Wastewater from washed rice water as plant nutrient source: current understanding and knowledge gaps

A significant wastewater source in every household is washed rice water (WRW) because it contains leached nutrients (from washing the rice prior to cooking) that could be used as fertilizer. The paper reviewed the current understanding of the potential use of WRW as a plant nutrient source. WRW was shown to increase vegetables growth, such as water spinach, pak choy, lettuce, mustard, tomato, and eggplant. Different researchers have used various amounts of WRW, and their results followed a similar trend: the higher the amount of WRW, the higher the plant growth. WRW has also been used for other purposes, such as a source of carbon for microbial growth. WRW from brown rice and white rice had nutrients ranging from 40-150, 43-16306, 51-200, 8-3574, 36-1425, 27-212, and 32-560 mg L-1 of N, P, K, Ca, Mg, S, and vitamin B1 (thiamine), respectively. Proper utilization of WRW could reduce chemical fertilizer use and prevent both surface and groundwater contamination and environmental pollution. However, only a few of the studies have compared the use of WRW with the use of conventional NPK fertilizer. The major drawback of WRW studies is that they lack depth and scope, such as determining the initial and (or) final soil physico-chemical properties or plant nutrient contents. Considering the rich nutrient content in WRW, it will impact plant growth and soil fertility when used as both irrigation water and plant nutrient source. Therefore, it is recommended that studies on WRW effect on soil microbial population, plant, and soil nutrient contents to be carried out to ascertain the sustainability of WRW use as a plant nutrient source

Fermentation of washed rice water Increases beneficial plant bacterial population and nutrient concentrations

Washed rice water (WRW) is said to be a beneficial plant fertilizer because of its nutrient content. However, rigorous scientific studies to ascertain its efficiency are lacking. The purpose of this study was to determine the effect of fermenting WRW on the bacterial population and identification, and to measure how fermentation affects the nutrient composition of WRW. Rice grains were washed in a volumetric water-to-rice ratio of 3:1 and at a constant speed of 80 rpm for all treatments. The treatments were WRW fermented at 0 (unfermented), 3, 6, and 9 days. Bacterial N fixation and P and K solubilization abilities in the fermented WRW were assessed both qualitatively and quantitatively. The isolated bacterial strains and the WRW samples were also tested for catalase and indole acetic acid (IAA) production ability. Significantly greater N fixation, P and K solubilization, and IAA production were recorded after 3 days of fermentation compared with other fermentation periods, with increases of 46.9–83.3%, 48.2–84.1%, 73.7–83.6%, and 13.3–85.5%, respectively, in addition to the highest (2.12 × 108 CFU mL−1) total bacterial population. Twelve bacteria strains were isolated from the fermented WRW, and the gene identification showed the presence of beneficial bacteria Bacillus velezensis, Enterobacter spp., Pantoea agglomerans, Klebsiella pneumoniae and Stenotrophomonas maltophilia at the different fermentation periods. All the identified microbes (except Enterobacter sp. Strain WRW-7) were positive for catalase production. Similarly, all the microbes could produce IAA, with Enterobacter spp. strain WRW-10 recording the highest IAA of up to 73.7% higher than other strains. Generally, with increasing fermentation periods, the nutrients N, S, P, K, Mg, NH+4, and NO−3 increased, while pH, C, and Cu decreased. Therefore, fermentation of WRW can potentially increase plant growth and enhance soil health because of WRW’s nutrients and microbial promotional effect, particularly after 3 days of fermentation

Health System for Dengue Control in Singapore

Dengue fever/dengue haemorrhagic fever (DF/DHF) first appeared in Singapore in an outbreak in 1960. In 1966, the Ministry of Health established the Vector Control Unit which was charged with the responsibility of controlling the dengue vector mosquitoes, Aedes aegypti and Aedes albopictus. The Unit immediately launched an Aedes control programme based on source reduction and public health education. To obtain reliable statistics on disease incidence, DF/DHF was made administratively notifiable in 1966, and finally, legally notifiable in 1977. It was also recognized early in the control programme that long-term and active participation by the community was essential for its implementation. A new legislation called the Destruction of Disease-Bearing Insects Act was thus enacted in 1968. The Act empowers vector control officers to enter and examine houses for mosquito breeding, to take appropriate control measures, and to serve offenders with orders and summonses which carry a fine or imprisonment by the court. With the new legislation in force, the Aedes control programme adopted an integrated approach of source reduction, public health education and law enforcement. When the new Ministry of the Environment was formed in 1972 to take over the responsibility of environmental health, its Vector Control and Research Department and the Quarantine & Epidemiology Department became responsible for the surveillance and control of DF/DHF in the country. Surveillance of disease incidence and Aedes vectors is important in the prevention and control of DF/DHF outbreaks. Disease surveillance is conducted by officers of the Quarantine & Epidemiology Department based on notifications on clinically diagnosed cases as well as on the number of blood specimens submitted by hospitals, clinics, and private practitioners to the Virology Division of the Department of Pathology in the Ministry of Health and the Department of Microbiology of the National University of Singapore for laboratory confirmation of dengue infection. Aedes surveillance depends on regular surveys of mosquito larvae and adults in designated DF/DHF-sensitive areas. In addition to destruction of breeding habitats, fogging is carried out when the Aedes house index is 2% and above, or when a potential outbreak situation arises such as the occurrence of a focus of two or more DF/DHF cases in an area

Epidemiology of Dengue in Singapore-Current Situation

There has been a resurgence of dengue fever/dengue haemorrhagic fever (DF/DHF) cases in Singapore in recent years. Following the large outreak in 1973 with 1,187 cases and 27 deaths, the incidence of DF/DHF declined with minor bi-annual outbreaks occurring in 1978, 1980 and 1982. Beginning from 1986, however, the DF/DHF situation changed for the worse when outbreaks of increasing size occurred almost annually. In the past 3 years, there were 1,733 cases in 1990, 2,179 cases in 1991 and 2,878 cases in 1992. In the 1991 and 1992 outbreaks, 93-95% of the notified cases required hospitalization and 92-95% of them were serologically confirmed by the IgM capture ELISA and/or the commercial Dengue Blot assay. The number of fatal cases, however, remained low with 3-6 reported deaths in the three outbreaks. All age groups were affected with the highest morbidity rate in children and young adults between 15 and 24 years of age. In contrast, in the earlier 1973 and 1978 outbreaks, more patients below the age of 15 years were observed. There was a slight predominance among males and Chinese had the highest morbidity rate compared with Malays and Indians. The recent outbreaks occurred mainly in highly populated urban and suburban areas in the eastern, northeastern and southeastern parts of the island. Patients living in landed property such as compound houses had a 9X higher morbidity rate than those living in high-rise flats. Cases were reported throughout the year and the number increased during May and June. The increased DF/DHF incidence was preceded by an increase in the Aedes mosquito population. In the 1991 and 1992 outbreaks, although the overall Aedes house index was<1 for both Ae aegypti and Ae albopictus higher indices were detected in localized areas with high dengue transmission. The proportion of compound houses found breeding Ae aegypti was 3-4 times and Ae albopictus 7-10 times higher than that of flats. The major breeding habitats were ornamental and domestic containers and discarded receptacles

Compositional and thermal characteristics of palm olein-based diacylglycerol in blends with palm super olein

Palm olein-based diacylglycerol (POL-DAG) was blended with palm super olein (POoo) in various concentrations (10–90%), with increments of 10% (wt/wt) POL-DAG. The physical and chemical characteristics, i.e., iodine value, acylglycerol content, fatty acid composition, melting and crystallization profiles and solid fat content, for POL-DAG, POoo and their binary blends were evaluated. The mid-infrared FTIR was used to determine the absorption bands of the different concentrations of the oil blends. Only slight differences of FAC and IV were observed. POL-DAG:POoo blends showed significant changes (p < 0.05) in DAG content and decreases in TAG content with increasing POL-DAG content. The DSC thermograms showed that the addition of different concentrations of POL-DAG changed the melting and crystallization behavior of the oil blends (POL-DAG:POoo). The crystallization onset point increased (p < 0.05) with an increasing POL-DAG concentration (10–90%). POL-DAG has the same absorption bands as POoo, with the exception of several minor peaks that appeared at (I) 2954 cm− 1, (II) 1267 cm− 1, (III) 1199 cm− 1, (IV) 1222 cm− 1 and (V) 966 cm− 1. This study will provide essential information for the palm oil industry to identify the most suitable POL-DAG blends with desirable physicochemical properties for food application purposes

Dengue virus type 1 clade replacement in recurring homotypic outbreaks

BACKGROUND: Recurring dengue outbreaks occur in cyclical pattern in most endemic countries. The recurrences of dengue virus (DENV) infection predispose the population to increased risk of contracting the severe forms of dengue. Understanding the DENV evolutionary mechanism underlying the recurring dengue outbreaks has important implications for epidemic prediction and disease control. RESULTS: We used a set of viral envelope (E) gene to reconstruct the phylogeny of DENV-1 isolated between the periods of 1987–2011 in Malaysia. Phylogenetic analysis of DENV-1 E gene revealed that genotype I virus clade replacements were associated with the cyclical pattern of major DENV-1 outbreaks in Malaysia. A total of 9 non-conservative amino acid substitutions in the DENV-1 E gene consensus were identified; 4 in domain I, 3 in domain II and 2 in domain III. Selection pressure analyses did not reveal any positively selected codon site within the full length E gene sequences (1485 nt, 495 codons). A total of 183 (mean dN/dS = 0.0413) negatively selected sites were found within the Malaysian isolates; neither positive nor negative selection was noted for the remaining 312 codons. All the viruses were cross-neutralized by the respective patient sera suggesting no strong support for immunological advantage of any of the amino acid substitutions. CONCLUSION: DENV-1 clade replacement is associated with recurrences of major DENV-1 outbreaks in Malaysia. Our findings are consistent with those of other studies that the DENV-1 clade replacement is a stochastic event independent of positive selection

Iodine deficiency disorders among pregnant women in Sarawak, Malaysia

Introduction Iodine deficiency disorders (IDD) during pregnancy may impair the neurological development of the fetus. The aim of this study is to determine the iodine status among pregnant women (PW) in Sarawak after introduction of mandatory universal salt iodisation (USI) for seven years. Methods A total of 508 first trimester PW attending government Maternal and Child Health Care clinics in all 11 divisions in Sarawak between 1st April and 15th June 2015 were recruited. Urine samples were obtained and analysed for urinary iodine concentration (UIC) using the modified Sandell-Kolthoff reaction method. For pregnant women, an adequate iodine intake was defined as a median UIC between 150-249 μg/L according to the WHO/UNICEF/ICCIDD’s criterion. For further analyses, the 11 divisions were then combined into 3 regions, namely Northern (Miri, Bintulu, Limbang), Central (Kapit, Mukah, Sibu, Sarikei, Betong) and Southern (Kota Samarahan, Kuching, Sri Aman). Results The median UIC of the PW in Sarawak was 105.6 μg/L, indicating iodine deficiency. A total of 330 (65.0%) PW had UIC<150 μg/L. In terms of urinary iodine levels by region, the median UIC in Northern, Central and Southern regions were 136.3 μg/L, 85.5 μg/L and 97.4 μg/L respectively. The differences in median UIC between regions were significant. In addition, the Northern region (p = 0.001), Malay/Melanau ethnicity (p = 0.015) and parous parity (p = 0.014) were significantly associated with higher median UIC. No significant association was found for locality, age nor gravida. Conclusions This study indicates inadequate iodine status among PW in Sarawak despite seven years of mandatory USI. In fact, the majority of PW appear not to be protected against IDD and its consequences. In future, a comprehensive study should be carried out to determine the levels of iodine in salt at the retail outlets, villages and households in Sarawak

16S metagenomic microbial composition analysis of kefir grain using MEGAN and BaseSpace

Kefir is a unique cultured product traditionally made from the fermentation of milk with kefir grains. Metagenomics analysis of kefir grain is essential to understand the composition of microbial populations in the kefir grain. Many microbial populations have been reported in kefir grains from different parts of the world. Although the kefir from Malaysian kefir grain is regularly consumed locally, no report has been made on the kefir grain microbial profile. The present study used kefir grain obtained locally and the microbial composition in the kefir grain was determined using Next Generation Sequencing (NGS). The taxonomic results analysis obtained when using BaseSpace (Illumina) and MEGAN were compared. The software agreed that Lactobacillus genus dominated the samples and the predominant species was L. kefiranofaciens (81.45–91.93%) while L. kefiri (2.01–2.47%) was the second in abundance. The results suggested that Malaysian kefir grain contained the same top two predominant species using both software methods and the microbial composition between both software did not vary significantly

A reverse transcription loop-mediated isothermal amplification for broad coverage detection of Asian and African Zika virus lineages.

BACKGROUND: Early detection of Zika virus (ZIKV) infection during the viremia and viruria facilitates proper patient management and mosquito control measurement to prevent disease spread. Therefore, a cost-effective nucleic acid detection method for the diagnosis of ZIKV infection, especially in resource-deficient settings, is highly required. METHODS: In the present study, a single-tube reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for the detection of both the Asian and African-lineage ZIKV. The detection limit, strain coverage and cross-reactivity of the ZIKV RT-LAMP assay was evaluated. The sensitivity and specificity of the RT-LAMP were also evaluated using a total of 24 simulated clinical samples. The ZIKV quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay was used as the reference assay. RESULTS: The detection limit of the RT-LAMP assay was 3.73 ZIKV RNA copies (probit analysis, P ≤ 0.05). The RT-LAMP assay detected the ZIKV genomes of both the Asian and African lineages without cross-reacting with other arthropod-borne viruses. The sensitivity and specificity of the RT-LAMP assay were 90% (95% CI = 59.6-98.2) and 100% (95% CI = 78.5-100.0), respectively. The RT-LAMP assay detected ZIKV genome in 9 of 24 (37.5%) of the simulated clinical samples compared to 10 of 24 (41.7%) by qRT-PCR assay with a high level of concordance (κ = 0.913, P < 0.001). CONCLUSION: The RT-LAMP assay is applicable for the broad coverage detection of both the Asian and African ZIKV strains in resource-deficient settings

Antioxidant and hepatoprotective effects of the food seasoning curry leaves Murraya koenigii (L.) Spreng. (Rutaceae)

Murraya koenigii (L.) Spreng. (Rutaceae), a common spice, has been traditionally used to reduce inflammation and hepatitis. The present study aimed to reveal the antioxidant and anti-inflammatory activity as well as the regulation of cytochrome P450 levels elicited by aqueous extracts of M. koenigii leaves in response to paracetamol-induced liver toxicity in BALB/c mice. Liver toxicity was induced by an overdose of paracetamol followed by treatment with a M. koenigii leaf aqueous extract. The levels of serum liver markers, liver antioxidants, inflammatory markers and liver cytochrome P450 2E1 were quantified after 14 days of treatment. Histopathological analysis of the liver was also carried out. In vitro antioxidant levels and phenolic acid characterization were also performed. The extracts (50 and 200 mg kg-1 body weight) effectively restored the serum liver profiles (alanine transaminase, aspartate transaminase and alkaline phosphatase), liver antioxidant levels (superoxide dismutase, glutathione and ferric reducing ability of plasma) and inflammatory markers (tumor necrosis factor alpha, inducible nitric oxide synthase, nuclear factor kappa-light-chain-enhancer of activated B cells and nitric oxide) to healthy levels in a dosage dependent manner. The level of liver cytochrome P450 2E1 was also lowered in the extract treated groups. Histopathological assessment showed that treatment with 200 mg kg-1 of the M. koenigii aqueous extract was able to reduce liver necrosis in mice fed paracetamol. Gallic acid concentration was the highest among all the phenolic acids detected in the extract. These results suggested that the M. koenigii aqueous extract, which possessed antioxidant and anti-inflammatory effects, can be used as a potential treatment for liver diseases caused by oxidative stress