Total phenolic content, total flavonoid content and radical scavenging activity from zingiber zerumbet rhizome using subcritical water extraction

Subcritical water extraction (SWE) is an alternative technique implemented water as a solvent. The objective of this work was to extract Zingiber zerumbet rhizome using SWE at a temperature range from 100ºC to 180ºC with duration from 5 to 25 min. The extracts were analysed for total phenolic content (TPC), total flavonoid content (TFC) and radical scavenging activity (RSA). Soxhlet extraction using ethanol was used for a comparison purpose. Results showed the highest TPC and TFC was obtained at 180ºC and 25 min extraction, with the yield of 18.52 mg GAE/gDW and 2.34 mg QE/gDW of rhizome for TPC and TFC, respectively. RSA at peak of 83.9 % inhibition at the condition of 180ºC and 10 min extraction. In comparison to Soxhlet extraction, the extract after SWE gives the highest amount of TPC and RSA. However, the values for TFC are lower as compared to ethanolic extract. Therefore, SWE process for Zingiber zerumbet extract is favourable for higher TPC and RSA. A direct linear correlation between the RSA with the TPC and TFC of the extracts shows that a strong correlation was observed between TPC and the RSA with the R2 obtained was 0.910 as compared to moderate correlation (R2=0.785) perceived in TFC. Thus, it shows higher radical scavenging activity in Zingiber zerumbet was contributed by phenolic content as compared to its flavonoid content. In overall, SWE is a potential alternative extraction process that should be further explored

Subcritical water extraction (SWE) of Zingiber zerumbet using two level full factorial design

Zingiber zerumbet was reported to has chemo preventive effects and was suggested as one of the therapeutic treatments for cancer. In this study, Z. zerumbet was extracted using subcritical water extraction (SWE) by employing two level full factorial design. 2k full factorial design was employed using 18 runs with 10 repeats in central points. The independent variables factors were temperature (100-150°C), time (10-30 minutes) and material ratio (1:10 and 1:20 g/ml) for the evaluation of highest zerumbone concentration and overall yield of extracted Z. zerumbet. Effects of extraction temperature and time were found to be significant on all responses with p-value <0.05. However, the material ratio only gave significant effect on the zerumbone concentration and less significant on the yield. In addition, the value of curvature was found to be significant, thus indicating the relation between the independent variables and the response was linear. Therefore, it was found that the concentration of zerumbone and yield from Z. zerumbet extracted by SWE were significantly affected by temperature and time of extraction

RNA Interference (RNAi) for plants

As we are facing global population development, strategies are required to improve agricultural production in the battle against hunger and poverty. Agricultural biotechnology provides a powerful method in combination of conventional breeding, new innovations and enhanced management of resources which improves the productivity of livestock, aquaculture, and crops. After the finding of RNA interference (RNAi), researchers have made considerable growth in improving this remarkable crop especially in defence technology. RNA interference is a vital plant growth, development and reaction regulator to various types of stresses. This technology leads to higher efficiency and potency of gene silencing, thus becoming the highly promising technology for crop improvements at a rapid rate with some advantages. Nowadays, RNAi has been widely used for the improvement in agricultural biotechnology and seems to be applicable and commercialized in other fields too

Gold nanoparticles from plant materials: green extraction, biological synthesis and its beneficials properties for cosmeceutical applications

Green technologies have become trends among researchers and it is developing as the current demand is increased towards products that are processed through green technologies. In this regard, green extraction and green synthesis of gold nanoparticles (GNPs) from plants are presented and discussed. Rapid development in green extraction makes the researchers are competing in providing the best extraction techniques which will use safe extracting solvent, low energy consumption, and did not release hazardous materials as residues of the processes. The same thing goes for the green synthesis of GNPs, plant extracts are used as reducing agent and it does not release any hazardous residues as compared to chemical synthesized GNPs. The application of the GNPs in this paper is reviewed on their properties that are beneficial for cosmeceutical applications. Even though the application of GNPs in the cosmeceutical application in research papers is relatively unexplored, but it has a high potential to be studied since there is existing research that recognizes the properties played by GNPs. The properties that are mostly studied by researchers are an antioxidant, anti-inflammatory, and antibacterial activity that is found to be advantageous in the production of cosmeceutical products

Total phenolic, flavonoid content and antioxidant activity of Clinacanthus nutans leaves by water-based ultrasonic assisted extraction

Clinacanthus nutans (C. nutans)is a prominent herb species that widely cultivated in Southeast Asia region. The effect of water-based ultrasonic assisted extraction at various temperature (30 to 60 °C) and time (5 to 30 minutes) on the total phenolic, flavonoid content and antioxidant activity in C. nutansleaves extract was investigated. Acquired extract was quantified for its total phenolic, flavonoid content and antioxidant activity by Folin-Ciocalteu, aluminium chloride test and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay, respectively. The result has revealed that the highest temperature led to the degradation of bioactive compound in C. nutansleaves. The highest phenolic content and antioxidant activity achieved at 55 °C and 25 minutes with 13.87 ± 0.15 mg gallic acid g-1dry sample and 52.88 ± 3.91% inhibition, respectively. Meanwhile, greatest flavonoid content was obtained for 12.25 ± 1.01 mg quercetin g-1of dry sample at 55 °C and 15 minutes of extraction. From this study, it was shown that C. nutansextraction has gained benefit from ultrasonic assisted extraction and has possibilities of being used for the herbs utilisation of beneficial food materials, nutraceuticals and pharmaceuticals at manufacturing industry

Leveraging the Human Capital Values and University's Support on Knowledge Transfer Program for Community in Malaysia

Community transformation based on economic empowerment is one of most challenging issues faced by the government in ensuring continuous future development in Malaysia. The aspiration to shift from middle-income to high-income community required higher commitment from various stakeholders. Strengthening human capital value required community transformation which reflected in high value-added and knowledge-intensive activities that considered as one of the greatest available resources to heighten the Malaysia strategy in achieving continuous community development. Knowledge Transfer (KT) is declared in the Malaysian government blueprint as one of the program that aims to support the government's efforts to eradicate poverty and embracing community development through the transferring of knowledge, translating theories into practice and skills possess by the academia and graduate interns in the universities to the community at large. A total of 458 knowledge transfer projects were approved by the Malaysian government since 2011 to 2016 and out of that numbers, there are 352 projects under the flagship of community. Due the importance of the community development to the nation at large, the study attempts to investigate the effect of human capital values and University's support on the community development success based on a perception and experience of graduate intern (GI) in handling their KTP projects. Data were collected through structured questionnaires and regression analysis is conducted in this study. The findings reveal that human capital value and university's support are positively related to the community development performance. The result indicates the importance of casting of human capital value and affirmative support from the higher institution of learning (HIL) as an authorized agency in ensuring the success of KTP project

Comparison and characterization of different types of durian husk as activated carbon

In this study, characterization of activated carbon (AC) produced from durian husk by chemical activation technique using potassium hydroxide (KOH) as activating agent. Three types of durian husk used were Durian D-2 (DD-2), Durian Kampung (DK) and Duriang Kacing Baju (DKB). All of these durians husk are then carbonized and activated. The particle size of AC is sieved between 300 - 600 mm. The AC is then characterised according to proximate analysis and chemical properties. The proximate analysis is including moisture content, ash content, volatile matter and fixed carbon. The elemental analysis is also done. Commercial adsorbent silica gel was compared with carbon produced by using iodine titration. All types of durian husk shows difference values in physical analysis and almost same characteristics in chemical analysis

Degradation of persistent endosulfan by isolated actinomycetes and Rhodococcuss jostii, RHA1

The property of organochlorine endosulfan which is persistent and toxic can cause environmental pollution and pose human health and has raised concern worldwide. Hence, biodegradation serves as promising tool in overcoming the problem of pesticides pollution. The effective approach of removal of endosulfan from the environment is by using Gram-positive microorganisms such as actinomycetes, predominant microorganisms found in soil habitat are less exploited and studied in biodegradation of endosulfan. The diverse metabolic diversity and unique enzymatic capabilities of actinomycetes has gained interest in biodegradation to remove the endosulfan from the environment. This study aims to isolate indigenous actinomycetes from soil habitat and screening the ability of isolated actinomycetes to degrade the endosulfan. Cameron Highland where intensive agricultural activities were carried out was chosen as the sampling site for isolation of actinomycetes that could have potential in degradation of endosulfan. Screening of the ability of endosulfan degradation by isolated actinomycetes in sulphur free broth culture and followed by determination by residual endosulfan by using GC-ECD analysis which is sensitive and specific assay in detecting the endosulfan

Induction condition of secondary metabolites production in soil actinomycetes, rhodococcus jostii RHA1

Rhodococcus jostii RHA1 is a potent polychlorinated biphenyl-degrading soil actinomycete that catabolizes a wide range of compounds and represents a genus of considerable chemical and industrial interest. Genome of RHA1 contains nonribosomal peptide synthase (NRPS) genes, and polyketide synthase (PKS) genes, providing evidence that RHA1 harbor an extensive secondary metabolism as same as other actinomycetes. To elucidate R. jostii RHA1 may produce any kinds of secondary metabolites, induction condition of these secondary metabolite production genes were investigated. Type I, type III, PKS-NRPS hybrid located on chromosome, and NRPSs located on plasmid were typically induced on solid medium with specific nutrient or environment condition. On the other hands, type II PKSs located on chromosome were mainly induced on liquid medium with specific condition. These results indicated that secondary metabolites induced on specific condition on solid or liquid medium by RHA1 might play a key role of surviving under severe environmental condition

Extraction of hemicellulose from oil palm biomass using subcritical water extraction to produce value-added product or fine chemicals

Renewable energy sources such as wind, hydro, solar, hydrogen, nuclear and biomass are various type of alternatives energy available to replace non-renewable fossil fuels. The total oil palm biomass produced by Malaysia alone is about 53.04 million tonnes (mt), which include 17.08 mt of empty fruit bunches, 9.66 mt of fibre, 5.2 mt of shell, 12.9 and 8.2 mt of fronds and trunks. This research will focused on the production of value-added product or fine chemicals based on extraction of xylose and xylooligosaccharides from hemicellulose of lignocellulosic biomass. As preliminary results, the pH value, TOC value and total sugar concentration were determined