Omar A. Alhaj

Discrimination between Bacillus and Alicyclobacillus Isolates in Apple Juice by Fourier Transform Infrared Spectroscopy and Multivariate Analysis

Alicyclobacillus is a causative agent of spoilage in pasteurized and heat-treated apple juice products. Differentiating between this genus and the closely related Bacillus is crucially important. In this study, Fourier transform infrared spectroscopy (FT-IR) was used to identify and discriminate between 4 Alicyclobacillus strains and 4 Bacillus isolates inoculated individually into apple juice. Loading plots over the range of 1350 and 1700 cm(-1) reflected the most distinctive biochemical features of Bacillus and Alicyclobacillus. Multivariate statistical methods (for example, principal component analysis and soft independent modeling of class analogy) were used to analyze the spectral data. Distinctive separation of spectral samples was observed. This study demonstrates that FT-IR spectroscopy in combination with multivariate analysis could serve as a rapid and effective tool for fruit juice industry to differentiate between Bacillus and Alicyclobacillus and to distinguish between species belonging to these 2 genera.

Antihypertensive effect of fermented skim camel (Camelus dromedarius) milk on spontaneously hypertensive rats

BACKGROUND Hypertension is one of the most common diseases in worldwide, thus prevention of hypertension is important in reducing the risks of cardiovascular disease. Milk contains bioactive peptides released during milk fermentation which lead to exhibit angiotensin I converting enzyme (ACE) inhibitory. OBJECTIVE The aim of this study was to investigate the antihypertensive effect of fermented skim camel milk on rats and compared with unfermented skim camel milk as control. METHODS The antihypertensive effect of fermented skim camel milk on thirty six male spontaneously hypertensive rats (SHR) was carried out for (short-term) and (long-term) using different doses (80, 240 and 1200 mg/kg body weight). Angiotensin converting enzyme (ACE) activity was also measured using ACE Kit. RESULTS The blood pressure (systolic and diastolic) of spontaneously hypertensive rats (SHR) in short term administration (24 hours) of 1200 mg/kg body weight fermented skim camel milk decreased significantly (p < 0.05) from 22 to 36 mmHg and 28 to 32 mmHg, respectively, at four and eight hour of post administration. On the other hand, the blood pressure of fermented skim camel milk for long-term (20 days) decreased and affected the heart rate (beats/min). The lowest record of systolic (41 mmHg) and diastolic blood pressure (19 mmHg) were at dose of 1200 mg/kg body weight of fermented skim camel milk at 15 days of administration. Likewise, ACE activity in plasma of SHR administered fermented skim camel milk decreased significantly (p < 0.05) compared with the control group. CONCLUSION The hypotensive effect of fermented skim camel milk by L. helveticus and S. thermophillus in SHR rats depends on the high dose of fermented skim camel milk in short and long-term. The ACE activity inhibitory was clear with fermented skim camel milk.

Identification of potential ACE-inhibitory peptides from dromedary fermented camel milk

ABSTRACT Camel milk is a good nutritional source for people living in the arid and urban areas. This study aim to identify ACE-inhibitory peptides from dromedary camel milk produced using Lactobacillus helveticus or Lactobacillus acidophilus. Ten ACE-inhibitory peptides were identified using HPLC-MALDI-TOF MS. L. helveticus strain was found superior in respect to production of ACE-inhibitory peptides, compared with L. acidophilus due to having high proteolytic activity. However, all identified amino acid sequences were corresponding to β-casein of camel milk (Camelus dromedarius). Furthermore, molecular mass of identified peptides were below 1200 Da. Some ACE-inhibitory peptides were found to remain stable for up to 15 d of storage.