The seed, skin and whole grape extract of the red grape cultivar Shiraz, which is widely cultivated in Northeastern Thailand, were investigated. Total phenolic, total flavonoid and total monomeric anthocyanin content ranged from 48.04 to 116.73 g GAE/100g db (dry weight base), 74.82 to 258.69 mg CE/g db, and 5.06 to 55.45 mg/100g db, respectively. Dimeric procyanidin (119.56-484.08 mg/100g db), (+)-catechin (52.30-231.92 mg/100g db), (-)-epicatechin (27.92-174.10 mg/100g db), and gallic acid (4.42-27.80 mg/100g db) were found to be the main flavanols that were present in the seed. Rutin and trans-resveratrol were present in amounts of between 21.13 and 40.05 and 2.85 and 3.60 mg/100g db respectively. All extracts showed remarkable DPPH radical-scavenging activity (EC 50 ), ranging from 0.47 to 2.10 µg/mL. Methanolic extract from the seed and skin were also active against all Gram-positive bacteria, but these exerted less of an inhibiting effect on the growth of the tested Gram-negative bacteria. The activity of the methanolic extract of the seed was effective against B. cereus ATCC 11778, B. subtilis ATCC 6633 and S. faecalis TISTR 459.

Abstract. Saisor N, Prathepha P, Saensouk S. 2021. Ethnobotanical study and utilization of plants in Khok Nhong Phok forest, Kosum Phisai District, Northeastern Thailand. Biodiversitas 22: 4336-4348. The present study was conducted in Khok Nhong Phok forest, Kosum Phisai District, Maha Sarakham Province, Northeastern Thailand. The forest was surrounded by communities where traditional knowledge has been inherited in the utilization of plants which may disappear over time due to the development of medicinal science and technology. The primary is to study the traditional knowledge in ethnobotanical, collect information about the utilization of plants, and provide the scientific name as the basis for future studies. Data were collected through open-ends interviewing with 30 villagers living in villages around the forest area about their local name, utilization of plants in all 3 aspects, including plants used as food, medicine, and plants used to build houses including parts of plants used. Plant materials and photographs were collected from January to December 2019. Altogether 101 plant species were recorded belonging to 52 families, divided into 3 groups of utilization according to traditional knowledge including 50 species of food plants, 69 species of medicinal plants, and 42 species used for housing, appliances, and fuel. In this study, some plants with more than one type of utilization showed that they were valuable to local people in terms of their uses, and such information can be used as a guideline for the conservation of plant resources in the area to show the importance of cherishing, and maintain valuable resources in the area to remain for future generations.

This study was designed to determine the anthocyanin cyanidin-3-glucoside content and antioxidant activity of rice varieties under salinity stress. Two classes of Thai rice lines: cyanic (Riceberry, Kham, and Khamdoisaket) and acyanic (KDML 105, Sinlek, were hydroponically grown. Seedlings were grown for 16 days and were supplied with salinity nutrient solution with 0 (control) and 60 mM NaCl for 11 days. The total phenolic content and the antioxidant activity, including 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging, ferric reducing antioxidant power, and lipid peroxidation were also determined by colorimetric assay. Anthocyanin pigment cyanidin-3-glucoside was quantified by high performance liquid chromatography. The results show that salinity stress in Khamdoisaket and KDML 105 cultivars significantly (p < 0.05) increased the total phenolic content, antioxidant activity, and cyanidin-3-glucoside content. Riceberry, Kham, and Sinlek cultivars, showed a moderate increase. The salt tolerant variety, BC2F7#62-56, showed only a slight but not significant increase in antioxidant activity and virtually unchanged lipid peroxidation, total phenolic content, and anthocyanin cyanidin-3-glucoside content under salinity stress. These results suggest that the increased total phenolic content, antioxidant activity, and anthocyanin cyanidin-3-glucoside content in rice seedling might be a protection mechanism against salinity stress. BC2F7#62-56 seems to have potential tolerance to salinity stress. This capability could be related to unchanged antioxidant activities, lipid peroxidation, total phenolic content, and anthocyanin cyanidin-3-glucoside content.

Weedy rice (Oryza sativa f. spontanea) is a problematic weed in the Thai Hom Mali rice production areas of Thung Kula Ronghai in north-eastern Thailand.There is a great need to initiate studies of weedy rice populations in order to perform basic studies to learn about the seed morphology and genetic diversity. The aims of this study were to determine the seed morphological traits and amylose content and to evaluate the genetic variation, based on the polymorphisms of nuclear and chloroplast DNA, of weedy rice.The seeds and flag leaves were collected from a total of 125 weedy rice plants at six rice fields in the region. For the samples, four morphological traits, the amylose content, and the chloroplast identity (ID) sequence and microsatellite genotypes at the waxy locus were determined.The weedy rice that was collected from the Thung Kula Ronghai region varied considerably in its amylose content and both the seed morphology and genotypes. Some of the weedy rice shared the common microsatellite alleles and chloroplast ID sequence with Thai Hom Mali and wild rice, Oryza rufipogon, indicating that the weedy rice in this region might originate from the introgression between cultivated rice and O. rufipogon, which often takes place in nature, mostly in a one-way process from cultivated rice to O. rufipogon.

The identification of a number of cDNA sequences at the splice sites of Waxy (Wx) gene in rice endosperm point to the variation of gene expression associated with the G to T mutation at the 5' splice site of intron 1 and the alternative splicing produces variants transcripts by shortening. As consequence, variation of amylose content in this tissue. To determine whether the splicing type of Wx genes are also found in rice endosperm of Thai rice cultivars, cDNA of the gene have been isolated by using RT-PCR and sequenced. Analysis of the twenty-five cDNA clones led to the identification of the splicing pattern of the gene, four cryptic splice sites was found in cDNA sequences of low-amylose cultivars (<20%), while two cryptic splice sites of intermediate (20-25%) and high (>25%) amylose cultivars were characterized. The alternatively spliced transcripts were observed in much higher proportion in low amylose cultivars than that in intermediate and high amylose cultivars. These findings raise a possibility explanation that the degree of amylose content in non-glutinous rice cultivars may reflect to the amount of efficiently spliced transcripts.