Guajava Leaf Extract Research Articles

Evaluation of Antifungal Activity of Psidium guajava (Guava) Leaf Extracts

Aims: This study aimed to evaluate the effectiveness of four Psidium guajava leaf extracts against three strains of Candida albicans and a strain of Cryptococcus neoformans. Study Design: Experiment-observational study. Place and Duration of Study: P. guajava leaves were collected from specific areas in Regions Three and Four in Guyana; and the preparation of the leaf extracts and the treatment against the fungi were performed in two laboratories at the University of Guyana from August 2022-September 2023. Methodology: P. guajava leaves were washed with water, air-dried at room temperature, and ground in a disinfected food mixer. Extracts were prepared by soaking the ground leaves in different solvents, and then using the rotary evaporator to reduce the solutions and obtain crude extracts. Filter paper discs were prepared and allowed to soak in various concentrations of the crude extracts. The discs were then subjected to antifungal susceptibility testing on Potato Dextrose agar seeded with an appropriate fungus according to Clinical Laboratory Standards Institutes guidelines. The plates were incubated and the zone of inhibition (ZOIs) was measured. Results: P. guajava leaves were effective against all four strains of fungi evaluated. The largest ZOI was observed for C. neoformans (25 mm) with the ethyl acetate extract at 100 mg/mL concentration. Large ZOI was also observed for the three strains of C. albicans (10-15 mm). For one of the C. albicans strains, a ZOI significantly higher than the antifungal agents (ketoconazole and fluconazole) was observed with the P. guajava ethyl acetate extract at 100 mg/mL. Conclusion: It can be concluded that P. guajava leaves have antifungal activity against C. albicans and C. neoformans, potentially greater than current antifungal agents like ketoconazole and fluconazole.

Characterization of Copper Nanoparticles synthesized Using the Leaf Extracts of Lawsonia inermis, Eucalyptus globulus, Psidium guajava, and Azadirachta indica

Green synthesis of nanoparticles using plant extracts is a sustainable, eco-friendly, non-toxic, and cost-efficient approach. In this study, copper nanoparticles (CuNPs) were synthesized using the mehandi Lawsonia inermis, nilgiri Eucalyptus globulus, guava Psidium guajava, or neem Azadirachta indica leaf extracts and 1mM CuSO4.5H2O salt solution in a ratio of 1:3 at 800C temperature and characterized using UV-Visible spectroscopy, Fourier Transform Infrared spectroscopy, and Field Emission Scanning Electron Microscopy analysis. All the CuNPs showed colour change with characteristic surface plasmon resonance bands. The plasmon resonance bands of L. inermis, P. guajava, and A. indica CuNPs peaked at 300nm while those of E. globulus CuNPs peaked at 400nm. The CuNPs synthesized from L. inermis, E. globulus, and P. guajava leaf extracts exhibited brown colour while those synthesized from A. indica leaf extracts showed green colour. Eleven bands were present in L. inermis and A. indica CuNPs in the range of 538.61-3649.06cm-1 and 3867.26-519.02cm-1, respectively, while ten were in the E. globulus and P. guajava CuNPs in the range of 407.25-3326.78cm-1 and 3325.93-407.07cm-1, respectively. The L. inermis, E. globulus, and A. indica CuNPs were spherical, except P. guajava CuNPs which were flaky in shape. The particle size of L. inermis CuNPs was found in the range of 8.20 to 15.94nm; E. globulus CuNPs in the range of 7.52 to 67.47nm; P. guajava CuNPs in the range of 18.90 to 73.80nm and A. indica CuNPs in the range of 9.86 to 22.05nm.

Green synthesis of N-doped-carbon dots/ZnO for enhanced photocatalytic degradation of methylene blue dye: optimization of reaction parameters.

In this research work, nitrogen-doped carbon dots (N-CDs) adorned zinc oxide nanoparticles (N-CDs/ZnO) were successfully synthesized by a simple and cost-effective solution dispersion method and later on used as photocatalyst for decontamination of aqueous methylene blue (MB) dye on irradiation of UV light (300 W, 320-400nm) at room temperature. Both the N-CDs and ZnO were prepared through green technique utilizing non-toxic, inexpensive and eco-friendly precursors, namely Foeniculum vulgare and Psidium guajava leaf extract, respectively. All the synthesized samples exhibited crystalline nature with average diameter of particle 4.42nm, 12.38nm and 14.11nm corresponding to N-CDs, ZnO and N-CDs/ZnO, respectively. Further, band gap energy value (Eg) of 3.43, 2.76 and 2.49eV for N-CDs, ZnO and N-CDs/ZnO, respectively, were obtained by using Tauc's plot. The photocatalytic capability of the sample N-CDs/ZnO was compared with bare ZnO nanoparticles, utilizing identical experimental conditions. The results demonstrated that the composite exhibited notably higher photocatalytic degradation efficiency than bare ZnO nanoparticles up to 15.54%. Lower band gap value of N-CDs/ZnO was the major factor for exhibiting this behaviour, decreasing the recombination rate and thus enhancing the efficiency. Furthermore, N-CDs/ZnO exhibited 98.17% MB degradation under optimized conditions (0.03g, 5ppm, pH 10). The resultant N-CDs/ZnO exhibited good stability and decontamination efficiency up to five cycles with efficiency loss of only 7.89%. Along with, trapping experiments was conducted to analyze the role of active species involved for deep understanding of mechanism. The order of efficiency of active constituents was observed to be: •O2- > h+ > •OH. The study analyzed the non-toxic nature of treated water, revealing normal plant growth, suggesting its potential use in irrigation of parks and roadside areas. Overall, present research work obeys the green chemistry principles with the fabrication of highly efficient, eco-friendly, cost-effective photocatalyst N-CDs/ZnO by utilizing the green precursors for the whole research work.

Green Synthesis of Zinc and Iron Nanoparticles Using Psidium guajava Leaf Extract Stimulates Cowpea Growth, Yield, and Tolerance to Saline Water Irrigation

Plants use a variety of physiological, biochemical, and molecular mechanisms to mitigate salt stress impacts. Many techniques, including the application of nanoparticles (NPs), are being used to increase plant stress tolerance. To assess the growth and productivity of Vigna unguiculata L. (cowpea) plants exposed to salt stress, cowpea has been cultivated using different saline water levels and subjected to green synthesized zinc NPs (ZnNPs) and iron NPs (FeNPs) applied via foliar spraying. The cowpea plants that grew under the lowest saline water level showed the best leaf traits, leaf water content per area (LWCA), pods, and seed yields, but when salinity levels increased, the plants’ growth and productivity slightly declined. ZnNP and FeNP treatments slow down the degradation of photosynthetic pigments and greatly mitigate the negative effects of salt stress. In both stressed and unstressed plants, ZnNP treatments produced the highest osmoprotectant concentrations (proline, protein, and total carbohydrates). As a result of salt stress, cowpea seeds showed a marked decrease in dry matter and protein content, but ZnNP and FeNP treatments increased it. Conclusively, the results obtained indicated that ZnNPs and FeNPs foliar application to cowpea plants stimulated leaf pigment and polyphenol production, which in turn increased seed dry matter, seed yield, protein content, and the plants’ ability to withstand saline stress.

Structural, optical, antibacterial, antifungal, and anticancer activity of sodium alginate-pluronic-F127-tin dioxide nanoparticles prepared via microwave-assisted green process

The green synthesis of inorganic metal oxide nanoparticles is essential because it reduces environmental impact and enhances biocompatibility by using eco-friendly materials and processes. This sustainable approach also minimizes hazardous chemicals, promoting safer and cleaner production methods. The sodium alginate-Pluronic F127-modified SnO2 (SAPFSO) NPs were prepared using the green method using Psidium guajava leaf extract. The SAPFSO NPs exhibit a tetragonal rutile structure from the X-ray diffraction patterns. The FESEM and EDAX spectra identified the morphology and chemical composition. The Sodium Alginate, Pluronic-F127, and SnO2 functional group vibrations can be seen in the FTIR spectra. The DLS spectra and hydrodynamic sizes of SAPFSO NPs were observed at 183 nm. The various surface defects of SAPFSO NPs were identified from the PL spectrum. The antimicrobial activity of SAPFSO NPs was tested against gram-positive and gram-negative strains such as S. aureus, K. pneumoniae, S. dysenteriae, S. pneumoniae, Bacillus megaterium, Proteus valgaris, and Candida albicans fungal strain using the well-diffusion method. To increase the concentration, SAPFSO NPs also increased the antimicrobial activity. The anticancer activity of SAPFSO NPs tested against the human breast cancer cell line (MDA-MB-237). SAPFSO NPs exhibits potential anticancer activity against triple negative breast cancer cell line. These results support that SAPFSO NPs can be applied in healthcare and industrial settings to improve human health.

In-vitro antimicrobial efficacy of Psidium guajava leaf extracts against Escherichia coli and Staphylococcus aureus isolated from buffaloes suffering from subclinical mastitis

In-vitro antimicrobial efficacy of Psidium guajava leaf extracts against Escherichia coli and Staphylococcus aureus isolated from buffaloes suffering from subclinical mastitis

Fabrication of cellulose-based antimicrobial films integrated with in situ synthesized silver nanoparticles using Psidium guajava leaf extract

Cellulose-based antibacterial nanocomposite films were prepared by adding silver nanoparticles (AgNPs) synthesized in situ using a guava leaf extract. The nanocomposite films were synthesized using the solution casting method and characterized by analytical methods. The FTIR analysis indicated the presence of the carbonyl groups of guava leaf extract and hydroxyl groups of cellulose in the in situ synthesized AgNPs. The XRD analysis confirmed the AgNPs in the nanocomposites. SEM analysis revealed the presence of spherical AgNPs in the size range of 60-90 nm. The addition of AgNPs increased the tensile strength and thermal stability of composites. In addition, the cellulose-based nanocomposite film wasn’t showed very significant antibacterial activity against various foodborne pathogenic bacteria. Therefore, the prepared cellulose/AgNPs nanocomposite film is eco-friendly and exhibits excellent tensile strength and thermal stability along with a wide range of antimicrobial activity, so it is considered to be suitable for biomedical and food packaging applications.

Biogenic synthesis of Psidium guajava‐mediated silver nanoparticles: A comprehensive antibiofilm and antivirulence study

AbstractIn this study, at sub‐MIC, the efficacy of green synthesized Psidium guajava‐mediated silver nanoparticles (Pg@AgNPs) in inhibiting quorum sensing facilitated virulence factors and suppressing biofilm formation was evaluated against clinical multidrug resistant (MDR) isolates, specifically Chromobacterium violaceum MCC‐2290 and Pseudomonas aeruginosa PAO1. The AgNPs were synthesized by adding the leaf extract to a solution of silver nitrate, and the reduction of Ag+ ions to Ag0 was confirmed by the appearance of brown color. The Pg@AgNPs were characterized using Fourier transform infrared (FTIR), UV/Vis spectroscopy, TEM, and XRD. The UV/Vis spectrum showed the characteristic absorption peak of Pg@AgNPs in the range of 350–480 nm. FTIR analysis substantiated the existence of functional groups implicated in the synthesis and stabilization of AgNPs. The XRD analysis elucidated the crystalline characteristics of the nanoparticles. The TEM images further confirmed the spherical shape and size of the nanoparticles, which ranged between 5 and 25 nm. The AgNPs demonstrated notable antibacterial efficacy against C. violaceum and P. aeruginosa. Moreover, the Pg@AgNPs effectively suppressed both biofilm formation and the production of quorum sensing‐mediated virulence factors such as pyoverdin (77.2%), pyocyanin (78.12%), and violacein (83.4%). Additionally, the Pg@AgNPs demonstrated broad‐spectrum activity against biofilm formation, showing the biofilm inhibition in C. violaceum and P. aeruginosa by 81.86% and 87.89%, respectively. Under light microscopy, it is also observed that Pg@AgNPs reduce the formation of biofilm in both tested bacteria. The present finding highlights the potential of green‐synthesized AgNPs using P. guajava leaf extract as antimicrobial agents with potential applications in combating bacterial infections and biofilm‐related diseases.

LENGTH-WEIGHT RELATIONSHIP OF CLARIAS GARIEPINUS FED PSIDIUM GUAJAVA AND MANGIFERA INDICA LEAF EXTRACT

The length weight relationship (LWR) of Clarias gariepinus fed Psidium guajava and Mangifera indica leaf extract was evaluated for six (6) months. A total of 420, eight (8) weeks old fingerlings of Clarias gariepinus was used for this study. Experimental fish were fed 40 % crude protein diet with inclusion of both leaf extracts at 0 %, 4 %, 6 %, and 8 %. Experimental fish were stocked in twenty-one 4ft by 4ft tarpaulin tanks half filled with borehole water, acclimation was done for 7 days during which they were fed commercial diet. Aqueous extract was done for both leaves and stored in plastic cans for further use. Weight and length of fish was measured biweekly and data was used to assess the length-weight relationship. The result of this study showed that the best weight was recorded in treatment 2 fed 4 % Psidium guajava extract and the least in treatment 5 fed 4 % Mangifera indica extract. The result on LWR revealed the regression coefficient ‘b’ to be from 17.68-20.40 which indicates a positive allometric growth, since ‘b’ value is more than 3. This further means that the fish samples in this study became heavier, stouter, deeper bodied or bigger as it increases in length i.e all parts of the fish increase in size proportionately with the length.

Psidium guajava-mediated green synthesis of Fe-doped ZnO and Co-doped ZnO nanoparticles: a comprehensive study on characterization and biological applications.

The efficacy of nanoparticles (NPs) in healthcare applications hinges on their biocidal activity and biocompatibility. This research is dedicated to green-synthesized NPs with potent biocidal properties, aiming for high inhibition rates in bacterial infections and offering a multifunctional application, including potential use in anticancer therapy, in comparison to traditional antibiotics. The present study focuses on synthesis of zinc oxide (ZnO) nanoparticles (NPs), including iron-doped ZnO (GZF) and cobalt-doped ZnO (GZC), using the green co-precipitation method involving Psidium guajava (P. guajava) leaf extract. The physicochemical properties of the synthesized NPs were analyzed using various characterization techniques. The antibacterial and anticancer activity depends on the generation of reactive oxygen species (ROS), particle size, surface area, oxygen vacancy, Zn2+ release, and diffusion ability. The antibacterial activity of the synthesized NPs was tested against various Gram-positive (Streptococcus pneumoniae (S. pneumoniae), Bacillus subtilis (B. subtilis) and Gram-negative (Klebsiella pneumoniae (K. pneumoniae), and Pseudomonas aeruginosa (P. aeruginosa) bacterial strains. The zone of inhibition showed higher activity of GZC (18-20mm) compared to GZF (16-19mm) and GZO (11-15mm) NPs. Moreover, anticancer studies against blood cancer cell line (MOLT-4) showed half-maximal inhibitory concentration of 11.3μg/mL for GZC compared to GZF and GZO NPs with 12.1μg/mL and 12.5μg/mL, respectively. Cytotoxicity assessments carried out on the fibroblast L929 cell line indicated that GZO, GZF, and GZC NPs demonstrated cell viabilities of 85.43%, 86.66%, and 88.14%, respectively. Thus, green-synthesized GZC NPs hold promise as multifunctional agents in the biomedical sector.

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 β-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.

Study on Chemical Composition and Biological Activity of Psidium guajava Leaf Extracts.

Guava (Psidium guajava) is a plant widely distributed in tropical and subtropical regions. Its leaves contain a large amount of physiological molecules such as flavonoid, sesquiterpene, triterpenoid, coumarin, alkaloid, and tannin molecules with antioxidative and anti-inflammatory effects. In this study, the use of concentrated P. guajava leaf extract molecules as a functional natural material was evaluated by confirming the extract's antioxidative, antibacterial, tyrosinase activity inhibition, and collagenase activity inhibition effects and its trans-2-nonenal removal ability. As a result of the analysis of the antioxidant and antibacterial components of concentrated P. guajava leaf extract molecules through GC-MS, a large amount of aromatic hydrocarbon molecules were detected. When different concentrations of ethanol were used for extraction, the leaf extract concentrated with 70% ethanol showed the most effective active molecules. As a result of measuring DPPH radical scavenging activity, a concentration-dependent antioxidant activity was confirmed. The antioxidant activity tended to increase when the ethanol content used for extraction was increased. Molecules such as 2,4-di-tert-butylphenol, caryophyllene oxide, and γ-muurolene in P. guajava leaf extract concentrate appeared to have antibacterial activities against S. aureus bacteria known to cause atopy. As ethanol content increased, the inhibitory effect on tyrosinase activity was increased. In addition, when ethanol content was 50%, the concentrated leaf extract was able to remove trans-2-nonenal by 52.4%. As a result of determining the concentrated leaf extract's collagenase inhibition activity, an inhibition rate close to that of ascorbic acid, a positive control, was confirmed. The concentrated guajava leaf extract molecules were confirmed to have whitening and wrinkle-improving functionality. Thus, the P. guajava leaf extract has high potential as a food and natural cosmetic material.

Bio‐Synthesis of Silver Nanoparticles Decorated on Hydrotalcite using Psidium Guajava Leaf Extract and Its Anti‐Bacterial Effect

AbstractPhenolic compounds are widely known for its well‐reduced behavior and surprisingly appeared in many leaf extracts, including Psidium guajava (P. guajava) leaf. This leaf extract has been confirmed as an efficiency reducing agent to reduce Ag(I) ions to silver nanoparticles (AgNPs). This work focused on the development of a “green” synthesis of nanosilver‐hydrotalcite nanoparticles (HT‐AgNPs) based on the bio‐reduction of the P. guajava leaf extract and the application of HT‐AgNPs as an antibacterial material. To assess factors affecting on synthesis process of the HT‐AgNPs, experiments have been carried out with a fixation of HT/AgNO3 precursors while varying concentration of P. guajava leaf extract as well as solvent for the extraction. The methods, including ultraviolet‐visible (UV‐Vis) spectroscopy, infrared (IR) spectroscopy, field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS), X‐ray diffraction (XRD) and energy dispersive X‐Ray (EDX), transmission electron microscopy (TEM) have been used to characterize the HT‐AgNPs. The yield of reduction process of Ag(I) ions to AgNPs on HT reached 55.12 to 90.55 % depending on the content of AgNO3 precursor. In particular, the antibacterial activity of HT‐AgNPs against to E. coli and S. aureus was also assessed and discussed.

Synthesis, characterization, and antibacterial study of chitosan-zinc oxide nanocomposite-coated superhydrophobic cotton fabric.

Awareness of microbial infection, hygiene, and personal health has increased in recent years, particularly in light of the pervasive pandemic encountered by the global community. This has prompted the development of antibacterial and superhydrophobic cotton fabric to address the pressing challenge. In this investigation, we report bio-mediated zinc oxide nanoparticles (ZnO NPs) synthesized using Psidium guajava leaf extract and zinc acetate. Further, the chitosan-ZnO nanocomposite (CS-ZnO) was synthesized and subsequently deposited on cotton fabric (CF) via a facile and cost-effective pad-dry-cure method to produce CS-ZnO-CF. The ZnO NPs, CS-ZnO, and CS-ZnO CF were characterized using FTIR, XRD, SEM-EDAX, TGA and AFM analysis. Additionally, we investigated the mechanical properties and water contact angle (WCA) of uncoated cotton (UCF) and CS-ZnO CF. The CS-ZnO-CF demonstrated good mechanical stability even after 50 abrasion cycles, good washing durability, and good super-hydrophobicity, with a high WCA (153.1°). The antibacterial study indicated that CS-ZnO and CS-ZnO-CF exhibited higher antibacterial activity than UCF against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria. This study introduces a simple, environmentally friendly, and economically scalable method for producing multifunctional CS-ZnO CF, showcasing its potential for diverse applications.

Formulation and evaluation of Psidium guajava leaf extract microparticles

Formulation and evaluation of Psidium guajava leaf extract microparticles

Antibacteria Activities of Guava (Psidium guajava) and Orange (Citrus sinensis) Leaves Extracts on Staphylococcus aureus and Escherichia coli

his study aimed at determining the antibacterial activities of Psidium guajava and Citrus sinensis leaves extracts of aqueous, ethanol, and methanol on Staphylococcus aureus and Escherichia coli. Dimethyl sulfoxide was used for dissolving the leaves extracts and the minimum inhibitory concentration (MIC) of the extracts was determined using broth dilution technique to observe their antibacterial activities against S. aureus and E. coli. The phytochemical screening revealed the presence of metabolites (flavonoids, tannins, steroid saponins, saponins and alkaloids). The inhibition zone of the aqueous, ethanol and methanol extracts of P. guajava and C. sinensis against Staphylococcus aureus and Escherichia coli was highest at 200mg/ml (18mm and 17mm), while the least inhibition zone was at 12.5mg/ml (7mm and 0mm) respectively. The aqueous extracts of P. guajava and C. sinensis against E. coli and S. aureus had its MIC at 50g/ml and 100mg/ml respectively, while ethanol extracts of P. guajava and C. sinensis against the bacterial (E. coli and S. aureus) had its MIC at 50g/ml. The methanol extracts of P. guajava and C. sinensis showed the growth of S. aureus in all concentrations (12.5g/ml, 25g/ml, 50g/ml, 100mg/ml and 200mg/ml) while E. coli had no growth from 100mg/ml above concentrations and 50g/ml (MIC) of P. guajava leaf extracts. These findings, therefore support the traditional use of Psidium guajava and Citrus sinensis for its curative potential to synthetic drugs which are expensive, not easily accessible with potential side effects.

Formulation Development and Evaluation of Herbal Antifungal Cream by using Psidium guajava Leaf Extract

Fungal infection is one of the major health concerns globally and varies from superficial to systemic infections. Psidium guajava Linn. leaf extract showed antifungal activity against wide range of fungi. The present research focuses on the development and investigation of cream with guava leaf extract. Ethanolic, methanolic and hydroalcoholic leaf extract was evaluated for total flavonoid content, thin layer chromatography (TLC), high-performance thin layer chromatography (HPTLC) and antifungal activity against Candida albicans. Further cream-based extract was optimized using 32 factorial designs. Beeswax and tween 80 were selected as the independent variables whose impact was studied on viscosity and %cumulative drug diffusion. Optimized cream was characterized by appearance, pH, washability, spreadability, in-vitro drug diffusion study, antifungal test and skin irritation test on wistar rats. The hydroalcoholic extract showed the highest content of flavonoids and a better zone of inhibition (27 ± 1 mm). HPTLC results confirmed the presence of essential flavonoids. Cream with 6% beeswax and 5% tween 80 with a viscosity 10420 cP and 70% drug diffusion was considered as optimized batch. The prepared cream showed satisfactory results for all evaluated parameters. The antifungal test showed the highest zone of inhibition for cream (25 mm) in comparison to standard formulation (23 mm). No any sign of skin irritation was observed. The prepared formulation is the best suitable alternative for the available topical antifungal formulation

Green synthesis of MnO2 nanoparticles from Psidium guajava leaf extract: Morphological characterization, photocatalytic and DNA/BSA interaction studies

In this work, a simple, efficient and eco-friendly green synthesis of manganese dioxide nanoparticles (MnO2NPs) by Psidium guajava leaf extract was described. Fourier-Transform infrared spectra results revealed that involvement of the plant extract functional groups in the formation of MnO2NPs. The UV–vis absorption spectra of the synthesized MnO2NPs exhibited absorption peaks at 374 nm, which were attributed to the band gap of the MnO2NPs. Crystal phase identification of the MnO2NPs were characterized by X-ray diffraction analysis and the formation of crystalline MnO2NPs have been confirmed. Furthermore, scanning electron microscopy analysis showed that the synthesized MnO2NPs have a spherical in shape. Interestingly, the prepared green synthesized MnO2NPs showed catalytic degradation activity for malachite green dye. Malachite green's photocatalytic degradation was detected spectrophotometrically in the wavelength range of 250–900 nm, and it was discovered to have a photodegradation efficiency of 75.5 % within 90 min when exposed to solar radiation. Green synthesized MnO2NPs are responsible for this higher activity. An interaction between synthesized NPs and biomolecules, including CT-DNA and BSA was also evaluated. The spectrophotometric and Fluoro spectroscopic analyses indicate a gradual reduction in peak intensities and shifts in wavelengths, indicating binding and affinity between the NPs and the biomolecules.

Biogenic synthesis of dopamine/carboxymethyl cellulose/TiO2 nanoparticles using Psidium guajavaleaf 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.

In vitro anticariogenic activity of aqueous extract of Psidium guajava leaf against Streptococcus oralis – A dormant pathogen for dental caries

ABSTRACT Background: Dental caries is a complicated, multifaceted illness that affects teeth and leads to serious cavities both inside and outside the teeth. Aim: This study aims to determine the efficacy of Psidium guajava leaf extract against Streptococcus oralis. Materials and Methods: P. guajava leaves were extracted in water using the Soxhlet technique, and to identify the existence of several beneficial substances, phytochemical screening was carried out. The inhibitory properties of the aqueous extract were tested against S. oralis. Antimicrobial activity was determined by the agar well diffusion method. The minimum inhibitory concentration (MIC) was determined by the liquid dilution method, and the minimum bactericidal concentration (MBC) was determined by the agar plate method. Results: Qualitative analysis of phytochemicals by standard methods showed the presence of various bioactive compounds. Using the well diffusion method, it has been determined that P. guajava leaf extract has antibacterial activity against S. oralis. The determination of the MIC and MBC showed that the extract exhibited an antimicrobial effect against cariogenic bacteria. Conclusion: P. guajava leaf extract contains bioactive compounds that have a significant impact on the avoidance of dental cariogens. P. guajava leaf extract is effective against S. oralis.