Open Access Original Research Article

Lipolytic Lactobacillus Species from Camel Milk

Madhu Rathore, Kanika Sharma

Microbiology Research Journal International, Page 1-5
DOI: 10.9734/MRJI/2017/37299

Over the past few years, lactic acid bacteria (LAB) have received extensive consideration as probiotics. Probiotics concepts have gained so much of popularity and extend from traditional dairy products to a profitable market of probiotic health supplements and functional foods. Probiotics are known for their health benefits as well as their human friendly nature. Probiotic lactic acid bacteria with lipolytic activity can be helpful for people's suffering from high serum lipid level. Consumption of such products contained lipolytic probiotic lactic acid bacteria can help to reduce the occurrence of consequences associated with high serum level. In the present work, two bacterial isolates were purified from camel milk. Sequencing of 16S rDNA/D1/D2 domain of LSU rDNA or ITS region and BLAST analysis lipolytic bacterial isolates were identified as Lactobacillus plantarum and Bacillus, Innovation of this work is use of camel milk sample for isolation of lipid degrading probiotic Lactobacillus bacteria which is easily available in Rajasthan region. Lactobacillus spp purified from screened sample showed significant lipase activity hence probiotic formulation developed from the same can be helpful for those people suffering from complications associated with high lipid level.

Open Access Original Research Article

Antibacterial Screening of Two Indigenous Nigerian Spices; Piper guineense and Xylopia aethiopica

O. C. Anika, A. A. Unimke, D. R. Tiku, N. R. Isu

Microbiology Research Journal International, Page 1-11
DOI: 10.9734/MRJI/2017/35444

Leaf and fruit extracts of Piper guineense and Xylopia aethiopica were respectively evaluated for their antibacterial activities against two (2) organisms; Staphylococcus aureus and Pseudomonas aeruginosa. The antibacterial activity was measured by agar well diffusion method using 8 mm diameter cork borer. All the extracts except hot aqueous extract of P. guineense leaves showed antibacterial activity against the test bacterial isolates. Cold aqueous extract of X. aethiopica did not exhibit antibacterial activity against P. aeruginosa, also hot aqueous extract of X. aethiopica did not exhibit antibacterial activity against P. aeruginosa. The ethanolic extracts of P. guineense showed inhibitory activity against the two test bacterial isolates with zone diameter of inhibition that ranged between 12.5 mm to 28.0 mm, while X. aethiopicashowed activity with zone diameter of inhibition that ranged between 11.5 mm to 20.0 mm. The cold aqueous extracts of P. guineense showed antibacterial activity against both test bacterial isolates with zone diameter of inhibition that ranged between 12.0 mm to 25.0 mm, while X. aethiopica showed activity only against S. aureus with zone diameter of inhibition ranged between 9.5 mm to 19.0 mm. The hot aqueous extracts of P. guineense showed no antibacterial activity against the test organisms, while that of X. aethiopica showed activity only against S. aureus with zone of inhibition ranged between 9.0 mm to 25.0 mm. Amoxicillin and Ciprofloxacin antibiotics were used as positive controls, while the extracting solvents were used as negative controls. The phytochemical screening revealed the presence of saponins, flavonoids, and tannins and the absence of alkaloids in both spices studied. The MIC result revealed variability in the inhibitory concentration of each extract for both organisms tested. All active extracts ofPiper guineense where found to possess an MIC of 3.12 mg/ml, while the MIC range for all the active extracts of Xylopia aethiopica ranged between 3.12 mg/ml to 12.5 mg/ml. Based on this finding, these extracts show promise and form a primary platform for further phytochemical and pharmacological studies for use as alternative medicine.

Open Access Original Research Article

Anti-Quorum Sensing Activity of Tetracera scandens and Aleurites moluccana Leaf Extracts against Chromobacterium violaceum

John Paul Matthew D. Guzman, Larry V. Padilla

Microbiology Research Journal International, Page 1-10
DOI: 10.9734/MRJI/2017/37450

Aims: To test the efficacy of Tetracera scandens (L.) Merr. and Aleurites moluccana (L.) Wiild. methanolic leaf extracts on the inhibition of quorum sensing-dependent pigmentation of Chromobacterium violaceum.

Study design:  In-vitro quorum sensing inhibition design was conducted.

Place and Duration of Study: The study was conducted at the Biology Laboratory, College of Science, Pamantasan ng Lungsod ng Maynila between November 2015 to May 2016.

Methodology: The leaf extracts were obtained through soaking in methanol and subsequent rotary evaporation. Qualitative screening of the anti-quorum sensing activities of the extracts were done through Agar Well Diffusion Assay. The Minimum Quorum Sensing Inhibition Concentration was determined through two-fold serial dilution and then wells were streaked on Mueller-Hinton Agar plates to identify the Minimum Bactericidal Concentration. Disc Diffusion Assay was done to quantitatively measure the anti-quorum sensing activities of the leaf extracts.

Results: The crude methanolic leaf extracts of T. scandens and A. moluccana were able to inhibit quorum-sensing on C. violaceum. The anti-QS activities of both plants were comparable at their Minimum Quorum Sensing Inhibitory Concentrations (P>.05), however, weaker activities were observed against the positive control (= 0.001). The two extracts were partially active in inhibiting quorum sensing but were inactive in growth inhibition.

Conclusion: This study revealed that T. scandens and A. moluccana exhibit anti-quorum sensing activities against C. violaceum and these may be due to their phytochemical constituents, including flavonoids, terpenoids, and phenolics, which were previously proven to exhibit anti-quorum sensing activity. Extensive studies on the isolation of these compounds which may be responsible for their activities may be required to further improve the efficacy and harness the potential of these plants on quorum sensing inhibition.

Open Access Original Research Article

Nutrient Enrichment of Agro–Industrial Waste Using Solid State Fermentation

Osama A. AboSiada, M. S. Negm, M. E. Basiouny, M. A. Fouad, S. Elagroudy

Microbiology Research Journal International, Page 1-11
DOI: 10.9734/MRJI/2017/36125

Agro-industrial wastes are generated during the industrial processing of agricultural crops. Agro-industrial wastes are estimated to over 30% of worldwide agricultural productivity every year. The main aim of this study is improve of protein content and nutritional value of agro-industrial wastes by solid state fermentation to use as animal fodder. Fungal strain Trichoderma reesei were used with five different substrates from agro-industrial wastes, namely; peels of mango, orange, apple, banana and tomato. pH5 is the optimum condition for protein enrichment in different waste types. Crude protein content in fermented substrates with Trichoderma reesei increased from 23.35%, 21.88%, 24.13%, 16.19%, 9.5% to 78.17%, 30.05%, 28.84%, 19.82% and 14.06% for peels of tomato, mango, orange, apple and banana respectively. Tomato peel had the highest value of crude protein, so could be a good substrate for production of crude protein by Trichoderma reesei.

Open Access Original Research Article

Biochemical Characteristics of Immobilized Chitinase from Alternaria infectoria

Hamed M. El-Shora, Salwa A. Khalaf, Suzan A. H. El-Sheshtawi

Microbiology Research Journal International, Page 1-10
DOI: 10.9734/MRJI/2017/36263

This research aimed to purify and immobilize chitinase from Alternaria infectoria and to study its biochemical characteristics for biotechnological applications. Chitinase (EC. 3. 2. 1. 14) was purified by ammonium sulphate precipitation, DEAE-cellulose and then Sephadex G-200 with specific activity of 51.9 U mg-1 protein. The pH values were 7, 8 and 9 for the free, silica gel –immobilized and entrapped enzyme. The optimal temperatures were 40, 50 and 60°C for the three forms of chitinase, respectively. The activation energy values were 43.2, 30.8 and 11.6 KJ mol-1. Ca2+ was activator whereas Hg2+, Cd2+ and Ni2+ were inhibitors. However, K+ and Mg2+ showed no remarkable effect. The immobilized chitinase retained appreciable activity after 8 cycles particularly entrapped enzyme. The entrapped chitinase expressed higher stability against desorptivity by SDS than silica gel-immobilized enzyme. Thus, the results reveal that immobilized chitinase expressed higher thermostability compared to the free enzyme and this was important for industrial applications.