ISSN: 0125-2364, Online ISSN: 2586-9531

Volume 44 No.1 January-March 2016


P.1-21

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Enzymatic Silk Degumming: The Challenged Process for Upgrading Quality of Thai Silk

การฟอกกาวไหมด้วยเอนไซม์: ความท้าทายของกระบวนการ เพื่อยกระดับคุณภาพไหมไทย

เปรมวดี วงษ์แสงจันทร์

Signature of Thai silk is found in its texture, special luster, and being a handcraft with distinctive color patterns and weaving designs. A possible way to efficiently improve the overall production of Thai silk is to replace the usage of chemicals with a sericin-specific protease in a silk-degumming process. The enzyme can specifically hydrolyze sericin without damaging fibroin with an absolutely defined endpoint under a lower temperature than that used in traditional methods; thus providing a better control of the process as well as higher quality and uniformity of degummed silk. The use of enzymatic degumming could diminish the problems in subsequent dyeing and weaving steps due to unequal quality of sericin in raw silk supplied by different producers. In addition, it promotes public understanding and core values of green technology - the chemical usage as well as energy and water consumption are reduced, therefore lowering the amount of wastes; the enzyme is possibly reused in another batch of degumming process; and water can be recycled for other purposes. Moreover, sericin may be recovered to make new products and generate additional incomes, which should surpass the cost of the enzyme. However, it is sustainable only if a good administrative system and management of sericin application are implemented, which include enzyme production, technology transfer, logistic on collecting of sericin, new production lines, and marketing strategies for Thai silk and the new products.


P.22-31

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Utilization of Sericin on Water Mold Growth Inhibition and Serum Substitution in cell culture

การใช้เซริซินในการยับยั้งการเจริญเติบโตของราน้ำ และการใช้ทดแทนซีรัมในการเพาะเลี้ยงเซลล์

Monthira Monthatong* and Wuttiwat Jitjak

Sericin is a natural adhesive protein to attach fibroin fiber in silk cocoons which is removed during raw silk production. In this study, Sericin protein was extracted from cocoons of two varieties of silkworm (Bombyx mori L.); Nang Noi Srisaket and UB1, by three methods including 1) boiling in 1.2% citric acid, 2) boiling in distilled water and 3) heating in 8 M urea containing 2% β-mercaptoethanol at 80 oC. Sericin powder was then prepared from boiling in 1.2% citric acid method. The protein patterns from these methods were assayed by SDS-PAGE. The potential of sericin in inhibiting the growth of water mold (Saprolegnia diclina) was investigated by soaking water mold hyphae in various sericin concentrations and timings before transfer to GY agar. Furthermore, the ability of sericin in serum replacement in A549 human lung alveolar cell culture was investigated. The results on SDS-PAGE showed the molecular weight of sericin ranged from 5 to 116 kDa. The pretreatment S. diclina hyphae in sericin solution was able to decrease the density and/or the length of water mold mycelium. Those hyphae immersed in 3% of UB1 sericin solution for 120 minutes was significantly inhibited hyphae growth rate (p<0.05) comparing to the control group soaked in distilled water. Moreover, the results of A549 human lung alveolar cell culture indicated that after 72 hrs, cells grown on 0.5% sericin from Nang Noi Srisaket and UB1 provided the highest numbers of viable cells which were 2.75 x 104and 2.5 x 104 cells/ml, respectively similar to those cultured on 10% FBS with x 104 cells/ml. Therefore, sericin is an alternative potential antifungal substance and serum replacement agent.


P.32-42

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Prevalence of Helminths in Gastrointestinal Tract of Family Murinae from Nakhon Ratchasima, Buri Rum and Surin Provinces

ความชุกของหนอนพยาธิในทางเดินอาหารของหนูวงศ์ Murinae จากจังหวัดนครราชสีมา บุรีรัมย์ และสุรินทร์

ญาณิศา นราพงษ์ และ นพคุณ ภักดีณรงค์*

The purpose of this study was to present the prevalence of helminths in gastrointestinal tract of murids from Nakhon Ratchasima, Buri Rum and Surin Provinces. A total of 125 murids during April to October 2014 were collected. 8 species of murids infected with 8 species of helminths (2 cestodes and 6 nematodes). The highest prevalence rate of helminths in murids was 100% in Berylmys berdmorei, 85.7% in Bandicuta savilei, 83.3% in Rattus losea, 68.8% in Bandicuta indica, 54.5% in Rattus exulans, 52.3% in Rattus tanezumi, 42.9% in Mus cervicolor and 28.6% in Mus caroli. The highest prevalence rate of helminths was Hymenolepis diminuta (16.8%), Protospirura siamensis (15.2%), Syphacia muris (14.4), Trichostrongylidae (13.6%), Ptrygodematites sp. (12.8%), Raillietina sp., Syphacia obvelata and Physaloptera sp. (0.8%), respectively. The highest prevalence of helminths  was found in Buri Rum (59.0%) followed by Nakhon Ratchasima (58.1%) and Surin (52.4%). Whereas, the highest total helminth species richness was found in Buri Rum provicnce (7 species) followed by in Naknon Rachasima and Surin provinces (4 species each). The results indicated that murids were important vectors of helminth diseases. This data will be benefit to public health for planning control and prevention from helminths in murids to humans and pets.


P.43-55

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Fungal contamination in peanuts and control by spice essential oils

การปนเปื้อนของเชื้อราในถั่วลิสงและการควบคุม โดยใช้น้ำมันหอมระเหยจากเครื่องเทศ

สุรีย์ นานาสมบัติ*   นพพร กิตติศุภมงคล*   นุชนาฏ หมั่นพลศรี และ ปณิธาน กัณหา

In this study, peanut and peanut products (10 samples each) were analysed for fungal contamination. Percentage of fungal contamination in raw whole peanut and fried peanut samples was analysed by direct plating method, while total yeast and mold counts in ground roasted peanut and sweet peanut samples were analysed by dilution plating method. Raw whole peanut samples (86.2%) were highly contaminated with mold, but fried peanut samples (76.2%) had lower proportion of mold contamination. However, ground roasted and sweet peanut samples had low number of total yeast and mold counts (less than 10 – 7.0x103 CFU/g).  The minimum inhibitory concentrations (MICs) of clove, dill and cardamom oils against Aspergillus flavus TISTR 3041, A. ochraceus TISTR 3557, A. parasiticus TISTR 3276, A. terreus TISTR 3109, A. versicolor TISTR 3460, Alternaria alternata TISTR 3282, Penicillium citrinum TISTR 3437 and A. flavus PN-09 isolated from a raw whole peanut sample were determined. Most fungal species were sensitive to clove oil with the MIC of 1 mg/ml, except for A. versicolor. Dill oil, a less effective oil inhibited growth of most mold strains tested (4 mg/ml MIC), except for  A. ochraceus and A. versicolor, more resistant strains. Cardamom oil was found to be a less effective oil for inhibition of all mold strains tested (16 mg/ml MIC). Therefore, clove and dill oils were selected for use in peanut packaging. Clove and dill oils (4 mg/ml) were applied by coating  the inner surface lids of the petridishes containing peanut seeds. The peanut seeds (100%) were contaminated  with A. flavus TISTR 3041 and A. flavus PN-09 spores. After 7-day storage at 30 ºC, 75% relative humidity, the amount of fungal growth and aflatoxin content in the peanut seeds were determined. Clove and dill oils (4 mg/ml) caused decreasing of fungal growth and amount of aflatoxin produced by both strains of A. flavus in the peanut seeds.


P.56-68

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Comparative Morphology and DNA Evidences Between Dioscorea hispida Dennst. var. hispida and D. hispida Dennst. var. neoscaphoides Prain & Burkill

หลักฐานทางสัณฐานวิทยาและดีเอ็นเอเปรียบเทียบ ระหว่างกลอยและกลอยเขา

เชิดศักดิ์ ทัพใหญ่* และมลิวรรณ นาคขุนทด

Comparative morphology of Dioscorea hispida var. hispida and D. hispida var. neoscaphoides was studied by field and herbarium specimens investigation. The result showed that mostly vegetative and reproductive parts such as tuber, stem, leaf, bulbil, flower, fruit and seed, between two varieties were significant distinction. Moreover, shape of tepal, as well as hair and spine density were also different. On the other hand, the result of DNA study was indicated that D. hispida var. hispida and D. hispida var. neoscaphoides were not distinguished from each other based on only rbcL sequences. Therefore, only the information of morphological study were highly supported their variety status but couldn’t state var. neoscaphoides up to the specific rank.


P.69-78

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Climate Variability on Phenology of Asiatic Mangrove Forest (Rhizophora mucronata Lam.) in Yaring Mangrove

ความแปรปรวนของสภาพอากาศต่อฟีโนโลยีของโกงกางใบเล็ก (Rhizophora mucronata Lam.) ในป่าชายเลนยะหริ่ง

อิสมะแอ เจ๊ะหลง*   อลภา ทองไชย และ อาเด่น ปาลนกวิน

The effect of climate variability on phenology of leaf flushing, flowering and fruiting of asiatic mangrove was conducted in Yaring mangrove forest in Yaring district, Pattani province during 2011-2012. In 2011, the average of rainfall, evaporation, air temperature and soil moisture were 2259.30 ml./year, 614.29 ml./year,  33.57 ˚C/month and 33.45%/month, respectively. The results showed that the trees of asiatic mangrove flushed, flowered and fruited in May–July, September–October and November-December. In 2012, the average of rainfall (2407.50 ml./year), evaporation (598.36 ml./year), average air temperature (33.96 ˚C/month) and soil moisture (30.26%/month).  The flushing and flowering of asiatic mangrove occurred in August–September and November–December. Thus, climate variability might be the main factor on leaf flushing, flowering and fruiting of asiatic mangrove.


P.79-87

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Antibacterial activity from leaf extracts of Mentha cordifolia Opiz. by ethanol extraction

ฤทธิ์ต้านเชื้อแบคทีเรียของสารสกัดจากใบสะระแหน่ โดยตัวทำละลายเอทานอล

รองเดช ตั้งตระการพงษ์* และ จุลจิตร์ ตั้งตระการพงษ์

This study intended to investigate the antibacterial activity of Mentha cordifolia Opiz. extract, which was extracted by ethanol, inhibiting Staphylococcus aureus, Streptococcus pyogenes, Streptococcus agalactiae, Salmonella Typhi, Escherichia coli and Klebsiella pneumoniae by the agar disc diffusion method. It was found that Mentha cordifolia Opiz. extract highly inhibited Salmonella Typhi more effectively than Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Streptococcus agalactiae and Streptococcus pyogenes with a mean clear zone of 13.17±0.05, 12.50±0.05, 12.00±0.07, 11.67±0.06, 11.00±0.03 and 10.50±0.02 mm., respectively. These results were statistically significant difference at the confidence level of 95% (P<0.05 ). Mentha cordifolia Opiz. extract can give highly antibacterial activity because of the two major components of essential oil of this plant which are eugenol phenol and thymol. These two components are widely used to inhibit a great number of pathogenic bacteria. The results of this study also reveal the potential uses of the extracts of native medicinal plants in inhibiting pathogenic bacteria and can be developed for use as prevention for bacterial infections.


P.88-102

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Cytotoxic Alkaloids from the Root Bark of Zanthoxylum rhetsa

แอลคาลอยด์จากเปลือกรากมะข่วงที่แสดงฤทธิ์ความเป็นพิษต่อเซลล์มะเร็ง

พิชิต สุดตา* กานต์ หลินลาโภ และ จริยา ปันโป่ง

Eight known alkaloids were isolated from the root barks of Zanthoxylum rhetsa. Based on the spectroscopic data analysis and the comparison with previous spectral of reported alkaloids, their structures were established as dihydroavicine (1), dihydronitidine (2), paraensidimerine C (3), N-methylflindersine (4), 8-acetonyldihydroavicine (5), paraensidimerine A (6), 8-acetonyldihydronitidine (7), and akimmianine (8). Among them, alkaloids 3-6 were obtained for the first time from this plant. The cytotoxic evaluation of these alkaloids toward  three cancer cell lines, epidermoid carcinoma of oral cavity (KB), breast adenocarcinoma (MCF-7) and small cell lung cancer (NCI-H187) found that monomeric quinolinone alkaloid 4 exhibited effective cytotoxicity against NCI-H187 (IC50 0.536 μg/mL) and  KB (IC50  25.16 μg/mL) cells. Among benzophenanthridine alkaloids, compound 7 was proved to be more potent as an anticancer agent to all cancer cell lines and was approximately 126 folds greater than that of the standard drug ellipticine (IC50 3.14 μg/mL) to NCI-H187. The presented results demonstrate that alkaloids 4 and 7 can be recommended as appropriate lead structures for the design and synthesis of their analogs to improve efficacy.


P.103-110

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Utilization of Hydroponics Nutrient Solution to Replace Nutrient in Hippeastrum johnsonii Tissue Culture Media

การใช้สารละลายธาตุอาหารสำหรับปลูกพืชโดยไม่ใช้ดินทดแทนธาตุอาหารในสูตรอาหารเพาะเลี้ยงเนื้อเยื่อว่านสี่ทิศ

กิตติศักดิ์ โชติกเดชาณรงค์

Utilization of hydroponics nutrient solution to replace nutrient in Hippeastrum johnsonii tissue culture media were studied. The bulb scale explants of H. johnsonii were cultured on agar media containing hydroponic solutions of two stocks A and B each of the same concentrations of 1, 2, 3, 4 and 5 ml/L with 30 g/L of sucrose. The pH of the medium was adjusted to 5.7 and 7 g/L of agar was added before heating until all agar was dissolved. It was then allowed to cool to 60°C and 0.1 ml/L of haiter was added. The explants were incubated at 25±2°C with light condition 16 h per day for 6 weeks. The results showed that there were no significantly differences in shoot number shoot length and root number among bulb scale explants cultured at the concentration of 3, 4 and 5 ml/L of stock A and B hydroponics media and MS medium (p<0.05) indicating that hydroponics nutrient solution can be used as a replacement for essential nutrients in H. johnsonii tissue culture media.


P.111-123

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Resistance of Aspergillus flavus against Benzoic Acid and Sorbic Acid in Chili Paste (Num Prik Ta–Dang)

การต้านทานกรดเบนโซอิกและกรดซอร์บิกของ Aspergillus flavus ในน้ำพริกตาแดง

ยศยา ทุริสุทธิ์   อรรณพ ทัศนอุดม   ลัดดา วัฒนศิริธรรม   ฆรณี ตุ้ยเต็มวงศ์ และ วราภา มหากาญจนกุล*

Num Prik Ta Dang , a traditional chili paste, is a popular condiment among Thai consumer.  This product has a short shelf-life which common preservatives such as benzoate and/or sorbate are added by manufacturers, therefore often found these preservatives exceed the maximum limit according to food regulation. The aim of this study was to investigate the resistance of contaminated mold in Num Prik Ta Dang against benzoic acid and/or sorbic acid in order to recommend the proper use of these preservatives. Survey of 60 samples of Num Prik Ta Dang sold in 20 provinces of Central and Eastern part of Thailand was conducted. Results found that the pH value of chili paste ranged from 4.0–6.35, while aw value was 0.63–0.93. Benzoic acid and sorbic acid were added as 78% and 13%, ranging from 169–5,302 mg/kg and 2–1,760 mg/kg, respectively. Whereas 23 of 60 samples (40%) contained benzoic exceed the maximum limit (at 1000 mg/kg). High load of yeast and mold (95%, >102 CFU/g) and total bacteria (58%, >105 CFU/g) was found. Moreover pathogenic bacteria such as C. perfringens was found 21.7% (>102 CFU/g). Then Aspergillus flavus 0701, isolated from chili paste, were cultured on Potato Dextrose Agar adjusted pH at 4.5 and 5, and aw at 0.85 and 0.9. Isolate was inhibited by sorbic acid at concentration 800 mg/kg (pH 5.0 or 4.5, aw 0.90). At both level of pH when reduced aw to 0.85, the growth of A. flavus 0701 was inhibited completely by adding benzoic acid at 500 mg/kg. Using of both preservatives to prolong shelf-life of food depends on combination factors of mold strain, aw and pH of food. In this simulated conditions in food model results showed adding only sorbic acid was the best effective against preservative resistant mold, following by the combination of benzoic and sorbic acid, and lastly only benzoic acid added.


P.124-141

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Utilization of Medicinal Plants by Traditional Healers for the Treatment of Liver Diseases in Songkhla Province

การใช้พืชสมุนไพรรักษาโรคตับของหมอพื้นบ้านในจังหวัดสงขลา

จันทร์เพ็ญ ธรรมพร   เกศริน มณีนูน*   นิสิตา บำรุงวงศ์ และ มาลินี วงศ์นาวา

A study on the utilization of medicinal plants for treating liver diseases in Songkhla Province was carried out during 2012-2014. Five experienced traditional healers were interviewed by using semi-structured interviews and participant observation. Among the total 87 medicinal plant species collected, which belong to 78 genera of 44 families, the three most frequently represented families were Apiaceae, followed by Fabaceae and Phyllanthaceae. The underground plant parts were the most frequently used plant part. Decoction was the main mode of preparation and bitter plants were commonly used for making remedies for liver disease treatments. Eighteen traditional prescriptions were documented and the main administration of herbal remedies was oral route (15 prescriptions). Eight species, Capparis micracantha DC., Clerodendrum indicum (L.) Kuntze, Tiliacora triandra (Colebr.) Diels, Ficus racemosa L., Harrisonia perforata (Blanco) Merr., Aegle marmelos (L.) Corrêa ex Roxb., Terminalia chebula Retz., and Myristica fragrans Houtt., were frequently quoted by traditional healers and they were used as important ingredients of prescriptions for liver diseases. Interestingly, some species have never been tested for liver diseases and related biological activities, such as Anaxagorea luzonensis A. Gray, Capparis acutifolia Sweet and Caryota mitis Lour.


P.142-152

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Total phenolic and total flavonoid contents, free radical scavenging activity and tyrosinase inhibitory potential from the methanolic extracts of Cajanus cajan (L.) Millsp. and Acacia concinna (Willd.) DC. Flowers.

ปริมาณสารประกอบฟีนอลิกและฟลาโวนอยด์ ฤทธิ์ต้านอนุมูลอิสระ และฤทธิ์ยับยั้งเอนไซม์ไทโรซิเนสของสารสกัดเมทานอล จากดอกถั่วแระและดอกส้มป่อย

สุธิรา มณีฉาย* และ ประสบอร รินทอง

The present research was aimed to determine total phenolic and total flavonoid contents, antioxidant activity, tyrosinase inhibitory capacity of Cajanus cajan (Fabaceae) and Acacia concinna (Fabaceae) flowers. The methanolic crude extracts of C. cajan (CC) and A. concinna (AC) were prepared by reflux method. The results showed that total phenolic contents of CC and AC were 113.54±2.75 and 60.96±3.64 mg of gallic acid equivalent /g extract, respectively. The flavonoid contents were 0.22±0.03 and 0.98±0.01 mg of quercetin equivalent /g extract, respectively. Both extracts were also investigated their antioxidant activities using DPPH and ABTS assays. Based on DPPH method, IC50 of CC and AC were 0.66±0.03 and 0.94±0.02 mg/mL. For ABTS assay, IC50 of CC and AC were 0.60±0.02 and 0.84±0.01 mg/mL, respectively. The tyrosinase inhibitory activities of CC and AC were also determined. Their IC50 values were 2.21±0.16 and 1.91±0.09 mg/mL, respectively.


P.153-163

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Screening of bacteria and yeasts for transesterification biocatalyst in biodiesel production using waste cooking oil

การคัดเลือกแบคทีเรียและยีสต์เพื่อใช้เป็นตัวเร่งชีวภาพในปฏิกิริยา ทรานส์เอสเทอริฟิเคชันจากน้ำมันเหลือใช้ในครัวเรือนในการผลิตไบโอดีเซล

กิจสิทธิ์ พรหมสุทธิ์* มาริสา จาตุพรพิพัฒน์ และ อารี ฤทธิบูรณ์

This research emphasized on screening and morphological study of lipase-producing bacteria and yeasts isolated from soil in the area of oil industry as well as lipase-producing mutant yeast. The strains with high lipase activity were conducted to use as mixed culture for being as biocatalyst in biodiesel production. The results found that 8 strains of bacteria, 7 strains of wild type yeast, and 1 strain of mutant yeast were obtained from primary screening by culturing in solid media containing 1 mg/ml of rhodamine B and waste cooking oil as carbon source at 30 °C for 48 hr. The orange-pink colonies were selected and secondary screened in liquid media containing waste cooking oil as carbon source in order to determine for lipase activity. The results revealed that strain KPB8 (bacterium), KPY9 (wild type yeast), and G47 (mutant yeast) gave maximum lipase activity and had significantly value of 0.31, 0.34 and 0.4 U/mL, respectively at p£0.05. After that, they were subjected to examine as biocatalyst in transesterification by culturing as mixed culture in waste cooking oil and ethanol. The percentage of ester produced from reaction was calculated after analyzed the supernatant by gaschromatography mass spectrometry (GC-MS). The result showed that isolate KPB10, KPY9 and G47 had ability for being good catalysts in transesterification which gave rise the percentage of esters of 30.7, 12.2 and 42.9, respectively.


P.164-174

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Preparation of Platinum Catalysts on Titanium Dioxide Nanotubes for CO Oxidation Reaction

การเตรียมตัวเร่งปฏิกิริยาแพลทินัมบนไทเทเนียมไดออกไซด์แบบท่อนาโน สำหรับปฏิกิริยาออกซิเดชันของคาร์บอนมอนอกไซด์

ณัฐญา คุ้มทรัพย์*   เพียงพิศ กลิ่นหรั่น   ธงชัย กลิ่นหรั่น   ปราณี ศรีกอบัว และ สถาพร คำหอม

Titanium dioxide nanotubes (TNT) were prepared by hydrothermal method and were used as support materials for platinum catalysts. X-ray diffraction (XRD) analysis, Transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) surface area analysis and Atomic absorption spectroscopy (AAS) were used to characterize the prepared samples. The results indicated that the synthesized titanium dioxide nanotubes had a large specific surface area of 288 m2/g, with an average inner diameter of 10 nm and a length range of 150-200 nm. The platinum catalysts were prepared by two methods. First, the platinum nanoparticles were impregnated on the titanium dioxide nanotubes. Second, the platinum nanoparticles were impregnated on the titanium dioxide nanoparticles before the nanotubes process. The catalytic activity of platinum catalysts was tested in the CO oxidation reaction. The 1%Pt/TNT catalyst from the first method exhibited the highest catalytic activity with light-off temperature at about 133 °C because of good dispersion of platinum nanoparticles on surface support.


P.175-188

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Effects of Iron Species on Catalytic Performance for Phenol Hydroxylation of Fe-MCM-41

ผลของสปีชีส์เหล็กบน Fe-MCM-41 ต่อประสิทธิภาพการเร่ง ปฏิกิริยาฟีนอลไฮดรอกซิเลชัน

Waenkaew Pantupho   Krittanun Deekamwong   Sanchai Prayoonpokarach   Jatuporn Wittayakun   Sirinuch Loiha*

Catalysts with 5 wt% iron supported on MCM-41 were prepared by impregnation (5Fe-MCM-41_IMP) and mixed gel hydrothermal synthesis (5Fe-MCM-41_HYD). Both catalysts showed high crystallinity of regular hexagonal structure of MCM-41. Iron species in 5Fe-MCM-41_IMP were the magnetite or inverse spinel Fe3O4 whereas that in 5Fe-MCM-41_HYD was tetrahedral Fe(III) in the MCM-41 framework. Catalytic activity and selectivity for phenol hydroxylation of the catalysts were determined. A higher catalytic activity of 5Fe-MCM-41_HYD over 5Fe-MCM-41_IMP was observed. Catalytic selectivities in term of catechol to hydroquinone ratio were 70:30 and 60:40 for 5Fe-MCM-41_IMP and 5Fe-MCM-41_HYD, respectively. The selectivity to hydroquinone was improved by the presence of tetrahedral Fe(III) in the MCM-41 framework due to its low hydrophilicity. The Fe3O4 species on 5Fe-MCM-41_IMP was more selective to catechol and favorable for strong adsorption of phenol due to its high hydrophilicity leading to catalytic deactivation by carbon deposition.


P.189-200

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Removal of lead(II) ion in water by adsorbents from Pithecellobium dulce

การกำจัดไอออนตะกั่วในน้ำด้วยตัวดูดซับจากมะขามเทศ

Vanida Chairgulprasert*   Nuchtima Madlah   Rukaiyah Pohmueyae and Nurheedayah Madmanang

The removal of lead(II) ion in water by the adsorbents from the fruit peels and leaves of Pithecellobium dulce has been studied using a batch method. Four parameters, contact time, pH, initial lead concentration and adsorbent dose were optimised to maximise adsorption.  The maximum adsorption efficiency for the fruit peels was 90%, compared with 87% for the leaves. In both cases, the adsorption data followed second-order kinetics and fit the Freundlich isotherm. For the peels, the data were more effectively modelled using a simple Langmuir isotherm.


P.201-211

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Distribution of Seagrass (Enhalus acoroides) and Relationship with Environmental Factors at Kung Krabaen Bay, Chanthaburi Province

การกระจายของหญ้าคาทะเลที่มีความสัมพันธ์กับปัจจัยสิ่งแวดล้อม บริเวณอ่าวคุ้งกระเบน จังหวัดจันทบุรี

เบ็ญจมาศ ไพบูลย์กิจกุล*   ภูวดล จันทร์แสง และ ชลี ไพบูลย์กิจกุล

This research aimed to investigate distribution of seagrass Enhalus acoroides and relationship between distribution of seagrass, organic matter, soil texture and environmental parameter at Kung Krabaen Bay, Chanthaburi Province. Samples and environmental data had been collected on July 2014. Line transect had been used for data survey and collection.  Result of the study showed that E. acoroides had distributed at south part of the study area.  The average percentages of sand:silt:clay were 73:24:3.0, 71:26:3 and 70:27:3, respectively. The average of organic matters at eastern, central and western parts of study area were 0.85±0.41,  0.72±0.33 and 0.81±0.28%, respectively. The correction coefficients between distribution of seagrass and organic matter, distribution of seagrass and percentage of sand, distribution of seagrass and percentage of silt, distribution of seagrass and percentage of clay, distribution of seagrass and ORP and distribution of seagrass and pH were 0.0224, -0.17, 0.0295, 0.361, -0.0908 and 0.0878, respectively. Consequences of this study can applied for integrated management of seagrass and abundance of coastal ecosystem for maximum benefit of resources utilization at Kung Krabaen Bay of people in this area.


P.212-221

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The Effect of Land Use Changes on Landslide in the High Slope Area at Surat Thani Province

ผลของการเปลี่ยนแปลงการใช้ประโยชน์ที่ดินต่อการเกิดดินถล่ม ในพื้นที่สูงชัน จังหวัดสุราษฎร์ธานี

ณัฐณิชา ผ่องพุฒิ*   อรอนงค์ ผิวนิล   เกษม จันทร์แก้ว และ สุรชัย รัตนเสริมพงศ์

This research aimed to analyze the changes in land use and predict future land use by using IDRISI and Land Change Modeler to examine areas of landslide risk in the steep slope area in Surat Thani Province. The study found that, during the years 2000-2013, forest area had been decreased continuously, while area of para rubber plantations increased. Some areas of para rubber plantations were located on slopes steeper than 30 degrees, and had improper planting methods which were vulnerable to landslides. Moreover, an increase in residential areas were found during the years 2002-2005, and number of wells also raised during the years 2005-2007. There was a decrease in mixed orchard area; on the other hand, area of oil palm plantations had been increased in the year 2010. The projection of changes in land use of the year 2018 showed that the forest and mixed orchard areas will reduce. Conversely, the areas of oil palm and para rubber plantations, and residence will be increased. Mitigation of the impact of landslides caused by human action needs active actions for proper land utilization, and plants para rubber in the steep slope area under the principles of soil and water conservation.


P.222-236

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Comparisons of Opinions between Students Unwithdrawn and Withdrawn Calculus 1 of Thaksin University

การเปรียบเทียบความคิดเห็นของนิสิตมหาวิทยาลัยทักษิณ ระหว่างผู้ที่ไม่ถอนและถอนรายวิชาแคลคูลัส 1

วรางคณา กีรติวิบูลย์

Objective of this research was to compare the opinions between students unwithdrawn and withdrawn Calculus 1 of Thaksin University. The opinions were divided into nine aspects: learning achievement, lecturer, teaching behavior, classroom environment, curriculum, study field, educational institution, friends, and family. The sample used in this study was 455 undergraduate students of Thaksin University at the academic year 2013 who had registered Calculus 1 during academic years 2010 to 2012. The sample was obtained by circular stratified systematic sampling method and the data was collected by using questionnaire which had the reliability equal to 0.94. The statistics used in data analysis were frequency, percentage, mean, standard deviation, and Hotelling’s T2 test. The result indicated that all aspects of the opinions from Thaksin University’s students who did not withdraw Calculus 1 differed from the students who withdraw at the significance level 0.05.