO2) and dopamine (DA) carboxymethyl cellulose (CMC)-doped TiO2 (DA/CMC/TiO2) NP using Psidium guajava leaf extract, while also investigating the structural, optical, and morphological and biocidal potential of the prepared NPs. Significantly larger zones of inhibition were observed for DA/CMC/TiO2 NPs compared to TiO2 against various pathogens. Moreover, the MTT assay was carried out to evaluate the anticancer activity of the prepared samples against MG-63 cells, and the results revealed that DA/CMC/TiO2 NPs exhibited significantly higher level of anticancer activity compared to TiO2. The experimental results demonstrated that DA/CMC/TiO2 NPs exhibited enhanced anticancer activity in a dose-dependent manner when compared to TiO2 NPs.

Effect of Novel Processing Techniques on the Carotenoid Release during the Production of Red Guava Juice.

Red guava, distinguished by its elevated lycopene content, emerges as a promising natural source of carotenoids. This study systematically evaluates the impact of diverse processing techniques on the efficient release of carotenoids. The primary objective is to facilitate the transfer of carotenoids into the juice fraction, yielding carotenoid-enriched juice seamlessly integrable into aqueous-based food matrices. The untreated guava puree exhibited a modest release of carotenoids, with only 66.26% of ß-carotene and 57.08% of lycopene reaching the juice. Contrastly, both high-pressure homogenization (HPH) at 25 MPa and enzyme (EM) treatment significantly enhanced carotenoid release efficiency (p < 0.05), while high hydrostatic pressure (HHP) at 400 MPa and pulsed electric field (PEF) of 4 kV/cm did not (p > 0.05). Notably, HPH demonstrated the most substantial release effect, with ß-carotene and lycopene reaching 90.78% and 73.85%, respectively. However, the stability of EM-treated samples was relatively poor, evident in a zeta-potential value of -6.51 mV observed in the juice. Correlation analysis highlighted the interactions between pectin and carotenoids likely a key factor influencing the stable dissolution or dispersion of carotenoids in the aqueous phase. The findings underscore HPH as a potent tool for obtaining carotenoid-enriched guava juice, positioning it as a desirable ingredient for clean-label foods.

Development of gel containing Psidium glaziovianum essential oil has in vitro antimicrobial activity and improves healing of excisional wounds in mice.

Wounds encompass physical, chemical, biological, induced damages to the skin or mucous membranes. In wound treatment, combating infections is a critical challenge due to their potential to impede recovery and inflict systemic harm on patients. Previously, the essential oil extracted from Psidium glaziovianum (PgEO) demonstrated antinociceptive and anti-inflammatory attributes, along with negligible oral toxicity. Hence, our study aimed to assess the effects of topically applying a gel formulation containing PgEO to excisional wounds in mice. Additionally, an in vitro antimicrobial assessment was conducted. The formulated gel underwent characterization and toxicological evaluation on erythrocytes, as well as a dermal irritation test. Its antimicrobial activity was tested against both gram-positive and gram-negative bacteria, as well as fungi. Subsequently, an assessment of its efficacy in excisional wound healing was conducted in mice. The findings of this investigation highlight the gel's efficacy against both gram-positive and gram-negative bacteria, as well as fungi. Moreover, this study underscores that the PgEO-gel treatment enhances skin wound healing, potentially due to its capacity to trigger antioxidant enzymes and suppress pro-inflammatory cytokines. Furthermore, the gel exhibited minimal toxicity to erythrocytes and skin irritation. These findings hold promise for prospective preclinical and clinical trials across diverse wound types. In conclusion, this study sheds light on the potential therapeutic applications of the gel formulation containing essential oil from P. glaziovianum in the context of wound healing.

Guava fibre characterization and effects on digestibility, fermentation products, gastrointestinal transit time and palatability of dry diets for dogs.

The use of fruit fibres as a way of reusing industrial waste is attractive and necessary, increasing the efficiency and reducing the environmental impact of the industry. This study characterized guava fibre as a fibrous ingredient and evaluated its effects when included in extruded diets for dogs on nutrient digestibility, faecal traits, fermentation products, gastrointestinal transit time and palatability. Four diets were formulated: CO (control diet, no fibrous ingredients added), GF3 (3% guava fibre), GF6 (6% guava fibre) and GF12 (12% guava fibre). The guava fibre was added to diets in replacement of maize, with small adjustments in the other ingredients to ensure similar contents of protein and fat. The diets were fed to 24 adult Beagle dogs (6 per diet) during 15 days for adaptation followed by 15 days for assessment of digestibility, fermentation end products and gastrointestinal transit time. The palatability of G6 and G12 treatments was evaluated against the CO by the two-pan test. Results were compared by analysis of variance and polynomial contrasts according to the guava fibre inclusion level (p < 0.05). The addition of guava fibre did not change nutrient intake except for the increase on dietary fibre (p < 0.001). Fibre inclusion resulted in a quadratic reduction in total tract apparent digestibility for dry matter, organic matter, crude protein and crude energy (p < 0.001), and on the metabolizable energy content of the foods (p < 0.001). Guava fibre addition did not change the faecal concentration of ammonia, lactic acid, faecal pH and branched chain fatty acids but it decreased acetic and propionic acids concentration (p < 0.01). The inclusion of 12% guava fibre did result in a faster transit time (p = 0.046) compared to the control diet. Guava fibre can be characterized as a novel insoluble non-fermentable fibre source that could be safely used in levels up to 12% in canine extruded diets.

Effects of mixed extract from two tropical plants on gut microbiome and metabolome in piglets.

In this study, we performed a quantitative analysis of 12 compounds derived from Piper sarmentosum extract (PSE) and guava leaf extract (GE). In addition, we investigated the effects of mixed extract (ME) of PSE and GE (1:1) on piglets' gut microbiome and metabolome. A total of 200 piglets (Duroc × Landrace × Large Yorkshire, 21-day-old) were randomly assigned into two groups with five replicates of 20 piglets/pen having the same initial body weight. Piglets were fed a basal diet supplemented with ME at 0 (T0) or 200 mg/kg (T1) for 3 weeks. The quantitation results by ultraperformance liquid chromatography linked to triple-quadrupole tandem mass spectrometry showed that vitexin 2-O-rhamnoside and pellitorine were the greatest abundant among six compounds detected in the PSE. In addition, quercetin, isoquercitrin and avicularin were found to be the richest of all detected compounds in the GE. Findings on experimental animals indicated that three differential metabolites, comprising L-alanine, sarcosine and dihydrofolic acid, in T1 compared with T0 groups, have exactly opposite levels trends in serum and faeces. Moreover, two metabolic pathways (i.e., urea cycle and glutamate metabolism) differed significantly in the serum and faeces of piglets between T0 and T1 (p < 0.05). At the same time, T1 had significantly higher relative abundances of Agathobacter and Alloprevotella than T0 at genus level (p < 0.05). Correlation analysis revealed that the genus Agathobacter correlated positively with carbamoyl phosphate (p < 0.01) and oxoglutaric acid (p < 0.05), and negatively with succinic acid (p < 0.01) and ornithine (p < 0.05). These four differential metabolites were also involved in the urea cycle and/or glutamate metabolism pathways. The results here indicated that the tested plant extract mixture represents a worthy feed additive with obvious antioxidative properties.

Detecting fungi-affected multi-crop disease on heterogeneous region dataset using modified ResNeXt approach.

Crop diseases pose significant threats to agriculture, impacting crop production. Biotic factors contribute to various diseases, including fungal, bacterial, and viral infections. Recent advancements in deep learning present a novel approach to the detection and recognition of these crop diseases. While considerable research has focused on identifying and recognizing crop diseases, fungal disease-affected crops have received relatively less attention and also detecting disease on different region datasets. This paper is about spotting fungal diseases in crops across different regions with diverse climates. It emphasizes the need for tailored detection methods, addressing the risk of mycotoxin production by fungi, which can harm both humans and animals. Detecting fungal diseases in apple, guava, and custard apple crops such as spot, scab, rust, rot, leaf spot, and insect ate. In the proposed work, the modified ResNeXt variant of the convolution neural network (CNN) technique was employed to predict 3 major crop classes of fungal disease. Initially, using Inception-v7 and ResNet for fungal disease in crops did not yield satisfactory results. A modified ResNeXt CNN model was proposed, showing improved fungal disease prediction. The novel model underwent a comparison with established methodologies. The suggested model draws upon a benchmark dataset consisting of 14,408 images capturing fungal diseases, categorized into three distinct classes: apple, custard apple, and guava. Experimental outcomes show that the proposed mutated ResNeXt model outperformed the state-of-the-art approaches. The model achieved 98.92% accuracy and high performance across recall, precision, and F1-score (above 99%) for the benchmark dataset, which gained encouragement and was comparable with the state-of-the-art approach.

Biomonitoring potentially toxic elements in atmospheric particulate matter of greater Dhaka region using leaves of higher plants.

In this study, four different plant species, namely Artocarpus heterophyllus, Mangifera indica, Psidium guajava, and Swietenia mahagoni, were selected from seven different locations to assess the feasibility of using them as a cost-effective alternative for biomonitoring air quality. Atmospheric coarse particulate matter (PM10), soil samples, and leaf samples were collected from residential, industrial, and traffic-congested sites located in the greater Dhaka region. The heavy metal concentrations (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in the leaves of the different species, PM10, and soil samples were analyzed. The highest Pb (718 ng/m3) and Zn (15,956 ng/m3) concentrations were found in PM10 of Kodomtoli which is an industrial area. On the other hand, the highest Fe (6,152 ng/m3) and Ni (61.1 ng/m3) concentrations were recorded in the PM10 of Gabtoli, a heavy-traffic area. A significant positive correlation (r = 0.74; p < 0.01) between Pb content in plant leaves and PM fraction was found which indicated that atmospheric PM-bound Pb may contribute to the uptake of Pb by plant leaves. The analysis of the enrichment factor (EF) revealed that soils were contaminated with Cd, Ni, Pb, and Zn. The abaxial leaf surfaces of Psidium guajava growing at the polluted site exhibited up to a 40% decrease in stomatal pores compared to the control site. Saet's summary index (Zc) demonstrated that Mangifera indica had the highest bioaccumulation capacity. The metal accumulation index (MAI) was also evaluated to assess the overall metal accumulation capacity of the selected plants. Of the four species, Swietenia mahagoni (3.05) exhibited the highest MAI value followed by Mangifera indica (2.97). Mangifera indica and Swietenia mahagoni were also found to accumulate high concentrations of Pb and Cr in their leaves and are deemed to be good candidates to biomonitor Pb and Cr contents in ambient air.

Probiotic Yogurt Supplemented with Lactococcus lactis R7 and Red Guava Extract: Bioaccessibility of Phenolic Compounds and Influence in Antioxidant Activity and Action of Alpha-amylase and Alpha-glucosidase Enzymes.

The industry has increasingly explored the development of foods with functional properties, where supplementation with probiotics and bioactive compounds has gained prominence. In this context, the study aimed to evaluate the influence of in vitro biological digestion on the content of phenolic compounds, antioxidant activity, and inhibition of α-amylase and α-glucosidase activities of probiotic yogurt supplemented with the lactic acid bacteria Lactococcus lactis R7 and red guava extract (Psidium cattleianum). A yogurt containing L. lactis R7 (0.1%) and red guava extract (4%) was characterized for the content of phenolic compounds, antioxidant activity, and potential for inhibition of digestive enzymes after a simulated in vitro digestion process. After digestion, the caffeic and hydroxybenzoic acids remained, and sinapic acid only in the last digestive phase. Antioxidant activity decreased during digestion by 28.93, 53.60, and 27.97% for DPPH, nitric oxide and hydroxyl radicals, respectively, and the inhibition of the α-amylase enzyme decreased only 4.01% after the digestion process. α-glucosidase was more efficient in intestinal digestion, demonstrating an increase of almost 50% in probiotic yogurt with red guava extract before digestion. Possibly, the phenolics change their conformation during digestion, generating new compounds, reducing antioxidant activity, and increasing the inhibitory activity of α-glucosidase digestive enzymes. It was concluded that the probiotic yogurt formulation supplemented with red guava extract could interfere with the concentration of phenolic compounds and the formation of new compounds, suggesting a positive and effective inhibition of the digestive enzymes, even after the digestive process.

Chemical Constituents and Antioxidant Potential of Red Guava (Psidium cattleianum Sabine) from Southern Brazil in Different Edible Ripening Stages.

Ripening and growing location are important factors that can impact fruit quality characteristics. In this study, the influence of these factors on physicochemical characteristics, carbohydrates, aliphatic organic acids, phenolic compounds, and antioxidant capacity of red guava (Psidium cattleianum Sabine) was evaluated. Fruit ripening increased fructose and glucose (up to 22.83 and 16.42 g 100 g- 1 dry matter (DM), respectively), and decreased citric acid, the major organic acid (up to 135.35 mg g- 1 DM). Ripening and growing location also influenced the concentration of phenolic compounds and antioxidant capacity of red guava, in which a dependency between both factors was observed in most cases. Apigenin, galangin, isoquercitrin, among other phenolic compounds were quantified for the first time in red guava, in which isoquercitrin was the major (up to 13409.81 mg kg- 1 DM). The antioxidant potential of red guava was also confirmed by ferric reducing antioxidant power assay (up to 82.63 µmol Fe+ 2 g- 1 DM), Folin-Ciocalteu reducing capacity assay (up to 17.79 mg gallic acid equivalent g- 1 DM), and DPPH free radical scavenging assay (up to 25.36 mg ascorbic acid equivalent g- 1 DM). These results especially demonstrated the bioactive potential of red guava and provided knowledge regarding the influence of ripening and growing location on chemical and bioactive components encouraging its industrial exploitation.

Efficient reduction of Cr(VI) by guava (Psidium guajava) leaf extract and its mitigation effect on Cr toxicity in rice seedlings.

Hexavalent chromium (Cr(VI)) is a toxic element that has negative impacts on crop growth and yield. Using plant extracts to convert toxic Cr(VI) into less toxic Cr(III) may be a more favorable option compared to chemical reducing agents. In this study, the potential effects and mechanisms of using an aqueous extract of Psidium guajava L. leaves (AEP) in reducing Cr(VI) toxicity in rice were comprehensively studied. Firstly, the reducing power of AEP for Cr(VI) was confirmed by the cyclic voltammetry combined with X-ray photoelectron spectroscopy (XPS) assays. The highest Cr(VI) reduction efficiency reached approximately 78% under 1.5 mg gallic acid equivalent (GAE)/mL of AEP and 10 mg/L Cr(VI) condition. Additionally, Cr(VI) stress had a significant inhibitory effect on rice growth. However, the exogenous application of AEP alleviated the growth inhibition and oxidative damage of rice under Cr(VI) stress by increasing the activity and level of enzymatic and non-enzymatic antioxidants. Furthermore, the addition of AEP restored the ultrastructure of root cells, promoted Cr adsorption onto root cell walls, and limited the translocation Cr to shoots. In shoots, AEP application also triggered the expression of specific genes involved in Cr defense and detoxification response, including photosynthesis pathways, antioxidant systems, flavonoids biosynthesis, and plant hormone signal transduction. These results suggest that AEP is an efficient reduction agent for Cr(VI), and exogenous application of AEP may be a promising strategy to mitigate the harm of Cr(VI) on rice, ultimately contributing to improved crop yield in Cr-contaminated environments.

Analytical assessment of modulated electric flux triggered degradation of chlorfenapyr and deltamethrin pesticides in guava fruits.

The purpose of this study was to explore the new effective method and investigate the dissipation of chlorfenapyr and deltamethrin (DM) pesticides used in the treatment of guava fruit from tropical and sub-tropical areas of Pakistan. Five different solutions of varying concentrations of pesticides were prepared. This study involved the in-vitro and in-vivo analysis of modulated electric flux-triggered degradation as an efficient method for the safer degradation of selected pesticides. The Taser gun was used as a tool for providing different numbers of electrical shocks of million voltages to the pesticides present in guava fruit at different temperatures. The degraded pesticides were extracted and analyzed by High-performance liquid chromatography (HPLC). The HPLC chromatograms verified that significant dissipation of pesticides took place when these were exposed to 9 shocks at 37 °C, which proved the efficiency of this degradation method. More than 50% of the total spray of both pesticides was dissipated. Thus, modulated electrical flux-triggered degradation is one of the effective methods for pesticide degradation.

Guava (Psidium guajava L.): a glorious plant with cancer preventive and therapeutic potential.

Guava (Psidium guajava L.) tree (Myrtaceae family) bears fruit rich in vitamins, fiber, and other nutrients. While native to Latin America, guava is grown in many tropical and subtropical regions across the globe where it has long been used in traditional medicine to treat a myriad of ailments. Guava has been shown to exhibit a number of biological and pharmacological activities, such as antioxidant, anti-inflammatory, immunomodulatory, antimicrobial, antidiabetic, and anticancer properties. Several parts of the plant, including the leaves, fruits, seeds, peels, pulp, bark, and oil, produce phytochemicals with medicinal properties. Emerging research has found that guava bioactive phytochemicals exert antitumorigenic effects against various human malignancies through multiple mechanisms. While there are numerous individual studies that document the anticancer effects of guava constituents, an up-to-date, comprehensive, and critical review of available research data has not been performed. Therefore, the purpose of this review is to present a complete analysis of the cancer preventive and anticancer therapeutic potential of guava-derived products and guava constituents, with a focus on the cellular and molecular mechanisms of action. The bioavailability, pharmacokinetics, and toxicity of guava as well as limitations, challenges, and future directions of research have also been discussed.

Psidium cattleianum fruit extract prevents systemic alterations in an animal model of type 2 diabetes mellitus: comparison with metformin effects.

Objective: In this study, we aimed to determine the role of Psidium cattleianum extract (PCE) and compare its effects with those of metformin (Met) in an animal model with type 2 diabetes mellitus (T2DM).Methods: T2DM was induced in rats using a high-fat diet (HFD), followed by a single dose of streptozotocin (STZ). Met and PCE were administered intragastrically once a day throughout the experiment, and their effects on biochemical, inflammatory, oxidative, and histological parameters were evaluated.Results: Met and PCE prevented the increase in serum levels of glucose, total cholesterol (TC), triacylglycerol (TG), very low-density lipoprotein (VLDL) and interleukin-6 (IL-6) induced by T2DM, and restored redox homeostasis in the liver and brain. Met increased the serum levels of anti-inflammatory cytokine and interleukin-10 (IL-10). Furthermore, both treatments restored the liver and pancreas from marked cellular disorganisation, vacuolisation, and necrosis, with PCE being more effective than Met in recovering histological changes.Conclusion: PCE is a promising agent for the prevention of T2DM complications.

Psidium guajava L.- dichloromethane and ethyl acetate fractions ameliorate striped catfish (Pangasianodon hypophthalmus) status via immune response, inflammatory, and apoptosis pathways.

Psidium guajava L. is known to possess immune-modulatory properties in humans and other mammals. Although the positive effects of P. guajava-based diets on the immunological status have been shown for some fish species, the underlying molecular mechanisms of its protective effects remain to be investigated. The aims of this study were to evaluate the immune-modulatory effects of two guava fractions from dichloromethane (CC) and ethyl acetate (EA) on striped catfish with in vitro and in vivo experiments. Striped catfish head kidney leukocytes were stimulated with 40, 20, 10 and 0 µg/ml of each extract fraction, and the immune parameters (ROS, NOS, and lysozyme) were examined at 6 and 24 h post stimulation. A final concentration of each fraction at 40, 10 and 0 µg/fish was then intraperitoneally injected into the fish. After 6, 24, and 72 h of administration, immune parameters as well as the expression of some cytokines related to innate and adaptive immune responses, inflammation, and apoptosis were measured in the head kidney. Results indicated that the humoral (lysozyme) and cellular (ROS and NOS) immune endpoints were regulated differently by CC and EA fractions depending on dose and time in both, in vitro and in vivo experiments. With regards to the in vivo experiment, the CC fraction of the guava extract could significantly enhance the TLRs-MyD88-NF-κB signaling pathway by upregulating its cytokine genes (tlr1, tlr4, myd88, and traf6), following the upregulation of inflammatory (nfκb, tnf, il1ß, and il6) and apoptosis (tp53 and casp8) genes 6 h after injection. Moreover, fish treated with both CC and EA fractions significantly enhanced cytokine gene expression including lys and inos at the later time points - 24 h or 72 h. Our observations suggest that P. guajava fractions modulate the immune, inflammatory, and apoptotic pathways.

The improvement of guava (Psidium guajava) juice quality using crude multi-enzymatic extracts obtained from yeasts.

Guava juice is cloudy and viscous, which hinders filtration, decreases yield, and causes the loss of quality after its processing and during storage. This study aimed to evaluate enzymatic treatment effects using crude multi-enzymatic extracts (CME) obtained from Rhodotorula mucilaginosa, Rhodotorula orizycola, and Pseudozyma sp. produced by submerse fermentation in the extraction of juice guava. Mixtures of 100 ml of guava pulp and multi-enzymatic extracts proposed by Doehlert planning were incubated under constant agitation at 150 rpm and 50°C, and a Doehlert design was applied as a multivariate optimization strategy. The optimal conditions using the multi-enzymatic extract were: 0.4% (v/v) of CME for 131 min for the multi-enzymatic treatment using Pseudozyma sp.; 3.0% (v/v) of CME for 154 min using the R. mucilaginosa CME; and 5.0% (v/v) of CME for 90 min using R. oryzicola. The maximum viscosity reduction values for the juices treated with the CME of yeasts were 10.33%, 86.38%, and 13.33% for the juices treated with the CME of Pseudozyma sp., R. mucilaginosa, and R. orizycola, respectively. The physical-chemical properties were improved after treatment with CMEs, yielding a reduction of clarity, increase of total soluble solids and reducing sugars, and decreasing the acidity (pH) for all treatments with enzymatic extracts of all strains. The yeasts studied showed a potential for CME production to be applied to juice, improving the quality of the juice, and R. mucilaginosa was the most prominent yeast due to most significant reduction of viscosity in guava juice.

Evaluation of 28-day repeated doses oral toxicity of essential oil from Psidium glaziovianum Kiaersk leaves on various biological parameters in Swiss mice.

Only a small number of the many medicinally important species in the genus Psidium L. have had their safety assessed. Psidium glaziovianum, a plant native to Brazil, is reported to exert antinociceptive and anti-inflammatory effects; however, there are no apparent reports of long-term safety following administering of repeated doses. The aim of this study was to examine the effects of 28-day oral of treatment at 250, 500 or 1,000 mg/kg Psidium glaziovianum essential oil (PgEO) on behavioral and physiological parameters in male and female Swiss mice. First, PgEO was chemically characterized by gas chromatography mass spectrometry (GC-MS). The following parameters were examined: motor activity, body temperature, blood glucose, urine, hematology, biochemistry, histology, and oxidative stress. Characterization of PgEO revealed 48 components which were dominated by sesquiterpenes 1,8-cineol (24.29%), α-pinene (19.73%) and ß-pinene (17.31%). Data showed that PgEO treatment in mice increased activities of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) without markedly affecting body weight, hematological or biochemical parameters, as well as water or food consumption. Administration of PgEO in repeated daily dosages over 28 days did not significantly alter exploratory or locomotor activities. Based upon our findings, PgEO administration daily for 28 days, exhibited low toxicity and absence of effects on the nervous system. Data demonstrated that PgEO produced hypoglycemic and antioxidant actions which need to be considered in safety assessment.