Thai Science and Technology Journal

Comparison of Phytochemicals and Antioxidant Capacities of Ethanol Extracts from Different Parts of Elsholtzia beddomei C.B.Clarke ex Hook. f.

2023-11-02T15:29:09+07:00

The objectives of this research were to investigate and compare the phytochemical screening and antioxidant capacity of crude ethanol extracts from flowers, leaves, stems and roots of Elsholtzia beddomei C.B. Clarke ex Hook. f. In phytochemical screening, phenolics, saponins, flavonoids, steroids, alkaloids, anthraquinones, diterpenes and triterpenes were found as constituents in all extracts. Determination of total phenolic and flavonoid contents was done using the Folin-Ciocalteu reagent and aluminum chloride colorimetric methods, respectively. It was found that the leaf extract had the highest total phenolic and flavonoid contents (22.345 ± 0.491 mg GAE/g dry sample and 52.730 ± 0.344 mg QE/g dry sample, respectively). The antioxidant activities were investigated using DPPH, ABTS, and FRAP methods. The study found that leaf extracts had the highest antioxidant activity using all three testing methods. The DPPH method and ABTS reported the results as an IC₅₀ value (1.428 ± 0.302 and 96.433 ± 11.303 µg/mL, respectively). The reducing power was assessed for the electron-donating ability test using the FRAP method. The results were reported as a FRAP value equal to 5.004 ± 0.108 mg Fe²⁺/g dry sample. The results of this work indicated that the leaves of E. beddomei are good sources of phytochemicals and potential antioxidant activity.

Effect of Electrode Placement on Flow pattern Enhancing Hot-Air Drying Rate with Electrohydrodynamic Force

2023-11-20T14:25:55+07:00

This research aims to elucidate the effect of electrode placement both in the flow direction (E_x) and normal to the flow direction (E_y) on airflow subjected to electrodynamic force (EHD) enhancing hot-air drying rate. Additionally, numerical simulations of two-dimensional fluid flow with EHD force are conducted to explore the effect of electrically-driven flow patterns on enhancing the drying rate (DR). In the experimental setup, four electrode wires are suspended perpendicularly from the upper wall of the wind tunnel, while two ground wires, having the same length as the packed bed, are positioned above the packed bed surface and aligned parallel to the flow. At the inlet of the test section, the average velocity and temperature of inlet air are controlled at 0.33 m/s and 60^OC, respectively. In addition, a high electrical voltage of 20 kV is applied. The initial saturation (S_int) of the packed bed is 0.5, and the drying period lasts for 12 hours.

The experimental results indicate that, even in the absence of applied heat, the EHD force can enhance the evaporation of moisture from the packed bed. Moreover, the DR of the hot-air flow with EHD is approximately 1.4 – 2.2 times higher than that without EHD. Higher DRs are observed when E_x is positioned near the front end of packed bed surface, but tend to decrease when E_x is located further downstream. Simulation results illustrate that the effect of EHD force induces vortices in front of the electrodes and also increases the air velocity behind these vortices. However, the occurrence of vortices results in low airflow velocities in their front regions. Consequently, when E_x is increased, vortices and high air velocity manifest further downstream. Moreover, the EHD force weakens as the gap between electrode and ground increases. Therefore, when E_y > 4 cm, the DR tends to decrease. However, when E_y = 2 cm, the EHD force only influences the low-temperature layer of airstream near the surface, compelling it towards the packed bed surface. As a result, surface temperature is not significantly increased.

Detecting Human Faces in Three Different Environmental Conditions using YOLOv4

2023-11-13T13:16:59+07:00

This research focuses on detecting human faces using the YOLOv4 model and compares it with other algorithms used in face detection studies. The dataset consists of a large number of images taken in three significantly different environmental conditions: indoors with low light, indoors with sufficient light, and outdoors during normal daylight hours. The performance of each algorithm in detecting human faces is measured and compared with four other algorithms: Viola-Jones Face Detection Algorithm, DeepFace, FaceNet, and MTCNN. The results of the experiment show that the YOLOv4 model outperforms the other algorithms in all three environmental conditions. According to confusion matrix evolution, the average precision for detecting human faces using the YOLOv4 model is 0.96, with a recall of 0.93 and an f1-score of 0.94. Therefore, the YOLOv4 algorithm is the most effective algorithm for detecting human faces in this study.

Influence of Organic Fertilizer on Growth and Quality of Kalmegh

2023-12-12T14:55:43+07:00

Kalmegh is a medicinal plant known for its properties in alleviating pneumonia caused by the coronavirus (COVID-19). This study aimed to investigate the application of organic fertilizer on the growth, yield, and yield quality of Kalmegh. The experimental design was a completely randomized design (CRD) with 3 replications and 5 treatments. Specifically, the treatments included treatment 1 as a control (no organic fertilizer) and treatments 2 to 5, in which organic fertilizer was applied at 0.5, 1.0, 1.5 and 2.0 times the dose recommended by the Department of Agricultural Extension. This corresponded to the application of organic fertilizer at 62.5, 125, 187.5 and 250 g/pot. The result showed that the application of organic fertilizer at 250 g/pot provided the highest leaf dry weight, which was not significantly different from the application of organic fertilizer at 125 and 187.5 g/pot. The increased dosage of organic fertilizer reduced the concentration of phosphorus in the plant tissue. However, the different doses of organic fertilizer had no effect on the andrographolide content. Regarding the chlorophyll content in the leaf, the application of organic fertilizer at 187.5 g/pot resulted in the highest chlorophyll a and total chlorophyll, which was not significantly different from the application of organic fertilizer at 125 and 250 g/pot. Consequently, the application of organic fertilizer at 125 g/pot is a suitable dose for the production of Kalmegh.

Using a Mixture of Corn Gluten Meal and Meat and Bone Meal to Replace Dietary Fishmeal and a Mixture of Corn Gluten Meal and DDGS to Replace Soybean Meal for Juvenile White Shrimp

2023-11-23T09:23:05+07:00

Using alternative protein sources in a 38%P and 7%L white shrimp diet was determined. Test diets consisted of diet 1 containing 12% fishmeal and 28% soybean meal (control). Diets 2 and 3 replaced fishmeal protein with corn gluten integrated with meat and bone meal at levels of 50 and 100%, respectively. Diets 4-6 replaced soybean meal protein with corn gluten integrated with DDGS at levels of 50, 100 and 100% supplemented with phytase 1,000 FTU/Kg, respectively. Three groups of shrimp, each weighting 0.55 g, were fed each diet at 4-10% of body weight per day for 8 weeks. Replacing fishmeal showed that the growth, feed conversion ratio, protein efficiency ratio and protein retention of shrimp fed diets 1 and 2 were not significantly different (p>0.05) but were better than shrimp fed diet 3 (p<0.05). Replacing soybean meal showed that the growths of shrimp fed diet 1 and 4 were not significantly different (p>0.05) but better than shrimp fed diet 5 and 6 (p<0.05). The feed conversion ratio, protein efficiency ratio, and protein retention of shrimp fed diet 1, 4, 5 and 6 were not significantly different (p>0.05). In conclusion, corn gluten integrated with meat and bone meal could replace fishmeal up to 50% and corn gluten integrated with DDGS could replace soybean meal by at least 50% for a 38%P and 7%L white shrimp diet contained 12% fishmeal and 28% soybean meal without impacting growth and feed utilization.

Quality and Antibacterial Activity of Paper Soap Containing Essential Oil from Wan Sao Long

2023-11-22T13:27:33+07:00

This study aimed to develop paper soap infused with essential oil extracted from Wan Sao Long (Amomum biflorum Jack) leaf. The essential oil was extracted using distillation, and its chemical composition was analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). Subsequently, the paper soap was developed, and its physical properties, including general appearance, stability, pH value, foam quantity, foam stability, and sweating, were examined. Additionally, its antibacterial activity against Staphylococcus aureus and Escherichia coli was tested using the agar diffusion method. The results revealed that 4-Hydroxy-2 methylacetophenone was the major chemical component in the essential oil. The developed paper soap exhibited stability with a pH value of 9.69±0.16, a significant foaming volume, and foam stability. The paper soap had a specific fragrance of Wan Sao Long and did not exhibit sweating. The soap demonstrated inhibitory effects against S. aureus and E. coli with average inhibition zone diameters of 12.00±0.50 mm and 8.83±0.29 mm, respectively. However, the antibacterial activity of Wan Sao Long paper soap was less effective than that of antibiotics such as tetracycline and ampicillin. Therefore, paper soap containing Wan Sao Long essential oil possesses antibacterial activity and meets the quality standards.

Growth and Flesh Quality of Cobia Fed with Increased Lipid and Reduced Protein Diet and Increased Carbohydrate and Reduced Lipid Diet

2023-11-07T13:11:23+07:00

Growth and flesh quality of cobia fed with increased lipid and reduced protein diets and increased carbohydrate and reduced lipid diets were determined. Test diets 1-4 contained protein/lipid/carbohydrate ratios of 40%/6%/31% (control), 36%/10%/33%, 36%/6%/36% and 36%/4%/38%, respectively. Groups of fish with an initial weight of 35 g were stocked in 3x3x2.5 M cage in Sri Racha Bay, Chonburi province, with stocking densities of 25 fish per cage and fed each diet to satiation once a day for 6 months. The results showed that the growth and feed conversion ratio of fish fed diet 1 were significantly better than those of fish fed diets 3 and 4 (p<0.05), but not significantly different from those of fish fed diet 2 (p>0.05). The protein efficiency ratio and flesh protein retention of fish fed diet 2 were significantly better than those fish fed other diets (p<0.05). There were no significant differences in condition factor, percentages of flesh and other organs, hepatosomatic and viscerosomatic indices among fish fed all test diets (p>0.05). The flesh protein contents of fish fed diets 1, 2 and 4 were not significantly different (p>0.05), but significantly higher than those of fish fed diet 3 (p<0.05). The flesh lipid contents of fish fed diets 1 and 3 were not significantly different (p>0.05), but significantly higher than those of fish fed diets 2 and 4 (p<0.05). From this study, it was observed that the cobia diet for 35-800 g could reduce protein from 40% to 36% calculated as a reducing rate of 10%, and increase lipid from 6 to 10%, calculated as an increase rate of 66.7%.

Development of Paper Soap Product for Hand Sanitizer Containing Hevea brasiliensis Leaves Extract

2023-11-16T09:31:39+07:00

Objectives: To 1) develop paper soap product for hand sanitizer containing Hevea brasiliensis leaves extract 2) investigate skin irritation in volunteers, and 3) study satisfaction with the paper soap product. Methods: H. brasiliensis leaf extract was mixed with chemicals to produce a hand-washing paper soap product. The physical, chemical and stability of the soap were tested. Skin irritation was assessed in 30 healthy volunteers, and satisfaction with the test product was evaluated in 129 volunteers. Results: The liquid soap contains the following ingredients: H. brasiliensis extract (4.0%), propylene glycol (3.0%), palm kernel oil (25.0%), potassium hydroxide (5.0%), salt (4.5%), essential oil (2.0%), and distilled water (56.5%). The liquid soap is dark brown, clear, with no sediment, having a viscosity of 3777.65±465.6 mPa S, bubble volume of 90.00±5.00 mL, pH of 8.89 ± 0.28, total fat content of 5.53 ± 0.74 %(w/w), and insoluble in ethanol 0.28 ± 0.11 %(w/w). No skin irritation was found in the subjects. Paper soap products were distributed in packaging boxes to 129 volunteers, 109 females and 20 males. The volunteers expressed satisfaction with the packaging design overall at a good level (average was 4.30 ± 0.62). Simultaneously, their satisfaction with paper soap products in terms of product characteristics was also at a good level, with an average value of 4.22 ± 0.58. Regarding product quality, the volunteers expressed satisfaction at a good level, with a mean of 3.93 ± 0.69. Suggestions included the desire for paper soap to produce more bubbles, add more scents, and adding more usable colors. Conclusion: Paper soap products for hand washing containing crude H. brasiliensis leaf extract were developed as an alternative for the general public. It also adds value to natural leftover rubber leaves and serves as a prototype for further industrial production.