Open Access Short Research Article

Screening and Identification of Lactic Acid Bacteria with D-tagatose Production Capability

Wen Li, Zhicheng Zhou, Jiaxiang Huang, Guoyan Zhang, Faisal N. Awad, Radhika Chandankere, Qi Guo, Xianghui Qi

Biotechnology Journal International, Page 1-6
DOI: 10.9734/bji/2019/v23i230074

Aims: D-tagatose is a natural ketohexose which can be used as a functional sweetener in foods, diary and beverages products. Isolation of new bacterial strains having the ability to produce D-tagatose is a continuously trending topic of research.

Study Design: Screening of strains with D-tagatose production by identification and determination of its ability to produce D-tagatose content.

Place and Duration of Study: School of Food and Biological Engineering, Jiangsu University between May 2018 and April 2019.

Methodology: We initially screened and identified the strains capable of producing D-tagatose through kimchi liquid, and determined the species and genetic characteristics of the strain by physiological, biochemical and molecular biological identification, and then determined the content of D-tagatose by high performance liquid chromatography. Finally calculate the ability of the strain to produce D-tagatose.

Results: In this study, 4 strains of lactic acid bacteria (LAB) were isolated from kimchi sample. The isolates were identified as Lactobacillus spp. (Lactobacillus plantarum, Lactobacillus fermentum and Lactobacillus salivarius) on the basis of morphological, physicochemical characteristics and analysis of 16S rDNA gene sequence. Because of the novelty, strain designated as L. salivarius UJS 003 was considered for D-tagatose yield. Fermentation of D-tagatose was carried out using galactose as substrate for 48 hr at 37 °C, and HPLC method was used to determine the yield. The experimental results exhibited a D-tagatose yield of 3.134 g/L by L. salivarius UJS 003.

Conclusion: The strain UJS 003 represented as a potent D-tagatose producer and could be useful in a variety of biotechnological and industrial processes, particularly food and beverage industries.

Open Access Original Research Article

Pathogenicity of a Strain of Streptococcus suis Type 2 to Mice and Swine Isolated from Jingzhou City

Mengjie Liu, Zongming Li, Xiaolin Yang, Guoping Liu

Biotechnology Journal International, Page 1-12
DOI: 10.9734/bji/2019/v23i230072

Aims: The objective of this study is to identify S. suis type 2 and evaluate the virulence of ZHJ01 strain isolation, and verity the clinical and pathological outcome of a systemic infection caused by one serotype 2 when simultaneously inoculated with ZHJ01 strain. We also want to clarify the epidemiologic, clinical, microbiologic characteristics and the pathogenesis mechanism of S. suis type 2 in Hubei province, China.

Study Design: Pigs suspected of being infected with S. suis in Jingzhou regions of Hubei province, China were studied. S. suis type 2 isolation was obtained from the suspicion of diseased pig. The case of S. suis type 2 was detected by the virulence factor amplification based on PCR detection and bacterial isolation, identification in the laboratory. According to the experimental infections of mice and piglets, pathogenicity of this S. suis type 2 isolation to mice and swine was monitored. This study was conducted in the key laboratory of pathogenic microbiology, College of Animal Science of Yangtze University, and Institute of Black Pigs Research, Yangtze University.

Methodology: Proper serological typing can be performed using a co-agglutination test. The typical colonies purificated and cultured were inoculated with Glucose, Lactose, Raffinos, Sorbitol, D (+)-sucrose, Trehalose, 6.5%NaCl, D (-)-Salicin, Hippurate, Esculin hydrate, V-p, etc., then the test results were recorded. Detection of virulence factors were performed using PCR amplification and DNA sequencing. S.suis type 2 isolation was inoculated to mice and piglets for the virulence test, and the observation of the clinical signs and pathological changes.

Results: The virulence factor of extracellular protein factor (EF) was determined from ZHJ01 strain based on PCR detection. Sequence analysis indicated that the isolate was very similar to nucleotide homology with others SS2 strains from different county or contries, and there was not much variation. LD50 of S. suis type 2 for mice was 2.5 x 107cfu. LD50 of S. suis type 2 for piglets was 3.92 x 109cfu.

Conclusion: The results show that Swine S. suis type 2 has a relatively strong pathogenicity to pigs in Hubei province, China. This study can be, in part, sufficient to explain the pathogenicity for ZHJ01 strain in area of Zhijing, Jingzhou city, China, which may provide insights into the pathogenesis SS2 and more valid data to support the development of S. suis vaccine as well as the epidemiological investigation, further monitoring and effective prevention to S. suis.

Open Access Original Research Article

Exploration on the Effectiveness of Radio Frequency Treatment and Flash Pasteurisation on Enzyme and Microbial Activity for Coconut Water Preservation

Gnana Moorthy Eswaran, Vidyalakshmi ., Tito Anand, Vincent Hema

Biotechnology Journal International, Page 1-7
DOI: 10.9734/bji/2019/v23i230073

The aim of this research work is to explore the effect of flash pasteurisation (FP) and radio frequency (RF) treatment on enzyme activity, microbial activity and physicochemical properties of matured coconut water (MCW). The process conditions for FP were treatment temperature and time in combinations. The process conditions for RF treatment were different electrode position with constant current load 0.8 A. The results obtained from these treatments reveal that FP conditions had significant effect on inactivation of natural microbial flora, polyphenoloxidase (PPO) and peroxidase (POD) activity. From the results it is observed that FP at 90°C for 10 minutes is better for complete enzyme and microbial inactivation than RF treated MCW. The result is also evident that PPO has higher thermal stability than POD. From observed results the study also concludes that, FP is a better option for enzyme and microbial inactivation but RF treatment was found superior for retaining physicochemical attributes.

Open Access Original Research Article

Effect of Black Seed (Nigella sativa) and Uziza (Piper guineense) Leaf on the Histology of the Liver of Wistar Albino Rats

Okoye Ngozi Franca, Ikiriko, Favour Ibiwari

Biotechnology Journal International, Page 1-11
DOI: 10.9734/bji/2019/v23i230075

Aim: This study was aimed at investigating the effects of aqueous extracts of both Nigella sativa and Piper guineense on the liver enzymes; alanine amino transferase (ALT), aspartate amino transferase (AST) and alkaline phosphatase (ALP). Also the effect of Nigella sativa and Piper guineense extracts on the histology of the liver of Wistar rat was also studied.

Materials and Methods: A total of twenty five Wistar rats were used for the study. The animals were grouped into five groups, each having five animals. They were induced with sucrose and margarine to cause high sugar levels and hyperlipidemia respectively except the positive control group which was fed normal feed. The groups were: the positive control group, the negative control group which were induced without treatment, the uziza leaf group which were induced and were treated with 2 ml of aqueous extract of uziza leaf, the black seed group which were induced and were treated with 2 ml of aqueous extract of black seed, and the black seed and uziza group which were induced and were treated with 2ml of aqueous extract of black seed and 2 ml of aqueous extract of uziza leaf. 

Results: The result showed that the extracts decreased the ALT and AST and ALP activities in the rats in a time dependent manner with highest decrease obtained on the third week of treatment with the extracts.  The ALT activity (U/L) on the third week of treatment showed for the, negative control (64.48 ± 0.22), uziza leaf (28.82 ± 0.12), black seed (32.65 ± 0.02), black seed and uziza leaf (16.04 ± 0.02) (p≤0.05). The decrease in activity for AST levels (U/L) on the third week of treatment, showed for the negative control (58.00 ± 0.02), uziza leaf (11.00 ± 0.01), black seed (12.00 ± 0.02), black seed and uziza leaf (8.00 ± 0.02).

Conclusion: It can be concluded that both uziza leaf and black seed have hepatoprotective effect on the liver.

Open Access Original Research Article

Effect of Process Variables on the Transesterification Process of Palm Oil Sludge to Biodiesel

O. A. Aworanti, A. O. Ajani, S. E. Agarry, K. A. Babatunde, O. D. Akinwunmi

Biotechnology Journal International, Page 1-14
DOI: 10.9734/bji/2019/v23i230076

In this research work, the optimum process variables (catalyst, methanol to oil ratio and reaction time) for transesterification of palm oil sludge (POS) to biodiesel were studied. The transesterification process was carried by mixture of palm oil sludge, methanol and catalyst with the help of magnetic stirrer at 300 rpm and at temperature of 60ºC. The catalyst used for the process was potassium hydroxide (KOH). One-Factor-at-A-Time was used to select the possible optimum levels of process variable that gives high biodiesel yield. The study was evaluated by five levels  of methanol-to-oil ratio (1:1 – 12:1), catalyst (0.1- 2%) and reaction time (30 – 150 min).The optimum process variables for transesterification of palm oil sludge (POS) to achieved maximum biodiesel yield  were found to be methanol to oil molar ratio of 12:1, catalyst loading of 1.5wt% and reaction time of 30 min. At this optimum conditions the maximum biodiesel yield was 61.2%. The biodiesel produced from transesterification of palm oil sludge was characterized in order to determine the properties of the product. The density of POS is 857.0 kg/m3, kinematic viscosity of 5.38 mm2/s, flash point of 180°C, pour point of -5°C, and Acid value of 0.17 mgKOH/g. The biodiesel produced from transesterification of palm oil sludge meets the EN 14214 and ASTM 6751 standard. Thus, this study will be helpful to determine an efficient and economical procedure for biodiesel production from non-edible raw materials with high free fatty acid.