Anxiolytic and Antianhedonic-like Effects of Psidium guajava Leaf in Alcohol-Withdrawn Mice.

Objectives: Alcohol withdrawal syndrome manifests through a range of symptoms, including anxiety and anhedonia, significantly affecting the quality of life of those affected. This study investigates the potential therapeutic effects of the methanolic extract of Psidium guajava leaves (MPG) on anxiety and anhedonia in Swiss albino female mice undergoing alcohol withdrawal. Methods: Four groups of mice underwent alcohol withdrawal, with one group undergoing saline withdrawal as a control. On the test day, behavioral assessments were conducted to evaluate anxiety and anhedonia. Groups I and II received sodium carboxymethylcellulose, Group III received diazepam, and Groups IV and V received varying oral doses of MPG. Results: The results indicate significant anti-anhedonic and anxiolytic effects of MPG. These effects were observed through changes in parameters measured in the Open Field test, Elevated Plus Maze test, Marble Burying test, and Sucrose Preference test. Mice treated with MPG displayed reduced anxiety-like behaviors and increased sucrose preference compared to untreated mice undergoing alcohol withdrawal. Conclusion: These findings suggest that Psidium guajava leaf extract may have therapeutic potential in alleviating anxiety and anhedonia associated with alcohol withdrawal. The observed effects indicate that MPG could serve as a promising adjunct therapy for managing alcohol withdrawal symptoms, thereby enhancing the overall well-being of individuals undergoing alcohol cessation.

Guaijaverin and Epigallocatechin Gallate Complex Modulate Th1 and Th2 Cytokine-Mediated Allergic Responses Through STAT1/T-bet and STAT6/GATA3 Pathways.

We aimed to determine the in vitro and in vivo synergistic antiallergic effect of guaijaverin and epigallocatechin gallate (EGCG) complex (GEC), and the antiallergic rhinitis (AR) properties of guaijaverin-rich Psidium guajava and EGCG-rich Camellia sinensis (ILS-F-2301). GEC showed synergistic inhibition of ß-hexosaminidase by 4.20% and interleukin (IL)-4, -5, and -13 by 4.08%, 0.67%, and 4.71%, respectively, while increasing interferon (IFN)-γ by 12.43%, compared with EGCG only. In addition, 50 µg/mL of ILS-F-2301 inhibited ß-hexosaminidase release, and inhibited IL-4, -5, and -13 by 61.54%, 58.79%, and 59.25%, respectively, while increasing IFN-γ (showing 133.14% activation). Moreover, 50 µg/mL of ILS-F-2301 suppressed p-STAT6 and GATA3, while p-STAT1 and T-bet increased, and 0.039 µg/mL of guaijaverin or 5.275 µg/mL of EGCG modulated T helper (Th)1- and Th2-related proteins. These data suggested that guaijaverin and EGCG in ILS-F-2301 was the main active compound involved in Th1/Th2 modulation. In the AR mouse model, the administration of ILS-F-2301 inhibited ovalbumin (OVA)-specific IgE, histamine in serum; it also inhibited IL-4 and -5 by 28.23% and 47.15%, respectively, while increasing IFN-γ (showing 37.11% activation), compared with OVA/Alu-treated mice. Taken together, our findings suggest that ILS-F-2301 is a functional food for alleviating anti-AR.

Psidium guajava Seed Oil Reduces the Severity of Colitis Induced by Dextran Sulfate Sodium by Modulating the Intestinal Microbiota and Restoring the Intestinal Barrier.

The oil derived from Psidium guajava seeds (TKSO) exhibits an abundance of diverse unsaturated fatty acids, notably oleic, linoleic, and α-linolenic acids, conferring substantial health advantages in addressing metabolic irregularities and human diseases. This research endeavor focused on elucidating the impacts of TKSO on colonic inflammatory responses and intestinal microbiota alterations in a murine model of colitis induced by dextran sulfate sodium (DSS), demonstrated that substantial supplementation with TKSO reduces the severity of colitis induced by DSS. Furthermore, TKSO effectively attenuated the abundance and expression of proinflammatory mediators while augmenting the expression of tight junction proteins in DSS-challenged mice. Beyond this, TKSO intervention modulated the intestinal microbial composition in DSS-induced colitis mice, specifically by enhancing the relative presence of Lactobacillus, Norank_f_Muribaculaceae, and Lachnospiraceae_NK4A136_group, while concurrently diminishing the abundance of Turicibacter. Additionally, an analysis of short-chain fatty acids (SCFAs) revealed noteworthy elevations in acetic, propionic, isobutyric, and butyric acids, and total SCFAs levels in TKSO-treated mice. In summary, these findings underscore the potential of TKSO to reduce the severity of colitis induced by DSS in mice through intricate modulation of the intestinal microbiota, metabolite profiles, and intestinal barrier repair, thereby presenting a promising avenue for the development of therapeutic strategies against intestinal inflammatory conditions.

Guaijaverin And Epigallocatechin Gallate Exerts Antiinflammatory And Antiallergenic Effects Through Interleukin-12 Production.

Our aim in the current study was to determine the in vitro and in vivo synergistic antiinflammatory and antiallergic effect associated with the IL-12 production of guaijaverin and epigallocatechin gallate (EGCG) complex (GEC) and ILS-F-2301 (2:8 extract of Psidium guajava and Camellia sinensis). Compared to EGCG alone, GEC showed synergistic inhibition of nitric oxide (NO), inducible NO synthase, and cyclooxygenase-2 by 3.8, 5.1, and 4.1%, respectively. The downregulation of interleukin-12 (IL-12) by 2,4-dinitrophenyl-human serum albumin conjugate/DNP-immunoglobulin E or ovalbumin (OVA) was synergistically increased by GEC by about 7.5% or 5.4% compared to EGCG alone. The level of downregulation of IL-12 in plasma increased by 100 mg/kg with ILS-F-2301 (28.7%) when compared to the OVA/Alu-treated group. Also, GEC synergistically increased by GEC by about 7.5% or 5.4% compared to EGCG alone. The level of down and cyclooxygenase C synergistically inhibited p-Akt, PI3K, mTOR, p-STAT6, and GATA3 by 4.9%, 4.1%, 19.2%, 23.8%, and 35.3%, respectively, while increasing the expressions of p-STAT1 and T-bet (showing 53.3% and 9.4% activation) when compared to EGCG alone. In an allergenic rhinitis mouse model, 100 mg/kg of ILS-F-2301 was shown to inhibit p-Akt, PI3K, mTOR, p-c-Jun N-terminal kinase (p-JNK), p-extracellular signal-regulated kinase (p-ERK), and p-p38 by 23.3%, 43.8%, 17.2%, 32.2%, 29.1%, and 41.8% when compared to the OVA/Alu-sensitized group. Taken together, our findings suggest that ILS-F-2301 may have potential as a functional food for alleviating antiallergic rhinitis.

Ethnobotany, phytochemistry, and biological activities of Psidium guajava in the treatment of diarrhea: a review.

Psidium guajava: is a tropical tree that is widely used in traditional medicine, especially for treating diarrhea. While P. guajava has been the subject of numerous reviews, none have specifically examined its ethnobotany, pharmacology, and phytochemistry in relation to its antidiarrheal activity. This review aims to summarize the evidence of effectiveness and safety of P. guajava in the treatment of diarrhea. Literature searches were conducted through Web of Science, PubMed, and ScienceDirect by using keywords "Psidium guajava" and "diarrhea" in October 2022. A total of 189 studies were included in this review. P. guajava is widely used in traditional medicine in 44 countries. Decoction and oral were the most represented method of preparation and administration, respectively, while leaves represented the most frequently cited part of the plant. Around 27 antidiarrheal or antibacterial compounds have been isolated and identified, including benzophenone glycosides, terpenes, polysaccharides, phenols, and flavonoids. This article presents ethnobotanical and pharmacological evidence for the efficacy of P. guajava leaves in the treatment of diarrhea and provides reference information for further investigation of this plant. However, despite the large number of publications on the topic, there are still some questions to answer: are quercetin and its glycosides the only ones to act as antidiarrheal agents? What is the mechanism of action of P. guajava antidiarrheal compounds? are the use of guava leaves safe in all types of populations including children, and at what dosage? To answer these questions, more complete phytochemical studies and systematic clinical trials are needed.

A novel edible coating based on Albizia [Albizia lebbeck (L.) Benth.] gum delays softening and maintains quality of harvested guava fruits during storage.

Guava, a commercially important fruit crop, is being grown in tropical and subtropical regions around the world. Due to the perishable nature of guava fruits, there are great losses during marketing, transport and storage. The application of edible coating is emerging as a low-cost, simple to implement and efficient method for extending the postharvest life of fresh horticultural produces, such as fruits and vegetables. This study aimed to assess the potential of Albizia gum (AZG) to improve storability and maintain the overall fruit quality of stored guava fruits. Freshly harvested guava fruits were coated with 0 % (control), 1.5 %, 3 % or 4.5 % AZG. After coating treatment, the fruits were stored at 20 ± 1 °C and 85-90 % relative humidity for 15 days. The results revealed that 4.5% AZG coating suppressed the weight loss and decay incidence up to 27 % and 36 %, respectively, as compared with control. The fruits coated with 4.5 % AZG had the maximum titratable acidity (0.40 %), ascorbic acid (104.47 mg·100 g-1), total antioxidants (118.84 mmol Trolox·100 g-1), total phenolics (285.57 mg·kg-1) and flavonoids (60.12 g·kg-1) on 15th day of storage. However, the minimum total soluble solids (11.97 %), sugar-acid ratio (29.31), relative ion leakage (68.40 %), malondialdehyde (0.11 nmol·kg-1 FW) and hydrogen peroxide (16.05 µmol·kg-1 FW) were recorded in the fruits of same treatment on 15th day of storage. Furthermore, the activities of antioxidant enzymes "i.e., superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX)" were increased under the influence of AZG coating. Consequently, as compared to uncoated fruits, AZG-coated fruits exhibited reduced activities of fruit softening enzymes "i.e., cellulase, pectin methylesterase (PME), and polygalacturonase (PG)". To sum up, the application of AZG-based edible coating could markedly improve the storage life of guavas and maintain overall fruit quality.

Dataset explaining the comparative seasonal crop load and harvest quality of guava upon pruning strategies.

The dataset explained the details on how pruning techniques significantly affected the seasonal variations on fruit availability and edible quality of guava (Psidium guajava L.) under fluctuating sub-tropical weather conditions. The present pruning data also directed a way of enhancing lean season (off-season) harvest without sacrificing the main season yield and fruit quality. In detail, the pruning strategies included branch removal of 0 cm, 15 cm, 30 cm and 45 cm from shoot-tip once a year during spring (early March), monsoon (early June) and autumn (early September) starting with spring pruning. Over two consecutive years (2019-2020 and 2020-2021), the pruning treatments were assigned in triplicates following a randomized Complete Block Design (RCBD) where the same plants received the same treatments during observation period. Data on crop load like number of fruits and fruit yield per plant and fruit biochemical traits namely total soluble solids, titratable acidity, total sugars, vitamin C and fruit specific gravity were recorded. To assess the seasonal variations, data collection was performed continuously and grouped at quarter intervals i.e., March-May, June-August, September-November and December-February of the year. Plants under pruning produced greater number of flowers and fruits for superior yield and quality compared to non-pruned plants. Irrespective of pruning techniques, June-August and September-November quarters had superior yield over others, whereas March-May harvests retained utmost fruit quality. Considering pruning time, plants reserved maximum harvestable fruits in June-August quarter under spring pruning followed by March-May quarter for autumn pruning compared to other combinations. Moreover, fruit biochemical attributes were examined the best at March-May harvests under autumn pruning. Alongside, June-August and September-November periods exhibited superiority for yield over others when plants were pruned at 30 cm level, but 45 cm pruning had best yield at March-May quarter. Whether, fruits had notable TSS, sugars, vitamin C and specific gravity obtained during March-May period from 45 cm pruning treatment. June-August was noted to produce inferior quality fruits in guava.

Functional assessments of Psidium guajava L. and Morus alba L. leaf extracts on postprandial glucose control.

Diabetes is a leading cause of death, according to statistics published by the Department of Health, Executive Yuan of Taiwan. In modern medicine, diabetes can be controlled using various medications; however, some drugs often have undesirable side effects. It therefore became a goal to find plant-based material that can reduce glucose concentration in the blood while reducing the incidence of complications and not causing side effects. Alpha-glucosidase inhibitors (AGIs) are effective glucose-lowering medicines and are enzymes essential to carbohydrate digestion. Inhibition of α-glucosidase leads to a delayed and reduced rise in postprandial blood glucose levels. This study evaluates the inhibitory effect of mixed extracts of Psidium guajava L. and Morus alba L. leaves on α-glucosidase activity and postprandial hyperglycemia in normal and diabetic rats. The inhibition of α-glucosidase activity was assayed in vitro. Half maximal inhibitory concentration (IC50) values of Psidium guajava L. and Morus alba L. were 2.25 and 0.1 mg/mL, respectively. The IC50 value of a commercial anti-hyperglycemic agent (Glucobay) is 6.41 mg/mL. The IC50 value of a mixture of extracts of Psidium guajava L. and Morus alba L. was 0.07 mg/mL. In cytotoxicity tests, survival percentages and shape did not significantly affect the murine embryonic liver cell line (BNL CL.2) when treated with varying concentrations of mixture extracts for varying periods of time. In summary, Psidium guajava L. and Morus alba L. showed positive anti-diabetes activity and suggested promising potential for alternative functional foods for diabetes mellitus (DM) patients.

Use of Proline to Induce Salt Stress Tolerance in Guava.

Guava is a fruit tree with high potential in the semi-arid region of northeast Brazil. However, qualitative and quantitative water scarcity is a limiting factor for the expansion of irrigated agriculture. Thus, it is necessary to use techniques to mitigate the effects of salt stress, such as foliar application of proline. The objective of this study was to evaluate the effect of foliar application of proline as a mitigator of salt stress effects on the morphophysiology of guava cv. Paluma. The experiment was carried out under field conditions at the 'Rolando Enrique Rivas Castellón' Experimental Farm in São Domingos, PB, Brazil, using a randomized block design in a 5 × 4 factorial scheme referring to five levels of electrical conductivity of irrigation water, ECw (0.8, 1.5, 2.2, 2.9, and 3.5 dS m-1) and four concentrations of proline (0, 8, 16, and 24 mM). Salinity above 0.8 dS m-1 compromised gas exchange, photosynthetic pigment synthesis, photochemical efficiency, and growth of guava plants at 360 days after transplanting. Foliar application of proline at a concentration of 24 mM mitigated the effect of salt stress on the relative water content, stomatal conductance, and carotenoid contents in plants irrigated with 3.6 dS m-1 water. Meanwhile, a proline concentration of up to 18 mM resulted in higher transpiration, CO2 assimilation rate, instantaneous carboxylation efficiency, and absolute growth rate in stem diameter under ECw of 0.8 dS m-1. Proline concentration of up to 24 mM increased the biosynthesis of photosynthetic pigments and the relative growth rate in stem diameter of guava in the period from 190 to 360 days after transplanting.

Computational Evaluation on the Interactions of an Opaque-Phase ABC Transporter Associated with Fluconazole Resistance in Candida albicans, by the Psidium guajava Bio-Active Compounds.

Objectives: Candida albicans is an opportunistic pathogen that occurs as harmless commensals in the intestine, urogenital tract, and skin. It has been influenced by a variety of host conditions and has now evolved as a resistant strain. The aim of this study was thus detect the fluconazole resistant C. albicans from the root caries specimens and to computationally evaluate the interactions of an opaque-phase ABC transporter protein with the Psidium guajava bio-active compounds. Methods: 20 carious scrapings were collected from patients with root caries and processed for the isolation of C. albicans and was screened for fluconazole resistance. Genomic DNA was extracted and molecular characterization of Cdrp1 and Cdrp2 was done by PCR amplification. P. guajava methanolic extract was checked for the antifungal efficacy against the resistant strain of C. albicans. Further in-silico docking involves retrieval of ABC transporter protein and ligand optimization, molinspiration assessment on drug likeness, docking simulations and visualizations. Results: 65% of the samples showed the presence of C.albicans and 2 strains were fluconazole resistant. Crude methanolic extract of P. guajava was found to be promising against the fluconazole resistant strains of C. albicans. In-silico docking analysis showed that Myricetin was a promising candidate with a high docking score and other drug ligand interaction scores. Conclusion: The current study emphasizes that bioactive compounds from Psidium guajava to be a promising candidate for treating candidiasis in fluconazole resistant strains of C. albicans However, further in-vivo studies have to be implemented for the experimental validation of the same in improving the oral health and hygiene.

Guava leaf extract attenuated muscle proteolysis in dexamethasone induced muscle atrophic mice via ubiquitin proteasome system, mTOR-autophagy, and apoptosis pathway.

Muscle atrophy is the waste or loss of muscle mass and is caused by physical inactivity, aging, or diseases such as diabetes, cancer, and heart failure. The number of patients suffering from musculoskeletal disorders is expected to increase in the future. However, intervention for muscle atrophy is limited, so research on treatment for muscle wasting is needed. This study hypothesized that guava leaf (Psidium guajava L. [GL]) would have ameliorative effects on muscle atrophy by regulation of protein degradation pathways in a dexamethasone (DEX)-induced muscle atrophy mice model. Muscle atrophy was induced by DEX injection for 28 days in 7 week-old-male ICR mice. Then, low-dose GL (LGL, 200 mg/kg) or high-dose GL (HGL, 500 mg/kg) extract (GLE) was supplemented by oral gavage for 21 days. Muscle strength, calf thickness, and body composition were analyzed. Histopathological changes in the gastrocnemius muscle were examined using hematoxylin and eosin staining, and molecular pathways related to muscle degradation were analyzed by western blots. GLE treatment regardless of dose increased muscle strength in mice with muscle atrophy accompanied by attenuating autophagy related pathway in the DEX-induced muscle atrophy mice. Moreover, a high dose of GLE treatment ameliorated ubiquitin proteasome system and apoptosis in the DEX-induced muscle atrophy mice. This study suggested that GLE could be helpful to improve muscle health and alleviate proteolysis by regulation of the ubiquitin-proteasome system, autophagy, and apoptosis, which are involved in muscle degradation. In conclusion, GLE could be a potential nutraceutical to prevent muscle atrophy.

Review on the Anti-Hyperglycemic Potential of Psidium guajava and Seriphium plumosum L.

The treatment and management of diabetes mellitus (DM) with conventional therapies, such as insulin injections and oral hypoglycemic agents, present significant challenges due to their side effects and burdensome administration. Therapies often manage symptoms rather than addressing insulin regulation, akin to medications like thiazolidinediones and glinides, which resemble many medicinal plants. Medicinal plants offer potential alternative treatments due to bioactive compounds targeting diabetes causes. We aimed to explore the antidiabetic potential of two medicinal plants, Psidium guajava and Seriphium plumosum L., by investigating their phytochemical constituents, medicinal uses, pharmacological actions, and mechanisms. This review followed specific guidelines and searched databases including PubMed, Scopus, ScienceDirect, and Web of Science for studies on medicinal plants and DM. Eligible studies underwent quality assessment and were categorized based on their design and interventions for data synthesis. This review identified the phytochemical constituents in Psidium guajava and Seriphium plumosum L., including tannins, flavonoids, phenols, and steroids, exerting antidiabetic effects through various mechanisms like antioxidant activity, anti-inflammatory effects, stimulation of insulin secretion, glucose regulation, and inhibition of carbohydrate-digesting enzymes. Psidium guajava and Seriphium plumosum L. exhibit promising antidiabetic potential, offering alternative approaches to diabetes management. Polyherbalism, combining multiple plant extracts, may enhance therapeutic efficacy in diabetes treatment. Comprehensive research is needed to explore the combined therapeutic effects of these plants and develop more effective antidiabetic treatments. This review highlights the importance of harnessing natural resources to combat the global burden of DM. Further research is warranted to fully explore the combined therapeutic effects of these plants and develop novel treatments.

Efficient removal of Sb(III) from wastewater using selenium nanoparticles synthesized by Psidium guajava plant extract.

Antimony (Sb) pollution in aquatic ecosystems has emerged as a critical environmental issue on a global scale, emphasizing the urgent need for cost-effective and user-friendly technologies to remove Sb compounds from water sources. In this study, a novel adsorbent, selenium nanoparticles (SeNPs), was synthesized using the aqueous extract of Psidium guajava L. leaves (AEP) for the purpose of eliminating Sb(III) from aqueous solutions. The biosynthesized SeNPs was characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray fluorescence spectrometer (XRF), Fourier Transform-Infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis techniques. Additionally, the removal efficiency of the SeNPs for Sb(III) was systematic investigated under the effects of SeNPs dose, temperature, pH and re-usability. The results of this study showed that the adsorption data fitted well into pseudo-second order model, while the Sips modeling demonstrated a high adsorption capacity (62.7 mg/g) of SeNPs for Sb(III) ions at 303.15 K from aqueous solution. The exothermic enthalpy change of - 22.59 kJ/mol and negative Gibbs free energy change assured the viability of the adsorption process under the considered temperature conditions. Surface functional groups on SeNPs like carboxyl, amide, hydroxyl, carbonyl, and methylene significantly facilitate the adsorption processes. Furthermore, the removal efficiencies of Sb in the two actual Sb mine wastewater samples were remarkably high, achieving nearly to 100% with 1.5 g/L SeNPs within 48 h. This outcome underscores the potential of SeNPs as a highly promising solution for efficiently remediating Sb from aquatic environments, owing to their cost-effectiveness, ease of regeneration, and rapid uptake capabilities.

Phytochemical Analysis of Silver Nanoparticles of Psidium guajava Leaf Extract and Evaluation for Its Antibacterial Property.

Nonessential heavy metals are toxic to human health. In this study, mercury, a hazardous metal, was detected by colorimetric analysis using Murraya koenigii. The eco-friendliness of this method was also emphasized. UV spectrum is a broad peak observed at 200-250 nm in P. guajava leaf extracts. The UV spectrum of green synthesized P. guajava exhibited an absorption band of 418 nm, which confirms the nanoparticle synthesis. FTIR analysis of the vibrational peak around 3307 cm-1 is assigned to ν(O-H) stretching that could possibly emanate from carbohydrates or phenolics. The peaks found around 2917 and 2849 cm-1 are ascribed to the -C-H stretch of the alkyl group, and the peak around 1625 cm-1 is due to the enolic ß-diketones or -C = O stretch of carboxylic acids, while the corresponding -C-O stretch is observed around 1375 and 1029 cm-1. The assignment of peaks is similar. It is clear from the SEM image that the constituent parts were non-uniform sphere-shaped, agglomerated, and of an average size of 30.9 nm. XRD analysis was utilized to determine the structural characteristics and crystalline nature of P. guajava. The observed intensity peaks at 32.35°, 36.69°, 39.24°, 44.76°, 59.42°, and 67.35° represent the 2θ values for P. guajava in the diffraction pattern, aligning with the values in the standard database. The synthesized AgNPs tested antibacterial properties against various strains of microorganisms, including Escherichia coli, 25 µg/mL 6.02 ± 0.17 and 100 µg/mL 7.3 ± 0.05, Staphylococcus aureus, 25 µg/mL 05.02 ± 0.07 and 100 µg/mL 11.3 ± 1.12, Streptococcus mutans, 25 µg/mL 04.02 ± 0.19 and 100 µg/mL 11.1 ± 0.11, Enterococcus faecalis, 25 µg/mL 0.8.05 ± 0.11 and 100 µg/mL 11.7 ± 0.02. The short novelty of Psidium guajava (guava) lies in its potential relevance to human health, as it has been found to possess bioactive compounds with various medicinal properties, such as antimicrobial, antioxidant, and anti-inflammatory activities, making it a promising natural resource for therapeutic applications.

Can Storage Stability and Simulated Gastrointestinal Behavior Change the Cytotoxic Effects of Concentrated Guava Leaves Extract against Human Lung Cancer Cells?

The influence of storage stability and simulated gastrointestinal behavior of different extracts of guava leaves extracts (NC: not concentrated, and C10 and C20: concentrated by nanofiltration) was evaluated based on their total phenolic compound (TPC) contents and antioxidant activity as well as on their cytotoxic effects on A549 and Vero cells. The results showed that C10 and C20 presented high stability for 125 days probably due to their high TPC contents and antioxidant activity. The simulated gastrointestinal behavior modified their TPC contents; however, after all digestion steps, the TPC values were higher than 70%, which means that they were still available to exert their bioactivities. Additionally, the cytotoxic effects of these extracts were evaluated before and after the simulated gastrointestinal behavior or under different storage conditions. C10 presented the best selectivity indices (SI) values (IC50 Vero cells/IC50 A549 cells) at both conditions suggesting that it can be considered a potential extract to be developed as a functional food due to its resistance to the gastrointestinal digestion and storage conditions tested.

Antidiarrheal effect of Psidium guajava L. extract in acute diarrhea: a systematic review.

Acute diarrheal diseases are a leading cause of childhood mortality and morbidity worldwide. Psidium guajava has been globally used for its antidiarrheal potential. We conducted a systematic review of scientific articles published up to the year 2021, which included in vivo pre-clinical tests and clinical trials involving patients with acute infectious diarrhea to verify the antidiarrheal, antibacterial and antispasmodic effects of galenic preparations or phytopharmaceuticals from P. guajava. PRISMA and Rayyan were used as tools for the selection of studies collected in four databases (Pubmed, Scopus, Web of Science and Science Direct). The keywords used to carry out the search were: 'Psidium guajava', 'guava', 'antidiarrhe*' and 'diarrhe*', joined by Boolean operators 'OR' or 'AND'. The characteristics of studies in animal models of acute diarrhea induction, as well as in vivo and in vitro motility and microbiological tests linked with its main pathophysiological mechanisms, were collected. Twenty-three articles were included. Twenty (87%) of these reported heterogenic preclinical studies, predominating pharmacological studies of efficacy against conventional antidiarrheal agents, which utilized relevant outcomes and models of infectious diarrhea from the top pathogens in the clinic along with classical castor oil-induced diarrhea associated with motility tests. Only three articles (13%) corresponded to clinical trials investigating the efficacy, dose and safety of these preparations. Most studies reported positive results and significant mechanistic evidence from antibacterial, anti-motility, anti-secretory and protective/anti-inflammatory perspectives. However, further studies are needed to define the clinical significance and safety treatment with P. guajava extracts. © 2024 Society of Chemical Industry.

Edible Medicinal Guava Fruit (Psidium guajava L.) Are a Source of Anti-Biofilm Compounds against Pseudomonas aeruginosa.

Psidium guajava is one of the most common edible medicinal plants frequently used in Malagasy traditional medicine to treat gastrointestinal infections. In order to evaluate their probable antibacterial activities, three organic extracts (successive extractions by hexane, dichloromethane, and ethanol) of ripe guava fruits were assessed for their bactericidal and anti-virulence properties against P. aeruginosa PAO1. Although these three extracts have shown no direct antibacterial activity (MIC of 1000 µg/mL) and, at the non-bactericidal concentration of 100 µg/mL, no impact on the production of major P. aeruginosa PAO1 virulence factors (pyocyanin and rhamnolipids), the hexane and dichloromethane extracts showed significant anti-biofilm properties and the dichloromethane extract disrupted the P. aeruginosa PAO1 swarming motility. Bioguided fractionation of the dichloromethane extract led to the isolation and identification of lycopene and ß-sitosterol-ß-D-glucoside as major anti-biofilm compounds. Interestingly, both compounds disrupt P. aeruginosa PAO1 biofilm formation and maintenance with IC50 of 1383 µM and 131 µM, respectively. More interestingly, both compounds displayed a synergistic effect with tobramycin with a two-fold increase in its effectiveness in killing biofilm-encapsulated P. aeruginosa PAO1. The present study validates the traditional uses of this edible medicinal plant, indicating the therapeutic effectiveness of guava fruits plausibly through the presence of these tri- and tetraterpenoids, which deserve to be tested against pathogens generally implicated in diarrhea.

Application of ionic liquid ultrasound-assisted extraction (IL-UAE) of lycopene from guava (Psidium guajava L.) by response surface methodology and artificial neural network-genetic algorithm.

Lycopene-rich guava (Psidium guajava L.) exhibits significant economic potential as a functional food ingredient, making it highly valuable for the pharmaceutical and agro-food industries. However, there is a need to enhance the extraction methods of lycopene to fully exploit its beneficial uses. In this study, we evaluated various ionic liquids to identify the most effective one for extracting lycopene from guava. Among thirteen ionic liquids with varying carbon chains or anions, 1-butyl-3-methylimidazolium chloride demonstrated the highest productivity. Subsequently, a single-factor experiment was employed to test the impact of several parameters on the efficiency of lycopene extraction using this selected ionic liquid. These parameters included extraction time, ultrasonic power, liquid-solid ratio, concentration of the ionic liquid, as well as material particle size. Moreover, models of artificial neural networks using genetic algorithms (ANN-GA) and response surface methodology (RSM) were employed to comprehensively assess the first four key parameters. The optimized conditions for ionic liquid ultrasound-assisted extraction (IL-UAE) were determined as follows: 33 min of extraction time, 225 W of ultrasonic power, 22 mL/g of liquid-solid ratio, 3.0 mol/L of IL concentration, and extraction cycles of three. Under these conditions, lycopene production reached an impressive yield of 9.35 ± 0.36 mg/g while offering advantages such as high efficiency, time savings, preservation benefits, and most importantly environmental friendliness.

First Report of Neofusicoccum parvum Causing Fruit Rot on Psidium guajava in China.

Guava (Psidium guajava L.), a nutrient-rich and economically significant fruit, is extensively cultivated in southern China. In six continuous years (from 2018 to 2023), dark-purple rotted guava with sunken lesion were observed on guava trees (variety 'Zhenzhu', aged over 5 years) in Dongguan and Panyu districts, Guangdong Province. Annually, the incidence of fruit rot disease in the affected fields reached 30% to 50% and significantly reduced the yield and quality of harvest guava. The initial symptoms on the epicarp of the fruits were black, needle-like dots that rapidly spread, causing partial or complete fruit rot within two to three weeks. To identify the causative agent, six symptomatic fruits were collected from two different orchards. Samples of 0.5 cm³ were excised from the lesion margins of each fruit. These samples were surface-sterilized with 70% ethanol for 30 seconds, followed by 0.2% NaClO for 2-3 minutes, and rinsed in sterile water three times. The samples were then cultured on potato dextrose agar (PDA) at 25°C for five days. This process yielded eight fungal isolates with similar morphological. Initially, the colonies were white with dense aerial mycelium becoming dark gray after 4 to 5 days. The mycelia were septate and branched. No spores were observed on PDA. To induce spore formation, the isolates were cultured on water agar for 20 days. This process led to the production of hyaline, aseptate, ellipsoid conidia, which were thin-walled, smooth-surfaced, and measured 3.7-5.1 × 1.6-2.2 µm (n = 100). Three isolates, including at least one from each orchard (Np1, Np2, Np3), were selected for further analysis. Genomic DNA was extracted using Axygen MAG-FRAG-I-50 (Axygen Bio-Tek). The internal transcribed spacer of rDNAs (ITS), beta-tubulin (tub2), the nuclear ribosomal large subunit (LSU), and translation elongation factor 1-α (tef1-α) gene regions were amplified using the primers ITS1/4, Bt2a/Bt2b, LR5/LR0R, and EF1-728F/EF1-986R (Golzar and Burgess 2011) and sequenced. Sequence analysis using MEGA 7.0 (Kumar et al., 2018) revealed 100% similarity among the isolates. BLAST searches of the ITS, tub2, LSU, and tef1-α sequences (accession nos. MN907637, MT537938, MT528156, MT537939) showed the highest nucleotide similarities (99.24 to 100%) to Neofusicoccum parvum strains (Crous et al. 2006). A phylogenetic tree was constructed with MEGA 7.0 based on the nucleotide sequence tub2 using the maximum likelihood method. Pathogenicity tests on 10 healthy guava fruits using mycelium-inoculated and control fruits confirmed the causative agent. The inoculated fruits, maintained at 25°C under a 12-h light/dark cycle, exhibited symptoms identical to the field infections within four to seven days, while control fruits remained symptomless. The fungus, reisolated from the inoculated fruits, was morphologically identical to the original isolates, fulfilling Koch's postulates. In conclusion, based on molecular, morphological, and pathogenic analysis, N. parvum as the causal agent of the fruit rot disease on guava. Previously, N. parvum has been reported in association with fruit rot on Eriobotrya japonica and Juglans regia (Zhai et al. 2019; Chen et al. 2019). To our knowledge, this is the first report of N. parvum affecting guava in China.

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.