Open Access Original Research Article

Synergistic Inhibitory Activities and Enhancing Antibiotic Sensitivities of Lactobacilli from Rajshahi Traditional Curd

M. Khairul Islam, M. Abdul Alim Al-Bari, M. Shakhawat Hasan, Alam Khan, M. Kudrat-E-Zahan, M. Anwar Ul Islam

Journal of Advances in Biology & Biotechnology, Page 1-11
DOI: 10.9734/JABB/2015/15657

Context: Lactic acid bacteria particularly Lactobacilli are considered to be the most useful group of microorganisms for potential uses as biopreservatives. Lactobacilli preserve dairy foods like curds by producing various organic and inorganic compounds that are antagonistic to other microorganisms.

Objective: The current study is designed to evaluate the synergistic inhibitory activity of Lactobacilli against pathogenic bacteria which is important for increasing safety and better quality of curds. As probiotic bacteria have great potential as adjunct or alternative therapy in a range of infectious, inflammatory and allergic diseases, assessment of co-cultures of Lactobacilli is also important for the eradication of pathogenic bacteria by conventional antibiotics.

Materials and Methods: The co-cultures of Lactobacilli were screened for their inhibitory activities and antibiotic sensitivities against six pathogenic bacteria such as Shigella sonnei, Staphylococcus aureus, Bacillus cereus, Shigella dysenteriae, Escherichia coli and Bacillus subtilis by disc diffusion and broth microdilution methods. 

Results: Synergistic inhibitory effects of Lactobacilli co-cultures were observed against several tested pathogenic bacteria and significantly antibacterial activities were observed against S. aureus and S. dysenteriae. The tested Lactobacilli were shown to produce various antimicrobial compounds marked as bacteriocin-like inhibitory substances. The co-cultures of Lactobacilli prominently increased antibiotic sensitivities to various pathogenic bacteria.

Discussion and Conclusion: The antimicrobial compounds producing ability of Lactobacilli in co-culture inhibited common pathogenic organisms will help in producing safe and delicious dairy products. Co-culture with Lactobacilli can reveal novel treatment strategies for infectious diseases that are being increasingly more difficult to treat due to the global spread of antibiotic resistance.

Open Access Original Research Article

Effect of Biosurfactants Extracted from a Locally Fermented Milk (Pendidam) on Its Shelf Life

Mbawala Augustin, Pahane Mbiada Majesté, Mouafo Tene Hippolyte, Tatsadjieu Ngoune Léopold

Journal of Advances in Biology & Biotechnology, Page 12-22
DOI: 10.9734/JABB/2015/15025

Biosurfactants was extracted from a locally fermented milk (pendidam), characterized and their antimicrobial activity on Candida spp. and E. coli were determined. The results obtained show that the crude extract of biosurfactants exhibit emulsifying activity with an emulsification index of 61.11±1.37% and can reduce the surface tension of water from 69.22±0.35 mN/m to 59.41±0.59 mN/m. Their properties were not affected by exposure to high temperature (100ºC for 15 min), to high salinity (20% NaCl) and to a wide range of pH (2 to 12). Furthermore, the biosurfactants extracted showed antimicrobial activity against Candida spp. and E. coli with a Minimum Inhibitory Concentration (MIC) of 50 mg/mL and a Minimum Bactericidal and Fungal Concentration (MBC/MFC) of 100 mg/mL. The obtained biosurfactants reduced the microbial load of pendidam in a rate ranging from 12.97% to 62.21% depending on the concentration used, the type of microorganisms and the time. The higher reduction of the microbial load of pendidam was recorded with biosurfactants concentration of 100 mg/mL against total aerobic flora after 72 hours of preservation at room temperature. Considering the results obtained, biosurfactants are able to improve the microbiological quality of pendidam, increase its shelf life and these facts confirm their eventual use as food preservatives.

Open Access Original Research Article

In vitro Anti-leishmanial Activity of Polygonum glabrum Stem Extract on Leishmania tropica (KWH23) Strain

Hamid Ur Rahman, Tayyab Ur Rehman, Abid Ali, Syed Aizaz Ali Shah, Muhammad Ismail

Journal of Advances in Biology & Biotechnology, Page 23-28
DOI: 10.9734/JABB/2015/15204

Aims: The aim of current study is to evaluate the Polygonum glabrum aqueous extract for anti-leishmanial activity, with the hope to find less expensive and common drug for this neglected disease.

Study Design: In vitro Susceptibility of Leishmania tropica.

Place and Duration of Study: After Polygonum glabrum collection from District Mardan, further work was carried out in Parasitology Laboratory, Quaid-i-Azam University Islamabad, Pakistan from May 2013 to October 2013.

Methodology: Soxhlet apparatus was used for plant extraction followed by rotary evaporator to remove the solvent. Various concentrations of the plant extract were made. The flat bottoms 96 well ELISA plate was used for antileishmanial assay, amphotericin B was taken as positive control. The morphology and number of the promastigotes were monitored after each 24 hours. The LC50/90 was calculated using SPSS version 21.

Results: After 72 hours of incubation at 25±ºC promising results were shown by P. glabrum. The percent mortality recorded at different concentration (0.05 ug/ml, 0.5 ug/ml, 5 ug/ml, 50 ug/ml, and 500ug/ml) were (4.23±0.68, 19.16±0.56, 40.5±0.05, 68.1±0.76 and 100±0.00%) respectively. The LC50, LC90 and R2 values find out for the assay were 7.25 ug/ml, 227.4ug/ml and 0.97 ug/ml.

In comparison, the percent mortality shown by amphotericin B were 30.27±0.54, 45.12±1.10, 80.87±1.78, 100±0.00 and 100±0.00 with 0.35 ug/ml, 9.49 ug/ml and 0.91 values of LC50, LC90 and R2 respectively. The negative control has zero mortality.

Conclusion: The current investigation reveals that Polygonum glabrum extract possess activity against Lesihmania tropica. As crude form of P. glabrum extract showed promising antileishmanial results, P. glabrum and other members of the family need further investigation so that the pure bioactive antileishmanial compounds should be isolated with cost effective, promising results and less side effects.

Open Access Original Research Article

Antitrypanosomal Activities of Ethyl Acetate Extracts of Honey Bee (Apis mellifera) and Its Effect on Haematological Parameters of Trypanosoma brucei brucei Infected Rats

Oluwatosin Kudirat Shittu, Uju Elekwechi, B. Busari Musa, Bashir Lawal

Journal of Advances in Biology & Biotechnology, Page 29-35
DOI: 10.9734/JABB/2015/15970

Aims: Ethyl acetate extract of honey bee Apis mellifera (600 mg/kg/bw) was investigated for its effect on parasitemia and some haematological parameters in Trypanosoma brucei brucei infected rats.

Methodology: Five groups comprising of four mice per group were used in the study.  Group 1, 2 and 3 were infected prophylactic treated, infected early treated and infected standard drug (berenil) treated (3.5 mg/kg/day) respectively. Group 4 and 5 serve as negative control (infected not treated) and normal control (uninfected not treated) respectively. The crude extract was partially purified using column chromatography to give fraction 1-3.

Results: The administration of the crude extract shows reduced parasitaemia and extension of life span from 5 days infected not treated (control) groups to 14 and 15days for infected prophylactic and infected early treated groups respectively.  Also, the partially purified fraction 1 and 2 shows low parasitemia with survival of 6 days while that of fraction 3 is 3 days compared with infected untreated group which survive for 5 days. There were significant increase (p<0.05) in the haemoglobin (HB) concentration, packed cell volume (PCV), red blood cells (RBC) counts and white blood cells (WBC) counts of infected treated groups when compared with infected not treated group. Whereas, there was no significant difference (p<0.05) in the RBC and WBC counts of infected early treated group when compare with infected untreated group.

Conclusion: It can be deduced that methanol extract of Apis mellifera possessed antitrypanosomal activities with ameliorative effect against haematological symptoms of Africa trypanosomiasis.

Open Access Original Research Article

Organics to Enhance Emergence and Growth of Oil Bean (Pentaclethra macrophylla Benth) Seedlings

N. C. Onwubiko, C. A. Uka, A. A. Ngwuta, G. C. Onyishi, R. E. Keyagha

Journal of Advances in Biology & Biotechnology, Page 36-41
DOI: 10.9734/JABB/2015/15131

Insufficient seedlings supply caused by poor seed germination is one of the major problems in the propagation of tropical fruit tree crops. Pre-sowing seed treatment has been known to improve germination and seedling production under different environmental stressed conditions. Fortunately, organics plays an important role in regulation of many physiological and genetic processes. This study evaluated the effectiveness of pre- planting seed treatment in organics namely: banana sap, cassava effluent and fermented palm sap, soaked for 0, 2, 4, 6 and 8 hours to enhance seed germination and growth of oil bean (Pentaclethra macrophylla) seedling. The experimental design was a 3 x 5 factorial in completely randomized design with 6 replicates carried out in the screen house of the School of Agriculture and Agricultural Technology, Federal University of Technology, Owerri. Days to emergence, plant height and number of leaves were highly significant with the organic treatments. Generally, seed pre-treatment in organics improved the emergence, and growth of oil bean seedlings. Seeds soaked in banana sap recorded the highest percentage total emergence of 87.50 while six hours of soaking in cassava effluent significantly reduced the mean number of days to emergence to approximately 17 day.