Explore the vast range of titles available.

Pectinases are the group of enzymes that catalyze the degradation of pectic substances. It has wide applications in food industries for the production and clarification of wines and juices. The aim of this study was to isolate, screen and characterize pectinase from fungi isolated from various soil samples and evaluate its application in juice clarification. Fungal strains were isolated and screened primarily using 1% citruspectin incorporated potato dextrose agar (PDA) and secondarily using pectinase screening agar medium (PSAM) for pectinolytic organisms. The enzyme was produced by submerged state fermentation and assayed using the dinitro salicylic acid (DNS) method. From 20 different soil samples, 55 fungal isolates were screened primarily and, among them, only 14 isolates were subjected for secondary screening. Out of 14, only four strains showed the highest pectinolytic activity. Among four strains, Aspergillus spp. Gm showed the highest enzyme production at a 48-h incubation period, 1% substrate concentration, and 30 °C temperature. The thermal stability assessment resulted that the activity of pectinase enzyme declines by 50% within 10 min of heating at 60 °C. The optimum temperature, pH, and substrate concentration for the activity of enzyme was 30 °C (75.4 U/mL), 5.8 (72.3 U/mL), and 0.5% (112.0 U/mL), respectively. Furthermore, the yield of the orange juice, the total soluble solid (TSS), and clarity (% transmittance) was increased as the concentration of the pectinase increased, indicating its potential use in juice processing. Overall, the strain Aspergillus spp. Gm was identified as a potent strain for pectinase production in commercial scale.

A study was undertaken to assess the quality of groundwaters in the Kathmandu Valley, Nepal. The groundwater samples were randomly collected from shallow well, tube well, and deep-tube wells located at different places of Kathmandu, Lalitpur, and Bhaktapur districts in the Kathmandu valley. Physical, chemical, and microbiological parameters of the samples were evaluated to estimate the groundwater quality for drinking water. It was found that the groundwater in the valley is vulnerable to drink due to presence of iron and coliform bacteria. Iron was estimated to be much higher then the acceptable limit of World Health Organization (WHO) drinking-water quality guidelines (1.9 mg/L). Total coliform bacteria enumerated in groundwaters significantly exceeded the drinking-water quality standard and observed maximum coliform (267 CFU/100 mL) in shallow wells. The electrical conductivity and turbidity were found to be 875 μS/cm and 55 NTU, respectively, which are above the WHO recommendations for drinking water guidelines. However, pH value was measured within the acceptable limit. Arsenic, chloride, fluoride, and hardness concentrations were found to be in agreement with the recommendations of WHO drinking-water quality guidelines.

Coffee pulp, mucilage, and beans with mucilage were used to develop alcoholic beverages. The pulp of 45.3% pulp, 54.7% mucilage with seed, and 9.4% mucilage only were obtained during the wet processing of coffee. Musts were prepared for all to TSS (Total soluble solid) 18 °Bx and fermentation was carried out for 12–16 days until TSS decreased to 5 °Bx at 30 °C. Phenolic characteristics, chromatic structures, chemical parameters, and sensory characteristics were analyzed for the prepared alcoholic beverages. Methanol content, ester content, aldehyde, alcohol, total acidity, caffeine, polyphenols, flavonoids, chromatic structure, and hue of the alcoholic beverage from the pulp was 335 mg/L, 70.58 ppm, 9.15 ppm, 8.86 ABV%, 0.41%, 30.94 ppm, 845.7 mg GAE/g dry extract, 440.7 mg QE/g dry extract, 0.41, and 1.71, respectively. An alcoholic beverage from the pulp was found superior to an alcoholic beverage from mucilage with beans and a beverage from mucilage in sensory analysis. There is the possibility of developing fermented alcoholic beverages from coffee pulp and mucilage. However, further research is necessary for quality of the beans that were obtained from the fermentation with the mucilage.

This study was undertaken to analyse processed bottled water for drinking water quality. Altogether 50 water samples of different brands were randomly collected from public places in Kathmandu valley. The samples were analysed for physical (turbidity, pH and electrical conductivity), chemical (iron, manganese, arsenic, cadmium, chromium, lead, ammonia, fluoride, chloride, sulphate, copper, total hardness, calcium, mercury and aluminum) and microbiological (fecal coliform and total coliform) parameters. The results revealed that >300 CFU/100 mL of Escherichia coli (E. coli) (fecal coliform) and total coliform (TC) bacteria were counted in 76 and 92% samples, respectively. The bacterial population was beyond the limit of the Department of Food Technology and Quality Control (DFTQC) (0 CFU/100 mL of water). Chemical parameters analysed for fluoride (0.5–1.5 mg/L) and ammonia (1.5 mg/L) exceeded the DFTQC values. The range of fluoride estimated was 0.001–2.37 mg/L and the maximum concentration of ammonia was 4.66 mg/L. Most of the processed water crossed the threshold standard of E. coli and TC bacteria and may pose a risk if used for drinking purposes. Therefore, to minimize the public health risk of contaminated water, scientific methods and standards of purification should be followed during the process, production, storage, and delivery of processed water.

Contamination of the trace elements (TEs) in the freshwater ecosystems is becoming a worldwide problem. This study was carried out to investigate the TEs contamination, and their associated health risk in Begnas Lake and Rupa Lake, Gandaki Province, Nepal. A total of 30 water samples were collected from both lakes during the pre-monsoon season in 2016. The samples were analyzed for the TEs including copper (Cu), lead (Pb), zinc (Zn), nickel (Ni), cobalt (Co), chromium (Cr), cadmium (Cd), manganese (Mn), cesium (Cs), and arsenic (As) using inductively coupled plasma mass spectrometry. The results exhibited that the mean concentrations of all the TEs were higher in Rupa Lake as compared to Begnas Lake except Pb. Principal component analysis and cluster analysis revealed that both the geogenic and anthropic sources were the major contributors of TEs in the lake water. Anthropic activities were considered to contribute the TEs like Zn and Mn in lake water mainly via agricultural runoff, while evaluating the risk of TEs on human health all the elements showed HQ < 1 and CR < 10 −4 indicating currently very low health risk concerns. In good agreement with above, the water quality index (WQI) of the Begnas Lake and Rupa Lake was 2.67 and 5.66, respectively, specifying the lake water was safe for drinking and public health concern. This appraisal would help the policymakers and concerned stakeholders for the sustainable management of Ramsar listed freshwater lakes in the Himalayas.

Soil salinity is considered crucial for seed germination, seedling growth, and crop production in arid and semi-arid regions. Seed priming can be an effective solution to improve maize germination and growth, under salinity stress. An experiment was conducted to study the effect of seed priming with NaCl and salinity stress on germination and growth of maize variety Arun-2. Before sowing, eighty maize seeds were soaked in 5g/L aqueous NaCl solution for 12 hours at 27-degree Celsius. Primed and unprimed seeds were sown in 10-liter capacity plastic pots and watered with 200mL of 0, 2, 4, 6, and 8 g/L saline solutions at two days intervals. Germination percentage, shoot length, and number of leaves per plant were measured to access the germination and growth parameters. The results showed that priming seeds with NaCl solution significantly (P<0.05) improved the germination of maize seeds. Whereas, germination of Arun-2 was not significantly affected by salinity stress. Salinity has negative impacts on shoot length and number of leaves. The shoot length at 38 DAS was found to be the longest at salinity level 0 mg/L (8.61cm) and it was found to be shortest at highest salinity level i.e. 8 mg/L (3.12 cm). Increasing salt stress has severe effects on the growth of maize, both during the seedling and vegetative growth stages of the plant. Seed priming alleviated the inhibitory effect of salt stress on germination and seedling growth of maize. Thus, seed priming with 5 g/L NaCl solution could be useful to improve the germination and growth of maize under saline stress conditions.

Present study was undertaken to analyze drinking water quality of Kathmandu valley with the estimation of essential minerals of public health concern. Twenty water samples of each source, viz. public water supply, private water supply, and processed drinking water supply, were randomly collected. Sample analysis was carried out for physical (temperature, pH, and electrical conductivity), chemical (calcium, magnesium, sodium, and potassium), and microbiological (total coliform—TC) parameters. It was found that the physical parameters such as temperature, pH, and electrical conductivity (EC) were within the World Health Organization (WHO) drinking water quality guidelines. Generally, for all the water sources the average concentration of calcium was below the WHO drinking water quality guidelines as well as DRI (Dietary Reference Index) recommendations. Moreover, the concentration of magnesium, sodium, and potassium was also found below the DRI recommendations for all the water sources. Microbiological parameter enumerated for TC in processed drinking water depicted bacterial population from 0 CFU/100 mL to 46 CFU/100 mL. The presence of TC in processed drinking water makes the water unacceptable for drinking purpose, although the physical parameters were almost within the WHO drinking water quality guidelines. The presence of required amount of minerals plays a critical role in maintaining human health system and vitality. Therefore, this study explores the quality of drinking water in the Kathmandu valley in terms of minerals and TC bacteria.

A total of 100 fresh-raw vegetable samples were collected from the Kathmandu, Lalitpur and Bhaktapur districts of Nepal to evaluate microbial and parasitic contamination, presence of Extended Spectrum Beta Lactamase (ESBL)-producing Escherichia coli and detect the blaTEM and blaCTX-M genes among the Escherichia coli isolates. This study revealed that the prevalence of Giardia cysts was highest (100%) and Hookworm and Entamoeba coli were lowest (1% each). Coliforms were isolated from every raw vegetable sample. A total of 178 bacterial isolates were isolated among which 57 isolates were identified as E. coli, out of which 33 were Multi-drug resistant (MDR) isolates. The high rate of resistance was found towards amoxicillin/clavulanate, tetracycline and cotrimoxazole. The 10 E. coli isolates tested positive in an ESBL screening, out of which 4 were confirmed as ESBL producers by a combined disc test. Out of these 4 confirmed ESBL E. coli, one was found to carry both the blaTEM gene and blaCTX-M genes by the Polymerase Chain Reaction (PCR) technique. One isolate has only the blaTEM gene, while other isolate harboured only blaCTX-M genes.

The government of Nepal has recommended blanket fertilizer application for rice cultivation, which results in lower nutrient use efficiency (NUE) particularly under rainfed conditions. With the aim of finding an appropriate nutrient management practices concerning rice production and profitability, a field experiment was conducted during rainy season of 2017 and 2018 at Kavrepalanchowk and Dang district of Nepal. Altogether, five treatments comprising various nutrient management practices viz. Nutrient Expert Model (NE), use of Leaf Color Chart (LCC), Government Recommended Fertilizer Dose (GON), Farm Yard Manure (FYM), and Farmers’ Field Practice (FFP), were laid out in RCBD with four replications in farmers’ fields. The analysis of variance showed significant difference between treatments for test weight and grain yield in Kavrepalanchowk whereas all traits except number of effective tillers were significant in Dang. The significantly higher grain yield and harvest index were obtained in NE, followed by LCC; and the overall straw yield was highest in LCC, followed by NE in both the locations. Also, yield gap analysis suggested the NE had 44.44% and 23.97% increase in yield as compared to FPP in Kavrepalanchowk and Dang, respectively. The combined analysis with Best Linear Unbiased Estimator revealed the interaction of nutrient management and location significantly effects the straw yield and harvest index across both the locations. The estimated mean straw yield and harvest index were 10.93 t/ha and 34.98%, respectively. Both correlation study and biplot of principal component analysis signaled grain yield had positive correlation with all other traits. Furthermore, the net revenue was maximum for NE, followed by LCC in both the locations. The benefit: cost ratio was highest for NE which was 1.55 in Kavrepalanchowk and 2.61 in Dang. On the basis of these findings, NE and LCC can be effectively used as nutrient management practice by the farmers to obtain maximum production and profitability in Rice.

Poor waste management in the Kathmandu valley has deteriorated the water quality of surface and groundwater sources. The objective of this study was to assess the status of water quality (WQ) in drinking water sources of groundwater and municipal supply (tap water) from the Bagmati river basin in Kathmandu valley. A total of 52 water samples from deep tube-well, tube-well, dug-well, and tap water were collected and analyzed for physical, chemical, and microbiological parameters using standard methods. The results revealed that chloride, total hardness (TH), copper, nitrate, sulfate, and turbidity were within the recommendations of the National Drinking Water Quality Standard (NDWQS). Total coliform (TC) bacteria in 84.6% of the samples exceeded drinking water guidelines. Similarly, the isolates of different enteric bacteria, namely Escherichia coli (21.5%), Citrobacter spp. (20.9%), Klebsiella spp. (19.8%), Proteus spp. (13.9%), Enterobacter spp. (8.72%), Salmonella spp. (5.8%), Shigella spp. (5.2%), and Pseudomonas (4.1%) were identified in the samples collected from the respective sources. Out of the 52 water samples, 7.7% of samples had fecal contamination of somatic coliphage. The groundwater and municipal water supply in the study area are not safe for drinking purposes. Treatment of water is required before its use for household applications.