bluuebunny/crossref_metadata_2025 huggingface dataset:
Antioxidant activity, total phenolics and flavonoids contents of Pandanus amaryllifolius (Roxb.)
Authors: Quyen N T C , Quyen N T N , Nhan L T H , Toan T Q
Published: December 2020

Pandanus amaryllifolius Roxb. was commonly used in Vietnam as a fragrance because of its aroma. These aromatic plants are the primary source of medicinal herbs because of their valuable biological activities. This study was aimed at determining the phytochemical content, Total flavonoids contents (TFC), total phenolic content (TPC) and antioxidants were analyzed by Folin-Ciocalteu and DPPH scavenging assays, respectively. The total flavonoid content is measured by the aluminum chloride method. The qualitative phytochemical analysis confirmed the presence of flavonoids, terpenoids, coumarin, and reducing sugar, which is chemical components in Pandanus amaryllifolius Roxb extract. Results showed that ethanol extract exhibited higher DPPH (129.327 ug/ml) and TPC (38.12 mgGAE/DW) activity than water extraction (265.738 ug/ml and 10.97 mgGAE/DW). Research shows that using this plant more in pharmaceuticals or food should be focused and developed.
Phytochemical screening of Allium Tuberosum Rottler. ex Spreng as food spice
Authors: Nhut P T , An T N T , Minh L V , Truc T T , Anh N H T
Published: December 2020

In Vietnam, Allium Tuberosum Rottler. ex Spreng (ATRES) was used in everyday meals as a seasoning, and as a common remedy for the prevention of diarrhea, asthma, and so on. In this study, We evaluated the phytochemical composition, total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of ATRES, which was harverted in Vietnam. The findings indicate that Vietnamese ATRES had a varied range of pharmacologically active compounds, including alkaloid, flavonoid, terpenoid, tannin, coumarin, saponin, and reduced sugar. Folin-Ciocalteu calculates the TPC and the TFC is derived using the aluminum chloride method. The TPC and TFC of ethanol extract in ATRES achieved 46.15 ± 1.26 mgGAE/g DW and 31.10 ± 1.12 mg QE/g DW, respectively. Taken together, we found that the antioxidant capacity in DPPH forms (2, 2-diphenyl-1-picrylhydrazyl) was assessed by spectrophotometric method and obtained an IC50 result of 97.46 µg/ml. These results indicate that Vietnamese ATRES is effective in increasing food use with its antioxidant and valuable activity.
Phytochemical Content and Antioxidant activity in aqueous and ethanolic extracts of Eryngium foetidum L.
Authors: Thi N Q N , An T N T , Nguyen O B , Dung L T , Minh L V , Nhan L T H
Published: December 2020

Eryngium foetidum L. has been used as a spice for food and treatment for diabetes, rheumatism, anti-inflammatories, respiratory and stomach disorders. In Vietnam, due to high consumption of Eryngium foetidum L. in popular dishes and its significant benefits, the preliminary screening of the plant phytochemicals is required to extend its application and improve efficacy. The present research aimed at Eryngium foetidum L. extraction using aqueous and ethanolic as solvents to explore their phytochemical composition, total contents of flavonoids and phenolics and antioxidant activity. Phytochemical screening has detected the presence of flavonoids, tannins, alkaloids and terpenoids in both plant extracts. In addition, the total content of phenolics in both extract was equally significant while the total content of flavonoids was higher in ethanolic extract, as compared to the aquaeous extract. The antioxidant actions of aquaeous and ethanolic extracts were estimated using DPPH and ABTS scavenging assays. Results have shown that the former exhibited stronger DPPH scavenging activity than the latter. Findings from the present study suggested that ethanol and water can be useful for Eryngium foetidum L. extraction with high content of phytochemicals, phenolics and antioxidant activity.
Bioactive Compounds and Antioxidant Activity of Leaves from Piper sarmentosum Piperaceae
Authors: Nguyen N Q , Nguyen V T , Van N T H , Vo T N M
Published: December 2020

Piper sarmentosum belongs to Piperaceae family, which is used as a cuisine in many Southeast Asian. This is a valuable herbal plant used as a traditional treatment for headaches, coughs, asthma, fever and as a spice in everyday cooking. The plant plays an important role in the antioxidant application. This study was conducted to analyze qualitative phytochemicals and assess the free radical potential, total polyphenol and flavonoid content of Piper sarmentosum leaves extracts. Using the standard procedure, the crude extracts were proved having lots phytochemicals such as alkaloids, coumarin, flavonoids, reducing compounds, saponins, tannins and terpenoids. The ethanolic extract from leaves of Piper
sarmentosum had a medium total polyphenols content (60.61 ± 0.96 µgGAE/mg) and flavonoid content (70.14 ± 0.38 µgQE/mg). DPPH and ABTS radical scavenging activity increased proportionally with the concentration of Piper
sarmentosum. IC50 value of ethanolic extract were 264.20 ± 17.90 μg/mL (DPPH) and 176.40 ± 8.62 μg/mL (ABTS), respectively. The leaves of Piper sarmentosum can be used in the battle against diseases induced by free radicals such as asthma, diabetes mellitus, and coronary artery disease as a natural supply of antioxidants.
Phytochemical Screening, Antioxidant Activities, Total Phenolics and Flavonoids content of Leaves from Persicaria
odorata Polygonaceae
Authors: Nguyen V T , Nguyen M T , Nguyen N Q , Truc T T
Published: December 2020

Persicaria
odorata Polygonaceae is a widely used herb in Asia. It contains several interesting bioactive components, and possesses properties that promote health. This is an important medicinal plant used to treat inflammation and swelling, diarrhea and excessive bleeding, and so on. Base on phytochemical analysis, the Persicaria
odorata leaves contained lots compounds such as alkaloids, tannins, anthraquinone, flavonoids, terpenoids, coumarins, saponins and reducing compounds. The presence of those phytochemicals in this herbs indicated its potential medicinal effects, along with various vital biological and physiological properties. The leaves were extracted using ethanol and water to produce the respective extracts. The total phenolic and flavonoids content of each extract were determined by the Folin-Ciocalteu method and the aluminum chloride reagent, respectively. The ethanolic extract from leaves of Persicaria
odorata showed higher total phenolic (58.56 ± 3.86 µgGAE/mg) and flavonoid contents (70.65 ± 4.14 µgQE/mg) than the aqueous extract. The percentage of radical scavenging activity was determined using radical scavenging assay with DPPH and ABTS. The ethanol extract of Persicaria
odorata leaves had a high antioxidant activity with an IC50 of 311.26 ± 3.06 µg/mL DPPH and 167.66 ± 6.67 ABTS. The presence study showed that in ethanolic and aqueous extracts the medicinal potential of Persicaria odorata leaves and the positive relation between the total content of polyphenols and antioxidant activities.
Effect of Wet Milling and Purification Process on Yield and Color of Jackfruit Seed Starch
Authors: Thanh V T , Khang V C , Nhan N P T , Nguyen D T , Nhi T T B , Quoc N T
Published: December 2020

Jackfruit is a common fruit, which grows in Asian areas, including Thailand, India, China and Vietnam. Jackfruit seeds are a by-product of the food industry, and are typically ignored as a source of nutrients in the human diet given their possible application.. Starch production is a conventional ways to take advantage of this by-product source. The wet milling and purification process are the two main processes for extracting and improving the color of starch. Therefore, this research aims to determine the impact of wet milling and purification process on yield and color of starch as well as evaluate some parameters of physicochemical properties in jackfruit seed starch. In this study, the ratio of jackfruit seed:water (1:1, 1:2, 1:3, 1:4 and 1:5) and the time of wet milling (1, 2, 3, 4 and 5 min) are investigated. Three main factors observed in the purification process were the type of solvent (water and ethanol), solvent ratio (1:2, 1:4, 1:6 and 1:8) and the number of purification (1, 2, 3, 4 and 5 times). The result revealed that the ratio of jackfruit seed : water reached the highest starch yield was 1:3 (32.11±1.06%, db) and the time achieved 3 min (40.77±1.25%, db). The selected solvent for purification of starch was ethanol with the ratio of sample : water was 1:4 and the number of purification was two times for the best color. Some of characteristic nutrition values was evaluated, including %protein: 3.8, %ash: 0.08, %carbohydrate 86.99 and %lipid 0.20). The water solubility index and viscosity of starch were contradictory. When the temperature increased, the viscosity of starch decreased but the solubility index increased. Jackfruit seed starch was spherical or semi-oval which was presented by SEM (Scanning Electron Microscope) method.
The influence of drying temperature on the quality, morphology and drying characteristics of Cosmos caudatus
Authors: Latiff N A , Abdullah L C , Ong P Y , Embi K , Malek S A
Published: December 2020

This study scrutinizes the influence of oven drying temperature (40, 60, and 80 °C) on the product quality (phenolic content and antioxidant activity), morphological appearance, and drying characteristics ofCosmos caudatus (C. caudatus).A spectroscopic UV assay and a Field emission scanning electron microscope (FESEM) were used to analyse the product quality and the morphological appearance of theC. caudatusleaves. The drying characteristics were assessed based on the pattern from the drying curve (moisture ratio versus drying time) at the tested temperatures. It was observed that a drying temperature of 40 °C preserved the quality of the driedC. caudatusleaves. This may be seen where a significant reduction of the phenolic content and antioxidant activity occurred at 60 to 80 °C, probably due to the decomposition of the valuable phytochemical compounds. This effect correlated with the physical damage that took place to the vegetal tissues. The damage was recorded as 40 < 60 < 80 °C according to the severity (from minor to severe damage). The drying process ofC. caudatusoccurred mainly in the falling rate period, in the absence of an initial rate period. Higher drying temperatures resulted in a shorter drying time as proven by the value of the effective moisture diffusivity that increased from 4.12 × 10−12m2/s (40 °C) to 24.71 × 10−12m2/s (80 °C). TheC. caudatussample dried with an oven dryer at 40 °C possessed the best condition of drying without compromising the quality of the driedC. caudatusleaves.
Effect of encapsulation agents on antioxidant activity and moisture content of spray dried powder from Mahkota Dewa fruit extract
Authors: Kathiman M N , Abdul Mudalip S K , Gimbun J
Published: December 2020

Mahkota Dewa is rich in bioactive compounds including mangiferin, saponin and polyphenols. This work aims to investigate the encapsulation of Mahkota Dewa by spray drying using different types of encapsulation agent. A subcritical water extraction process was used to extract the bioactive compounds from dried Mahkota Dewa prior to spray drying process. The encapsulation agents used were maltodextrin (MT), arabic gum (AG) and mixture of arabic gum-maltodextrin (AG-MT). The spray drying conditions namely inlet dry air temperatures, dry air flow rate and inlet feed flowrate were 200°C, 3.7 m/s and 485 mL/h, respectively. The spray dried powder samples were evaluated for antioxidant activity and moisture content and compared with those without encapsulation agent. A high value of antioxidant activity and low moisture content were observed for samples with encapsulation agents. Result suggested the maltodextrin produced particles with the lowest moisture content (4.84 %) and highest antioxidant activity (94.22%), thus can be recommended as the most suitable encapsulation agent in this work.
Production of edible fungal (Rhizopus delemar CBS 145940) biomass from organosolv-pretreated oil palm empty fruit bunch (OPEFB) in submerged fermentation
Authors: Marhendraswari MB D , Mondylaksita K , Millati R , Budhijanto W , Ferreira J A , Niklasson C , Taherzadeh M J
Published: December 2020

Accumulation of oil palm empty fruit bunches (OPEFB) from palm oil industry poses challenges for the disposal process, which leads to environmental damage. For this reason, valorization of OPEFB fractions to produce edible fungal biomass was carried out in this research. The fungus wasRhizopus delemarCBS 145940, which is an edible fungus, Indonesian indigenous, and is favorable for the production of several end products. Organosolv pretreatment was first conducted on OPEFB using ethanol (50%) as the solvent. Enzymatic hydrolysis was then performed using Cellic® Ctec3 on the pretreated-OPEFB fractions. Hydrolyzates from cellulose-rich fraction, slurry (a mixture of cellulose-rich fraction and hemicellulose-rich fraction), and hemicellulose-rich fraction were used as the cultivation media for fungal growth. The corresponding yield of fungal biomass from each medium was 0.62 ± 0.07 g/g glucose; 0.41 ± 0.02; and 0.61 ± 0.13 g/g fermentable sugars, respectively. These results showed thatRhizopus delemarCBS 145940 could be grown in all the hydrolyzates from the OPEFB fractions. Nevertheless, in order to obtain higher fungal biomass, supplementation of nutrition was needed.
Preliminary study to investigate cellulose biodegradability of Bacillus - Aspergillus and Neurospora Crassa on cassava peels (Manihot Esculenta)
Authors: Tran T , Loc H H , Ha N T V , Tan L V , Le D A , Hong L T A
Published: December 2020

Cassava peel holds an abundance of nutrients that could be utilized as fertilizer in agriculture. However, high cellulose contents make it hard for organic digestion, thus slow down the absorption for plants. In this study, we investigate microorganisms for effective cellulose degradation of cassava peel waste collected directly from Hung Duy Tapioca Starch Factory in Tay Ninh Province, Viet Nam. Experiments evaluate the decrease of mass cassava peel of the two groups of Bacillus - Aspergillus and positive control strains such as Neurospora Crassa. The sample was tested on Czapek - Dox liquid culture medium, a method of assessing the dry mass difference of samples used to assess biodegradability in 28 days. Besides, tests to assess the production of products and environmental parameters such as glucose and pH were recorded. Initial results showed that the combination of Bacillus and Aspergillus provides the highest glucose concentration, reached 16.52 mg/ml and digests 53% of the cassava mass compared with a combination of Neurospora Crassa reached 11.45 mg/ml and 46% of the cassava mass. Comparison results also showed that the action potential of microorganisms was stronger when combined and provided evidence that the formation of combinations of microorganisms would work well in probiotics, which brings better environmental treatment efficiency.
Piper betle: a review on its bioactive compounds, pharmacological properties, and extraction process
Authors: Azahar N I , Mokhtar N M , Arifin M A
Published: December 2020

Piper betle is a well-known medicinal plant that cultivated primarily in Southeast Asia. This plant is made up of a large number of bioactive compounds such as tannins, flavonoids (quercetin), eugenol, hydroxychavicol and chavibetol that represent the major components of the plant. This plant has been extensively studied for its pharmacological properties such as antimicrobial, anticancer, antioxidant, antidiabetic and anticancer. Many techniques have been used in Piper betle extraction such as soxhlet extraction, sonication extraction, maceration, ultrasound assisted extraction (UAE), supercritical fluid extraction (SFE) and microwave assisted extraction (MAE). Various benefits of Piper betle extract have been well utilized by the production of numerous types of plant-based products and to date, research on new products based on Piper betle is still being done. Application of Piper betle extract resulting in wide possibilities of usage in future product development. The quality and safety of Piper betle studies provide by toxicity test shows the Piper betle extract exhibit little to none toxicity level at respective concentration. This article aims to present a review of previous studies and research works conducted on Piper betle to serve as a source of additional information for future research related to the Piper betle.
Kinetic study on polyphenol and antioxidant activity from karonda fruit (Carissa carandas) extraction via microwave
Authors: Thanh-Thuy D , Quoc-Duy N , Van-Linh N T
Published: December 2020

Karonda fruit (Carissa carandas L.) is a tropical fruit rich in biological value due to its high total polyphenol content with potential antioxidant activity. In this study, the kinetics of total polyphenol and antioxidant activity extraction from the karonda fruit by microwave-assisted extraction technique was performed. Microwave power varies from 150, 300, and 450 (W); the ratio of material/solvent varies from 1:20, 1:40, and 1:60 (g/mL). The results show that changes in total polyphenol concentration and antioxidant activity during extraction can be predicted by a second-order kinetic model. Increasing the microwave power or amount of extraction solvent had the effect of increasing the extraction efficiency and extraction rate constant. However, the saturation concentration and the initial extraction rate increased when MW power increased or the amount of extraction decreased. In further study, the highest quality of extract, collected at the optimized conditions of microwave-assisted extraction, could be used to develop new food products for the health benefits of customers.
Formulation for a Soursop (Annona muricata L.) Nectar Supplement using Response Surface Methodology for Optimization of Food Thickener
Authors: Thi Tran Nhi Yen , Phat Dao Tan , Pham Van Thinh , Quyen Nguyen Nhan , Thanh Tam Huynh Ngoc , Truc Tran Thanh
Published: December 2020

Soursop, due to its nutritional properties, is gaining attention in the food and beverage industry. Soursop nectar, as a beverage, provides vitamins, antioxidants, and energy. Studies on how additives could alter sensory properties of the product might satisfy the needs of consumers for products with better visual qualities. The mixing of Pectin (PT), carboxymethyl cellulose (CMC), and xanthan gum (XG) directly affects the viscosity in the nectar. Optimization by response surface methodology showed that PT-CMC and XG-CMC interactions were significant at <0.05. The coefficient of determination of the model was high (R2 = 0.9847). The lowest viscosity of the soursop nectar was 70 mPa.s, achieved by following contents of additives: 0.01378% of PT, 0.0071963% of CMC and 0.0051443% of XG.
Effect of Type of Nitrogen Sources and Concentration on Protease Production: Fish Waste Hydrolysate as a Potential Low Cost Source
Authors: Zainuddin F H , Chua G K , Chew F N , Samah R A , Mortan S H , Yazid N A
Published: December 2020

Fish waste hydrolysate is obtained from hydrolysis process of a fishery industry waste. It can be a good substrate source for the production of protease via a fermentation process. Protease covers above than 50% of the global industrial enzymes market and is regarded as an enzyme which is widely used in many applications. This research aims to determine the effect of the type of nitrogen sources and nitrogen source concentration on protease production from the fish waste hydrolysate. The experiments were done using one factor at a time (OFAT) of type of nitrogen sources and nitrogen source concentration in submerged fermentation (SmF) of 10% (v/v) Bacillus cereus (ATCC 10876). In the first stage, the variation of type of 1% (w/v) nitrogen sources such as fish waste hydrolysate, beef extracts, yeast extracts, tryptone, peptone and skim milk powder that mixed with the basal media were compared to evaluate the highest protease production. Then, the concentration of fish waste hydrolysate was varied from 1% to 3% (w/v) to analyse the production trend of protease. The protease activity and total protein content were then analysed by protease assay using tyrosine as a standard and Bradford method, respectively. Upon the observation, 1% (w/v) nitrogen sources on protease production revealed that the fish waste hydrolysates and beef extracts were capable to produce a high amount of protease (23.659 ± 0.38 U/mL and 28.7631 ± 0.59 U/mL, respectively). Among the concentration tested, 3% (w/v) of fish waste hydrolysate was found to be the highest protease production (190.85 ± 0.38 U/mL). Therefore, the fish waste hydrolysate has a potential as a low-cost source for protease production.
Antibacterial evaluation of Malaysian Kelulut, Tualang and Acacia honey against wound infecting bacteria
Authors: Aspar M M , Edros R , Hamzah N A
Published: December 2020

Bacterial infection is the most common contamination on wound. Honey is one alternative plant by-product that can be used as treatment to the bacterial infection. This study aims to evaluate the antibacterial properties of Malaysian honey represented by Kelulut, Tualang and Acacia against fourteen clinically isolated bacteria strains from wound. Agar well diffusion assay was utilised to measure the diameter of inhibition zone. Determination of minimum inhibitory concentration and minimum bactericidal concentration were performed to evaluate the bacteriostatic and bactericidal effects of the honey. The antibacterial properties of Malaysian honey were compared with manuka honey (UMF 18+). Kelulut, Tualang and Acacia have the diameter of inhibition zones that ranged from 10.7 to 24.5 mm, 9.2 to 17.7 mm and no inhibition to 15.3 mm, respectively. Kelulut, Tualang and Acacia showed bacteriostatic effect against the bacteria at concentration of 50% (w/v) and below. Kelulut was the only honey that owned bactericidal effect against the fourteen bacteria while the effect was absence in Tualang and Acacia on E. coli, K. pneumonia, E. clocae and P. mirabilis. The antibacterial properties of Kelulut was comparable to manuka honey since both honey demonstrated bacteriostatic and bactericidal effects against the fourteen clinically isolated bacteria.
Process optimization of catalytic steam reforming of toluene to hydrogen using response surface methodology (RSM) and artificial neural network-genetic algorithm (ANN-GA)
Authors: Mohidin Yahya H S , Saidina Amin N A
Published: December 2020

Catalytic steam reforming of toluene (SRT) over nickel-cobalt supported on modified activated carbon for hydrogen production has been investigated. The center composite design of experiment in response surface methodology (RSM) was initially applied to optimize the catalytic SRT for hydrogen production before being utilized in the model building of the hybrid artificial neural network-genetic algorithm (ANN-GA). The genetic algorithm was carried out over the ANN model to achieve the maximum target response. The process optimization modeling using the best fitness function gave an insight of the optimal operating condition in SRT over the prepared catalyst. The results conferred that maximum hydrogen yield could be obtained at the optimal conditions of 700 °C temperature, 0.034 ml/min feed flow rate, 0.1 g catalyst loading and S/C ratio of 1 by ANN-GA model, and 762 °C temperature, 0.022 ml/min feed flow rate, 0.3 g catalyst loading and S/C ratio of 5.6 by the RSM model. Predicted results from ANN model were in higher agreement with the experimental data at R2=0.95 compared with the RSM model.
Adsorption of chromium (III) ion on biosorbents prepared from Leucaena leucocephala tree
Authors: Sheltami R M , Haweil W M , EL-Omame N F , Bader N , Almabrouk S , Alshelmani N , Elsupikhe R F , Hammad I
Published: December 2020

Biosorbents (fiber, treated fiber, and charcoal) from the Leucaena leucocephala tree were prepared in this study. The potential of the biosorbents as metal capture (removal percentage %R) for chromium (III) (Cr+3) from aqueous solution was examined. The concentrations of the Cr+3 solutions were measured before and after the adsorption to investigate the %R using atomic absorption spectrometry (AAS). Moreover, the specific surface area (A) of the biosorbent samples was evaluated after measuring the adsorbed acetic acid onto the samples. From the results, A and %R were found in the order of charcoal > treated fiber > fiber. The highest values of A and %R were about 423 m2g−1 and 97%, respectively. This finding suggested the high potential of Leucaena charcoal usage as chromium ions capture compared to fibers and treated fibers.
Kinetic and Isotherm Modelling of the Adsorption of Congo Red Dye onto NiFe2O4 and NiFe2O4 decorated Exfoliated Graphite
Authors: Tan L V , Thinh P V , Tham N T H , Sy D T
Published: December 2020

Adsorption using novel materials is a common and highly applicable process in remediation of hazardous dyes in wastewater. Herein, we attempted the synthesis of NiFe2O4 decorated-exfoliated graphite (EG@NiFe2O4), an inexpensive and environmental benign material, and analyzed the adsorption process of the as-synthesized adsorbent against Congo red dye. Kinetic of the adsorption was investigated using various models including first-pseudo kinetic, second-pseudo kinetic, Bangham model and Elovich model. Isotherm of the process was evaluated by Langmuir, Freundlich, Temkin and Dubinin − Radushkevich model. Lastly, thermodynamic parameters of the adsorption towards Congo red dye was calculated. Our findings indicated that kinetic and isotherm of the adsorption process of both adsorbents (EG@NiFe2O4 and NiFe2O4) could be well explained by the pseudo-second-order model (R2 > 0.99) and Langmuir isotherm (R2 =) respectively. In addition, kinetic parameters showed that EG@NiFe2O4 possesses greater adsorption capacity in comparison with NiFe2O4. Estimated thermodynamic parameters also indicated the spontaneous and endothermic adsorption (ΔG=) of the EG@NiFe2O4 composite against Congo red dye.
Water quality monitoring along Kinta River in peninsular Malaysia
Authors: Mustafa M R U , Isa M H , Borhanuddin F F , Mannan H A , Haneef T
Published: December 2020

Rising trend of solid waste production particularly in town and city areas has caused numerous environmental pollutions. Population growth, economic and lifestyle patterns are the factors that lead to the alarming rate of solid waste production. Landfilling is widely used for disposal of wastes due to its low operation and maintenance costs. However, leachate discharged from landfill could be a problem to surface and groundwater if it is not adequately treated. So, the investigation of the transportation and transformation phenomena of micro pollutants along the river receiving discharge from landfill leachate is mandatory. This study is carried out to investigate the water quality as well as to detect the presence of endocrine disrupting compounds (EDCs) along Kinta river in Peninsular Malaysia. Water quality parameters i.e. biological oxygen demand, chemical oxygen demand, ammoniacal nitrogen, total suspended solids, dissolved oxygen and pH were recorded to calculate the water quality index (WQI). The identification of EDCs was carried out using gas chromatography–mass spectrometry analysis. Water quality index result showed that the status of the river in both months fall under good and medium status where it requires intensive/conventional treatment for consumable and drinking purposes. None of the EDCs was detected in any of the samples analysed in the present study. It is believed that the information gained are useful and beneficial for decision making authority.
Recovery of saccharides from lignocellulosic hydrolysates using membranes: A mini review on significant parameters
Authors: Ghazali N F , Razak N D A
Published: December 2020

The use of lignocellulosic biomass has received a lot of attention due to concerns for environmental sustainability and an increasing global waste problem. In order to solve these problems, lignocellulosic biomass can be converted to fuels and chemicals. Since lignocellulose biomass is a renewable feedstock, the conversion process solves the waste problem and produce chemicals simultaneously. However, one of the major challenge in the development of biorefineries is the separation and purification of the biomass hydrolysates. Effective recovery of saccharides and the removal of impurities such as acetic acid and furfural are required as these compounds can inhibit the fermentation process. In this paper, a critical review of membrane technology related to the recovery of saccharides from lignocellulosic hydrolysates is presented. Effects of membrane materials, operating conditions and feed characteristics on the selectivity and productivity of the membrane processes are discussed. The challenges and future outlook of membrane assisted saccharide recovery are also presented.
Synthesis and Characterization of Magnetic Expanded Graphite Material (EG@CoFe2O4) Through Sol-Gel Processing
Authors: Tham N T H , Thinh P V , Uyen D T T , Tien N A , Thanh N T , Sy D T
Published: December 2020

The development of novel materials is indispensable to industrial development due to their instrumental role in medical and decontamination applications. Expanded graphite (EG) possesses a number of advantages including pore structure, non-toxicity and ease of recoverability, making it suitable materials for a wide array of possibilities in many fields. In this paper, a material composite based on expanded graphite (EG) and cobalt ferrite (CoFe2O4) was successfully prepared by the direct sol-gel process. The obtained EG@CoFe2O4 was then characterized using a number of analysis techniques including scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) and Fourier transform infrared spectroscopy (FT-IR). The results indicated successful impregnation of CoFe2O4 into the EG matrix. The as-synthesized EG@CoFe2O4 is also uniform and possessed good crystallinity. The isotherm of the obtained EG@CoFe2O4 material seems to follow the typical type IV isotherm and the pore size of the materials ranged from 2-55 nm.
Essential oil from Amomum Longiligulare T.L. Wu cultivated in Ninh Thuan province, Vietnam
Authors: Anh T T , Bao Ngoc N H , Phuc N D , Nhat D D , Danh P H , Bach L G
Published: December 2020

Amomum Longiligulare T.L. Wu fruit (A. Longiligulare) is a traditional Chinese medicine used to treat indigestion, cough and abdominal pain. In addition, it can create a nice refreshing effect in the mouth and tends to reduce body weight. In this research, A. Longiligulare fruit essential oil was successfully extracted by the hydrodistillation method. A. Longiligulare from Ninh Thuan province in Vietnam gave high extraction yield, which was about 4.6 ml/100g on weight dried basis. The optimum condition for hydrodistitllation without immersing A. Longiligulare powder at particle size smaller than 1 mm, at 1/8 material-water ratio, at water flow rate 2.7 g/min after 3 h distillation. Significantly, the high concentration of D-Camphor (46.714 %) and Bornyl acetate (31.809 %) were detected in essential oil from Ninh Thuan’s A. Longiligulare.
Effect of Nano-fibril Cellulose (NFC) Filler towards the Swelling and Diffusion Behavior of Superabsorbent Polymer Composite
Authors: Lim B R , Mazlan S N A , Ghazali S , Abd Rahim S , Jamari S S
Published: December 2020

Superabsorbent polymers (SAP) exist as a three-dimensional network consisting of branched or linear chains that are chemically or physically crosslinked and possess the ability to retain large amounts of fluids. To be in coherence with the global demand for more biodegradable materials, nano-fibril cellulose (NFC) is introduced as fillers during the synthesis of SAP. The objective of this study is to investigate the effects of different amounts of NFC addition to swelling and diffusion behavior of the final product (SAP/NFC). Inverse suspension polymerization was employed to produce the NFC/SAP, in which acrylic acid (AA) was used as a monomer, acrylamide (AM) as co-monomer and N, N’-Methylenebis(acrylamide) (NNMBA) as the crosslinker. The reaction was conducted at temperature, 55°C for 3 hours. In water absorbency analysis, SAP with 0.006 wt% of NFC shows the highest water absorbency, up to 135%. Swelling kinetic study shows that all SAP exhibit second order of swelling kinetic, and obeys Fickian diffusion behavior. FTIR analysis confirmed the characteristic of SAP and the presence of NFC by identifying C=O, N-H, O=C-H, C-N, O-H, C-H, C=C, C-H, and C-OH bonds. The morphological study shows that the presence of NFC inhibits the formation of SAP in regular bead shape. In thermal stability analysis, SAP with 0.006 wt% of NFC shows the highest thermal stability compared to the other SAPs. It is concluded that the addition of 0.006 wt% NFC is the most optimum condition for cellulose-based SAP synthesis due to the highest water absorbency and thermal stability.
The Effects of Concentration Ratios on the Particle Size of CHI-ALG-CaCl2 Nanocarriers
Authors: Jalani R I , Edros R Z
Published: December 2020

Nanotechnology is highly desirable in numbers of industry including cosmeceutical and pharmaceutical. However, the nanoparticle size is greatly varied by the method of synthesising them such as the addition of calcium chloride. Hence, the present study was carried out to investigate the effect of calcium chloride concentration on nanoparticle size when added to the chitosan and alginate nanocarriers. For this purpose, we have performed the preliminary study on the antioxidant activities of Cymbopogon sp. extracts obtained through decoction and infusion method. From this preliminary study, the optimal mixture ratio of extract, including five different ratios of CHI-ALG/CaCl2 nanocarriers which were prepared with ratio of 1:3:0, 1:3:2, 1:3:5, 1:3:10 and 1:3:20 was used to formulate the nanocarrier. Comparing both methods, decoction gives the highest antiradical activity which indicating strong antioxidant potential compared to infusion, are selected to be formulated into nanoparticle. CHI-ALG/CaCl2 nanocarriers were then synthesised to encapsulate antioxidant extracts for topical delivery. Each sample of nanoparticles was evaluated for its size distributions, polydispersity index (PdI) and zeta potential by dynamic light scattering using DelsaMax Pro (Beckman Coulter, USA). The experiment was conducted with five different ratios of CHI-ALG/CaCl2 nanocarriers which were prepared with ratio of 1:3:0, 1:3:2, 1:3:5, 1:3:10 and 1:3:20 in a volume of 50 ml with 1:3:0 acts as a negative control. The best particle size was observed at 1:3:2 mixture ratio with 0.76-fold change (350.47 ± 36.12 nm) from the control (460.03 ± 107.17 nm) which falls in the acceptable range of desirable size of nanoparticles. The nanoparticles produced in this study showed PdI values less than 1, showing good uniformity. The zeta potential value for the all mixture ratios are high (>20 mV) which is able to prevent aggregation of the nanoparticle. As a conclusion, addition of calcium chloride at 1:3:2 to chitosan and alginate has improved the size of nanoparticles containing antioxidant extract of Cymbopogon sp.
Microwave-assisted hydrodistillation and determines volatile components of essential oils from Calamondin (Citrus
microcarpa) shells
Authors: Ngo T C Q , Ngo H D , Tran T K N , Le X T , Huynh C M
Published: December 2020

Since the industrial economic development, natural compounds have received much attention and study in recent years. Essential oils (EOs) that contain many volatile constituents and aromatic compounds have been around for a long time but are still considered today due to their natural characteristics and unique application. In this study, the leaves of Calamondin (Citrus microcarpa) shells were used to investigate the yield of essential oil extracted by the Microwave-assisted hydrodistillation (MAHD). Calamondin essential oil is determined by the microwave assisted hydrodistillation method and analyzed by GC-MS. Extraction essential oil Calamondin with MAHD in optimal conditions for 45 min, 300W capacity and 1:3 shells/water ratio. The main components of volatile compounds in Calamondin essential oils include limonene (96.039%), β-myrcene (0.953%), 1R-α-pinene (0.266%), sabinene (0.55%), 1,6-cyclodecadiene (1.611%), ϒ-eudesmol (0.207%), β-eudesmol (0.232%), α-eudesmol (0.185%). The oil produced by microwaves assisted hydrodistillation (MAHD) method was found to have higher levels of compounds and significant economic values.
The effects of influencing parameters on the Eucalyptus globulus leaves essential oil extraction by hydrodistillation method
Authors: Ngo T C Q , Tran T H , Le X T
Published: December 2020

This study examines the effects of influencing parameters to Eucalyptus globulus essential oil (EOs) in the hydrodistillation process including extraction temperature, time, and raw material to water ratio. The study also investigated the chemical composition of Eucalyptus globulus EOs by Gas chromatography-Mass Spectrometry (GC-MS). Based on the single factor investigation method, the yield of the EOs for 2.2% in the conditions including the leaves size about 0.5 mm, with the ratio of the leaves to water was 1:4 (g/mL), at 75 minutes in the extracting temperature of 120°C. The analytical results showed that the composition of Eucalyptol (35,034%), followed by α-Pinene (17,860%), β-Pinene (11,022%), α-Terpenol (4,756%), caryophyllene oxide (4,554%), camphol (2,123%), and other ingredients with content less than 1%.
Evaluation of chemical composition in essential oils from Schefflera octophylla L. Hai Duong province in Vietnam
Authors: Tran Q T , Pham Q L , Pham M Q , Tran T K N , Pham T H H , Luu V H , Than V T
Published: December 2020

Schefflera octophylla L is a traditional medicine that exhibits a wide range of biological activities. However, the phytochemical content of S. octophylla L.essential oil is limitedly known. In the present study, S. octophylla L. grown in Hai Duong province (Vietnam) was extracted for essential oil by using hydrodistillation method. The resulted S. octophylla essential oil was further analyzed for its composition of volatile components by GC-MS analysis. Results have shown that the extraction process yielded 0.162 wt% of S. octophylla essential oil. In addition, the content of volatile substances in the obtained essential oil accounted for 97.07%, with main constituents known to have significant medicinal value such as myrcene (9.0%), elemene  (6.67%), caryophylene  (= caryophylene ) (24.91%), selinene  (6.30%) and selinene  (7.29%). These findings provide a helpful insight to S. octophylla L phytochemical profiles for further studies on the plant applications in the fields of pharmaceuticals, cosmetics, agriculture and therapeutic uses.
Formulation of a Floor Cleaning Product using Lemongrass (Cymbopogon citratus) Essential Oil and Evaluation of Foamability and Foam Durability
Authors: Tran T H , Pham T N , Ngo T C Q , Le T H N , Mai H C , Do T S , Tran T K N
Published: December 2020

The growing demand for natural products has spurred the idea of replacing synthetic fragrances with essential oils with antibacterial properties. Essential oils distilled from commercially valuable Cymbopogon citratus species has citral as a major component and finds a wide range of application such as flavors and aromas in perfumes, cosmetics, soaps, and detergents and in the pharmaceutical industry. Via hydrodistillation, the extraction yield of essential oil reached 0.29%. The components for formulation of the cleaning product were determined through a survey of active ingredients: 4.5% Sodium Lauryl Ether Sulphate (SLES), Ethylendiamin Tetraacetic Acid (EDTA-2Na), 0.7% Coco Amido Propyl Betaine (CAPB), 1% Hydroxyethylcellulose (HEC), Sodium Benzoate, 0.3% Butylated hydroxyanisole (BHA), 0.1% NaCl and 0.2% lemongrass essential oil. The finished product was evaluated based on the foaming ability and durability of the emulsion. At the same time, samples stored at different conditions (e.g. room temperature, acceleration, thermal shock) were evaluated for its durability. The results show that citronella oil can be used as a valuable cosmetic material, an antibacterial agent, while not adversely affecting the usability of floor cleaning liquid.
Water quality control of Tasik Kejuruteraan UKM water channel using Artificial Neural Network and Neural Fuzzy Network
Authors: Md Nor N , Mohd Fuad M N , Abd Rahman N
Published: December 2020

The water quality of Tasik Kejuruteraan UKM water channel is an issue that should be emphasized because excess water will be discharged to Sungai Langat where this river is the source of water supply for the residents in some part of Klang Valley area. The water quality parameters must comply with the standard assigned by Malaysian’s Department of Environment (DOE). As a first step towards proper monitoring programme, a proper analysis of the water quality should be conducted thoroughly. As such, this study composed of two parts. First, experimental investigation of the water quality of Tasik Kejuruteraan UKM water channel was carried out to assess its environmental quality. Experiment was conducted to determine the Water Quality Index of Tasik Kejuruteraan water channel based upon guidelines as stipulated by DOE. The results indicate that Tasik Kejuruteraan UKM water channel is polluted and proper water quality control should be applied. In the second part of this study, preliminary analysis of artificial neural network (ANN) and neural fuzzy network for water quality control was conducted to determine the suitability of these controllers in water treatment system. Based on the simulations conducted, neural fuzzy network shows better efficacy in the pH control scheme compared with ANN because there is no oscillation detected in the corresponding controlled variable.
Modelling and simulation of hydrogenation of dimethyl oxalate in ethylene glycol production
Authors: Rohman F S , Sulaiman S H S , Aziz N
Published: December 2020

In this work, the production of ethylene glycol was studied through a syngas-derived ethylene glycol route known as the indirect syngas-to-ethylene glycol process via oxalates. The improvement of hydrogenation of dimethyl oxalate process is pivotal in production of ethylene glycol. Therefore, it is noteworthy to analyse the effect of certain operating parameters on the reactor’s performance. Simulation analysis is an effective approach that allows to study the effect of hydrogen to dimethyl oxalate mole ratio (HDMR), Methyl Glycolate to Dimethyl Oxalate Mole Ratio (MDMR) and temperature on the conversion and selectivity of ethylene glycol. The kinetic of hydrogenation reaction in gas phase in the presence of catalyst was developed in Langmuir-Hinshelwood and Hougen-Watson form. A process model within plug flow reactor was developed using the RPLUG in Aspen Plus V10 simulator. The simulation data from literature was used to validate the model. The error obtained in validation for main product (ethylene) and by-product (methanol) found were below 10% which was acceptable. From the simulation, the reactor temperature and HDMR have significant effects on the conversion of dimethyl oxalate and yield of ethylene glycol. On the other hand, MDMR has little influence on the responding variable.
Distance monitoring applications, angle and speed between nozzle and work piece: Ultrasonic detection sensor system of Gas Metal Arc Welding (GMAW)
Authors: Amiruddin M H , Sumarwati S , Shah S N J , Jalil S A
Published: December 2020

The use of human resources in Gas Metal Arc Welding (GMAW) can cause defects, such as lack of penetration and uneven moldings due to the long distance between the blowpipe nozzle to the workpiece. The purpose of this study is to develop the distance monitoring applications, angle, and speed between nozzle and workpiece for GMAW by using an ultrasonic detection sensor system. The distance monitoring tool between the nozzle and workpiece for GMAW was developed based on the ADDIE model. Respondent included two experts of wiring and electronics, three experts of software and quality, and two experts in the mechanical field, selected by using purposive sampling methods. Monitoring tool developed using Arduino Uno programming technology. Besides, high-quality electronic components such as Ultrasonic HCSR04 and MPU6050 Gyroscopes are used. Based on the analysis, the whole application of distance monitoring, angle, and speed between the nozzle and workpiece for the GMAW can work well and suitable for GMAW with excellent ergonomic features that are easy to maintain and used. The study results will provide benefits in the welding industry as it can reduce defects in GMAW, and thus saving the cost of welding errors.
Stem cell spheroid engineering with osteoinductive and ROS scavenging nanofibers for bone regeneration
Authors: Byun Hayeon , Jang Gyu Nam , Lee Jinkyu , Hong Min-Ho , Shin Hyunjung , Shin Heungsoo
Published: December 2020

Stem cell spheroids have been widely investigated to accelerate bone tissue regeneration. However, the directed differentiation of stem cells into osteoblastic lineage and the prevention of cells from damage by reactive oxygen species (ROS) remain challenge. Here, we developed osteoinductive and ROS scavenging extracellular matrix-mimicking synthetic fibers based on epigallocatechin gallate (EGCG) coating. They were then utilized to fabricate engineered spheroids with human adipose-derived stem cells (hADSCs) for bone tissue regeneration. The EGCG-mineral fibers (EMF) effectively conferred osteoinductive and ROS scavenging signals on the hADSCs within spheroids, demonstrating relative upregulation of antioxidant genes (SOD-1 (25.8 ± 2.1) and GPX-1 (3.3 ± 0.1) and greater level of expression of osteogenic markers, runt-related transcription factor (5.8 ± 0.1) and osteopontin (5.9 ± 0.1), compared to hADSCs in the spheroids without EMF. The in vitro overexpression of osteogenic genes from hADSCs was achieved from absence of osteogenic supplements. Furthermore, in vivo transplantation of hADSCs spheroids with the EMF significantly promoted calvarial bone regeneration (48.39 ± 9.24%) compared to that from defect only (17.38 ± 6.63%), suggesting that the stem cell spheroid biofabrication system with our novel mineralization method described here is a promising tool for bone tissue regeneration.
Hot deformation of nickel particles reinforced aluminium based composites: flow behaviour, microstructural evolution and processing map analyses
Authors: Alaneme Kenneth Kanayo , Babalola Saheed Adeoye , Bodunrin Michael Oluwatosin , Chown Lesley Heath , Okotete Eloho Anita , Maledi Nthabiseng Beauty
Published: December 2020

The hot deformation behavior and workability of stir cast Al 6063 alloy reinforced with 6 wt. % Nickel particles was investigated using flow stress-strain plots, microstructural analysis and processing maps. The composites were hot compression tested at temperatures of 200 °C, 250 °C, 300 °C, 350 °C and 400 °C, and strain rates of 0.01, 0.1, 1, and 10 s−1, while scanning electron microscopy was utilized for characterization of the ensuing microstructures. The results show that the flow stress generally decreased with increase in deformation temperature, while anomalous flow stress oscillations, linked to the pattern of particle distribution in the matrix, characterized the flow stress - strain rate relations at 0.01 s−1 strain rate. The Murty’s and Gegel’s criteria utilized to establish domains of instability at the global strain of 0.5 were found to vary considerably and the combination of both left a very narrow safe processing window for the Al6063/Ni
p
composite. Safe regions with peak power dissipation efficiencies occurred at temperature range of ∼390 °C–400 °C and 0.01 s−1 in the lower domain and 260 °C–350 °C and 10 s−1 in the upper domain. The dominant flow softening mechanisms were established to be dynamic recrystallisation and dynamic recovery at the lower domain and upper domains, respectively.