Antibacterial Activity Of Extracts Research Articles

Phytochemical Analysis, Biological Activities, and Molecular Docking Studies of Root Extracts from Paeonia Species in Serbia.

Without being aware of their chemical composition, many cultures have used herbaceous peony roots for medicinal purposes. Modern phytopreparations intended for use in human therapy require specific knowledge about the chemistry of peony roots and their biological activities. In this study, ethanol-water extracts were prepared by maceration and microwave- and ultrasound-assisted extractions (MAE and UAE, respectively) in order to obtain bioactive molecules from the roots of Paeonia tenuifolia L., Paeonia peregrina Mill., and Paeonia officinalis L. wild growing in Serbia. Chemical characterization; polyphenol and flavonoid content; antioxidant, multianti-enzymatic, and antibacterial activities of extracts; and in vitro gastrointestinal digestion (GID) of hot water extracts were performed. The strongest anti-cholinesterase activity was observed in PT extracts. The highest anti-ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical potential was observed in PP extracts, whereas against DPPH (2,2-diphenyl-1-picrylhydrazyl radicals), the best results were achieved with PO extracts. Regarding antibacterial activity, extracts were strongly potent against Bacillus cereus. A molecular docking simulation was conducted to gather insights into the binding affinity and interactions of polyphenols and other Paeonia-specific molecules in the active sites of tested enzymes. In vitro GID of Paeonia teas showed a different recovery and behavior of the individual bioactives, with an increased recovery of methyl gallate and digallate and a decreased recovery of paeoniflorin and its derivatives. PT (Gulenovci) and PP (Pirot) extracts obtained by UAE and M were more efficient in the majority of the bioactivity assays. This study represents an initial step toward the possible application of Paeonia root extracts in pharmacy, medicine, and food technologies.

Antibacterial and Antioxidant Activities of Triterpenoids Isolated from Endemic Euphorbia arbuscula Stem Latex.

This research study aimed to investigate the chemical constituents and evaluate the antibacterial and antioxidant activities of stem latex extracts from the endemic medicinal plant Euphorbia arbuscula found on Socotra Island, Yemen. The study aimed to assess the potential medicinal and veterinary uses of this plant, representing the first evaluation of its properties. The stem latex was extracted using ethanol, and the resulting oil underwent analysis using GC-MS to identify eight compounds. In addition, chromatographic techniques were employed to isolate two triterpenoids, lanosterol and lupeol, from the stem latex. The structures of these compounds were confirmed using IR, MS, and NMR techniques. The antibacterial activity of the extracts and isolated compounds was evaluated against three bacterial strains using the disc diffusion method, revealing only weak antibacterial effects. The study also investigated the antioxidant activity using the DPPH assay, where the ethyl acetate extract exhibited the highest activity with an IC50 value of ±13.55 µg/mL, followed by the chloroform extract with an IC50 of ±21.87 µg/mL. These findings emphasize the potential of Euphorbia arbuscula in the development of new medicines, particularly due to its notable antioxidant activity. The research methodology employed a scientifically rigorous approach, utilizing a comprehensive range of analytical techniques. However, further investigation is required to fully assess the plant's potential as a therapeutic agent.

Antifungal and antibacterial activity of the extract from the fruit of Aiouea trinervis Meisn. (Lauraceae)

Aiouea trinervis is a Brazilian shrub species of the Lauraceae family. In this study, the antifungal and antibacterial activity of the hydroethanolic extract 70% of the fruit of A. trinervis on the genus Candida, Staphylococcus and Salmonella sp. was evaluated using the paper disk diffusion method. Antifungal activity was observed for C. albicans (7-4 mm) and C. tropicalis (11-3 mm), and in the antibacterial test for S. aureus (9-2 mm) and S. serovar Enteritidis (14-4 mm) in concentrations greater than 50 mg mL-1 of the hydroethanolic extract of the fruit. The results confirm the potential antifungal and antibacterial activity of the hydroethanolic extract of the fruit of A. trinervis.

Effect of Laurus nobilis on bacteria and human transforming growth factor-β1.

In this study, we aimed to determine the phenolic compounds, the antibacterial activity of extract from Laurus nobilis leaves, and its possible effect on transforming growth factor-β1 expression level in peripheral blood mononuclear cells. The phenolic components of Laurus nobilis were identified by the high-performance liquid chromatography method. The antibacterial activity of this extract was determined by disk diffusion and broth microdilution methods. The transforming growth factor-β1 expression was analyzed using the RT-qPCR method. Epicatechin was found in the highest amount and o-coumaric acid in the lowest amount. The half-maximal inhibitory concentration (IC50) was determined to be 55.17 μg/mL. The zones of inhibition and minimum inhibitory concentration for Staphylococcus aureus, Enterococcus faecalis, and Klebsiella pneumoniae were 15, 14, and 8 mm and 125, 250, and 1000 μg/mL, respectively. The change in transforming growth factor-β1 expression levels was found to be statistically significant compared with the control groups (p<0.0001). Laurus nobilis extract was found to be effective against bacteria and altered the expression level of transforming growth factor-β1 in peripheral blood mononuclear cells.

Phytochemical investigations of Pomegranate (Punica granatum) rind extracts and their antibacterial activity

Pomegranate (Punica granatum L.) is an ancient fruit rich in phytochemical bioactive compounds. Punica granatum L belonging to the family Punicaceae is described as an ingredient in remedies and is a widely used plant having medicinal properties. Having served as a symbolic fruit since ancient times, pomegranate (Punica granatum L) gained considerable recognition as a functional food in the modern era. Present study reports the phytochemical analysis which has been carried out on the peel (rind) extract. Rind of pomegranate (Punica granatum) was extracted using Methanol as solvents. Phytochemical investigations included qualitative detection of phytochemicals .This phytochemical investigation results shows the presence of phenols , tannins, flavonoids, coumarins, quinones, steroids, triterpenoids, and alkaloids in Methanol extracts.The antibacterial activity of extracts were also evaluated by agar diffusion method against Staph aureus, E.coli and Pseudomonas aeruginosa.Methanolic extracts of pomegranate rind was most effective in inhibiting the growth of Staph.aureus showing 22 mm of diameter of zone of inhibition followed by Ethanolic extract against Staph.aureus with 19 mm diameter of zone of inhibition followed by E.coli with 21 mm diameter of zone of inhibition by methanol extract and 17 mm of diameter of zone of inhibition by ethanol extract. Work is under progress on new emerging AI technologies for detailed analysis of phyto-chemicals in Punica granatum rind. AI provides new approaches for screening the main components and pathways of single herb or prescriptions, and predicting the mechanism of action.

Evaluating biochemical and pharmacological properties of Curcuma longa L. grown organically in two locations of Odisha, India: In vitro study

Organic farmers use nitrogen-fixing cover crops, herbicides, and biological fertilizers derived chiefly from animal and plant wastes. Curcumin levels are higher in this turmeric variety than in other types with differing pharmacological effects. Growing concerns about the safety of chemical fertilizers have heightened the need to identify locally adapted microbial strains that can be employed as a growth-promoting inoculum. Although research on the microbial diversity of the soil in Kandhamal and Koraput, India, was published, there is still a lack of information about the microbial community of the turmeric that is indigenous to these regions. This research compares and contrasts organically grown turmeric's growth-promoting and antibacterial activities with normally developed turmeric. This is a preliminary study that focuses on the microbiota communities of the study region. In vitro results showed that these properties have been shown to positively affect the development and nutritional content of studied turmeric plants; hence, they are regarded as key plant growth promoters. Using conventional and organic soil, both Kandhamal and Koraput rhizome sample was planted. The aqueous and methanolic rhizome extracts from both soil conditions were extracted. The Agar well diffusion method examined the rhizome extract's antibacterial activity. Bacteria were isolated and characterized from the rhizosphere and conducted various biochemical experiments. When tested against nine human pathogenic microorganisms, rhizomes harvested with vermicompost showed significantly increased antibacterial activity. The rhizospheric bacteria isolated from the organic soil region also help promote plant growth and development and provide adequate nutrients for growth and development. In every single experiment, the organically produced rhizome yielded superior results. The present study concludes that organic turmeric showed better and more effective results in increasing nutrient content, antibacterial activity and yield. Potential field applications necessitate more study into these rhizobacteria's molecular and functional characterization. Future improvements to biocontrol methods may come from studies examining the viability of deploying integrative, long-term bio-formulations in the field. The present research can potentially be used to investigate antibiotic synthesis by microbial communities in turmeric soil.

Antibacterial, Phytochemical and Antioxidant Activity of Gliricidia sepium Crude Extract against Human Pathogenic Bacteria

Aim: The present study is aimed at examine the antibacterial effect of crude extract of G. sepium to human pathogenic bacteria and its contents of its phytochemical and antioxidant properties.&#x0D; Place and Duration of the Study: The study was conducted in the Department of Science Laboratory Technology.  Ekiti State University Ado Ekiti Nigeria under ambient temperature and humidity between May and September 2023.&#x0D; Methodology: The collected plant sample was identified by Mr. Omotayo F.O. of the Department of Plant Science and Biotechnology at Ekiti State University Ado Ekiti, Ekiti State. The plant was oven dried at 61.9°C for two hours and thirty minutes, then ground into a fine powder using an electric blender after being airdried for four weeks in a cold environment. 100 g of powdered leaves were steeped in 500 ml of distilled water, N-hexane, dichloromethane, and methanol, respectively, to prepare the extracts. Following the mixes' filtration via muslin fabric. Salmonella typhi, Staphylococcus aureus, Escherichia coli, and Proteus vulgaris were obtained from Federal Teaching Hospital Ido Ekitti in Ekiti State, Nigeria. The antibacterial activity of was determined using the agar diffusion method.&#x0D; Results: The results of the crude extract's antibacterial activity showed that the water extract had the largest zone of inhibition (12.00 ± 1:00 mm) against E. coli, while N-hexane had the lowest zone of inhibition (3.33 ± 5.77 mm) against S. typhi and P. vulgaris. Phenol content ranged from the lowest (6.19±0.01) in water extract to the highest (47.19 ± 0.02) in DCME. The plant demonstrated good amount in the Ferric Reducing Antioxidant Power (FRAP) and DPPH scavenging assays. Methanol extract had the highest DPPH (23.53 ± 0.03) at the lowest concentration of 100 µg/ml, and it also produced the highest DPPH (62.63 ± 5.77) at the highest concentration of sample,     500 µg/ml. &#x0D; Conclusion: The present work highlights the possible use of G. sepium leaf extracts as a source of antibacterial agents that can be used to prevent human diseases.

Assessment of antibacterial activity and cytotoxic effects of in vitro and in vivo plant parts of a medicinal plant Gynura procumbens (Lour.) Merr.

The goal of this study was to evaluate the antibacterial and cytotoxic effects of both the in vitro and in vivo plant part extracts of the medicinal plant Gynura procumbens. An effective protocol for regeneration and callus formation was developed using nodal segments and regenerated leaf explants, respectively. The highest fresh and dry weight calli were produced after four weeks of culture on Murashige and Skoog (MS) medium containing 2.0 mg/L BAP and 2.0 mg/L NAA, while the most shoots were produced on MS medium containing 1.0 mg/L BAP and 0.5 mg/L IAA. The in vitro shoots developed roots on MS media with 0.1 mg/L IBA. The antibacterial activity of extracts against various bacteria was examined to determine their significance (p < 0.05). The least significant difference (LSD) test results showed that the regenerated leaf extract had the highest antibacterial activity while the callus extract had the lowest. The minimum bactericidal concentration (MBC) and the minimum inhibitory concentration (MIC) were also established. Regenerated leaf extract had the highest toxicity and the lowest lethal concentration (LC50) value (1.21 ± 0.03 μg/mL) in a brine shrimp lethality bioassay. In contrast, callus extract had the lowest toxicity and the highest LC50 (11.09 ± 0.4 μg/mL). In addition, the in vitro cytotoxicity test results revealed that the callus and field leaf extracts had anti-cell-proliferative properties. The regenerated leaf and stem extract, however, could induce cell growth.

Bioassay-Guided Assessment of Antioxidative, Anti-Inflammatory and Antimicrobial Activities of Extracts from Medicinal Plants via High-Performance Thin-Layer Chromatography.

Natural products and their analogues have contributed significantly to treatment options, especially for anti-inflammatory and infectious diseases. Thus, the primary objective of this work was to compare the bioactivity profiles of selected medicinal plants that are historically used in folk medicine to treat inflammation and infections in the body. Chemical HPTLC fingerprinting was used to assess antioxidant, phenolic and flavonoid content, while bioassay-guided HPTLC was used to detect compounds with the highest antibacterial and anti-inflammatory activities. The results of this study showed that green tea leaf, walnut leaf, St. John's wort herb, wild thyme herb, European goldenrod herb, chamomile flower, and immortelle flower extracts were strong radical scavengers. Green tea and nettle extracts were the most active extracts against E. coli, while calendula flower extract showed significant potency against S. aureus. Furthermore, green tea, greater celandine, and fumitory extracts exhibited pronounced potential in suppressing COX-1 activity. The bioactive compounds from the green tea extract, as the most bioactive, were isolated by preparative thin-layer chromatography and characterized with their FTIR spectra. Although earlier studies have related green tea's anti-inflammatory properties to the presence of catechins, particularly epigallocatechin-3-gallate, the FTIR spectrum of the compound from the most intense bioactive zone showed the strongest anti-inflammatory activity can be attributed to amino acids and heterocyclic compounds. As expected, antibacterial activity in extracts was related to fatty acids and monoglycerides.

Evaluation of Phytochemical Screening and Antibacterial Activity of Latana Camara Linn. Extract Used As Antibacterial Finish on Fabrics

The aim of the research was to evaluate the antibacterial activity of a crude extract from Latana camara L. on different types of fabric samples made of cotton, bamboo, and bamboo cotton. Lantana camara L. is a well-known weed and a popular ornamental garden plant that is widely utilized in traditional medicine all over the world. Acetate, ethanol, methanol, and petroleum ether were used as solvents to make the leaves crude extract. Escherichia coli and Staphylococcus aureus were used as test organisms for the crude extract's anti-bacterial activity, which was also used for phytochemical analysis. According to a phytochemical study, Latana camara L. extract contained alkaloids, flavonoids, phenol and tannin. As measured by inhibitory zones ranging from 09mm to 24mm, plant methanol extract demonstrated good antibacterial activity against test organism. Antibacterial activity of fabrics (cotton, bamboo and bamboo cotton) finished with plant extract revealed inhibitory zones excellent ranging from 23mm to 28mm against Escherichia coli and Staphylococcus aureus. The present findings imply the potential antibacterial activity of the plant. L. camara aids in the relief of inflammatory conditions and to be developed into standardized, safe, and affordable biomedical products and use as functional finish for home textiles.

ETHNO MEDICINAL SURVEY AND HEAVY METAL ANALYSIS ON MUD DAUBER NEST IN ZARIA, KADUNA STATE NIGERIA.

The emergence of pathogenic bacteria that are resistant to several antibiotics has recently presented a significant challenge to the healthcare system. Therefore, an alternative source of antimicrobial agents is needed. The study aimed to compare the antibacterial activities of aqueous and ethanol extracts of ripe and unripe fruits of red and yellow varieties of Anacardium occidentale against Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa and Staphylococcus aureus. Cold maceration method of extraction was used using water and ethanol. Antibacterial activities of the extracts against the isolates were evaluated by agar diffusion method while minimum inhibitory concentration (MIC) was determined using broth dilution method. In the determination of the antibacterial activities of all the extracts, the highest zones of inhibition were shown by ethanolic extracts of both ripe red cashew (25 mm) and yellow cashew (26 mm) against Escherichia coli. Both the aqueous and ethanolic extracts of unripe red and yellow cashew had no antibacterial effect against Klebsiella pneumoniae and Pseudomonas aeruginosa. As well, both aqueous and ethanol extracts of ripe red and yellow cashew and ethanolic extract of ripe yellow cashew inhibited all the test organisms. Minimum inhibitory concentration ranged from 50 to 150 mg/ml. At 100 mg/ml, both ethanolic extracts of ripe red and yellow cashew were bactericidal to Escherichia coli while aqueous extract of ripe red cashew was bactericidal to Escherichia coli at 150 mg/ml. The antibacterial activities of A. occidentale apple (fruit) extracts underscore the credence to the efficacy of their use as traditional remedy against some human ailments.

Antibacterial Activity of a Phenylpropanoid from the Root Extract of Carduus leptacanthus Fresen.

The emergence and rapid spread of antimicrobial drug-resistance microorganisms exacerbate the treatment of infectious diseases, underscoring the importance of finding new, safe, and effective drugs. In Ethiopia, the roots of Carduus leptacanthus have traditionally been employed to treat microbial infectious diseases The aim of this study was to evaluate the antibacterial activity of the root extract and its primary components against six bacterial strains (Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumonia). The extraction involved maceration of air-dried and powdered roots of C. leptacanthus with 80% methanol. The compound was isolated from the root extract using silica gel column chromatography and recrystallization in CHCl3/MeOH (9 : 1) and was characterized using ESI-MS and 1D-NMR spectroscopy. Antibacterial activity of the extract was assessed using agar well diffusion and broth microdilution methods. Syringin, a phenylpropanoid, was isolated and characterized from the extract of C. leptacanthus. The extract showed the most substantial efficacy against S. epidermidis (MIC = 5.33 mg/ml and inhibition zone diameter of 24 mm at 200 mg/m). Syringin also elicited antibacterial activity against S. aureus (MIC = 13.33 mg/ml), S. epidermidis (MIC = 16 mg/ml), and S. agalactiae (MIC = 16 mg/ml). Despite being tested up to a maximum concentration of 16 mg/ml, syringin did not exhibit antibacterial activity against the Gram-negative bacteria (P. aeruginosa, E. coli, and K. pneumonia). In conclusion, the findings suggest that syringin exhibits partial involvement in the root extract's antibacterial activity, thereby potentially supporting the traditional medicinal use of the plant.

Antibacterial Activities and Chemical Compounds of Plantago lanceolata (Ribwort Plantain) and Plantago major (Broadleaf Plantain) Leaf Extracts

Background: Plantago lanceolata L. (ribwort plantain) and Plantago major L. (broadleaf plantain) are widely used in ethnobotanical studies and for treating various diseases. This study aims to investigate the antimicrobial activity and chemical compounds of these plants. Methods: The leaf extracts of P. lanceolata and P. major were fractioned using different solvents. The phytochemical screening was carried out by the gas chromatography-mass spectrometry (GC-MS) method. The antibacterial activity of extracts was assessed using the disc diffusion method, and the minimum inhibitory concentration (MIC) and the minimum bactericidal concentrations (MBC) were measured by microtiter-broth dilution method. Results: The dichloromethane leaf extract of P. lanceolata and P. major showed the highest antibacterial activity against Salmonella paratyphi (diameter of the inhibition zone: 18.83 and 20.00 mm, respectively) at 100 mg/mL concentration. The lowest MIC was related to dichloromethane extracts of both plants against S. paratyphi (500 µg/mL). The lowest MBC (1000 µg/mL) was related to the dichloromethane extract of P. major against S. paratyphi. The main compounds of P. lanceolata leaf extracts were bis(2-ethylhexyl) phthalate (41.96%), 1-methoxy-3-(2-hydroxyethyl)nonane (32.69%), bicyclo[3.1.1]heptane, 2,6,6-trimethyl- (1.alpha.,2.beta.,5.alpha.)- (10.45%), and cycloheptasiloxane tetradecamethyl- (27.96% and 31.33%). The main compounds of P. major leaf extracts were eicosane (23.62%), cyclohexasiloxane dodecamethyl- (18.21%), 1-methyl-3-n-propyl-2-pyrazolin-5-one (18.08%), cycloheptasiloxane tetradecamethyl- (33.85%), and 1,2-benzisothiazole-3-acetic acid, methyl ester (34.26%). Conclusion: Fractionation of the methanolic leaf extract of P. lanceolata and P. major can help better isolate active components from these plants. The antibacterial properties of the extracts of two plants may be due to the presence of antibacterial compounds detected in GC-MS.

Total Phenolic Content, Antibacterial and Antiradical Properties of Bee Bread from Turkey

Pollen grains, honey, and lactic acid bacteria are combined to make bee bread, which serves as the hive's primary source of nutrition. This study evaluated a Turkish bee bread concerning the total phenolic content, antiradical, and antimicrobial activity against Bacillus cereus, Escherichia coli O157:H7, Staphylococcus aureus, and Salmonella Typhimurium. The Folin-Ciocalteu method was applied to determine the total phenolic content (TPC) in bee bread's aqueous extracts and DPPH was used to assess the extract's radical scavenging activity. The extract's antibacterial activity on foodborne bacteria were evaluated using minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The current study determined the TPC of bee bread to be 24.45 ± 3.75 g of GAE/mg. The DPPH assay results indicated that the water-soluble extract of bee bread (1 mg/mL) had a scavenging activity of 3.40±2.99%. In this study, the bee bread extract's antibacterial effect on S. aureus, E. coli, S. Typhimurium, and B. cereus in various concentrations (6.25 to 25 mg/mL). The bee bread contains phenolic compounds and showed antiradical activity. Also, it has antibacterial activity on all of the tested bacteria. This research contributes to the knowledge of the bioactive properties of this unexplored natural material.

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Antimicrobial drug resistance is gradually increasing throughout the globe, and there is practically no newer antimicrobial agent coming soon. Plant secondary metabolites are well known for their various biological activities, and there are few studies targeting mangrove plants. Thus, in this study, we aim to assess the effectiveness of the ethanolic extract of the flowers of Avicennia marina, a commonly found mangrove species in coastal regions, against multi-drug resistant (MDR) microorganisms. The study focused on evaluating the extract's antibacterial activity against Staphylococcus aureus (ATCC 29213), Escherichia coli (ATCC 25922), Escherichia coli (MDR), Klebsiella sp. (MDR), Acinetobacter sp. (MDR), Pseudomonas sp. (MDR). The results of the study demonstrated that the flower extracts of Avicennia marina exhibited noteworthy antimicrobial properties against all the tested MDR microorganisms. The plant contains several bioactive compounds, such as flavonoids, tannins, and alkaloids, which are believed to contribute to the observed antimicrobial effects. These findings indicate that Avicennia marina flowers could serve as a valuable natural source for developing antimicrobial agents that could combat drug-resistant bacterial infections. However, future studies should focus on evaluating the efficacy and safety of this extract in live organisms (in vivo) to determine its potential as a new drug for treating resistant infections.

Productivity and Phytochemicals of Asclepias curassavica in Response to Compost and Silver Nanoparticles Application: HPLC Analysis and Antibacterial Activity of Extracts.

The application of compost and metallic nanoparticles has a significant impact on the productivity and chemical composition of horticulture plants. In two subsequent growing seasons, 2020 and 2021, the productivity of Asclepias curassavica L. plants treated with various concentrations of silver nanoparticles (AgNPs) and compost was assessed. In the pot experiments, the soil was amended with 25% or 50% compost, and the plants were sprayed with 10, 20, and 30 mg/L of AgNPs. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), and dynamic light scattering (DLS) were used to characterize AgNPs. The TEM measurements of AgNPs showed that the particles had spherical forms and ranged in size from roughly 5 to 16 nm. Leaf methanol extracts (LMEs) were prepared from the treated plants and assayed against the growth of two soft rot bacteria, Dickeya solani and Pectobacterium atrosepticum. The maximum plant height, diameter, number of branches/plant, total fresh weight (g), total dry weight (g), and leaf area (cm2) was recorded when levels of 25% compost + AgNPs 20 mg/L, 25% compost, or 50% + AgNPs 20 mg/L, 25% compost + AgNPs 30 mg/L or 50% compost + AgNPs 20 mg/L, 50% compost + AgNPs 20 mg/L, 50% compost + AgNPs 30 or 20 mg/L, and 25% compost + AgNPs 30 mg/L, respectively, were applied. The plants treated with 25% or 50% compost + 30 mg/L AgNPs showed a high chlorophyll content, while the plants treated with 50% compost + AgNPs 30 mg/L or 20 mg/L showed the highest extract percentages. The highest inhibition zones (IZs), 2.43 and 2.2 cm, against the growth of D. solani were observed in the LMEs (4000 mg/L) extracted from the plants treated with compost (v/v) + AgNPs (mg/L) at the levels of 50% + 30 and 25% + 30, respectively. The highest IZs, 2.76 and 2.73 cm, against the growth of P. atrosepticum were observed in the LMEs (4000 mg/L) extracted from the plants treated at the levels of 50% + 30 and 25% + 30, respectively. Several phenolic compounds such as syringic acid, p-coumaric acid, chlorogenic acid, cinnamic acid, ellagic acid, caffeic acid, benzoic acid, gallic acid, ferulic acid, salicylic acid, pyrogallol, and catechol, as well as flavonoid compounds such as 7-hydroxyflavone, naringin, rutin, apigenin, quercetin, kaempferol, luteolin, hesperidin, catechin, and chrysoeriol, were identified in the LMEs as analyzed by HPLC with different concentrations according to the treatment of compost + AgNPs used for the plants. In conclusion, the specific criteria that were utilized to measure the growth of A. curassavica revealed the novelty of compost and AgNPs combination treatments, particularly at a concentration of 50% compost + AgNPs 30 mg/L or 20 mg/L, which is better for the growth and phytochemical production of A. curassavica in the field.

Antibacterial Activity of Selected Medicinal Plants and Therapeutic Potential of Bridelia micrantha on Excision Wound Infected with Pseudomonas aeruginosa in Rat

Bridelia micrantha (Hochst.) Baill (Euphorbiaceae) and Smilax krausiana Meisn. (Smilaceae) are traditionally used in tropical Africa to treat various diseases including infectious diseases, stomach pains, skin diseases and wounds. The study aimed to evaluate the antibacterial activity of Bridelia micrantha (Hochst.) Baill (Euphorbiaceae) and Smilax krausiana Meisn. (Smilaceae) extracts and the healing potential of the most active extract in a rat excision wound model infected by Pseudomanas aeruginosa. The crude extracts were prepared by maceration in ethanol. Phytochemical analysis was performed using standard methods. Antibacterial activities of extracts alone and the combinations of extracts with amoxicillin as well as the effect of osmotic stress on their activities were determined by the broth microdilution method against Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus. The therapeutic effect of the B. micrantha extract ointment was evaluated in a rat excision wound model infected by P. aeruginosa. Skin and eye toxicity tests were performed using the Draize method. The ethanol extract of B. micrantha (MIC = 512 - 1024 µg/ml) displayed the largest antibacterial activity compared with that of S. krausiana (MIC = 512 - 2048 µg/ml). The antibacterial activities of plant extracts and amoxicillin increased under osmotic stress conditions ((2.5% and 5% NaCl). B. micrantha extract showed indifference and antagonism effects with amoxicillin against the tested bacteria. The B. micrantha extract ointment yielded the shortest epithelization times, highest wound contraction rates and lowest numbers of colony forming units of P. aeruginosa at the infection site as compared with the standard drug (Baneocin) and blank (palm kernel oil). The antibacterial and wound healing effects observed may be attributed to the presence of polyphenols, flavonoids, anthocyanins, alkaloids, triterpenes, saponines and tannins found in the test plants. The results of this study clearly demonstrate the antibacterial activity of B. micrantha and S. krausiana as well as the wound healing potential of B. micrantha.

Antibacterial and Wound Healing Properties of Selected Cameroonian Medicinal Plants

Emilia coccinea (Sims.) G. Don. (Asteraceae), Erigeron floribundus (Kunth) Sch. Bip. (Asteraceae) and Hibiscus asper Hook.f. (Malvaceae) are used ethnomedicinally in tropical region of Africa to treat various diseases including infectious diseases, abscesses, skin diseases and wounds. The study aimed to evaluate the antibacterial activity of E. coccinea, H. asper and E. floribundus extracts and the healing efficiency of the most active extract in a rat excision wound model infected by Staphylococcus aureus. The plant extracts were prepared by maceration in ethanol. Secondary metabolites were detected in the extracts by using standard methods. Antibacterial activities of extracts alone and the combinations of extracts with amoxicillin as well as the effect of osmotic stress on their activities were determined against Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus by using broth micro dilution method. The therapeutic effect of the E. coccinea extract was evaluated in a rat excision wound model infected by S. aureus. E. coccinea extract (MIC = 256 - 512 µg/ml) displayed the largest antibacterial activities followed in decreasing order by the extracts of E. floribundus flowers and leaves (MIC = 256 - 1024 µg/ml), E. floribundus roots (MIC = 512 - 1024 µg/ml) and H. asper (MIC = 1024 µg/ml). The antibacterial activities of plant extracts and amoxicillin increased under osmotic stress conditions. E. coccinea extract showed additive effect with amoxicillin against pathogenic bacteria among which multidrug resistant strains. E. coccinea extract ointment yielded the shortest epithelization times, highest wound contraction rates and lowest numbers of colony forming units of S. aureus at the infection site as compared with the standard drug (Baneocin). Interestingly, this extract ointment is non-irritating to the skin and eyes. The observed biological activities may be attributed to the presence of groups of phytochemical compounds found in the test plants. The results of the present study demonstrate the antibacterial activity of the test plants as well as the healing efficiency of the E. coccinea extract ointment. E. coccinea can be used for the development of phytomedicines to treat wounds and infectious diseases particularly those caused by the tested bacteria. So, further studies are warranted.

Biotechnological product potential of Auxenochlorella protothecoides including biologically active compounds (BACs) under nitrogen stress conditions.

Nitrogen stress can influence microalgae's growth characteristics, and microalgae grown in nitrogen-deficient conditions may produce higher or lower levels of biotechnological products as a result of metabolic changes. In photoautotrophic and heterotrophic cultures, nitrogen limitation has been proven effective in promoting lipid accumulation. In spite of this, no study has demonstrated a significant correlation between lipid content and other biotechnological products such as bioactive compounds (BACs).This research examines a strategy for lipid accumulation as well as the potential production of BACs with antibacterial properties in parallel with that strategy. This concept involved the treatment of the microalga Auxenochlorella protothecoides with low and high concentrations of ammonium (NH4+). This particular experiment reached a maximum lipid content of 59.5% using a 0.8 mM NH4+ concentration, resulting in the yellowing of the chlorophyll levels. Agar diffusion assays were conducted to determine the antibacterial activity of different extracts derived from the biomass when stressed with different levels of nitrogen.Algal extracts prepared by a variety of solvents showed different levels of antibacterial activity against representative strains of both gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacteria. Among the extracts tested, 500mg/L ethyl acetate extract had the greatest antibacterial activity against Escherichia coli. In order to identify the components responsible for the extract's antibacterial activity, fatty acid methyl ester (FAME) analysis was performed. It has been suggested that the lipid fraction may be a valuable indicator of these activities since some lipid components are known to possess antimicrobial properties. In this regard, it was found that the amount of polyunsaturated fatty acid (PUFA) significantly decreased by 53.4% under the conditions with the highest antibacterial activity observed.

In Vitro Antibacterial Activity of Selected South African Plants against Drug-Resistant Staphylococci Isolated from Clinical Cases of Bovine Mastitis

Bovine mastitis in dairy livestock production is a serious economic problem causing milk production losses and increased management costs. Staphylococcus aureus and non-aureus staphylococcus (NAS) are important causes of bovine mastitis. Antimicrobial resistance can limit the control of mastitis pathogens. Antibacterial and cytotoxic activities of acetone and ethanol extracts of nine South African plants were determined against reference and drug-resistant staphylococci isolated from clinical cases of bovine mastitis. The nine plants, namely, Antidesma venosum, Elaeodendron croceum, Erythrina caffra, Indigofera frutescens, Pleurostylia capensis, Searsia lancea, Searsia leptodictya, Trichilia emetica, and Ziziphus mucronata, were chosen for research material. The antibacterial activity of extracts was determined using a serial microdilution method, while a tetrazolium-based assay was used to determine their cytotoxicity against Vero cells. The values of antibacterial minimum inhibitory concentration (MIC) obtained were promising, with MIC ranging between 0.01 and 1.41 mg/mL. Generally, acetone extracts of most plants had better activity than their ethanol counterparts. The S. aureus strains were more susceptible to all the extracts than the NAS strains. The plant extracts’ half-maximal toxicity (LC50) was higher than 0.02 mg/mL, which is the recommended cytotoxic cut-off concentration. The ethanol extract of E. caffra, which showed better MIC values than its acetone extract, had the highest mean selectivity index (SI) of 8.30. Among the plants tested, S. lancea exhibited the most potent antibacterial activity, suggesting its potential usefulness as a broad-spectrum antibacterial agent against staphylococci associated with bovine mastitis, at relatively non-cytotoxic concentrations. Therefore, it is recommended for further investigation.