Quality degradation is normally judge by monitoring independently the loss of a certain quality
attribute during storage. However, the rate of degradation for each of the quality attributes
present in a food product is not the same. This study focus on deterioration of vitamin C,
lycopene, total phenolics and antioxidant activity of ready-to-drink pink guava juice (PGJ)
during storage at elevated temperatures. Kinetic order, rate constant (k), activation energy
(Ea) and temperature coefficient (Q10) of the degradation were derived by applying Arrhenius
equation. The results obtained showed that freshly made PGJ contain 39.79±2.18 mg/100 mL
of vitamin C, 3.17±0.27 mg/L of lycopene, 28.08±4.11 mgGAE/100 mL of total phenolic
content (TPC) and 13.20±1.91 mMTE/100 mL of ferric reducing antioxidant power (FRAP).
All quality attributes measured in this study showed zero-order kinetic reaction. The results
also showed that FRAP has the highest Ea of 49.52 KJ/mol and Q10 of 1.80, followed by
vitamin C (Ea=41.49 KJ/mol; Q10=1.64), lycopene (Ea=31.75 KJ/mol; Q10=1.46), and lastly
TPC (Ea=14.11 KJ/mol; Q10=1.18). The predicted total depletion of each quality attribute
at refrigerated storage (5o
C) were 266 days for antioxidant activity, 158 days for vitamin C
and lycopene, and 63 days for total phenolics. This study provide useful information on the
degradation rate and availability of health beneficial and bioactive compounds present in fruit
juice beverage during storage.
There are many factors influencing the stability and color variation of natural colorant anthocyanin and pH is among the most significant factor. This study aims to determine the stability of the anthocyanins in freeze-dried Hibiscus sabdariffa, Melastoma malabathricum and Ipomoea batatas in various acidic pH (pH 2.0, 2.5, 3.0, 3.5, 4.0 and 4.5). Total monomeric anthocyanin, degradation index, color density and percent polymeric color were analyzed to determine anthocyanins degradation and their color variations. Among the samples, H.sabdariffa contain the highest monomeric anthocyanins (163.3 mg/L) followed by M. malabathricum (49.9 mg/L) and the lowest is I.batatas (13.8 mg/L). Monomeric anthocyanins from I.batatas were found to be very stable and not affected by changes in pH than in H. sabdariffa and M. malabathricum. However, degradation index (DI) of H. sabdariffa was the lowest with value of 0.365 ± 0.049 at pH 3.5. The lowest percentage of polymeric color (4.94 ± 0.64) was also shown by H. sabdariffa at pH 2.5 and maintained a deep red color with increasing pH indicating higher color stability compared to M. malabathricum and I. batatas. Overall, natural pigment in H. sabdariffa was found to be the most stable in both monomeric anthocyanin content and chromaticity properties. These results provided information that will further proven the potential usage of H. sabdariffa, M. malabathricum and I. batatas as natural coloring agents to replace the synthetic colorant in food and beverage industries.
The association of arsenical poisoning with the development of skin cancer is well-known. In Malaysia, arsenic has been shown to coexist with tin in tin-mining land. Our preliminary investigation has shown that the level of arsenic in well water from a tin-mining area is high. We report 3 patients with cutaneous lesions typical of chronic arsenical poisoning such as hyperpigmentation, keratoses and skin cancer. These patients have positive histories of previous domicility in tin-mining areas. We conclude that these patients developed chronic arsenical poisoning from drinking well water polluted with arsenic from the tin-mining soil.
We aim to identify clinicopathologic predictors for response to neoadjuvant chemotherapy and to evaluate the prognostic value of pathologic complete response (pCR) on survival in Asia. This study included 915 breast cancer patients who underwent neoadjuvant chemotherapy at five public hospitals in Singapore and Malaysia. pCR following neoadjuvant chemotherapy was defined as 1) no residual invasive tumor cells in the breast (ypT0/is) and 2) no residual invasive tumor cells in the breast and axillary lymph nodes (ypT0/is ypN0). Association between pCR and clinicopathologic characteristics and treatment were evaluated using chi-square test and multivariable logistic regression. Kaplan-Meier analysis and log-rank test, stratified by other prognostic factors, were conducted to compare overall survival between patients who achieved pCR and patients who did not. Overall, 4.4% of nonmetastatic patients received neoadjuvant chemotherapy. The median age of preoperatively treated patients was 50 years. pCR rates were 18.1% (pCR ypT0/is) and 14.4% (pCR ypT0/is ypN0), respectively. pCR rate was the highest among women who had higher grade, smaller size, estrogen receptor negative, human epidermal growth factor receptor 2-positive disease or receiving taxane-based neoadjuvant chemotherapy. Patients who achieved pCR had better overall survival than those who did not. In subgroup analysis, the survival advantage was only significant among women with estrogen receptor-negative tumors. Patients with poor prognostic profile are more likely to achieve pCR and particularly when receiving taxane-containing chemotherapy. pCR is a significant prognostic factor for overall survival especially in estrogen receptor-negative breast cancers.