Antibacterials and phytochemicals investigations of Chromolaenaodorata (L.F.) King and Robinson (asteraceae) from Sabah, Malaysia

Antimicrobial properties and phytochemical constituents in leaf extract of Chromolaenaodorata was evaluated in this study. C. odorataleaves were subjected to liquid-liquid extraction by using methanol, hexane, ethyl acetate, chloroform, buthanol and water. All extract partitions were tested for antibacterial activity against five Gram positive and Gram negative bacteria by using disc diffusion method. Crude methanolic extract (CME), ethyl acetate extract (EAE) and chloroform extract (CE) showed good antibacterial properties against the tested bacterial strains. However, only the CE was further separated using silica column chromatography. About 10 semi purified fractions was obtained and fraction 2 (F2) showed consistent inhibitory zones against all bacterial tested. Phytochemical investigations on the extract partitions and fractions showed the presence of alkaloids, flavonoids, tannins, polyphenols, saponins and triterpenoids. Fraction F2 was subjected to GC-MS analysis to characterised the bioactive compounds. The GC-MS spectral data has identified 10 major compounds which are hexachloro-ethane, n-nonylaldehyde, methyl-4-oxooctanoate, longiverbenone, 2-butenal,2-methyl-4-(2,6,6-trimethyl-1-cyclohexen-1-yl), neophytadiene, phytol, dihydro-neoclovene, 2,6-ditert-butylquinone and aromadendren

Growth Characteristics and Production of Physalins from Physalis minima Hairy Roots in Shake Flasks

This report described the growth characteristics and production of physalins from Physalis minima hairy roots in shake fl ask culture. The presence of lateral branches in the inoculum had a negligible effect on the fi nal root biomass dry weight (DW), specifi c growth rate (μ), doubling time (td) and production of physalins. However, excising the primary and lateral root tips reduced μ and the total root length but not the fi nal biomass. Mature root tissues were observed to accumulate more physalin B and F (1.55 and 3.74 mg.g-1 DW, respectively) compared to the root tips (0.65 and 1.47 mg.g-1 DW, respectively). Increasing the number of root tips from 2 to 12 and the medium volume signifi cantly reduced μ and extended td. Decreasing the medium volume with a small number of inocula reduced td, improved the biomass and production of physalins and μ. Using a 100 mL fl ask, four root tips cultured in 25 mL medium provided the optimum conditions for biomass (0.24 g DW) and production of physalins (1.68–3.5 mg.g-1 DW)

Effects of cooking on toxins levels and influence of food additives on toxins level in food products

Cooking is a process that could reduce the contamination level of toxic chemicals such polyaromatic hydrocarbons (PAHs) in several foodstuffs. However, this effect depends largely on the cooking process (grilling or frying), cooking material selection (charcoal, gas or wood), type of toxicant and the specific food item. This review discussed in detail pertaining to the effect of cooking and addition of food additives on the toxicant levels in foodstuff

Effect of growth regulators and explant orientation on shoot tip culture of Borneo endemic orchid, Dimorphorchis lowii

Multiple shoots were induced from the shoot tip explants derived from the in vitro grown seedlings of an endangered and horticultural important epiphyte orchid, Dimorphorchis lowii. Shoot tip explants were cultured vertically and/or horizontally on solidified Knudson C media (KC) added with various concentrations of Kinetin (Kn) and 6- Benzylaminopurine (BAP) for shoots multiplication. Shoots were initiated after 4 weeks of culture, and the highest number of healthy shoots (5.05 shoots per explant) was observed in 2.0 mg/l Kinetin (Kn), when the explant placed horizontally. Regenerated shoots were root-induced in KC medium with various concentrations and combinations of Naphthalene acetic acid (NAA), Indole acetic acid (IAA) and Indole butyric acid (IBA). Shoots cultured on medium with 1.0 mg/l IAA and 0.5 mg/l IBA was the most appropriate combination for rooting. Rooted plantlets were transferred in a medium mixture containing coco peat and sphagnum moss (2:1). After 2 months, 78% of plants survived when transferred to the glasshouse. This is the first report for in vitro propagation of D. lowii through shoot tip culture. The protocol developed can be utilized for both large-scale plant production and germplasm conservation of this specie

Primary screening for natural inhibitors against eukaryotic signal transduction from local medicinal plants in Sabah, Malaysia

Studies on eukaryotic signal transduction pathways have led to a variety of potential molecular targets for cancer therapy including Mitogen-activated Protein Kinase Kinase 1 (MKK1), Glycogen Synthase Kinase 3ß (GSK-3ß) and Type 1 Protein Phosphatase (PP1). The protein kinases and phosphatases in the signal transduction pathways play a vital role in mitogen activated protein (MAP) kinase signal transduction, tumorigenesis, apoptosis, and cancer metastasis. In this study, enetically engineered yeast strains were used as a model in the search for potential inhibitors against these signalling elements. Eleven species of medicinal plants were selected from various locations in Sabah, Malaysia, extracted and tested against MKK, GSK-3ß and PP1. Preliminary results showed the presence of potential MKK1 inhibitors in the crude extracts of Alphitonia excelsa, Cordyline terminalis and Tinospora crispa. However, no inhibitor was found against GSK-3ß and PP1. The crude extracts of Cordyline terminalis was further fractionated using a bioassay guided fractionation and four partially pure active fractions were isolated

Effect of yeast extract and coconut water on protocorm proliferation and growth development of Dimorphorchis rossii

Dimorphorchis rossii is an epiphyte orchid that endemic to Borneo, specifically Sabah. Forest clearance and fires on its natural habitat and illegal collection by local people contributed to the extinction of this orchid. In attempt to preserve this exquisite orchid, an efficient propagation protocol was established by means of plant tissue culture. The main objective of this study was to determine the effect of coconut water (CW) and yeast extract (YE) on protocorm proliferation and growth development. The protocorms used in this study were obtained from in vitro seed germination of Dimorphorchis rossii. Protocorms were cultured on Murashige and Skoog basal medium treated with 10%, 15% and 20% (v/v) CW or 0.1%, 0.2% and 0.3% (w/v) YE and grown under 16 hour light at 25±2°C for 130 days of culture. The pH of the media adjusted to 5.7. Maximum protocorm proliferation (41.67±0.51%) was observed on 0.2% (w/v) YE, and followed by 0.3% (w/v) YE (31.25±0.48%) after 130 days of culture. New protocorms produced in both complex additives are 1.94±0.35 and 1.50±0.02, respectively. However, 0.1% (w/v) YE recorded the highest average number of new protocorms (3.00±0.08). Meanwhile, protocorms grown on medium containing 10% (v/v) CW promoted the best complex additive for protocorms developed to seedlings with 78.33±0.42% and 66.67±0.48% of the explants produced leaf and root respectively. This medium also recorded the highest length of leaf (3.43±0.46mm) among other treatments. Maximum number of leaf (6.28±0.90) and length of root (3.71±0.42) were obtained on medium treated with 15% (v/v) CW. As can be seen in the pattern of the protocorm proliferation and growth development, it can be concluded that YE is preferred most for protocorm proliferation, while CW is for protocorm growth development to seedlings

Asymbiotic germination and seedling development of dimorphics lowii (orchidaceae)

Dimorphorchis lowii, a threatened Borneo endemic epiphytic orchid, is gradually becoming rare due to over collecting and habitat disturbance. Therefore this study was carried out to obtain in vitro propagation through asymbiotic seed germination and seedling development by optimizing capsule maturity, nutrients requirements and light conditions before introduce back to its natural habitat for conservation purposes. Capsules were collected at 100, 150 and 170 days through hand-pollination. The seeds were germinated on Murashige and Skoog (MS), Knudson C (KC) and Vacin and Went (VW) media added with 10% additives (coconut water, potato homogenate and tomato juice) under light and dark conditions. Seeds from 150 days old capsule grow on VW medium added with potato homogenate under light condition were observed to be an optimum condition with higher germination percentage as compare to other treatments. Seeds started to germinate by swollen of embryo (8 days) before the testa were ruptured at 23 days and further developed into mature protocorm at 33 days. Seeds with 4 leaves and 5 roots were ready for hardening process within 200 days. A successful developed system for in vitro propagation will contribute to the development of a sustainable management program for D. lowii in Sabah, Malaysia

Embryogenic callus induction from leaf tip explants and protocorm-like body formation and shoot proliferation of dimorphorchis lowii: Borneon endemic orchid

Dimorphorchis lowii is a rare epiphytic orchid endemic to Borneo and very popular due to its ornamental value. For the purpose of mass propagation, procedures for in vitro propagation through callus were developed. The objectives of this study were to determine the effects of plant growth regulators (PGRs) on callus induction from leaf tip explant and the effects of complex additives on PLBs formation and shoot development. The best combination of PGR was 3.0 mg L-1 Thidiazuron (TDZ) with 0.046 mg L-1 NAA supplemented in half-strength medium (½ MS) (Murashige & Skoog, 1962). The percentage of survival and callus formation obtained were 96.0 % ± 19.8 and 52.0 % ± 16.5 respectively. Maximum shoot proliferation from PLBs was observed in Knudson C (KC) medium enriched with 15 % (v/v) coconut water. In this treatment, 10.2 ± 6.2 shoots were produced from one callus explant. Shoots were rooted on KC medium containing 15 % (v/v) coconut water and transferred in a medium mixture containing sphagnum moss, charcoal, brick and coco peat with the ratio of 1:1:1:1. After 2 months being acclimatized in the glasshouse, 78 % of plantlets survived. Histology observations showed that embryogenic callus derived from leaf tip explants might originate from epidermis and mesophyll cells and was capable of developing into complete plantlets

In vitro seed germination of Coelogyne asperata Lindl. (Orchidaceae)

A protocol for in vitro seed germination of Coelogyne asperata Lindl. has been established successfully. Immature seeds from 182 days old capsule were cultured on three different basal media; Murashige and Skoog (MS), Knudson C (KC), and Vacin and Went (VW) and maintained under continuous light at 25 ± 2 ˚C. After 30 days of culture (DAC), more than 90% of seeds were germinated on KC and VW media and about 84% of seeds germinated on MS medium. The incorporation of organic additives, including coconut water, potato homogenate and tomato juice each at 10% (v/v) in KC medium was tested to determine their effect on seed germination of C. asperata. The result revealed that KC basal medium alone without addition of organic additives promoted over 90% of seed germination at 30 DAC. Therefore, the protocol of using standard KC basal medium for C. asperata seeds germination could be suggested for mass propagation and conservation of this wild scented orchid