scholarly journals Antibacterial and Phytochemical Properties of Crude Leaf Extracts of Moringa oleifera Lam., Pterocarpus santalinoides L’Herit DC and Ceiba pentandra L. on Some Clinical Bacterial Isolates in Nigeria

2020 ◽  
pp. 1-15
Author(s):  
Reginald C. Njokuocha ◽  
Anthonia E. Ewenike
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Salmonella Typhi ◽  
Bacterial Isolates ◽  
Leaf Extracts ◽  
Ceiba Pentandra ◽  
Ethanolic Extracts ◽  
Pterocarpus Santalinoides

Aims: The study was carried out to determine the phytochemical constituents and antibacterial activity of aqueous and ethanolic extracts of fresh leaves of Moringa oleifera Lam., Pterocarpus santalinoides L’Herit DC and Ceiba pentandra L. on bacterial isolates; Salmonella typhi, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Methodology: The plant leaves were dried, pulverized and phytochemical tests were done according to standard laboratory procedure. Aqueous and ethanolic extracts were obtained from 20 g of the of the ground leaves. Antibacterial assay was carried out with Disc diffusion method on seven concentrations of the extracts ;100,50,25,12.5, 6.25,3.125,1.5625 mg/ml and compared with standard antibiotics. Isolated bacterial pathogens; Salmonella typhi, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa (1.0 x 105 cfu /ml) were used as test organisms. Results: Alkaloids, steroidal aglycones, glycosides, proteins, carbohydrates, reducing sugars, tannins, saponins, vitamins A and E were present in all the plant samples. Flavonoids and cardiac glycosides were not detected in Pterocarpus santalinoides and Ceiba pentandra, respectively. Anthracene glycoside was absent in all samples. Aqueous and ethanolic extracts of M. oleifera showed antibacterial activities against all the bacterial isolates at minimum inhibitory concentration (MIC) of 3.125 mg/ml and 1.5625 mg/ml respectively. Pterocarpus santalinoides showed inhibitory activity only on Salmonella typhi at 3.125 mg/ml and Escherichia coli 1.5625 mg/ml MIC. Ceiba pentandra showed spectrum of antibacterial activity against all the bacterial isolates at 1.56 mg/ml MIC with exception of Salmonella typhi. E. coli was the most susceptible to the leaf extracts. Salmonella typhi was not sensitive to the leaf extracts of Ceiba pentandra, while Staphylococcus aureus and Pseudomonas aeruginosa were not sensitive to the leaf extracts of Pterocarpus santalinoides. Conclusion: It can be concluded that both aqueous and ethanolic leaf extracts had antibacterial activity against the test organism, thus justifying their use in folklore medicine.

scholarly journals Antibacterial Activity of Solanum surattense Burm. F

1970 ◽  
Vol 6 (1) ◽  
pp. 1-4 ◽  
Author(s):  
E Sheeba
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Leaf Extract ◽  
Salmonella Typhi ◽  
Shigella Dysenteriae ◽  
Leaf Extracts ◽  
Solanum Surattense ◽  
Engineering And Technology ◽  
Ethanol Extracts

Ethanol extracts of Solanum surattense used in traditional medicine for treatmentof various infections. The antibacterial activity detected was againstStaphylococcus aureus, Streptococcus sp.; Bacillus subtilis, Escherichia coli,Pseudomonas aeruginosa, Salmonella typhi, Shigella dysenteriae and Vibriocholerae. The highest antibacterial activity was observed in 500μg concentrationof leaf extracts of all bacteria screened except Shigella dysenteriae. The minimumzone of inhibition observed in 25μg concentration of leaf extract exceptPseudomonas aeruginosa and Shigella dysenteriae. These results indicate that theextracts were bacteriostatic at higher concentrations.Keywords: Antibacterial activity; Solanum surattense; pathogenicmicro organisms.DOI: 10.3126/kuset.v6i1.3278Kathmandu University Journal of Science, Engineering and Technology Vol.6(1) 2010, pp 1-4

scholarly journals Synthesis and Evaluation of Some New Thiazolidin-4-One Derivatives as Potential Antimicrobial Agents

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
B. A. Baviskar ◽  
S. S. Khadabadi ◽  
S. L. Deore
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Antimicrobial Agents ◽  
Salmonella Typhi ◽  
Zone Of Inhibition ◽  
Structure Activity

A new series ofN-{4-methyl-5-[4-(4-oxo-2-phenyl(1,3-thiazolidin-3-yl)]-5-sulfanyl(1,2,4-triazol-3-yl)-1,3-thiazol-2-yl }acetamide (7a-l) was synthesized in order to determine their antimicrobial activity and feasible structure–activity relationships. The compounds were synthesized in good yield and the structures of all newly synthesized compounds were established on the basis of their IR,1HNMR, and elemental analysis. The synthesized compounds were testedin vitroantibacterial activity againstStaphylococcus aureus,Escherichia coli,Pseudomonas aeruginosaandSalmonella typhiand antifungal activity againstAspergillus niger,Candida albicansby measuring the zone of inhibition in mm.

scholarly journals KHẢO SÁT ĐIỀU KIỆN NUÔI CẤY ĐỂ NÂNG CAO KHẢ NĂNG KHÁNG KHUẨN CỦA CÁC CHỦNG Streptomyces sp.

2021 ◽  
Vol 5 (1) ◽  
pp. 2227-2236
Author(s):  
Nguyễn Thị Thủy Tiên ◽  
Lê Thị Thu Hiền ◽  
Trần Thị Lệ Ngân ◽  
Trần Văn Trung ◽  
Nguyễn Thị Thúc ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
16S Rrna ◽  
Bacillus Cereus ◽  
Salmonella Typhi ◽  
Streptomyces Sp ◽  
International Streptomyces Project ◽  
E Coli

Streptomyces là những vi sinh vật có khả năng sinh tổng hợp các chất kháng sinh. Nghiên cứu này nhằm sàng lọc và chọn chủng có khả năng kháng khuẩn cao nhất từ 59 chủng Streptomyces có nguồn gốc từ đất đã được cung cấp dựa trên phương pháp cấy vạch vuông góc đối với 5 vi khuẩn gây bệnh chỉ thị, bao gồm Bacillus cereus, Escherichia coli, Salmonella typhi, Staphylococcus aureus và Pseudomonas aeruginosa. Mười lăm chủng thể hiện hoạt tính kháng khuẩn ở các mức độ khác nhau, các chủng còn lại không thể hiện khả năng kháng. Chủng có khả năng kháng khuẩn cao nhất là HĐM3.2, kháng 4/5 vi khuẩn chỉ thị đã sử dụng, gồm B. cerius, S. aureus, S. typhi và E. coli với kích thước vùng kháng đạt 9,5, 10,5, 16,5 và 14,5 mm. Chủng HĐM3.2 được xác định là chủng Streptomyces sp. dựa trên cây phát sinh loài đã xây dựng của trình tự gene 16S rRNA. Điều kiện nuôi cấy để chủng HĐM3.2 thể hiện hoạt tính kháng khuẩn cao nhất đã được khảo sát dựa trên phương pháp khuếch tán qua giếng thạch. Môi trường International Streptomyces Project 2 có pH 8, nhiệt độ nuôi cấy 28oC là điều kiện thích hợp để chủng Streptomyces sp. HĐM3.2 tạo ra vùng ức chế các loại vi khuẩn B. cereus, E. coli, S. typhi, S. aureus cao nhất. ABSTRACT Streptomyces is the microorganism that has capable of producing antibiotics. The current study aimed to screen and to select a strain that had the highest antibacterial activity from 59 available soil-derived Streptomyces strains based on the perpendicular culture method on 5 indicator pathogenic bacteria, including Bacillus cereus, Escherichia coli, Salmonella typhi, Staphylococcus aureus và Pseudomonas aeruginosa. Fourteen strains exhibited their antibacterial activity at various levels, the remaining did not have that activity. The strain that had the highest antibacterial ability was HĐM3.2 against 4/5 indicator microorganisms, including B. cerius, S. aureus, S. typhi and E. coli with inhibitory areas were 9.5, 10.5, 16.5, and 14.5 mm respectively. Strain HĐM3.2 was identified as strain Streptomyces sp. based on a phylogenetic tree built on the 16S rRNA gene sequences. Suitable conditions that made the strain HĐM3.2 showed the highest antibacterial activity were investigated based on agar well diffusion assay. The medium of International Streptomyces Project 2 with pH 8, the ambient temperature at 28oC were suitable conditions for Streptomyces sp. HĐM3.2 produced the highest inhibitory areas against B. cereus, E. coli, S. typhi, S. aureus.  

scholarly journals Phytochemical Evaluation and Antimicrobial Potential Assessment of Some Spices on Selected Pathogenic Microorganisms in Alex Ekwueme Federal Teaching Hospital, Abakaliki, Nigeria

2021 ◽  
pp. 60-68
Author(s):  
D. O. Okata-Nwali ◽  
C. V. Uzoh ◽  
C. O. Okeh ◽  
B. Ugwu ◽  
O. J. Owolabi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Streptococcus Mutans ◽  
Salmonella Typhi ◽  
Herbaceous Plants ◽  
Klebsiella Pneumonia ◽  
Aqueous Extracts ◽  
Tetrapleura Tetraptera

The antibacterial activity of Monodora myristica, Xylopia aethiopica, Piper guineense, Tetrapleura tetraptera against selected human pathogens like Escherichia coli, Staphylococcus aureus, Klebsiella pneumonia, Pseudomonas aeruginosa, Salmonella typhi and Streptococcus mutans were ascertained using standard microbiological procedures. The herbaceous plants were sun dried and ground into powdery form. Fifty grams (50 g) each of the herbaceous plants were submerged into three (3) different extraction solvents (Ethanol, Methanol and Aqueous) in a conical flask, the flask were shaken intermittently for 24 hours. The herbaceous plants were sieved using whatman number one filter paper. The sieved extracts were allowed to air dry and the dried extracts were stored in a sterile sample bottle in the refrigerator until use. Agar well diffusion technique was used to determine the antibacterial activity/efficacy of the herbaceous plants. The antibacterial activity of ethanol, methanol and aqueous extracts of Azadirachta indica were determined. The result showed that aqueous extract had antimicrobial activity against all the test bacteria, ethanol extract had activity against Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli, but showed no activity against Pseudomonas aeruginosa, Streptococcus mutans and Salmonella typhi. Methanol extract had activity against Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli. Aqueous extract had activity similar to that of ethanol and methanol except that Streptococcus mutans which showed resistance to ethanol and methanol extracts was susceptible to aqueous extracts. Phytochemical analysis conducted shows that the herbaceous plant extracts contains substances such as alkaloids, saponin, tannin, flavonoid and phenol. The result obtained from this study revealed that these herbaceous extracts possess bioactive substances which had antibacterial activity on the test bacterial used in the study. Ethanol, methanol and aqueous extracts of Azadiractha Indica, Monodora myristica, Xylopia aethiopica, piper guineense, and Tetrapleura tetraptera had a remarkable activity against Staphylococcus aureus, E.coli and Klebsiella pneumonia while Pseudomonas aeruginosa, Streptococcus mutans and Salmonella typhi were resistant to both ethanol and methanol extracts. However, further in vitro and in vivo studies should be carried out to identify the active constituents responsible for their antibacterial activity.

Chemical Composition and Antibacterial Activity of Essential Oils of Three Medicinal Plants from Algerian Semi-Arid Climatic Zone

2018 ◽  
Vol 16 (S1) ◽  
pp. S155-S163 ◽  
Author(s):  
S. Mehalaine ◽  
O. Belfadel ◽  
T. Menasria ◽  
A. Messaili
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Chemical Composition ◽  
Essential Oil ◽  
Essential Oils ◽  
Rosmarinus Officinalis ◽  
Salvia Officinalis ◽  
Thymus Algeriensis

The present study was carried out to determine, for the first time, the chemical composition and antibacterial activity of essential oils derived from the aerial parts of three aromatic plants Thymus algeriensis Boiss & Reut, Rosmarinus officinalis L., and Salvia officinalis L. growing under semiarid conditions. The essential oils were chemically analyzed and identified by gas chromatography (GC) and GC/ mass spectrometry (GC/MS) and their antimicrobial activity was individually evaluated against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using both agar disk diffusion and agar dilution methods. The major constituents of Thymus algeriensis essential oil were identified as camphor (13.62%), 1,8-cineol (6.00%), borneol (5.74%), viridiflorol (4.00%), and linalool (3.93%). For Rosmarinus officinalis essential oil, 48 compounds were characterized, of which the main constituents were camphor (17.09%), Z-β-ocimene (10.88%), isoborneol (9.68%), α-bisabolol (7.89%), and borneol (5.11%). While, Salvia officinalis essential oil was characterized by β-thujone (16.44%), followed by viridiflorol (10.93%), camphor (8.99%), 1,8-cineol (8.11%), trans-caryophyllene (5.85%), and α-humulene (4.69%) as the major components. Notably, results from antibacterial screening indicated that Thymus algeriensis and Salvia officinalis essential oils exhibited a strong inhibitory effect against both Escherichia coli and Staphylococcus aureus compared to Rosmarinus officinalis essential oil. Further, less activity was recorded against Pseudomonas aeruginosa for the three tested essential oils.

ISOLASI DAN SKRINING AKTIVITAS ANTIBAKTERI DARI BAKTERI SIMBION NUDIBRANCHIA Phyllidiella pustulosa dan Thuridilla lineolata

2020 ◽  
Vol 8 (2) ◽  
pp. 40
Author(s):  
Ade Kurniawan Arie ◽  
Rosita A J Lintang ◽  
Remy E P Mangindaan ◽  
Agung B Windarto ◽  
Fitje Losung ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Symbiotic Bacteria ◽  
Bacterial Isolates ◽  
Defense Systems ◽  
Self Defense ◽  
Solid Media ◽  
Antibacterial Assay ◽  
And Staphylococcus Aureus

Nudibranchs are marine invetebrates belongs to the class of Gastropoda that are able to camouflage and develop a self-defense systems. Marine bacteria contain chemicals compunds that have potentials on marine drugs discovery through the secondary metabolism. The purpose of this study was to isolate the symbiotic bacteria from nudibranches Phylidiella pustulosa and Thuridilla lineolate and to screen the antibacterial activity of these bacterial isolates against Escherichia coli and Staphylococcus aureus. Isolation and culture of the symbiotic bacteria was made on B1 (solid) media. The results of the antibacterial assay showed that the symbiotic bacterial isolates from Phylidiella pustulosa and Thuridilla lineolate were able to inhibit the growth of the Staphylococcus aureus and Escherichia coli test. Keywords: nudibranch, Phyllidiella pustulosa, Thuridilla lineolate, bacteria, antibacterialAbstrakNudibranch adalah avetebrata laut dalam kelas Gastropoda yang mampu melakukan kamuflase dan mengembangkan sistem pertahanan diri. Bakteri laut mengandung senyawa kimia yang berpotensi sebagai bahan obat-obatan yang dihasilkan melalui metabolit sekunder. Tujuan dari penelitian ini yaitu untuk mengisolasi bakteri yang bersimbion dengan nudibranch Phylidiella pustulosa dan Thuridilla lineolate, kemudian mengamati aktivitas antibakteri dari isolat bakteri tersebut terhadap Escherichia coli danStaphylococcus aureus. Isolasi dan kultur bakteri yang bersimbion dibuat pada media B1 (padat). Skrining aktivitas antibakteri menunjukkan isolat bakteri yang bersimbion dengan nudibranch Phylidiella pustulosa dan Thuridilla lineolate mampu menghambat pertumbuhan organisme uji Staphylococcus aureus dan Escherichia coli. Kata kunci: nudibranch, Phyllidiella pustulosa, Thuridilla lineolate, bakteri, antibakteri

scholarly journals Jabuticaba skin extracts: phenolic compounds and antibacterial activity

2018 ◽  
Vol 21 (0) ◽  
Author(s):  
Flávia Cíntia de Oliveira ◽  
Tamara Rezende Marques ◽  
Gustavo Henrique Andrade Machado ◽  
Thaís Cristina Lima de Carvalho ◽  
Aline Aparecida Caetano ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Listeria Monocytogenes ◽  
Phenolic Compounds ◽  
Methanolic Extract ◽  
Ethanolic Extract ◽  
Salmonella Choleraesuis ◽  
Pharmaceutical Industries

Abstract The phenolic compounds from various extracts of jabuticaba skin powder (JSP) were characterized in this study, and the antibacterial activity assessed. The phenolic compounds were extracted from the JSP using four methods: a) acetone extraction - 1 g JSP: 10 mL 70% acetone, resting for 2 hours; b) aqueous extract - 1 g JSP: 15 mL water, under agitation; c) ethanolic extract - 1 g JSP: 15 mL acidified ethanol, under agitation; and d) methanolic extract - 1 g JSP: 50 mL 50% methanol, under reflux. The antibacterial activity was evaluated by the agar diffusion assay, using Escherichia coli ATCC 11229, Salmonella choleraesuis ATCC 6539, Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538 and Listeria monocytogenes ATCC 19117. The ethanolic and methanolic extracts showed the highest levels of phenolic compounds, especially of cyanidin chloride, catechin and epicatechin. The extracts did not inhibit the growth of Escherichia coli and Salmonella choleraesuis, but inhibited 30% of the growth of Pseudomonas aeruginosa with an extract concentration of 250 µg mL-1. Against Staphylococcus aureus and Listeria monocytogenes the highest inhibitory effect observed was 41.8% for the ethanolic extract, followed by 36% inhibition by the methanolic extract, thus revealing the potential of these extracts as possible alternatives for use in the food and/or pharmaceutical industries.

scholarly journals FLORAL EXTRACT OF Tibouchina granulosa (DESR.) COGN. PHYTOCHEMISTRY PROSPECTION, AND ANTIBACTERIAL ACTIVITY

2021 ◽  
Vol 5 (1) ◽  
pp. 1-9
Author(s):  
Antonio Carlos Pereira de Menezes Filho ◽  
Matheus Vinícius Abadia Ventura ◽  
Carlos Frederico de Souza Castro
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Enterococcus Faecalis ◽  
Floral Organ ◽  
Salt Formation ◽  
Bacterial Strains ◽  
Positive Results

Tibouchina granulosa is a species that blooms annually in several regions of Brazil. This species is still little explored in terms of phytocompounds in all organs of this plant, especially the floral organ. Flowers of T. granulosa were collected in the municipality of Rio Verde, Goiás, Brazil, in 2021. The hydroethanolic floral extract was prepared by maceration and qualitative phytochemical (colorimetric reactions and salt formation) and antibacterial analyzes performed and the results expressed in millimeters of inhibition at different concentrations in mg mL-1. Several phytochemical classes were observed with positive results, especially for alkaloids, phenolics, oxylates, saponins, carbohydrates and tannins. As for the bacterial assay, potential antibacterial activity was observed for all bacterial strains tested, except for Salmonella serovar Thyphymurium and serovar Enteritidis. Expressive inhibitions were observed for Enterococcus faecalis > Pseudomonas aeruginosa > Staphylococcus aureus and Escherichia coli at the highest concentrations between 100-50 mg mL-1. The floral extract of Tibouchina granulosa showed phytotherapeutic potential with the presence of several phytochemical groups and expressive antibacterial activity.

scholarly journals Emergence of Colistin Resistant Gram-Negative Bacteria in a Tertiary Care Rural Hospital in 2019

KYAMC Journal ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 87-90
Author(s):  
Abdullah Akhtar Ahmed ◽  
Nusrat Akhtar Juyee ◽  
SM Ali Hasan
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Tertiary Care ◽  
Salmonella Typhi ◽  
Rural Hospital ◽  
Gram Negative Bacteria ◽  
Bacterial Isolates ◽  
Colistin Resistance ◽  
Sensitivity Testing ◽  
Gram Negative

Background: Colistin-resistant Gram-negative bacteria is a rapidly emerging global threatgenerated a sense of public alarm. Objective: To combat this challenge a study was designedto evaluate the fast spreading infections by colistin-resistant pathogens in the tertiary care rural hospital of Bangladesh. Materials and Methods: To study isolation ofpathogenic gram-negative bacilli,clinical sample (n-640) of hospitalized patients of Khwaja Yunus Ali Medical College Hospital in Enayetpur, Bangladesh during the 1st quarter of the year 2019 were used. The bacterial isolates were screened for meropenem and colistin-resistance. Results: A total of 156 bacterial isolates were studied which included Escherichia coli (n-112), Klebsiella pneumoniae (n-14), Pseudomonas aeruginosa (n-27), and Salmonella typhi (n-3). Antibiotic sensitivity testing showed that 32/156(20%) and 119/156 (76%) isolates were resistant to meropenem and colistin, respectively. whereas 50/156 (32%) isolates were resistant to both antibiotics. Escherichia coli, K. pneumoniae, pseudomonas aeruginosa, and Salmonella typhi isolates respectivelywere 112/156 (72%), 14/156 (9%). 27/156 (17%), and 3/156 (2%). Conclusion: Colistin is typically used as salvage therapy, or last-line treatment, for MDR gramnegative infections.But there is worrisome therapeutic scenario in our study finding of colistin resistance is 76% in Gram-negative bacteria of the clinical isolates. The restricted and rational use of colistin drug is the need of hour. KYAMC Journal Vol. 11, No.-2, July 2020, Page 87-90

scholarly journals Composition and Antibacterial Activity of Essential Oils from Leaf, Stem and Root of Chrysanthemum parthenium (L.) Bernh. from Iran

2009 ◽  
Vol 4 (6) ◽  
pp. 1934578X0900400 ◽  
Author(s):  
Ali Shafaghat ◽  
Hajar Sadeghi ◽  
Khodamali Oji
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Essential Oils ◽  
Salmonella Typhi ◽  
Inhibitory Effects ◽  
Germacrene D ◽  
Leaf Oil ◽  
Main Components ◽  
Microdilution Broth

The water distilled essential oils from leaves, stems and roots of Chrysanthemum parthenium (L.) Bernh. were analyzed by GC and GC/MS methods. The leaf oil was characterized by a high amount of camphor (56.4%), whereas in the stem oil, camphor (26.0%), trans-β-ocimene (23.6%) and germacrene-d (15.0%) were the major constituents. The main components of the root oil were α-pinene (50.0%), trans-β-farnesene (13.8%) and bicyclogermacrene (11.0%). Antibacterial activity of the leaf, stem and root oil were evaluated using the microdilution broth method. The oils showed inhibitory effects on Escherichia coli and Salmonella typhi, but were not active against Staphylococcus aureus.

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