Antimacrobial Properties of gynura procumbens (Sambung Nyawa) leaves In methanolic and acidic extracts

Introduction: Gynura procumbens, commonly known as ‘sambung nyawa’ in Malaysia has been used traditionally as remedies for anti-inflammatory, anti-hyperlipidimic and anti-hyperglycemic. The purpose of the present study was to qualitatively evaluate the antimicrobial effects of Gynura procumbens extracts. Methods: The sample was extracted using methanol and acid hydrolysis. The antimicrobial effects of the sample were determined by disc diffusion method against two bacteria and two fungi namely E. coli, S. aureus, C. albicans and S. cerevisiae. Results: The results showed that the acidic extract of G. procumbens has positive reactions towards E. coli, S. aureus and C. albicans with the presence of zone of inhibition at the concentration of 150 mg/mL. Following the positive reaction, the minimum inhibitory concentration (MIC) of the acidic extract was then evaluated by broth dilution method. The MIC of E. coli and S. aureus were determined at concentration 37.5 mg/mL and 75 mg/mL for C. albicans. It indicated that acidic extracts at lower concentration could inhibit the bacteria, but high concentration of extracts was required in the inhibition of the fungi. Conclusion: It can be concluded that, the present study proves that there is potential of antimicrobial effects in Gynura procumbens leaves extracts

Total phenolic content and antioxidant activity of roselle (Hibiscus sabdariffa) extracts

Introduction: Roselle (Hibiscus sabdariffa) is widely known for its benefits and medicinal properties. The aims of this study were to determine the total phenolic content (TPC) in H. sabdariffa extract, its antioxidant activity and relationship between TPC and its antioxidant scavenging capacity. Methods: The TPC value for each extract of free, bound soluble and bound insoluble phenolic acids was determined by using Folin-Ciocalteu assay. The antioxidant scavenging capacity was evaluated by using DPPH assay. Results: The results obtained in this study showed that bound soluble phenolic acids (7.63 + 0.28 mg GAE/g DW) had the highest TPC value than the free and insoluble phenolic acid extracts (2.78 + 0.20 mg GAE/g DW and 3.61 + 0.85 mg GAE/g DW, respectively) (p<0.05). As for the IC50 values, bound soluble phenolic acid extract exhibited the greatest value(0.62%) as compared to the free and bound insoluble phenolic acid extracts (0.90% and 1.14%, respectively). A positive correlation (R2 = 0.956) between three extracts (free, soluble and insoluble phenolic acids) of TPC and antioxidant radical scavenging capacity (DPPH) was obtained. Conclusion: It can be concluded that phenolic acids in H. sabdariffa extracts have an effect to the antioxidant scavenging capacity particularly in the bound soluble form. This finding proved that H. sabdariffa extracts could be a good source of natural antioxidant for food, cosmetic and pharmaceutical industries

Relationship between traditional Malaysian vegetables (ulam) intake and cognitive status among middle-aged adults from low cost residential areas

Ulam is fresh traditional Malaysian vegetables which normally consumed in raw form or after a short blanching process. It contains high antioxidants and polyphenols. However, there is limited study about the relationship between ulam consumption and cognitive status. Thus, a cross sectional study was conducted to determine the relation with cognitive function among 132 middle-aged Malays adults (45-59 years old), recruited by convenient sampling from low income residences in Klang Valley. Respondents were interviewed to obtain data on sociodemography, dietary intake and total ulam intake and also measured for anthropometric parameters at respective community centres. Cognitive status was measured using Digit Span (attention and working memory), Rey auditory verbal learning test (RAVLT) (verbal memory) and comprehensive trail making test (CTMT) (cognitive flexibility). The average ulam intake by the respondents was 15.1 ± 8.2g/day and the top five highest consumed ulam were petai (68.1%), pucuk paku (62.9%), ulam raja (56.8%), pegaga (54.6%) and kesum (44.7%).There was a significant correlation between ulam intake with Digit Span (r = 0.265, p = 0.006), total immediate recall of RAVLT (r = 0.427, p < 0.001) and CTMT (r = 0.257, p = 0.007). Analysis of multiple regression indicated that total ulam intake was a significant predictor for Digit Span (R2 = 0.152, p < 0.05), RAVLT (R2 = 0.335, p = 0.001) and CTMT (R2 = 0.310, p < 0.001). In conclusion, this study showed that ulam has the potential to protect against cognitive decline, however, randomized control trials should be conducted to determine the efficacy of the ulam as neuroprotective agent

Biodiesel production from waste cooking oil: a brief review

Biodiesel is a source of new renewable energies and a substitute fuel with much potential in the future for petroleum-derived diesel. According to BP Statistical Review of World Energy, total global consumption of diesel from petroleum increasing in one decade which is 3.5 million tonnes in 2010 and 3.9 million tonnes in 2019. Despite reducing the dependence on fossil fuel, the question of how waste cooking oil (WCO) disposal and related environmental damage issues might be solved by biodiesel production. In Malaysia, an estimated 540 000 tonnes of WCO from vegetable and animal fats are discarded each year without being treated as wastes. WCO recognize as a raw material for biodiesel process and have a great potential. Biodiesel is made through a reaction between triglyceride and alcohol, with triglyceride being a raw material found primarily in plants and animals. Transesterification is the popular process of biodiesel production with low cost and mild reactions conditions. Some studies have done on the variable of trans- esterification process with the optimum condition of biodiesel production from WCO. This study exam- ines WCO as a raw material for biodiesel production, including the various variables of transesterification process and a comparison of WCO biodiesel and petroleum diesel

Sustainability study of the processing of kitchen waste as a potential source of biofuel: biodiesel production from waste cooking oil (WCO)

One of the most concerned components in world’s food system challenges is food waste, and it is partic- ularly a critical issue in developed countries. Waste cooking oil (WCO) is one of the liquid food wastes that are recyclable. A proper recycling practice of WCO helps to reduce the adverse impact on environ- ment and it can be reused by converting it into industrial products such as biodiesel and soap. With the rising in cost of crude oil in the global market and depletion of conventional fuel, the world also is in need of alternative fuel to fulfil the global rising of energy demands. This paper studies on the potential of WCO as a source of biofuel by converting it to biodiesel by transesterification process. The acid value of the WCO is determined using standard titration method, in which, if the percentage of FFA is more than 2%, in which the WCO needs to undergo pre-treatment process. Sodium hydroxide is used as a catalyst and methanol as the reacting alcohol in transesterification. The characteristics of the biodiesel produced were tested and compared with the standard specification of the biodiesel; ASTM D6751 and EN 14214. From the experiment conducted, more than 90% of biodiesel yield can be obtained from the waste cook- ing oil. The properties of biodiesel that undergoes more washing process, such as acid value, density, kinematic viscosity, and cloud and pour points have values typically close to the ASTM D6751 and EN 14214 biodiesel standards, which can be seen in Sample 1. Producing biodiesel from WCO is one of the alternatives of disposing these waste products as it gives beneficial impacts to the environment. Since WCO is biodegradable, economical, environmental friendly and always available, the economic fea- sibility of biodiesel production from waste cooking oil is viable

The effect of bioactive polyphenols from Anacardium occidentaleLinn. leaveson α-Amylase and dipeptidyl peptidase IV activities

Anacardium occidentaleLinn. (A. occidentaleL.) leaves possess bioactive polyphenols which are associated with antidiabetic potency for the management of type 2 diabetes mellitus (T2DM). In this study, free, soluble ester,and insoluble-bound phenolic fractions from young and mature leaves of A. occidentaleL. were extracted. Subsequently, all fractions were investigated for their inhibitory effect on α-amylase and dipeptidyl peptidase IV (DPPIV) activities. Both free (72.45 ± 3.6%) and soluble ester (83.40 ± 4.7%) phenolic fractions in the mature leaves extracts had significantly demonstrated greater α-amylase inhibitors than the young leaves. Likewise, soluble ester (4.09 ± 0.34 μg/mL) and insoluble-bound (4.87 ± 0.32 μg/mL) phenolic fractions in the mature leaves extracts were significantly more effective in inhibiting DPPIV than the young leaves. As for fractions comparison, insoluble-bound derived from the young leaves extract was a more potent α-amylase inhibitor than free and soluble ester phenolic fractions (p < 0.0001). Besides, soluble ester and insoluble-bound phenolic fractions showed a stronger inhibitor of DPPIV than the free phenolic (p < 0.001), irrespective of the maturity of the leaves. In conclusion, this study showed that A. occidentaleL. extracts possessed antidiabetic properties,which may potentially be used as an alternative treatment for T2DM management

Engineering conventional and engineering technology programs in Malaysian universities

One of the goals of the education system in Malaysia is to ensure the development of highly educated, highly skilled and strongly motivated human resources to fulfill the needs of the nation and the requirements of the industry as well as to support the country's aspiration to be an industrialized nation. Thus, several government-funded universities in Malaysia are required to offer engineering technology programs. These universities are known as Malaysian Technical Universities Network (MTUN), comprising Universiti Teknikal Melaka, Universiti Malaysia Pahang, Universiti Tun Hussein Onn and Universiti Malaysia Perlis with a mission to educate and train highly skilled manpower that can contribute to the world class industrial nation. The purpose of engineering technology programs is to complement existing engineering conventional programs. This study reports the differences between engineering conventional programs and engineering technology programs in terms of curriculum design and delivery and assessment of student learning. This knowledge is important as it will differentiate the job scope of the graduates from both programs. The data collection method in this study was qualitative method involving document analysis and focus group interviews. The documents analyzed were Malaysian Qualifications Agency Program Standards for Engineering and Engineering Technology and Malaysian Engineering Program Accreditation Manual. The teaching staffs from MTUN were interviewed for data triangulation. The results indicate that there exist differences in the curriculum design and delivery and assessment of student learning for both programs

Methodology approaches and challenges in population‐based longitudinal study of a neuroprotective model for healthy longevity

Aim: The 36‐month Long‐Term Research Grant Scheme project: Towards Usual Aging – Neuroprotective Model for Healthy Longevity among Malaysian Elderly was designed to address multidimensional aspects including psychosocial, biophysical health, nutrition and dietary pattern, and auditory and visual function to highlight the magnitude of these associations in a single study. Methods: A total of 2322 respondents aged ≥60 years were recruited at baseline using the multistage sampling method, followed up at 18 months and 36 months. Results: Response rates at baseline, 18 months and 36 months were 87.8%, 77.3% and 67.1%, respectively. At baseline, the prevalence of successful aging, usual aging and mild cognitive impairment was 11%, 73% and 16%, respectively. The prevalence of single and multimorbidity at baseline were 25.9% and 50.3%, respectively. The incidence rates of mild cognitive impairment at 18 months and 36 months were 6.5 and 5.6 per 100 person‐years. The incidence rates of multimorbidity at 18 months and 36 months were 23.7 and 21.5 per 100 person‐years, respectively. Conclusions: The Long‐Term Research Grant Scheme project: Towards Usual Aging study provides an opportunity to investigate the interactions between wide ranges of aspects of the older population in a nationally representative sample of the older population

Antioxidant capacity of the green leafy vegetables using oxygen radical antioxidant capacity (ORAC), 2,2'-Azino-Bis (3Ethylbenzothiazoline-6-Sulphonic Acid (ABTS) and 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) assays

Antioxidants are believed to play a very important role in the body defence system against reactive oxygen species (ROS), the harmful by-products that are generated during normal aerobic cell respiration. The objective of this study was to determine the antioxidant capacity in green leafy vegetables using ORAC, ABTS, and DPPH assays of different polyphenol fractions (free phenolic, alkaline hydrolysate, acidic hydrolysate).The antioxidant capacity of the identified free and bound phenolic acid content was measured using different assays including ORAC, ABTS, and DPPH assay (end-point assay and kinetic assay). Only hydrophilic antioxidant activities of all selected samples were examined using ORAC assay. Strong correlations were observed in acidic and alkaline hydrolysate fractions (p<0.01) as determined by ORAC and ABTS assays, respectively. In the free phenolic acid extracts, the O. basilicum (Sweet basil) ranked first, had highest antioxidant capacities of 521804±4243 µmol TE/100g DW, 329.8±0.4mg TE/g DW and 9.0±1.8 µg GAE/g DW as determined by ORAC, ABTS and DPPH, respectively. . The A. occidentale (Cashew shoot) in the alkaline hydrolysate extract showed a greatest antioxidant capacity in all three assays: 889126±7193 µmol TE/100g DW, 466.5±7.9 mg TE/g DW and 3.5±0.4 µg GAE/g DW as measured by ORAC, ABTS and DPPH, separately. While, in acidic hydrolysate, the A. occidentale (Cashew shoot) extract also dominated the antioxidant capacity with (560504±5785 µmol TE/100g DW, 387±0.7 mg TE/g DW and 5.9±0.5 µg GAE/g DW) as determined by ORAC, ABTS and DPPH assays, respectively. The acidic and basic hydrolysis yielded higher antioxidant capacities in the present study. It suggests that hydrolysis with alkaline and acidic play significant roles in liberating more phenolic acids and flavonoids and generating high antioxidant capacity in the extracts

Profiling of bioactive compounds in Malaysian herbs

This study profiled selected phenolic acids, quantified total phenolic content (TPC) and antioxidant activities of five herbal plants namely Citrus hystrix, Coriandrum sativum, Murraya koenigii, Polygonum minus and Ocimum basilicum in phenolic fractions of free, soluble bound and insoluble bound. The TPC was quantified using Folin-Ciocalteu method and phenolic acids were detected using high performance liquid chromatography (HPLC). The antioxidant activities were determined using 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) and 2, 2’-Azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays. The result showed that gallic acid, caffeic acid, ferulic acid, sinapinic acid and p-coumaric acid were detected in distinctive proportion. For majority of plants, phenolic acids extracted from soluble and insoluble bound phenolic fractions had higher concentrations compared to free phenolic fraction. Of the plants tested, P. minus and O. basilicum showed higher total phenolic content and promising antioxidant activities in DPPH and ABTS assays. These antioxidant capabilities can be correlated with the presence of phenolic acids. In fact, there were strong correlation between TPC and both antioxidant assays. The significance of this study could be of important relevant in providing information of polyphenols composition and radical scavenging activity in various herbal plants