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.

Nanoemulsion-Based Orodispersible Film Formulation of Guava Leaf Oil for Inhibition of Oral Cancer Cells.

Among natural sources, guava leaf oil (GLO) has emerged as a potential anticancer agent. However, its limited water solubility poses a significant challenge for its use. Oil-in-water nanoemulsions are used to address the limitation of water solubility of GLO prior to its incorporation into orodipersible films. Nanoemulsions containing GLO:virgin coconut oil (VCO) at a ratio of 50:50 to 70:30 presented a small droplet size of approximately 50 nm and a relatively low zeta potential. GLO:VCO at a ratio of 70:30 was selected for incorporation into sodium alginate film at various concentrations ranging from 1% to 30% w/w. Tensile strength and elongation at break relied on the concentration of nanoemulsions as well as the internal structure of films. Fourier transform infrared spectroscopy revealed that GLO was compatible with sodium alginate. Film containing 2% w/w of nanoemulsions (2G_ODF) exhibited effective in vitro antioral cancer activity, with an IC50 of 62.49 ± 6.22 mg/mL; furthermore, its anticancer activity showed no significant difference after storage at 25 °C for 1 year. Moreover, 2G_ODF at IC60 arrested colony formation and cell invasion. There is also evidence that cell death occurred via apoptosis, as indicated by nuclear fragmentation and positive Annexin-V staining. These findings highlight the potential of orodispersible films containing GLO nanoemulsions as a prospective oral anticancer agent.

Development of the paper-based colorimetric sensor for simple and fast determination of quercetin in guava leaf extract.

This present study aimed to develop a paper-based colorimetric sensor in the form of paper-microzone plates (PµZP), for simple and fast quercetin determination in guava leaf extract samples. Here, N-bromosuccinimide (NBS) solution was immobilized on the microzone as a sensing probe, where quercetin solution can be dropped on it to form red-purplish color adducts which can be seen by the naked eye or captured using a flatbed scanner. The color intensity of the microzone can be quantified against a blank solution and used as analytical data in scanometric assay. The sensor showed a response time of 8 min, a linear interval of 1-10 mM with a detection limit at 1.274 mM toward quercetin, and exhibited good reproducibility (RSD < 1%) and accuracy (98-99% recovery). The quercetin level of guava leaf extract determined by the PµZP-scanometric method was found comparable with that of the TLC-densitometric method, suggesting its use as an alternative method for quercetin analysis in the guava leaf extract.

Quality Attributes of Cold-Stored Khalal Barhi Dates Treated with Guava Leaf Extract and/or Lactic Acid as Natural Preservatives.

The use of natural ingredients to preserve the quality of fresh fruits is a promising approach to healthier products and a more sustainable industry. The present study was carried out to assess the effect of lactic acid (LA) and guava leaf extract (GLE) as natural preservatives on the quality parameters of Khalal Barhi dates. Physicochemical properties, antioxidant activity, color parameters, firmness, sensory properties, and yeast and mold counts of date fruits were evaluated during five weeks of storage at 4 ± 1 °C. The bioactive compounds in GLE were estimated by HPLC, which exhibited that GLE contains significant amounts of bioactive compounds, mainly, phenolics and flavonoids. With prolonged storage, the moisture content decreased, while the total soluble solids (TSS) increased in all samples. Similarly, a slight decrease in the pH with a concomitant increase in titratable acidity (TA) was observed throughout the storage. Generally, the samples treated with natural preservatives revealed lower changes in moisture content, TSS, pH, and TA than the control. The results exhibited decreased total phenolic content (TPC) and antioxidant activity for all samples with extended storage. The GLE and LA + GLE treatments significantly (p < 0.05) increased TPC and antioxidant activity on day 0 and preserved higher values of both during storage. Additionally, a decrease in the L* and b* values with an increase in the a* values of all samples was observed with advancement of storage. The LA + GLE treatment minimized the changes in color parameters and maintained higher firmness values during storage. Similarly, the sensory properties of all samples decreased with prolonged storage, but insignificant (p > 0.05) differences were found among the samples. Dipping treatments inhibited microbial growth over time, with the lowest yeast and mold counts achieved by the LA + GLE treatment. It can be concluded that the LA + GLE treatment has a protective effect on Khalal Barhi dates by minimizing post-harvest changes and decreasing the microbial load.

Antioxidant and Anti-Cytotoxicity Effect of Phenolic Extracts from Psidium guajava Linn. Leaves by Novel Assisted Extraction Techniques.

Phytochemicals (PCs) are gaining popularity due to their antioxidant effects and potential protection against infection, cardiovascular disease, and cellular metabolic activity. These PCs must be retained as much as possible during extraction. This research focused on the extraction of PC from Psidium guajava Linn. leaves due to higher antioxidant potential. Solvent extraction (SE), microwave-assisted extraction (MAE), and ultrasound-assisted extraction (UAE) using distilled water (DW) or 60% (v/v) ethanol/water (ET) were used for the extraction of PC. ET shows higher total phenolic (TPC) and total flavonoid content (TFC) as well as higher antioxidant activity than DW. Phytochemical screening demonstrated that all of the screening showed positive results in all extraction methods, except glycoside. There were no significant differences (p > 0.05) in TPC and TFC during MAE/ET, SE/ET, and UAE/ET. Antioxidant analysis shows that MAE and SE resulted in high (p < 0.05) DPPH and FRAP values for ET and DW, respectively. MAE/ET showed the highest inhibitory activity (IC50 = 16.67 µg/mL). HPLC and TLC analysis reveal the fingerprint of morin, which might function as an anticancer agent with other bioactives. Increasing the extract content increased the inhibitory activity of SW480 cells via MTT assay. In conclusion, MAE/ET is the most efficient among the extraction techniques in terms of anti-cytotoxicity effects.

Application of carboxymethyl chitosan-based coating in fresh-cut apple preservation: Incorporation of guava leaf flavonoids and their noncovalent interaction study.

Carboxymethyl chitosan (CMCS) has antibacterial activity and coating-forming ability. Under the impact of noncovalent interactions, the bioactivity and functionality of CMCS may be positively affected by the coexistence of flavonoids. This study investigated the effect of a CMCS coating incorporated with flavonoids from guava (Psidium guajava L. cv. Carmine) leaf (GLF) on the refrigeration of fresh-cut apples for preservation. Compared with the CMCS group, apples treated with the CMCS-GLF coating showed better quality (weight loss, browning index, firmness), nutritional value (ascorbic acid and total phenolic content), and microbial safety during storage. The mechanism study indicated that the hydrogen bonding, electrostatic, and hydrophobic interactions between CMCS and GLF (the carboxymethyl moiety of CMCS had the highest response priority and binding strength of the interaction with -C-O of GLF) changed the surface charge distribution and microstructure of CMCS, and increased its molecular weight, particle size, viscosity, and hydrophobicity. Thus, the CMCS-GLF coating exerted better bioactivities (antibacterial and antioxidant activity), and its film showed better mechanical and barrier properties. These results revealed that the noncovalent interaction with GLF could modify the physiochemical properties of CMCS, which was beneficial to improve its bioactivity and application value in fresh fruit preservation.

Analysis of inhibition of guava (Psidium guajava l.) leaf polyphenol on the protein oxidative aggregation of frozen chicken meatballs based on structural changes.

This study compared the effects of guava leaf polyphenol (GLP) on the aggregation and structural changes of myofibrillar proteins (MPs) from chicken meatballs, frozen for 6 months, with that of tea polyphenol (TP). The high antioxidation ability of 450 mg/L GLP was manifested by changes in 1, 1-diphenyl-2-picrylhydrazyl (DDPH), 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, and the ferric reducing antioxidant power (FRAP) in vitro. Compared with the control, the carbonyl, disulfide bond content, particle size, zeta potential and turbidity of sample with GLP decreased by 25.9 %, 17.7 %, 18.2 %, 11.4 % and 11.7 %, respectively, while the solubility of the sample, after freezing it for 6 months, increased by 14.8 %. Meanwhile, in sustaining the structural stability of MPs, the GLP-treated group exhibited better microstructure (scanning electron microscopy, SEM), lower free amino and sulfhydryl loss, higher α-helix structure and fluorescence intensity than the control. Our results showed that GLP significantly inhibited MP aggregation, and was superior to TP in terms of its particle size, solubility, and turbidity, sulfhydryl content (P < 0.05). Overall, it was demonstrated that GLP has the potential to inhibit protein aggregation and enhance structural stability during frozen storage.

Effect and mechanism of norfloxacin removal by guava leaf extract in the ZVI/H2O2 system.

To overcome the bottlenecks of the conventional zero-valent iron Fenton-like (ZVI/H2O2) process, such as low reagent utilization, low applicable pH, and iron sludge contamination, guava leaf extract (GLE) was used as a green promoter to enhance ZVI/H2O2 process in this study. Compared with the ZVI/H2O2 system, the removal rate and kobs of norfloxacin by the ZVI/H2O2/GLE system were increased by 33.76% and 2.19 times, respectively. The experimental investigation of the mechanism showed that the attack of reactive oxygen species was the main pathway for the removal of pollutants, and three types of reactive oxygen species (1O2, O2-,·OH) generations in the ZVI/H2O2/GLE system were effectively promoted by the introduction of GLE. The reactivity improvement was mainly due to the decrease of pH. At the same time, the chelation of iron ions by GLE promoted the Fe(III)/Fe(II) cycle on the catalyst surface was also a minor mechanism to improve the reactivity. This study provides a crucial reference for the practical application of guava leaf to promote the ZVI/H2O2 process in environmental pollution control.

Inhibitory Effect of Guava Leaf Polyphenols on Advanced Glycation End Products of Frozen Chicken Meatballs (-18 °C) and Its Mechanism Analysis.

The inhibitory effect of guava leaf polyphenols (GLP) on advanced glycation end products (AGEs) of frozen chicken meatballs (−18 °C) and its possible inhibitory mechanism was investigated. Compared with control samples after freezing for 6 months, acidic value (AV), lipid peroxides, thiobarbituric acid reactive substance (TBARS), A294, A420, glyoxal (GO), Nε-carboxymethyl-lysine (CML), pentosidine, and fluorescent AGEs of chicken meatballs with GLP decreased by 11.1%, 22.3%, 19.5%, 4.30%, 8.66%, 8.27%, 4.80%, 20.5%, and 7.68%, respectively; while free sulfhydryl groups the content increased by 4.90%. Meanwhile, there was no significant difference between meatballs with GLP and TP in AV, A294, GO, and CML (p > 0.05). Correlation analysis indicated that GO, CML, pentosidine, and fluorescent AGEs positively correlated with AV, TBARS, A294, and A420, while GO, CML, pentosidine, and fluorescent AGEs negatively correlated with free sulfhydryl groups. These results manifested GLP could inhibit AGEs formation by inhibiting lipid oxidation, protein oxidation, and Maillard reaction. The possible inhibitory mechanism of GLP on the AGEs included scavenging free radicals, capturing dicarbonyl compounds, forming polyphenol−protein compounds, and reducing the formation of glucose. Therefore, the work demonstrated that the addition of plant polyphenols may be a promising method to inhibit AGEs formation in food.

Aqueous Extract of Guava (Psidium guajava L.) Leaf Ameliorates Hyperglycemia by Promoting Hepatic Glycogen Synthesis and Modulating Gut Microbiota.

Type 2 diabetes mellitus (T2DM) is a major global health concern. Psidium guajava L. (guava) is widely used for food as well as a folk medicine. Previous studies have shown its anti-diabetic and anti-inflammatory properties. However, the underlying mechanisms remains to be elusive. In this study, we assessed the potential therapeutic effects of aqueous extract of guava leaves (GvAEx) on T2DM and explored their potential mechanisms in vivo and in vitro. GvAEx was gavage administered for 12 weeks in diabetic db/db mice. Our results have demonstrated that GvAEx significantly lowered fasting plasma glucose levels (p < 0.01) and improved glucose tolerance and insulin sensitivity (p < 0.01, p < 0.05, respectively). Additionally, GvAEx increased hepatic glycogen accumulation, glucose uptake and decreased the mRNA expression levels of gluconeogenic genes. Furthermore, GvAEx-treatment caused higher glucose transporter 2 (GLUT2) expression in the membrane in hepatocytes. Notably, for the first time, we have elaborated the possible mechanism of the hypoglycemic effect of GvAEx from the perspective of intestinal microbiota. GvAEx has significantly changed the composition of microbiota and increased short chain fatty acid (SCFA) -producing Lachnospiraceae family and Akkermansia genus in the gut. Taken together, GvAEx could alleviate hyperglycemia and insulin resistance of T2DM by regulating glucose metabolism in the liver and restoring the gut microbiota. Thus, GvAEx has the potential for drug development against T2DM.

Chemical Composition, Antibacterial, Antioxidant and Enzyme Inhibitory Activities of the Essential Oil from Leaves of Psidium guajava L.

Guava (Psidium guajava L.) leaf essential oil (GLEO) was extracted by water distillation, and its in vitro antioxidant, antidiabetic, and antibacterial properties were evaluated. Using GC/MS to determine the chemical components of GLEO, 27 constituents were identified, accounting for 74.90 % of the total oil content, among which L-caryophyllene (24.46 %), L-calamenene (10.82 %), (-)-globulol (10.69 %), and α-copaene (8.71 %) were the main components. Subsequently, the antioxidant activity of GLEO was determined by DPPH, ABTS, and ß-carotene bleaching tests. The half maximal inhibitory concentration of GLEO for three free radicals were IC50 =17.66±0.07 µg/mL, IC50 =19.28±0.03 µg/mL, and IC50 =3.17±0.01 µg/mL, respectively. Moreover, GLEO exhibited remarkable α-amylase (IC50 =13.99±0.34 µg/mL) and α-glucosidase (IC50 =5.50±1.02 µg/mL) inhibitory activities. It was effective against Streptomyces acidiscabies (MIC=1.25 µg/mL), Ralstonia solanacearum (MIC=5 µg/mL), and Erwinia carotovora subsp carotovora borgey (MIC=2.5 µg/mL), showing significant antibacterial properties. Based on the findings, given the high biological activity of GLEO, it is a biological preservative for food, medicine, and cosmetics and is valuable in natural therapy and crop disease management.

Guava (Psidium guajava) leaf extract enhances immunity, growth, and resistance against Vibrio parahaemolyticus in white shrimp Penaeus vannamei.

This study investigated the effects of guava leaf extract (GLE) on immune responses, growth performance, and resistance to Vibrio parahaemolyticus in white shrimp (Penaeus vannamei). To examine the effect of GLE on the immune response of white shrimps, they were treated with various concentrations of GLE on hemocyte (in vitro) and were orally administered (in vivo) feed containing various concentrations of 0, 1, 5, and 10 g kg-1 GLE (control, GLE1, GLE5, and GLE10, respectively) for 28 days. Furthermore, their growth performance was evaluated for 56 days. In a separate experiment, the shrimps were challenged with V. parahaemolyticus injection after 7 days of culture. In vitro experiments indicated that GLE is nontoxic and can activate immune response. In vivo experiments revealed that the GLE5 led to the highest total hemocyte count, phenoloxidase activity, phagocytic activity, and superoxide anion production and the highest upregulation of lipopolysaccharide, ß-1,3-glucan-binding protein, peroxinectin, lysozyme, crustin, penaeidin 2, penaeidin 3, clotting protein, superoxide dismutase, and glutathione peroxidase. Moreover, better growth performance was observed in the GLE groups, with GLE5 exhibiting the highest specific growth rate, weight gain, and feed conversion rate. In addition, GLE5 enhanced resistance to V. parahaemolyticus, with a survival rate of 72.27%. In conclusion, GLE was found to be effective in enhancing nonspecific immune response and growth performance and in reducing V. parahaemolyticus infection in white shrimp.

Effects of Guava (Psidium guajava L.) Leaf Extract on the Metabolomics of Serum and Feces in Weaned Piglets Challenged by Escherichia coli.

The effects of dietary supplementation with guava leaf extracts (GE) on intestinal barrier function and serum and fecal metabolome in weaned piglets challenged by enterotoxigenic Escherichia coli (ETEC) were investigated. In total, 50 weaned piglets (Duroc × Yorkshire × Landrace) from 25 pens (two piglets per pen) were randomly divided into five groups: BC (blank control), NC (negative control), S50 (supplemented with 50 mg kg-1 diet GE), S100 (100 mg kg-1 diet GE), and S200 (200 mg kg-1 diet GE), respectively. On day 4, all groups (except BC) were orally challenged with enterotoxigenic ETEC at a dose of 1.0 × 109 colony-forming units (CFUs). After treatment for 28 days, intestinal barrier function and parallel serum and fecal metabolomics analysis were carried out. Results suggested that dietary supplementation with GE (50-200 mg kg-1) increased protein expression of intestinal tight junction proteins (ZO-1, occludin, claudin-1) (p < 0.05) and Na+/H+ exchanger 3 (NHE3) (p < 0.05). Moreover, dietary supplementation with GE (50-200 mg kg-1) increased the level of tetrahydrofolic acid (THF) and reversed the higher level of nicotinamide-adenine dinucleotide phosphate (NADP) induced by ETEC in serum compared with the NC group (p < 0.05), and enhanced the antioxidant capacity of piglets. In addition, dietary addition with GE (100 mg kg-1) reversed the lower level of L-pipecolic acid induced by ETEC in feces compared with the NC group (p < 0.05) and decreased the oxidative stress of piglets. Collectively, dietary supplementation with GE exhibited a positive effect on improving intestinal barrier function. It can reprogram energy metabolism through similar or dissimilar metabolic pathways and finally enhance the antioxidant ability of piglets challenged by ETEC.

Extraction of bioactive compounds from Psidium guajava leaves and its utilization in preparation of jellies.

Psidium guajava L. (guava) is predominantly grown throughout the world and known for its medicinal properties in treating various diseases and disorders. The present work focuses on aqueous extraction of bioactive compounds from the guava leaf and its utilization in the formulation of jelly to improve the public health. The guava leaf extract has been used in the preparation of jelly with pectin (1.5 g), sugar (28 g) and lemon juice (2 mL). The prepared guava leaf extract jelly (GJ) and the control jelly (CJ, without extract) were subjected to proximate, nutritional and textural analyses besides determination of antioxidant and antimicrobial activities. GJ was found to contain carbohydrate (45.78 g/100 g), protein (3.0 g/100 g), vitamin C (6.15 mg/100 g), vitamin B3 (2.90 mg/100 g) and energy (120.6 kcal). Further, the texture analysis of CJ and GJ indicated that both the jellies showed similar properties emphasizing that the addition of guava leaf extract does not bring any change in the texture properties of jelly. GJ exhibited antimicrobial activity against various bacteria ranging from 11.4 to 13.6 mm. Similarly, GJ showed antioxidant activity of 42.38% against DPPH radical and 33.45% against hydroxyl radical. Mass spectroscopic analysis of aqueous extract confirmed the presence of esculin, quercetin, gallocatechin, 3-sinapoylquinic acid, gallic acid, citric acid and ellagic acid which are responsible for antioxidant and antimicrobial properties.

Ethanolic guava leaf extracts with different chlorophyll removal processes: Anti-melanosis, antibacterial properties and the impact on qualities of Pacific white shrimp during refrigerated storage.

Ethanolic guava leaf extract (EGLE) without chlorophyll removal (GLE-C) and those with chlorophyll removal using sedimentation process (GLE-S) or dechlorophyllization using chloroform (GLE-Ch) were prepared. Antibacterial and anti-melanosis properties of all extracts were examined. All extracts showed promising antibacterial properties, polyphenoloxidase inhibitory activity and copper chelating activity. These activities were highest in GLE-S (P < 0.05). Piceatannol 4'-galloylglucoside, epicatechin, 8-hydroxyluteolin 8-sulfate, quercetin 3-(2''-galloyl-alpha-l-arabinopyranoside), and aclurin 3-C-(6''-p-hydroxybenzoyl-glucoside) were dominant in GLE-S. When Pacific white shrimp were treated with GLE-S at different concentrations (0.5 and 1%), the quality changes were monitored compared to those treated with 1.25% sodium metabisulphite (SMS-1.25) and the control (without any treatment) during 12 days of storage at 4 °C. Changes in microbial and chemical qualities were lower in shrimps treated with GLE-S solution as compared to others. Therefore, melanosis and quality deterioration were effectively reduced by pretreating shrimps in GLE-S before refrigerated storage.

Effectiveness of the guava leaf extracts against lipopolysaccharide-induced oxidative stress and immune responses in Cyprinus carpio.

The anti-inflammatory activity of the guava leaf extracts (GLE) against LPS-induced inflammatory responses in fish macrophage cell lines is well documented. Here, we evaluated the effects of dietary GLE on LPS-induced oxidative stress, immune responses, and glucocorticoid receptor-related gene expression in Cyprinus carpio. Basal diet was supplemented with 0 (control), 100, 150, 200, or 250 mg kg-1 GLE for eight weeks. Highest (p < 0.05) weight gain rate was obtained in fish group supplemented with 200 mg kg-1 of GLE. The results showed that superoxide dismutase, glutathione-S-transferase, glutathione peroxidase, glutathione reductase, lysozyme, and complement C3 decreased, while malondialdehyde level increased in the liver and spleen upon LPS-challenge. Dietary GLE supplementation (especially 200 or 250 mg kg-1) alleviated LPS-induced changes. Similarly, GLE (150-250 mg kg-1) reversed LPS-induced alteration of serum biochemical parameters such as alkaline phosphatase, aspartate transaminase, alanine transaminase, and myeloperoxidase. LPS treatment markedly induced increased the mRNA levels of TNF-α, IL-1ß, and NF-κB p65 in both the liver and kidney tissues; however, GLE pre-treatment attenuated LPS-induced elicitation of TNF-α, IL-ß, and NF-κB p65. Moreover, dietary GLE supplementation significantly increased the expression of HSP70 and HSP90, and glucocorticoid receptor in the liver and kidney after LPS challenge. Thus, GLE attenuated LPS-induced inflammation response by up-regulating glucocorticoid receptor-related gene expression in carp. Finally, GLE supplementation reduced carp mortality after LPS-challenge. These results suggest that dietary supplementation with 200 mg kg-1 GLE is adequate for effectively attenuating LPS-induced oxidative stress and immune-suppressive effects in C. carpio.

A randomized open label efficacy clinical trial of oral guava leaf decoction in patients with acute infectious diarrhoea.

BACKGROUND: Diarrhoea is amongst the first ten causes of death and its treatment faces an increased threat of drug resistance. Previous studies on the guava leaf decoction (GLD) revealed its suitability for use in infectious diarrhoea of unknown etiology. OBJECTIVE: The objective of this trial was to establish efficacy, dose and safety of GLD prepared from the Indian Sardar variety in adults with acute infectious diarrhoea. METHODS: The current trial was an open efficacy randomized 5-day, parallel group multi-arm interventional study. Amongst 137 adults (18-60 years) suffering with acute diarrhoea, 109 were included (57% females, 43% males). Three doses of GLD (6-leaf, 10-leaf and 14-leaf) were compared with controls receiving oral rehydration solution. Decrease in stool frequency and improvement in consistency were the outcomes measured. The data was analyzed using ANOVA, Tukey's post-hoc test, Kruscal-Wallis test and Chi-Square test where applicable. RESULTS: The trial showed that the 14-leaf (7.4 g) decoction was the most effective. Administration of the decoction, thrice daily helped the patients regain normalcy in 72 h as opposed to 120 h in controls. Safety of the intervention was reflected by normal levels of haemoglobin, liver and kidney parameters. No adverse events were reported. CONCLUSION: The 14 leaves decoction was a safe treatment for adult acute uncomplicated diarrhoea of unknown etiology. Moreover due to component synergy and divergent mechanisms of action, it could possibly combat the generation of drug resistance and destruction of gut microbiota. Hence GLD has the potential for development as a first line treatment for diarrhoea. TRIAL REGISTRATION: Trial was registered with Clinical Trials Registry - India (CTRI registration number: CTRI/2016/07/007095). The trial was retrospectively registered.

Guava leaves extract ameliorates STZ induced diabetes mellitus via activation of PI3K/AKT signaling in skeletal muscle of rats.

Blood glucose homeostasis and insulin signaling pathway regulation take a vital role in the management of diabetes mellitus. Our present was designed to explore the mechanism of the blood homeostasis, regulation of oxidative stress and insulin signaling pathway by guava leaf extract (GLE). Diabetes mellitus was induced in male albino Wistar by streptozotocin (STZ) (Single dose-40 mg/kg b.w.). As an extension STZ rats received GLE (GLE; 200 mg/kg b.w). At the end of the study the lipid peroxidation products, antioxidants, insulin signaling genes were analyzed. Treatment with GLE resulted in decreased plasma and skeletal muscle lipid peroxidation markers, increased antioxidants, and improved insulin signaling genes. GLE treatment helps to maintain blood homeostasis alleviates oxidative stress and regulates the insulin signaling genes in skeletal muscle. Overall the results suggest GLE treatment regulates blood glucose, inhibits oxidative stress, and importantly it regulates insulin signaling pathway genes in skeletal muscle. Further studies on the GLE role in other important pathways can add additional strength to the claim that GLE is a strong anti-diabetic candidate.

Guava Leaf Extract Attenuates Insulin Resistance via the PI3K/Akt Signaling Pathway in a Type 2 Diabetic Mouse Model.

BACKGROUND AND OBJECTIVE: Insulin resistance is well known to exhibit essential effects on the progression of diabetes mellitus (DM). Guava leaf was also reported to exhibit anti-diabetic effects including decreasing blood glucose. Therefore, this present study aims to explore the role guava leaf extract (GLE) plays in insulin resistance and its mechanism of action via the PI3K/Akt signaling pathway. METHODS: KK-Ay mice is a spontaneous genetic type 2 diabetes mouse model induced by feeding a high fat and high sugar diet. Mice were randomly assigned into three groups: diabetic mice (DM), DM + MET (diabetic mice treated with metformin) and DM + GLE (diabetic mice treated with GLE) groups. After 8 weeks of treatment, body weight and levels of fasting plasma glucose (FPG), fasting insulin and lipids in plasma were measured. Mice were sacrificed and mRNA and protein expression of insulin receptor substrate1 (IRS1), phosphatidylinositol 3-kinase (PI3K) and serine/threonine kinase protein B (Akt) in livers were measured. RESULTS: GLE markedly reduced body weight, FPG, fasting insulin and insulin resistance index but increased the insulin sensitivity index of diabetic KK-Ay mice. Moreover, GLE upregulated the expression of IRS-1, PI3K and Akt mRNAs in livers of diabetic KK-Ay mice. In addition, GLE also elevated IRS-1, PI3K, Akt, p-PI3K and p-Akt protein expression in their livers. The results of the DM + MET group were similar to those of the DM + GLE group. CONCLUSION: GLE plays anti-diabetic roles by ameliorating insulin resistance in KK-Ay diabetic mice and this is related to the activation of PI3K/Akt signaling pathway.

Application of natural antioxidant extract from guava leaves (Psidium guajava L.) in fresh pork sausage.

The current study was conducted to determine the antioxidant efficacy of guava leaf extract (3000 to 6000 ppm on fat basis) in fresh pork sausage, compared with negative control (CON) and 200 ppm butylated hydroxytoluene (BHT), for 0, 1, 4, 7, 10, and 14 d at 4 °C. The extract provided a total antioxidant capacity of 1505 µmol trolox equivalence/g. From d 4, the extract at 5000 and 6000 ppm provided greater (P < .05) antioxidant capacity than the CON and was either similar (P > .05) or greater (P < .05) than BHT. From d 4, the sausage formulated with 4000 to 6000 ppm of guava leaf extract had less conjugated dienes, lower peroxide and acidic values, less thiobarbituric reactive substances value, and better color (P < .05) than the CON and did not differ from BHT (P > .05). Guava leaf extract at 4000 ppm or greater is effective in preventing oxidation in fresh pork sausage.