Effect of Gum Arabic (Acacia senegal and Acacia seyal) addition on antioxidant properties and oxidative stability of roselle juice

Gum Arabic (GA) is the dried exudate obtained from the tree of Acacia senegal and Acacia seyal that possess a prebiotic effect on humans. Meanwhile, roselle is a popular juice that is rich in antioxidants. However, as a complex polysaccharide, the addition of GA in roselle juice may affect the antioxidant properties of the final product. Therefore, this study aimed to determine the effect of different types of GA (Acacia senegal or Acacia seyal) addition, at different concentrations (0%, 2%, 4% and 6%) on the antioxidant properties and antioxidant stability of roselle juice during storage. The most accepted formulation of juice for each GA type along with the control sample (0% GA) was analysed for their oxidative stability during five weeks of chill storage (4±1oC). Results showed that the addition of GA increased or at least maintained the vitamin C and total phenolic content (TPC) in the range of 11.35±1.26-25.18±1.70 mg/100 mL and 21.04±1.55-45.08±4.76 mg GAE/100 mL, respectively. Nevertheless, the addition of more than 2% of GA significantly reduced (p<0.05) about 7% to 25% of total anthocyanin content. Variation of results was shown by ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging activity (DPPH) assay. For storage study, all juices (0% GA, 4% A. senegal and 2% A. seyal) exhibited fluctuation in trend for all the antioxidant properties except for TPC which remained stable. In conclusion, overall findings showed the addition of GA may increase or at least maintain the antioxidant properties of the juices except for anthocyanin content and antioxidant activity (DPPH assay). Meanwhile, the addition of GA had a variation that resulted in the oxidative stability of juices during storage

Antioxidant and antibacterial activities in the fruit peel, flesh and seed of Ceri Terengganu (Lepisanthes alata Leenh.)

Malay cherry fruit or locally known as Ceri Terengganu (Lepisanthes alata Leenh.) is a local tropical exotic fruit and it is native to Malaysia. The Ceri Terengganu tree is widely distributed in the east coast of Peninsular Malaysia particularly in Terengganu, Pahang and Johor and commonly cultivated as an ornamental plant in the villages and gardens. A limited number of studies had been done on the proximate analysis and postharvest quality of Ceri Terengganu fruit, but the studies on the antioxidant and antibacterial activities of Ceri Terengganu fruit extract are still lacking. Hence, this study aimed to determine the antioxidant and antibacterial activity in the peel, flesh and seed extracts of Ceri Terengganu. The Ceri Terengganu was extracted using 60% ethanol and the total phenolic content (TPC), total flavonoid content (TFC), total monomeric anthocyanins, antioxidant and antibacterial activities were measured using standard methods. The results showed that the seed of Ceri Terengganu had the highest amount of TPC, TFC and antioxidant activity, followed by the peel and flesh extracts whilst the peel extract had the highest total monomeric anthocyanins content. Furthermore, all three extracts of Ceri Terengganu showed inhibition against selected pathogens tested. In conclusion, the seed of Ceri Terengganu possessed the greatest potential to be explored as a source of natural antioxidant and antibacterial agent in the food industry, and thus warrant further investigation.

Survival of antibiotic resistant Escherichia coli in vacuumpacked keropok lekor: Food safety alert among SME keropok lekor producers

The microbiological quality of thirty ready-to-eat (RTE) keropok lekor (a sausage shape Malaysian fish product) was evaluated in comparison to microbiological guidelines for ready to eat foods. The two E. coli isolates were subjected to DNA sequencing, identified and tested for their resistance towards fifteen different antibiotics. The survival and growth of the isolated E. coli strains inoculated in keropok lekor at atmospheric air and vacuum packaging were also evaluated. Results revealed that four samples (13.33%) contained Enterobacteriaceae counts that exceeded the recommended allowable counts of 4.0 log₁₀ CFU/g. Unsatisfactory level of coliforms (< 1.7 log₁₀ CFU/g) was also observed in ten of the samples; two of which contained E. coli (2.1 ± 0.17 and 3.7 ± 0.02 log₁₀ CFU/g), suggesting of poor hygiene and sanitation practices. While the 'Possible E10' E. coli strain was observably resistant towards Nalidixic acid (30µg) alone, B10 E. coli isolate was worryingly resistant towards Ampicillin (10µg), Ceftazidime (30µg), Ciprofloxacin (5µg), Ceftriaxone (30µg), Nalidixic acid (30µg) and Tetracycline (30µg). This study also revealed that the growth and survival of the 'Possible E10' and B10 E. coli strains were not significantly affected by vacuum packaging when stored at both 4°C and 28°C. Therefore, intervention programmes to alert and educate smallmedium enterprisers (SMEs) of keropok lekor producers on food safety as well as potential health risks that can be associated due to inappropriate handling procedures of such product, merits consideration.

Structural characterisation, citral retention and thermal properties of the inclusion complex of rice starch–lemongrass extract

The citral compound that contributes to the strong-lemony odour of lemongrass has high volatility and low physicochemical stability. To overcome the problems, the inclusion complex of the encapsulation technique was applied with rice starch as a coating material to improve the stability and protect against any unfavourable reaction. Therefore, this study was conducted to determine the structural characterization, citral retention and thermal properties of native rice starch, gelatinised rice starch, inclusion complex of rice starch–citral compound, and inclusion complex of rice starch–lemongrass extract. Lemongrass extract and standard citral compound were homogenised into rice starch dispersion at 80oC for 15 mins and freeze-dried at −50.0±2.0oC. The formation of the inclusion complex powder was determined using different analyses including morphological structure using the scanning electron microscope, crystallinity structure was determined with X-ray diffractometer, identification and quantification of citral compound using HS-SPME-GC-FID and the thermal properties of inclusion complex analyzed using differential scanning calorimetry. The microstructure of both inclusion complex of rice starch-lemongrass extract and rice starch-citral compound exhibited a laminated multiangular shape with crumble formation together with the characteristics of V-type pattern of crystalline complexes. The low degree of crystallinity of the inclusion complex of rice starch–lemongrass extract obtained high in citral entrapment (29.34±3.13%) with the highest concentration of citral retention (7.33±0.78 ppm). Both inclusion complex of rice starch-citral compound and rice starch-lemongrass extract displayed an endothermic peak at 138oC, which is attributed to an inclusion complex occurrence with significant difference (p<0.05) of enthalpy of 0.44±0.05 J/g and 1.61±0.70 J/g, respectively. These findings showed that rice starch was effective in complexing with aroma compounds in improving the stability and protecting the citral compound of lemongrass extract from any unwanted changes. This inclusion complex should be regarded as an important strategy in designing a novel model of citral compound of lemongrass for food flavouring application.ha

IgA nephropathy in patients with familial Mediterranean fever

Two patients with a long-standing history of familial Mediterranean fever were found to have both microscopic hematuria and proteinuria during the acute attacks. Kidney biopsies from both patients revealed diffuse mesangial proliferative glomerulonephritis with intense mesangial IgA and C3 deposits and no evidence of amyloidosis. To our knowledge these are the first 2 cases documenting the presence of mesangial IgA nephropathy in patients with familial Mediterranean fever.

The changing epidemiology of diphtheria in Jordan

Outbreaks of diphtheria used to occur regularly in Jordan, the last such outbreak being in 1977-78. Since that time, a massive immunization programme targeted at pre-school-age children has been markedly successful. Hence, when an outbreak of diphtheria occurred in 1982-83, it was unexpected. Of the 35 patients who were treated at the Jordan University Hospital, two died and the remaining 33 recovered uneventfully. Contrary to our findings in previous diphtheria epidemics in Jordan, this outbreak largely involved adolescents and young adults.