Volatile compounds in the peel of calamansi (Citrus microcarpa) from Malaysia, the Philippines and Vietnam were extracted with dichloromethane and hexane, and then analysed by gas chromatography-mass spectroscopy/flame ionisation detector. Seventy-nine compounds representing >98% of the volatiles were identified. Across the three geographical sources, a relatively small proportion of potent oxygenated compounds was significantly different, exemplified by the highest amount of methyl N-methylanthranilate in Malaysian calamansi peel. Principal component analysis and canonical discriminant analysis were applied to interpret the complex volatile compounds in the calamansi peel extracts, and to verify the discrimination among the different origins. In addition, four common hydroxycinnamic acids (caffeic, p-coumaric, ferulic and sinapic acids) were determined in the methanolic extracts of calamansi peel using ultra-fast liquid chromatography coupled to photodiode array detector. The Philippines calamansi peel contained the highest amount of total phenolic acids. In addition, p-Coumaric acid was the dominant free phenolic acids, whereas ferulic acid was the main bound phenolic acid.
The constituents in a food emulsion interact with each other, either physically or chemically, determining the overall physico-chemical and organoleptic properties of the final product. Thus, the main objective of present study was to investigate the effect of emulsion components on beverage emulsion properties.
Solid-phase microextraction (SPME) coupled to gas chromatography has been applied for the headspace analysis (HS) of 12 target flavour compounds in a model orange beverage emulsion. The main volatile flavour compounds studied were: acetaldehyde, ethyl acetate, alpha-pinene, ethyl butyrate, beta-pinene, myrcene, limonene, gamma-terpinene, octanal, decanal, linalool and citral (neral plus geranial). After screening the fibre type, the effect of other HS-SPME variables such as adsorption temperature (25-55 degrees C), extraction time (10-40 min), sample concentration (1-100% w/w), sample amount (5-10 g) and salt amount (0-30% w/w) were determined using a two-level fractional factorial design (2(5-2)) that was expanded further to a central composite design. It was found that an extraction process using a carboxen-polydimethylsiloxane fibre coating at 15 masculineC for 50 min with 5 g of diluted emulsion 1% (w/w) and 30% (w/w) of sodium chloride under stirring mode resulted in the highest HS extraction efficiency. For all volatile flavour compounds, the linearity values were accurate in the concentration ranges studied (r(2) > 0.97). Average recoveries that ranged from 90.3 to 124.8% showed a good accuracy for the optimised method. The relative standard deviation for six replicates of all volatile flavour compounds was found to be less than 15%. For all volatile flavour compounds, the limit of detection ranged from 0.20 to 1.69 mg/L.
This paper focuses on the evaluation of the k0 method of instrumental neutron activation analysis in biological materials. The method has been applied in multielement analysis of human hair standard reference materials from IAEA, No. 085, No. 086 and from NIES (National Institute for Environmental Sciences) No. 5. Hair samples from people resident in different parts of Malaysia, in addition to a sample from Japan, were analyzed. In addition, human kidney stones from members of the Malaysian population have been analyzed for minor and trace elements. More than 25 elements have been determined. The samples were irradiated in the rotary rack (Lazy Susan) at the TRIGA Mark II reactor of the Malaysian Institute for Nuclear Technology and Research (MINT). The accuracy of the method was ascertained by analysis of other reference materials, including 1573 tomato leaves and 1572 citrus leaves. In this method the deviation of the 1/E1+ alpha epithermal neutron flux distribution from the 1/E law (P/T ratio) for true coincidence effects of the gamma-ray cascade and the HPGe detector efficiency were determined and corrected for.
This paper investigates the importance of loading and treatment with a vitrification solution on the survival of Citrus madurensis embryonic axes cryopreserved using a vitrification protocol. Among the seven different loading solutions tested, the solution containing 2 M glycerol + 0.4 M sucrose was the most efficient. Of the six vitrification solutions tested, the PVS2 vitrification solution, applied for 20 min at 25 degree C or for 60 min at 0 degree C, ensured the highest survival. A three-step vitrification protocol, involving the treatment of embryonic axes at 0 degree C with half strength PVS2 solution for 20 min then with full strength PVS2 for an additional 40 min was more efficient than a two-step protocol that involved treatment of axes directly with full strength PVS2 solution for 60 min. After rapid immersion in liquid nitrogen, rapid rewarming, unloading in a 1.2 M sucrose solution for 20 min, culture on solid medium with 0.3 M sucrose for 1 day and growth recovery for 4 weeks on standard medium, survival of C. madurensis embryonic axes reached 85 % following the three-step process, compared with 70 % for the two-step process.
In this paper, we demonstrate that C. madurensis embryonic axes can withstand cryopreservation using the encapsulation-dehydration technique. Up to 57.5 % survival was achieved using a standard encapsulation-dehydration protocol, which included pregrowth of encapsulated axes for 16 h in medium containing 0.8 M sucrose + 1 M glycerol, desiccation of beads to around 30 % moisture content (fresh weight basis) followed by rapid freezing. A slightly higher survival percentage (65 %) was obtained using a modified encapsulation-dehydration protocol, which included pretreatment of axes with 2 M glycerol + 0.6 M sucrose for 1 h, concomitantly with their encapsulation in 3 % calcium alginate beads, followed by desiccation of the beads to around 30 % moisture content.
The role of pregrowth and preculture treatments in terms of both medium composition and exposure duration on survival of embryonic axes of Citrus madurensis after cryopreservation using the vitrification procedure was investigated. The optimal pregrowth treatment for excised embryonic axes was a 3-day treatment with 0.1M sucrose. Preculture was also essential in increasing survival after cryopreservation. Among the various media and treatment durations evaluated, a 24h-preculture of embryonic axes on medium with 0.3M sucrose and 0.5M glycerol was found to be optimal. Using these pregrowth and preculture conditions followed by treatment at 25 degrees C for 20 min each with a loading solution (0.4M sucrose + 2.0M glycerol) and then the PVS2 vitrification solution, direct immersion in liquid nitrogen, rapid rewarming, unloading in a 1.2M sucrose solution for 20 min and transfer of embryonic axes on recovery medium, 82.5% survival and regrowth without intermediary callus formation were obtained with C. madurensis embryonic axes.
Colorectal cancer is the second leading cause of cancer-related deaths in the United States. Recent studies prove that though chemotherapeutic agents are being used for the treatment of colon cancer, they become non-effective when the cancer progresses to an invasive stage. Since consumption of certain dietary agents has been linked with various cancers, fruit juices have been investigated for their consistently protective effect against colon cancer. The unique biochemical composition of fruit juices is responsible for their anticancer properties. In this review, the chemo-preventive effect of fruit juices such as pomegranate and citrus juices against colon cancer are discussed. For this purpose, the bioavailability, in vitro and in vivo effects of these fruit juices on colorectal cancer are highlighted. Moreover, there is a scarcity of studies involving human trials to estimate the preventive nature of these juices against colon cancer. This review will support the need for more preclinical tests with these crude juices and their constituents in different colorectal cancer cell lines and also some epidemiological studies in order to have a better understanding and promote pomegranate and citrus juices as crusaders against colon cancer.
Rhipicephalus (Boophilus) microplus serves as an important ectoparasite of livestock and a vector of several pathogens resulting in diseases, subsequently affecting the agricultural field as well as the economy. The extensive use of synthetic acaricides is known to cause resistance over time and therefore a much safer, effective and environmentally friendly alternative to overcome tick infestation should be implemented. Larval immersion tests (LIT) were done to evaluate the effects of Citrus hystrix (Family: Rutaceae) and Cymbopogon citratus (Family: Poaceae) essential oils (EOs) for their individual and combined (1:1) acaricidal activity against the cattle tick. Results showed that LC50 and LC90 values in 24 and 48 hours for Cit. hystrix EO were 11.98% and 24.84%, and 10.95% and 21.71% respectively. LC50 and LC90 values for Cym. citratus EO were 1.21% and 6.28%, and 1.05% and 6.12% respectively. The mixture of EOs from two plants in 1:1 ratio (Cit. hystrix 50%: Cym. citratus 50%) was found to exhibit antagonistic effect (synergistic factor < 1). The 24 hours and 48 hours LC50 and LC90 values for combined EOs were 1.52% and 2.84%, and 1.50% and 2.76% respectively. Individual and combined essential oils were subjected to qualitative analysis using gas chromatography-mass spectrometry (GC-MS) to screen the chemical components present in EOs. Our results showed that the combination of Cit. hystrix and Cym. citratus at 1:1 ratio resulted in an antagonistic effect and the use of Cym. citratus alone is more toxic to R. (B.) microplus, making it a better alternative to chemical based acaricide.
It is said that the backbone of Indian economy is agriculture. The contribution of the agriculture sector to the national GDP (Gross Domestic Products) was 14.6% in the year 2010. To attain a growth rate equivalent to that of industry (viz., about 9%), it is highly mandatory for Indian agriculture to modernize and use automation at various stages of cultivation and post-harvesting techniques. The use of computers in assessing the quality of fruits is one of the major activities in post-harvesting technology. As of now, this assessment is majorly done manually, except for a few fruits. Currently, the fruit quality assessment by machine vision in India is still at research level. Major research has been carried out in countries like China, Malaysia, UK, and Netherlands. To suit the Indian market and psychology of Indian farmers, it is necessary to develop indigenous technology. This paper is the first step toward evaluating the research carried out by the research community all over world for tropical fruits. For the purpose of survey, we have concentrated on the tropical fruits of the state of Maharashtra, while keeping in focus of the review image processing algorithms.
The purpose of this study is to investigate the changes occured on phenolic compounds between two Malaysian varieties of pummelo fruit juice: Ledang (PO55) and Tambun (PO52) post-enzymatic clarification. The changes in polyphenols composition were monitored using High Performance Liquid Chromatography Diode Array Detection and Folin Ciocalteu's method. Clarification treatment of pummelo fruit juice with a commercial pectinase was optimized based on incubation temperature, time and enzyme concentration. Both varieties of pummelo fruit juice were treated with different optimized variables which produced the highest clarities with the least effect to the juice physical quality. Tambun variety was found to have significantly more total phenolic compounds (p <0.05) in comparison to Ledang variety, possibly due to the amount of naringin. Three types of hydroxycinnamic acids (chlorogenic, caffeic and coumaric acid) and three compounds of flavanones (naringin, hesperidin and narirutin) were found in both fruit juices, where naringin and chlorogenic acid were the major contributor to the total phenolic content. Naringin, which gave out bitter aftertaste to the juice, was found to decrease, 1.6 and 0.59 % reduction in Ledang and Tambun respectively, post-enzymatic treatment. The decrease in naringin, albeit nominal, could be a potential benefit to the juice production in reducing the bitterness of the juice. Post-enzymatic analysis furthermore resulted in no significance differences (p <0.05) on the total phenolic compounds of both varieties. This study in summary provides a compositional database for Malaysian pummelo fruit juice of various phenolic compounds, which can provide useful information for evaluating the authenticity and the health benefits from the juice.
The capacity of crustaceans to biosynthesise long-chain polyunsaturated fatty acids has yet to be fully defined, due to the lack of evidence on the functional activities of enzymes involved in desaturation or elongation of fatty acid substrates. We report here the cloning and in vitro functional analysis of an elongase from the orange mud crab, Scylla olivacea. Sequence and phylogenetic analysis placed the elovl close to the vertebrate Elovl1 and Elovl7 clade, which is distinct from the other remaining five Elovl families. The elongase was also clustered together with several elongases from crustaceans and insects. This elongase showed activities towards 16:1n-7, and at lower rate, linoleic acid (18:2n-6) and linolenic acid (18:3n-3). To our knowledge this is the first description of a functional enzyme involved in biosynthesis of long-chained polyunsaturated fatty acids in a crustacean species. Expression of the S. olivacea elovl7-like mRNA was prominent in stomach, intestine and gill tissues, due to the need to regulate the permeability of epithelial tissue through modification of fatty acid compositions. The implication of our findings, in terms of ability of Crustacea phylum to biosynthesise polyunsaturated fatty acids is discussed.
Sinensetin, a plant-derived polymethoxylated flavonoid found in Orthosiphon aristatus var. aristatus and several citrus fruits, has been found to possess strong anticancer activities and a variety of other pharmacological benefits and promising potency in intended activities with minimal toxicity. This review aims to compile an up-to-date reports of published scientific information on sinensetin pharmacological activities, mechanisms of action and toxicity. The present findings about the compound are critically analyzed and its prospect as a lead molecule for drug discovery is highlighted. The databases employed for data collection are mainly through Google Scholar, PubMed, Scopus and Science Direct. In-vitro and in-vivo studies showed that sinensetin possessed strong anticancer activities and a wide range of pharmacological activities such as anti-inflammatory, antioxidant, antimicrobial, anti-obesity, anti-dementia and vasorelaxant activities. The studies provided some insights on its several mechanisms of action in cancer and other disease states. However, more detail mechanistic studies are needed to understand its pharmacological effects. More in vivo studies in various animal models including toxicity, pharmacokinetic, pharmacodynamic and bioavailability studies are required to assess its efficacy and safety before submission to clinical studies. In this review, an insight on sinensetin pharmacological activities and mechanisms of action serves as a useful resource for a more thorough and comprehensive understanding of sinensetin as a potential lead candidate for drug discovery.
Based on an ethnobotanical study on use for plant species against mosquito bites in the Kota Tinggi District, Johor State, Malaysia, 3 plants selected for study, Citrus aurantifolia (leaves), Citrus grandis (fruit peel), and Alpinia galanga (rhizome), were extracted using hydrodistillation to produce essential oils. These essential oils were then formulated as a lotion using a microencapsulation process and then tested for their repellent effect against Aedes aegypti. N,N-diethyl-m-toluamide (deet) was also prepared in the same formulation and tested for repellency as controls. Four commercial plant-based repellent (KAPS(®), MozAway(®), BioZ Natural(®), and Mosiquard(®)) also were incorporated in the bioassay for comparison purposes. Bioassays revealed that at 20% concentration all repellent formulations demonstrated complete protection for 2 h and >90% for 4 h post-application. The A. galanga-based formulation provided the greatest level of protection (98.91%), which extended for 4 h post-application and was not significantly different from deet at similar concentration. When compared with commercial plant-based repellents (KAPS(®), MozAway(®), and BioZ Natural(®)), the 3 lotion formulations showed significantly better protection against Ae. aegypti bites, providing >90% protection for 4 h. In conclusion, our 3 plant-based lotion formulations provided acceptable levels of protection against host-seeking Ae. aegypti and should be developed.
This work studied the effectiveness of gaseous ozone disinfection on pummelo (Citrus Grandis L. Osbeck) fruit juice components. Unfiltered and filtered pummelo fruit juices were treated with gaseous ozone for up to 50 min with ozone concentration fixed at 600 mg/h. A microbiological and physicochemical properties analysis were conducted on the ozone-treated fruit juices samples. It was found that the survival rate of aerobic bacteria, yeast and mold in unfiltered pummelo fruit juice were higher compared to filtered juice, as the juice components acted as protective barriers to the microorganisms. The microorganisms' inactivation in pummelo fruit juices was also observed to have increased as the ozone treatment time increased. Significant effects on total colour difference, ascorbic acid content, and total phenolic content were also observed over increased ozone-treatment time. However, ozone was shown to be ineffective in activating PME activity in both types of juice. The experimental results of this study indicated that pummelo fruit juice components had significant effects on the effectiveness of gaseous ozone, however, the degree of the effects depends on the different fruit components (total soluble solids, total phenolic content). As a conclusion, filtered juice showed better quality characteristics in comparison to unfiltered juice post-ozone treatment.
Banana is the second largest cultivated fruit crop in Malaysia, and is cultivated for both the domestic market and also for export. Anthranose is a well-known postharvest disease of banana and with high potential for damaging market value, as infection commonly occurs during storage. Anthracnose symptoms were observed on several varieties of banana such as mas, berangan, awak, nangka, and rastali in the states of Perak and Penang between August and October 2011. Approximately 80% of the fruits became infected with initial symptoms characterized as brown to black spots that later became sunken lesions with orange or salmon-colored conidial masses. Infected tissues (5 × 5 mm) were surface sterilized by dipping in 1% sodium hypochlorite (NaOCl) for 3 to 5 min, rinsed with sterile distilled water, and plated onto potato dextrose agar (PDA). Direct isolation was done by transferring the conidia from conidial masses using an inoculation loop and plating onto PDA. For both methods, the PDA plates were incubated at 27 ± 1°C with cycles of 12 h light and 12 h darkness. Visible growth of mycelium was observed after 4 to 5 days of incubation. Twenty isolates with conidial masses were recovered after 7 days of incubation. The isolates produced grayish white to grayish green and grey to moss dark green colony on PDA, pale orange conidial masses, and fusiform to cylindrical and hyaline conidia with an average size of 15 to 19 × 5 to 6 μm. Appresoria were ovate to obovate, dark brown, and 9 to 15 × 7 to 12 μm and setae were present, slightly swollen at the base, with a tapered apex, and brown. The cultural and morphological characteristics of the isolates were similar to those described for C. gleosporioides (1,2,3). All the C. gloeosporioides isolates were deposited in culture collection at Plant Pathology Lab, University Sains Malaysia. For confirmation of the identity of the isolates, ITS regions were sequenced using ITS4 and ITS5 primers. The isolates were deposited in GenBank with accessions JX163228, JX163231, JX163201, JX163230, JX163215, JX163223, JX163219, JX163202, JX163225, JX163222, JX163206, JX163218, JX163208, JX163209, JX163210, JX431560, JX163212, JX163213, JX431540, and JX431562. The resulting sequences showed 99% to 100% similarity with multiple C. gloeosporioides isolates in GenBank. Pathogenicity tests were conducted using mas, berangan, awak, nangka, and rastali bananas. Fruit surfaces were sterilized with 70% ethanol and wounded using a sterile scalpel. Two inoculation techniques were performed separately: mycelia plug and conidial suspension. Mycelial disc (5 mm) and a drop of 20 μl spore suspension (106 conidia/ml) were prepared from 7-day-old culture and placed on the fruit surface. The inoculated fruits were incubated at 27 ± 1°C for 10 days at 96.1% humidity. After 3 to 4 days of inoculation, brown to black spotted lesions were observed and coalesced to become black sunken lesions. Similar anthracnose symptoms were observed on all banana varieties tested. C. gloeosporioides was reisolated from the anthracnose lesions of all the inoculated fruit in which the cultural and morphological characteristics were the same as the original isolates. To our knowledge, this is the first report of C. gloeosporioides causing anthracnose of Musa spp. in Malaysia. References: (1) P. F. Cannon et al. Mycotaxon 104:189, 2008. (2) J. E. M. Mordue. Glomerella cingulata. CMI Description of Pathogenic Fungi and Bacteria, No. 315. CAB International,1971. (3) H. Prihastuti et al. Fungal Diversity 39:89, 2009.
Serving raw oysters with lemon juice is a delicacy in many restaurants in
Malaysia. Oysters (Crassostrea virginica) live in the seacoast and they share the same
environment as Vibrio parahaemolyticus. Consumption of raw oysters contaminated with V.
parahaemolyticus can lead to severe gastroenteritis. A study was performed to determine
whether lemon (Citrus limon) juice is able to inhibit the growth of V. parahaemolyticus after
being inoculated in raw oysters. Methods: Frozen oysters bought from a local supplier
weighing 6 g each were minced and placed in two bottles using sterile technique.
Approximately 1 ml of 107 CFU of V. parahaemolyticus (ATCC strain 17802) was added and
mixed in both bottles. The mixture was treated with 1 ml of lemon juice in only one of the
bottles and the other bottle served as a control. At every 30 s intervals for 2 min, 1 g of the
sample was taken for enumeration of viable cells onto thiosulphate citrate bile salt sucrose
(TCBS). Results: After 30 s of treatment with the lemon juice, it was observed that the
number of colonies in the treated samples reduced from 7 Log to 3 Log. Subsequently, no
viable V. parahaemolyticus was seen. It was also observed that there were 3 Log reductions
of V. parahaemolyticus after 30 s in untreated samples, however the number of colonies
remained stable until the end of the experiment. Conclusion: This study therefore shows
that lemon juice has some antimicrobial effect on V. parahaemolyticus in raw oysters.
Citrus is one of the major commodities in many countries including Malaysia.
However, production of citrus including Citrus suhuiensis (C. suhuiensis) is declining due to
diseases and inability to withstand low temperatures. Plant cultures such as cell suspension have the
potential in propagating disease-free and healthy Citrus fruits with value-added characteristics.
However, studies related to C. suhuiensis is still scarce. Therefore, the growth kinetics of C.
suhuiensis cell suspension culture was studied. Friable callus of C. suhuiensis which was induced
from seeds was inoculated into MS medium with 30 g/L sucrose, 0.5 g/L malt extract and 2.0 mg/L
2, 4-D for the cell suspension initiation. Several batch experiments using a few types of sugars
(sucrose, glucose and fructose) were carried out. The cell dry weight (CDW) of C. suhuiensis was
recorded for 30 days of culture period and residual sugars in the medium were analyzed using
HPLC. Cells grown in 30 g/L sucrose achieved the highest CDW (9.559 g/L) with µmax equals to
0.00512/h, compared to glucose and fructose. In addition, sucrose is the preferred carbon source
with the highest uptake rate (0.213 g/L·h). Cells completely hydrolyzed sucrose into glucose and
fructose after 5 days of inoculation. All sugars were completely utilized by C. suhuiensis cells after
25 days. The kinetic growth parameters determined from batch experiments were then used for
model simulation and verification in MATHCAD 15. After adjustments and refinement to the
selected kinetic parameters, the model has fairly described and predicted the growth and sugars
profile of C. suhuiensis cells. The proposed model can be used to predict sucrose hydrolysis, glucose
and fructose formation from sucrose and their consumption by plant cells and also for larger scale
of growth.
Tomatoes have a short shelf life thus they pose a big challenge for growers to maintain the quality of tomatoes to increase customer acceptance. In this study, fungi associated with tomato disease symptoms were isolated and the potential of kaffir lime aqueous extract was evaluated in maintaining post-harvest quality of tomatoes. For this purpose, healthy tomatoes were dipped in 10% aqueous kaffir lime extract before evaluating the post-harvest parameters namely weight loss and firmness. A fungus namely Rhizophus stolonifer was isolated from the symptomatic tomatoes. Subsequently, it was confirmed to be pathogenic on healthy tomato fruits with 100% disease severity. Application of aqueous kaffir lime extract showed that tomato fruits dipped in 10% aqueous kaffir lime extract recorded higher weight loss and higher firmness as compared to untreated tomato fruits. The results showed that treatment with this concentration of plant extract did not help to reduce the weight loss, but it retained the firmness of the tomato fruits stored at room temperature at 27+2oC. Higher transpiration process would lead to shrinkage, weight loss, changes in texture and appearance of the fruits. Therefore, this study suggested an increased concentration of aqueous kaffir lime extract as a treatment agent in order to have a better effect in maintaining the quality of tomato fruits.
A rapid, sustainable, and ecologically sound approach is urgently needed for the production of semiconductor nanomaterials. CuSe nanoparticles (NPs) were synthesized via a microwave-assisted technique using CuCl2·2H2O and Na2SeO3 as the starting materials. The role of the irradiation time was considered as the primary concern to regulate the size and possibly the shape of the synthesized nanoparticles. A range of characterization techniques was used to elucidate the structural and optical properties of the fabricated nanoparticles, which included X-ray diffraction, energy-dispersive X-ray spectroscopy (EDX), atomic force microscopy, field emission scanning electron microscopy, Raman spectroscopy (Raman), UV-Visible diffuse reflectance spectroscopy (DRS), and photoluminescence spectroscopy (PL). The mean crystallite size of the CuSe hexagonal (Klockmannite) crystal structure increased from 21.35 to 99.85 nm with the increase in irradiation time. At the same time, the microstrain and dislocation density decreased from 7.90 × 10-4 to 1.560 × 10-4 and 4.68 × 10-2 to 1.00 × 10-2 nm-2, respectively. Three Raman vibrational bands attributed to CuSe NPs have been identified in the Raman spectrum. Irradiation time was also seen to play a critical role in the NP optical band gap during the synthesis. The decrease in the optical band gap from 1.85 to 1.60 eV is attributed to the increase in the crystallite size when the irradiation time was increased. At 400 nm excitation wavelength, a strong orange emission centered at 610 nm was observed from the PL measurement. The PL intensity is found to increase with an increase in irradiation time, which is attributed to the improvement in crystallinity at higher irradiation time. Therefore, the results obtained in this study could be of great benefit in the field of photonics, solar cells, and optoelectronic applications.