Norazlin Abdullah

Simplex-centroid mixture formulation for optimised composting of kitchen waste

Composting is a good recycling method to fully utilise all the organic wastes present in kitchen waste due to its high nutritious matter within the waste. In this present study, the optimised mixture proportions of kitchen waste containing vegetable scraps (V), fish processing waste (F) and newspaper (N) or onion peels (O) were determined by applying the simplex-centroid mixture design method to achieve the desired initial moisture content and carbon-to-nitrogen (CN) ratio for effective composting process. The best mixture was at 48.5% V, 17.7% F and 33.7% N for blends with newspaper while for blends with onion peels, the mixture proportion was 44.0% V, 19.7% F and 36.2% O. The predicted responses from these mixture proportions fall in the acceptable limits of moisture content of 50% to 65% and CN ratio of 20-40 and were also validated experimentally.

Effects of bulking agents, load size or starter cultures in kitchen-waste composting

BackgroundTo prevent the interruption of the carbon cycle by the disposal of waste to landfills, organic kitchen waste requires proper treatment such as composting to reduce its uncontrolled degradation on disposal sites and subsequent greenhouse gases, odour emissions and nutrient losses. This study investigated the effects of bulking agent, newspaper and onion peels, composting waste load sizes of 2 and 6 kg, or the use of starter culture on kitchen-waste composting consisting of nitrogen-riched substrates, vegetable scraps and fish processing waste in an in-vessel system. The optimised formulation of kitchen waste mixture was used for a 30-day composting study, where the temperature profiles were recorded and the carbon-to-nitrogen ratios were measured as an indication of compost maturity. The kitchen-waste composting process was conducted in parallel in two fabricated kitchen waste composters.ResultsIt was found that the onion peels were more suitable in producing matured compost where the carbon-to-nitrogen ratio reduced to 10 within 16 days of composting. A smaller kitchen waste load size of 2 kg gave a shorter composting time by half when compared to the 6 kg. The use of a microbial cocktail consisting seven types of bacteria and eight types of fungi isolated from soils as a starter culture for this kitchen-waste composting did not show advantages in accelerating the composting process.ConclusionsThe results suggest that the in-vessel kitchen-waste composting can be efficient with a minimal load of about 2 kg using onion peels without additional starter culture.

Anti-gout Potential of Malaysian Medicinal Plants

Gout is a type of arthritis that causes painful inflammation in one or more joints. In gout, elevation of uric acid in the blood triggers the formation of crystals, causing joint pain. Malaysia is a mega-biodiversity country that is rich in medicinal plants species. Therefore, its flora might offer promising therapies for gout. This article aims to systematically review the anti-gout potential of Malaysian medicinal plants. Articles on gout published from 2000 to 2017 were identified using PubMed, Scopus, ScienceDirect, and Google Scholar with the following keyword search terms: “gout,” “medicinal plants,” “Malaysia,” “epidemiology,” “in vitro,” and “in vivo.” In this study, 85 plants were identified as possessing anti-gout activity. These plants had higher percentages of xanthine oxidase inhibitory activity (>85%); specifically, the Momordica charantia, Chrysanthemum indicum, Cinnamomum cassia, Kaempferia galanga, Artemisia vulgaris, and Morinda elliptica had the highest values, due to their diverse natural bioactive compounds, which include flavonoids, phenolics, tannin, coumarins, luteolin, and apigenin. This review summarizes the anti-gout potential of Malaysian medicinal plants but the mechanisms, active compounds, pharmacokinetics, bioavailability, and safety of the plants still remain to be elucidated.

Polyherbal formulations with optimum antioxidant properties

The objective of this study is to determine the optimum antioxidant properties of polyherbal formulations of the aqueous extract of leaves of Strobilanthes crispus (pecah beling), Phyllanthus niruri (dukung anak), Orthosiphon aristatus (misai kucing) and Stevia rebudiana using in vitro method. There are 22 formulations consisting various proportions of the extracts designated using commercial statistical software package that is Design Expert 6.0.4. The antioxidant study of the individual extracts and their different combinations were conducted using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, Ferric Reduction Antioxidant Potential Assay (FRAP) and total phenolic content (TPC) assay. Results showed that O. aristatus has higher antioxidant properties in most of the assay when tested individually, as compared to S. crispus, P. niruri and S. rebudiana. Synergistic effect was exhibited in most of the polyherbal combinations. From the optimization process, it was revealed that the quadratic model was statistically significant for the FRAP and TPC while special cubic model was statistically significant for DPPH. The optimum mixture found for antioxidant properties was the polyherbal formulation that contain the extract of 23.96% of S. crispus, 0.62% of P. niruri and 75.42% of O. aristatus with desirability of 0.985. In conclusion, the results indicated that the formulations obtained in this present study justify the promising antioxidant properties of the polyherbal mixtures. Thus, it is sensible to use the combination of studied herbal formulation for development of any antioxidant supplement or food products in the future.The objective of this study is to determine the optimum antioxidant properties of polyherbal formulations of the aqueous extract of leaves of Strobilanthes crispus (pecah beling), Phyllanthus niruri (dukung anak), Orthosiphon aristatus (misai kucing) and Stevia rebudiana using in vitro method. There are 22 formulations consisting various proportions of the extracts designated using commercial statistical software package that is Design Expert 6.0.4. The antioxidant study of the individual extracts and their different combinations were conducted using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, Ferric Reduction Antioxidant Potential Assay (FRAP) and total phenolic content (TPC) assay. Results showed that O. aristatus has higher antioxidant properties in most of the assay when tested individually, as compared to S. crispus, P. niruri and S. rebudiana. Synergistic effect was exhibited in most of the polyherbal combinations. From the optimization process, it was revealed that the quadrat...

Modeling the rheological behavior of thermosonic extracted guava, pomelo, and soursop juice concentrates at different concentration and temperature using a new combination model

Abstract This study has modeled the rheological behavior of thermosonic extracted pink‐fleshed guava, pink‐fleshed pomelo, and soursop juice concentrates at different concentrations and temperatures. The effects of concentration on consistency coefficient (K) and flow behavior index (n) of the fruit juice concentrates was modeled using a master curve which utilized the concentration‐temperature shifting to allow a general prediction of rheological behaviors covering a wide concentration. For modeling the effects of temperature on K and n, the integration of two functions from the Arrhenius and logistic sigmoidal growth equations has provided a new model which gave better description of the properties. It also alleviated the problems of negative region when using the Arrhenius model alone. The fitted regression using this new model has improved coefficient of determination, R 2 values above 0.9792 as compared to using the Arrhenius and logistic sigmoidal models alone, which presented minimum R 2 of 0.6243 and 0.9440, respectively. Practical applications In general, juice concentrate is a better form of food for transportation, preservation, and ingredient. Models are necessary to predict the effects of processing factors such as concentration and temperature on the rheological behavior of juice concentrates. The modeling approach allows prediction of behaviors and determination of processing parameters. The master curve model introduced in this study simplifies and generalized rheological behavior of juice concentrates over a wide range of concentration when temperature factor is insignificant. The proposed new mathematical model from the combination of the Arrhenius and logistic sigmoidal growth models has improved and extended description of rheological properties of fruit juice concentrates. It also solved problems of negative values of consistency coefficient and flow behavior index prediction using existing model, the Arrhenius equation. These rheological data modeling provide good information for the juice processing and equipment manufacturing needs.

A Review of Malaysian Medicinal Plants with Potential Anti-Inflammatory Activity

This article aims to provide detailed information on Malaysian plants used for treating inflammation. An extensive search on electronic databases including PubMed, Google Scholar, Scopus, and ScienceDirect and conference papers was done to find relevant articles on anti-inflammatory activity of Malaysian medicinal plants. The keyword search terms used were “inflammation,” “Malaysia,” “medicinal plants,” “mechanisms,” “in vitro,” and “in vivo.” As a result, 96 articles on anti-inflammatory activity of Malaysian medicinal plants were found and further reviewed. Forty-six (46) plants (in vitro) and 30 plants (in vivo) have been identified to possess anti-inflammatory activity where two plants, Melicope ptelefolia (Tenggek burung) and Portulaca oleracea (Gelang pasir), were reported to have the strongest anti-inflammatory activity of more than 90% at a concentration of 250 µg/ml. It was showed that the activity was mainly due to the occurrence of diverse naturally occurring phytochemicals from diverse groups such as flavonoids, coumarins, alkaloids, steroids, benzophenone, triterpenoids, curcuminoids, and cinnamic acid. Hence, this current review is a detailed discussion on the potential of Malaysian medicinal plants as an anti-inflammatory agent from the previous studies. However, further investigation on the possible underlying mechanisms and isolation of active compounds still remains to be investigated.

Optimisation of microwave-assisted processing in production of pineapple jam

Pineapples are available all year round since they are unseasonal fruits. Due to the continuous harvesting of the fruit, the retailers and farmers had to find a solution such as the processing of pineapple into jam, to treat the unsuccessfully sold pineapples. The direct heating of pineapple puree during the production of pineapple jam can cause over degradation of quality of the fresh pineapple. Thus, this study aims to optimise the microwave-assisted processing conditions for producing pineapple jam which could reduce water activity and meets minimum requirement for pH and total soluble solids contents of fruit jam. The power and time of the microwave processing were chosen as the factors, while the water activity, pH and total soluble solids (TSS) content of the pineapple jam were determined as responses to be optimised. The microwave treatment on the pineapple jam was able to give significant effect on the water activity and TSS content of the pineapple jam. The optimum power and time for the microwav...

Identification of most tolerant lichen species to vehicular traffic’s pollutants at Batu Pahat area

Bio-indicators are organisms that can be used for the identification and qualitative determination of human generated environmental factors. The decreasing population of sensitive lichens in specific regions around the world due to low air quality level has make lichens as a bio-indicator for air pollution. Lichen is a result of symbiotic association of fungus and alga and well known for having wide variety of sensitivity towards environmental stressors such as air quality and climate change. The aim of this study is to identify the most tolerant lichen species to vehicular traffic’s pollutant at Batu Pahat urban and suburban areas. This study was conducted by using Index of Atmospheric Purity (IAP) method and followed by morphological and chemicals testing for species identification. Dirinaria picta has been identified as the most tolerant lichen species against pollutants from vehicle traffic. The results also indicated that the air quality of Batu Pahat town/urban area could be considered as moderately...