Applied Mechanics and Materials Vol. 891

Abstract: This paper aimed to determine the characteristics of physical and mechanical properties of rice straw hand sheet and investigated the optimal conditions for making rice straw paper. The chemical composition of rice straw determined with the TAPPI standards. The conditions of making paper hand sheet composed of pulping time: 2 hours, 4 hours, pulping temperature: 100°C, 130°C, pulping solvent: 2 wt% NaOH, 4 wt% NaOH and bleaching: unbleached pulp, bleached pulp with 2% H₂O₂. The paper hand sheet was tested based on TAPPI methods, basic weight TAPPI- T410-om-93, thickness TAPPI- T411-om-89, moisture content TAPPI- T412-om-93, brightness TAPPI T452 om-92, opacity TAPPI standard T 425 om-91, burst strength TAPPI T403 om-97, tensile strength TAPPI T494 om-01, and tear strength TAPPI-T414-om-88. The results showed that the optimal conditions of rice straw hand sheet including pulping time: 2 hours, pulping temperature: 100°C, pulping solvent: 2 wt% NaOH, and bleaching: unbleached pulp gave the highest the physical and mechanical properties form other conditions. This conditions showed as the basic weight 62.27 g/m2, thickness 259.30 µ, opacity 93.34 ISO%, burst strength 64.75 kPa.m2/g, tensile strength 95.33 N.m/g, and tear strength 473.55mN.m2/g. In this condition, the paper hand sheet used at the lowest concentration of pulping solvent and non-bleached, which reduces environmental pollution.

Abstract: Ethylene is a plant growth regulator (PGR) that mainly influences on growth and development of plant and their agricultural productivity. Ethylene producing from plant tissue is a physiological indicator which refers to the maturity, senescence, or stress of plants. Therefore, a monitoring level of ethylene in plant tissue is necessary for research and commercial processes. Current method measuring gaseous ethylene is costly and take a long time. This research established a new method to quantify ethylene gas in water immersed plant by using an oxidation reaction between oxidizing agent (KMnO₄) and alkene functional group of ethylene under acidic solutions. Then, the leftover KMnO₄ in solution was quantitatively evaluated by spectrophotometry method. An absorbance at the wavelength 525 nm were compared to the standard curve. The purple intensity of KMnO₄ inversely relates to the concentration of ethylene. Water immersions of leaf and flower samples which have different in dissolved ethylene were analyzed under this method. The result showed the difference in ethylene emission between plant varieties (normal tobacco and less-ethylene emission tobacco), plant organs (leaf and flowers) and also organ senescent levels. The result indicates that the concentration of ethylene in water is concordant with the physiology of tobacco leaf and flower. Therefore, the ethylene level in water immersed plant sample can be estimated by this established method.

Abstract: Pleurotus ostreatus, the worldwide edible mushroom, has a potent economic values and medicinal properties. In this study, nutritional properties, antioxidant, and anti-acetylcholinesterase activities of P. ostreatus were investigated. The extracts were prepared by maceration and soxhlet extraction with ethanol and decoction with distilled water. Nutritional analysis showed that P. ostreatus has high content of fibers (45.5%), proteins (20.8%) and carbohydrates (68.4%) with low content of lipids (0.56%). HPLC analysis revealed that P. ostreatus has high content of the potential health promoting of β-glucan (42.8%). Acetylcholinesterase (AChE) is a key enzyme in nervous system. Inhibition of this enzyme is used for the symptomatic treatment of Alzheimer’s disease (AD), the most common disease in aging population. Ellman colorimetric method was used to determine Acetylcholinesterase inhibitory (AChEI) activity. All extracts found containing high AChEI activity (IC50 = 1.75-5.91 mg/ml). Oxidative stress plays a major role in the pathogenesis of AD, thus antioxidant activity was also performed in this study. DPPH assay exhibited all P. ostreatus extracts had high antioxidant activity (IC50 = 0.59-5.47 mg/ml). The results suggested that P. ostreatus should be beneficial for AD treatment and the most efficient nutraceutical and functional foods.

Abstract: Molineria latifolia is a perennial-monocotyle-donous herb and it is well-known in the treatment of melasma, freckle and black spot in Thai traditional medicine. The purpose of this study was to determine the phytochemicals and antioxidant activity in the aerial parts and the underground parts of M. latifolia by water, ethanolic and ethyl acetate extracts. The phytochemicals were analyzed by HPTLC. The antioxidant activity was measured by using the DPPH radical scavenging activity assay, Ferric reducing antioxidant power assay and Total phenolic content was measured by Folin‑Ciocalteu. The result showed the highest antioxidant activity of the underground parts (RW) were extracted by water at EC₅₀=245.03±6.59 µg/mL(DPPH) and 640.03±0.36 Fe²⁺/ mg (FRAP). Consequently, the highest phenolics content was found in the water extract of the aerial parts (LW) (191.70±1.64 µg FA/mg). M. latifolia extracts contain a bioactive compound of Tannin, Flavonoids and Steroid . Tannin and Flavonoid were found in both of parts. In the aerial parts were found steroid extracting by ethyl acetate and ethanolic, as the underground parts were seen steroid extracting by water. It was found that M. latifolia has high bioactive compounds and moderate antioxidant activity. These results for the cosmetic product development in the future.

Abstract: The phytochemicals of the ethanolic extracts of unripe pulp and peel of banana fruits from several banana cultivars belonging to the Musa acuminata species (namely 'Kluai Namwa', 'Kluai Hom Thong', 'Kluai Leb Mu Nang', and 'Kluai Khai') were studied by color reaction test and HPTLC analysis. Kluai Khai pulp showed a highest amounts of ethanolic extractives (ca. 9.70±5.84% of dry material weight). The peel several banana showed similar qualitative phytochemicals. The major of phytochemicals identified in these extracts were alkaloids, flavonoids, tannins and polyphenols. The antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl assay. The analysed Kluai Hom Thong peel ethanolic extract showed a highest antioxidant activity at IC₅₀ = 3.25±0.52 μg/ml and Kluai Hom Thong peel ethanolic extract showed a highest tyrosinase inhibitory effect at IC₅₀ = 2.25±0.91 μg/ml. Kluai Hom Thong peel could be provide a potential natural source of bioactive compounds and could be beneficial to the cosmetic properties.

Abstract: The phytochemicals of the ethanolic extracts of petals and stamens of lotus flowers from several lotus cultivars belonging to the Nelumbo nucifera Gaertn. (namely 'lotus white flower' and 'lotus pink flower') were studied by color reaction test and HPTLC analysis. The lotus pink flower stamens showed a highest amount of ethanolic extractives (ca. 18.33±2.14% of dry material weight). The several the ethanolic extracts of N. nucifera petals and stamens showed similar qualitative phytochemicals. The crude extracts revealed the presence of flavonoids, terpenoinds, tannins and polyphenols. The antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl assay. The analyzed lotus pink flower stamens ethanolic extract showed a highest antioxidant activity at IC₅₀ = 0.61±0.16 μg/ml and lotus pink flower petals ethanolic extract showed a highest tyrosinase inhibitory effect at IC₅₀ = 2.25±0.21 μg/ml. N. nucifera flowers could be provide a potential natural source of phytochemicals and could be beneficial to the cosmetic properties.

Abstract: Benchalokawichian (BLW) remedy is a Thai traditional medicine that has been notified in the List of Medicine Products of the National List of Essential Drugs A.D. 2006 and has long been used as an antipyretic. The phytochemicals of the 70% and 95% ethanolic extracts of were studied by color reaction test and HPTLC analysis. The BLW remedy showed a highest amounts of 70% ethanolic extractives (ca. 3.99 ± 0.60% of dry material weight). The several ethanolic extracts showed similar qualitative phytochemicals. The major of phytochemicals identified in these extracts were alkaloids, flavonoids, tannins, and polyphenols. The antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl assay. The analysed 70% ethanolic extract showed a highest antioxidant activity at IC₅₀ = 526.09 µg/ml and both extracts not showed tyrosinase inhibitory effect. The 95% ethanolic extract showed the greatest anti-propionibacterium acnes activity with inhibition zone of 10.10 ± 0.45 mm and minimum inhibitory concentration (MIC) was 5.05 mg/ml

Abstract: Coconut protein residue from production of coconut oil with extracted Curcuma longa has high antioxidant as curcuminoids, and high protein which are needed for growth performance and survival rate of Juvenile red claw crayfish (Cherax quadricarinatus). The objective of this work was to study the effects of coconut protein residue from production of coconut oil with extracted Curcuma longa in feed to growth performance and survival rate of Juvenile red claw crayfish. The experiment was carried out using plastic bucket systems with three treatment conditions: T1 used pellet (control); T2 used cream protein from virgin coconut oil (VCO); T3 used cream protein from coconut oil with extracted Curcuma longa (COC), respectively. Feed with cream protein from COC and VCO has significant effect on weight gain and feed conversion ratio (FCR) of Juvenile red claw crayfish when compared to Juvenile red claw crayfish in the control diet. FCR in the control group was significantly (p<0.05) higher than those of the treated groups. Weight gain was highest in the T3. Survival rate of every treatment was 100%. The result indicated that the cream protein from COC with high protein and high antioxidant is a potential additive in the Juvenile red claw crayfish diet.

Abstract: This study was conducted to analyze the correlation between traits of fruit mulberry from 71 hybrid accessions. The results revealed that the fruit yield (FY) had intermediately positive correlated to branch per trunk (BPT, r = 0.46). Fruit width (FWI) had very highly positive correlated to fruit length (FL, r = 0.77) and fruit weight (FWE, r = 0.86). Fruit length (FL) had highly positive correlated to fruit weight (FWE, r = 0.91) but had slightly negative correlated to bud per branch (BPB, r = -0.28). Fruit weight (FWE) had slightly positive correlated to branch length per trunk (BLPT, r = 0.27) but had slightly negative correlated to bud per branch (BPB, r = -0.29). Finally, branch length per trunk (BLPT) had intermediately negative correlated to bud per branch (BPB, r = -0.39). Additionally, the economic traits which had highly positive direct effect through fruit yield was branch length per trunk (BLPT, path coefficient = 0.428). The correlation and path analysis are suggested for the direct selection of branch length per trunk for fruit mulberry yield improvement. This result showed the relationship among traits and making indirect criteria for selection fruit mulberry in breeding system.