Calamondin Research Articles

Chemical composition and cytotoxicity of Philippine calamansi essential oil

The development of drug resistance is widespread in today's arsenal of chemotherapeutic agents and this has brought renewed interest in the use of natural products. Calamansi (Citrus microcarpa B.) is an essential oil-rich citrus from the Philippines popularly used in beverages and condiments. Calamansi wastes from processing plants are underutilized and may pose environmental concerns if not properly processed. This study aims to determine the volatile composition, d-limonene content, and cytotoxicity of calamansi essential oil. The calamansi essential oil was prepared by steam distillation and characterized using Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy and Gas Chromatography analysis. Cytotoxicity on human mammary tumor cell line MCF-7 and Chinese hamster ovary non-tumor cell line AA8 were assessed by MTT assay. Gas Chromatography-Mass Spectrometry qualitative analysis results revealed that d-limonene is the major constituent of calamansi essential oil comprising at least 92.67% of the total oil. Quantification of d-limonene in essential oil using a reference standard by Gas Chromatography-Flame Ionization Detector has shown 98.1% w/w. The IC50 of calamansi essential oil on MCF-7 and AA8 cells were identified to be 7.98 ± 1.77 and 16.15 ± 8.35 μg/mL respectively. Our findings suggest that calamansi essential oil has greater cytotoxic activity on MCF-7 than AA8 and this activity can be directly attributed to the high amount of d-limonene and perhaps the presence of other terpenes that may also have synergistic effects with d-limonene. Calamansi essential oil can be a good candidate for a natural low-cost chemopreventive and chemotherapeutic agent. These findings are of considerable economic interest to Philippine calamansi industry which produces large amount of calamansi pericarp waste.

CHEMICAL COMPOSITION OF VOLATILE COMPONENTS IN THE LEAVES OF CITRUS PLANTS CULTIVATED UNDER GREENHOUSE CONDITIONS

The article presents the results of research of the chemical composition of easily volatile components in the leaves of nine taxa representing species and varieties of the genus Citrus L. cultivated under the conditions of greenhouses of the Central Botanical Garden of the National Academy of Sciences of Belarus as: C. unshiu (Tanaka ex Swingle) Marcow., C. grandis Osbeck cv. Bogatyr, C. sinensis Osbeck cv. Washington Navel, C. medica L. cv. Sarcodactilis, C. medica cv. Pavlovskiy Shishkan, Lemon Skernevitsky (’Ponderosa lemon’) is a clone of the hybrid C. medica L. × C. limon (L.) Burm. f., Citrofortunella microcarpa, C. limon (L.) Osbeck cv. Pavlovskiy, C.meyeri (Ju. Tanaka). The volatile components were extracted using a Supelco™ solid-phase microextractor placed in the vapour-air space above air-dried, finely ground and heated to 40 °C leaf samples. The component composition of the extracts was analyzed by the GC/MS method using the Agilent Technologies 6850 Series II system (Network GC System/5975B (VL MSD). Total 36 components were identified in the leaves of citrus plants: monoterpenes (14), sesquiterpenes (11), and oxygen-containing compounds: terpene alcohols, aldehydes, ethers (11). The studies have shown that the cyclic hydrocarbons monoterpene (Z)-β-trans-Ocimene and 3 sesquiterpenes (β-caryophyllene, (3E, 6E)-α-farnesene, and α-caryophyllene) were detected in the volatile components in leaves in the whole citrus group. While 2 sesquiterpenes: (3E,6E)-α-farnesene and α-caryophyllene are dominant for the most taxa based on their proportions in the total volume of volatile compounds. Sesquiterpene beta-Elemene is present as a dominant component exclusively in species and varieties representing the so-called “sweet citrus” group as it follows from the results of the studies: C. unshiu, C. grandis cv. Bogatyr, C. sinensis× cv. Washington Navel, C. meyeri, which allows one to consider it as a significant feature in the taxonomy of the genus Citrus L.

Efek Penambahan Minuman Air Jeruk Sambal (Citrus Microcarpa) Terhadap Performa Broiler

This research aim to determine the effect of native orange (Citrus microcarpa) to drink water on body weight, feed consumtion and FCR (feed convertion rate). The variables in this study were body weight, feed consumption and feed conversion in broiler. The used materials were day old chick (DOC) strain CP707 as many as 80 birds, were placed in cages with size of (5,5 x 2,5 x 2 m) is partitioned into 20 units an each unit in the experiment with the contents of 4 chickens. Feed used is commercial feed. The method used completely randomized design (CRD), with 4 treatment and 5 replications. with level treatment P0 (commercial feed and 0% native orange for 1 L water), P1 (commercial feed and 0,4 native orange for 1 L water), P2 (commercial feed and 0,8% native oramge for 1 L water) and P3 (commercial feed and 1,2% native orange for 1 L water). Data were analyzed using analysis of variance at level 5% and followed by honesty significant different (HSD). The result showed treatment not significant with body weight, feed consumtion and FCR (feed convertion rate). Conclusion increment native orange to drink water not significantly on body weight, feed consumtion and FCR (feed convertion rate). Keyword: Citrus microcarpa, Broiler and Performance

Calamansi (× Citrofortunella microcarpa) for potential citrus fruit production for the island of Guam

Calamansi (× Citrofortunella microcarpa) is a very popular citrus for local cuisine in the tropical island of Guam. A study was conducted to determine the fruit yield of field-grown calamansi from 2004 to 2016 in a calcareous soil. Rooted stem cuttings of local calamansi were planted in 2002 with an intrarow spacing of 2.4 m and an interrow spacing of 6 m. There were four 60 m rows, each with 28 plants, totaling 112 trees. The yield increased steadily from 2004 (0.7 t ha-1) to 2009 (12.2 t ha-1), and then plateaued with the average yield of 11.8 t ha-1 from 2009 to 2016. The highest fruit yield of 14.6 t ha-1 was observed in 2014. When the monthly fruit yield was compared with the rainfall pattern from 2008 to 2016, floral initiation appeared respond to decreased rainfall during September to November. Fruit production peaked during the dry months of February to April. A preliminary biochemical analysis of calamansi juice was performed at three different fruit maturity stages: green, yellow, and orange fruits. The sugar content (°Brix), pH, vitamin C content, and Trolox equivalent antioxidant capacity (TEAC) were examined. Fruits of all stages had a pH of 2.4 and TEAC did not differ among the three stages of fruit maturity. However, sugar and vitamin C content increased from green to yellow to orange ripe fruits.

Citrus fruit extracts with carvacrol and thymol eliminated 7-log acid-adapted Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes: A potential of effective natural antibacterial agents

Despite the widespread belief that citrus fruit extracts (CFEs) are microbiologically safe due to their acidity, limited bactericidal effect results in low applicability as antibacterial agent and outbreaks occurred by acid-adapted pathogens. Here, we examined the antibacterial effects of CFEs [lime (Citrus medica), lemon (Citrus limon), calamansi (Citrus microcarpa)] combined with essential oil components (EOCs; carvacrol and thymol) against non-acid-adapted/acid-adapted Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes under 22 °C for 5 min. CFEs (<20%) alone or small amounts of EOCs (2.0 mM; 0.032%) alone could not inactivate the target bacteria effectively. However, combined treatments exhibited marked synergy: CFE + EOCs eliminated all the bacteria (>6.9 log CFU/ml). Among the CFEs tested, the highest synergism was shown by calamansi, an exotic citrus fruit previously unrecognized as an antibacterial agent. Although acid-adaptation improved bacterial survival, calamansi (<20%) + EOCs (<0.032%) completely inactivated even the most resistant pathogen (E. coli O157:H7). Validation test also showed that all tested commercial juice products also eliminated acid-adapted pathogens when used with EOCs. Physicochemical analysis of tested CFEs (pH measurement and HPLC analysis of components) revealed that low pH and flavanone (hesperidin) did not contribute to the synergistic bactericidal effects. Rather, the high citric acid content is likely to contribute to the strong synergistic effect with EOCs by damaging susceptible bacterial membranes. Sensory scores for CFEs were not altered by addition of EOCs at concentrations up to 1.5 mM. This study provides new insight into the utility of CFEs with EOCs to improve not only the microbiological safety of food products containing CFEs but also their applicability as natural antibacterial complex.

Physicochemical characterization and bioactivity evaluation of essential oils from Citrus microcarpa Bunge leaf and flower

Content of essential oils in flower and leaf of Citrus microcarpa was 1.1 and 0.8% (v/w), respectively. The flower oil was dominated by monoterpene hydrocarbons in which limonene (74.5%) was determined as a major component. The dominant constituents found in the calamondin leaf oil were sesquiterpene (82.0%) with elemol (37.5%) as a major component. The obtained thermal data showed that thermal stability of flower and leaf oils was up to 80 and 110 °C, respectively. A study of TG isothermal volatilization at 42.5 °C showed the mass loss of the essential oils as a function of exposition time. Antioxidant assays using both DPPH and ABTS radical scavenging methods exhibited antioxidant activity of flower and leaf essential oils was higher than that of vitamin C. The leaf essential oil exhibited inhibitory effects against six microbial strains while the flower oil inhibited only one fungus strain, A. niger.

In silico approaches illustrate the evolutionary pattern and protein-small molecule interactions of quinolone synthase from Aegle marmelos Correa

Quinolone synthase from Aegle marmelos (AmQNS) is a Rutacean-specific plant type III polyketide synthase that synthesizes quinolone, acridone, and benzalacetone with therapeutic potential. Simple architecture and broad substrate affinity of AmQNS make it as one of the target enzymes to produce novel structural scaffolds. Another unique feature of AmQNS despite its high similarity to acridone forming type III polyketide synthase from Citrus microcarpa is the variation in the product formation. Hence, to explore the characteristic features of AmQNS, an in-depth sequence and structure-based bioinformatics analyses were performed. Our studies indicated that AmQNS and its nearest homologs have evolved by a series of gene duplication events and strong purifying selection pressure constrains them in the evolutionary process. Additionally, some amino acid alterations were identified in the functionally important region(s), which can contribute to the functional divergence of the enzyme. Prediction of favorable amino acid substitutions will be advantageous in the metabolic engineering of AmQNS for the production of novel compounds. Furthermore, comparative modeling and docking studies were utilized to investigate the structural behavior and small molecule interaction pattern of AmQNS. The observations and results reported here are crucial for advancing our understanding of AmQNS’s phylogenetic position, selection pressure, evolvability, interaction pattern and thus providing the foundation for further studies on the structural and reaction mechanism.

A Candida parapsilosis inactivation-based UV-C process for calamansi (Citrus microcarpa) juice drink

Spoilage yeasts were isolated from ready-to-drink calamansi juice stored at room temperature. Biochemical and morphological characterizations revealed that both isolates were Candida parapsilosis. Known population of each of the two isolates was separately inoculated to freshly prepared juice drink and individually subjected to UV-C inactivation challenge. Both isolates (BC1 and SC1) exhibited a biphasic inactivation behavior, with an inactivation curve with upward concavity. The inactivation curves of both isolates had an initial inactivation lag time with minimal or no population change (7.78–14.64 s), followed by fast log-linear population decay (0.03–0.09 log CFU/s). Despite exhibiting the same inactivation behavior, the inactivation kinetic parameters of the two isolates were significantly different, with the SC1 isolate being more resistant. The inactivation kinetic parameter of the SC1 isolate was therefore used as basis for the establishment of UV-C process for the same calamansi juice drink with a lethal rate against the test organism equal to 99.999%. Application and evaluation of the process showed that the processed juice drink had sensory quality attributes not significantly different from non-processed samples. These results provide baseline information on the application of UV-C as a non-thermal processing technology for calamansi juice drink and other similar food matrices.

Toxicity of Citrus mitis, Citrus aurantifolia, and Citrus maxima leaf extract toward mortality of Aedes aegypti larvae (Diptera: Culicidae)

Dengue Fever is a significant health issue in Indonesia for it is always been found and unresolved since 1968. Dengue Fever is transmitted through mosquito (Aedes aegypti) bite. Resistance of mosquito larvae towards temephos as consequence of chemical larvicide consumption has been reported in several countries. One of safe and environmentally friendly efforts to control mosquito is by using herbal larvicide which produced from plants. This study examines methanol extract of Citrus mitis, Citrus aurantifolia, and Citrus maxima leaf toward mosquito larvae Ae. aegypti instar III for 24 hours. Data of larvae mortality is analyzed using probit analysis by SPSS software. The result shows that Citrus mitis has the highest toxicity with the lowest lethal concentrations (LC) that are LC50 = 1.547 ppm and LC90 = 3.328 ppm. It followed by Citrus aurantifolia and Citrus maxima respectively.Keywords: larvicide; Aedes aegypti; leaf extract; Citrus mitis; Citrus aurantifolia; Citrus maxima

Effect of extrusion on the carotenoid content, physical and sensory properties of snacks added with bagasse of naranjita fruit: optimization process

ABSTRACTExtruded third-generation snack foods (TGS) can be produced adding materials rich in bioactive compounds, such as the bagasse of naranjita fruit (Citrus mitis B.). The aim of this work was to study the effect of extrusion temperature (ET; 89.8–140.2°C), moisture content (MC; 21.10–32.89%) and dehydrated naranjita bagasse (DNB) content (1.12–11.88%) on TGS properties, such as, carotenoids content, physical and sensory characteristics. For data analysis, response surface methodology was used. The highest expansion index and the lowest penetration force were presented at high ET and low MC, whereas the highest carotenoids content and ΔE were presented at high DNB. Also, the highest sensory acceptability was presented combining high ET and MC, and low DNB. The optimal processing conditions were ET = 125°C, MC = 23% and DNB = 8.03%. TGS with acceptable physical and sensory properties, in addition to important carotenoid levels, were obtained.

Traditional Small-Size Citrus from Taiwan: Essential Oils, Bioactive Compounds and Antioxidant Capacity.

Background: The calamondin (Citrus microcarpa Bunge) and the kumquat (Fortunella crassifolia Swingle) are two small-size citrus fruits that have traditionally been consumed in Taiwan; however, there has been a lack of scientific research regarding the active compounds and functionalities of these fruits. Methods: Analysis of volatile composition of essential oil and phytosterol was carried out using Gas Chromatography–Mass Spectrometry (GC-MS). Flavonoid and limonoid were analyzed by High Performance Liquid Chromatography (HPLC). Moreover, antioxidant capacity from their essential oils and extracts were assessed in vitro. Results: The compositions of the essential oils of both fruits were identified, with the results showing that the calamondin and kumquat contain identified 43 and 44 volatile compounds, respectively. In addition, oxygenated compounds of volatiles accounted for 4.25% and 2.04%, respectively, consistent with the fact that oxygenated compounds are generally found in high content in citrus fruits. In terms of flavonoids, the calamondin exhibited higher content than the kumquat, with disomin-based flavonoids being predominant; on the other hand, phytosterol content of kumquat was higher than that of calamondin, with amyrin being the dominant phytosterol. Both of them contain high amounts of limonoids. The ethanol extracts and essential oils of small-sized citrus fruits have been shown to have antioxidant effects, with those effects being closely related to the flavonoid content of the fruit in question. Conclusions: The present study also reviewed antioxidant activity in terms of specific bioactive compounds in order to find the underlying biological activity of both fruits. The calamondin and kumquat have antioxidant effects, which are in turn very important for the prevention of chronic diseases.

FIRST REPORT OF CITRUS BENT LEAF VIROID IN MALAYSIA

Citrus are among eight major fruits crops grown in Malaysia, with a total production of 36,450 tons in 2013. Citrus bent leaf viroid (CBLVd, genus Apscaviroid, family Pospiviroidae), is widely distributed in citrus with no specific symptoms associated with its infection but responsible for leaf bending on Etrog citron. Leaf samples of citrus species such as calamondin [Citrofortunella microcarpa (Bunge) Wijnands], kaffir lime (Citrus hystrix DC.), key lime [C. aurantifolia (Cristm.) Swingle], mandarin orange (C. reticulata Blanco), pomelo (C. maxima Merr.), sweet orange [C. sinensis (L.) Osbeck] with stunting, leaf yellowing and epinasty were collected from different states in Malaysia. The rootstocks of these samples were not known. Total nucleic acids were extracted from leaves around the tree canopy and tested by RT-PCR with two sets of primers, CBLV-CM/CBLV-CP (Ashulin et al., 1991) and the newly designed YI4F/YI4R (5’-CGGAGACTTCTTGTGGTTCC-3’ and 5’-CTTGGAAGTCCGCTCGACTA-3’, respectively). Altogether 21 of 133 citrus samples were positive for CBLVd. The resulting amplicons of 328 bp and 234 bp in size were cloned. Sequence analysis revealed 95-99% identity with CBLVd isolate Jp (accession No. AB006734), confirming the presence of CBLVd (KU194472, KX823338-KX823343) in the tested samples. No particular symptoms were observed in the test samples correlated with the presence of CBLVd, thus the observed symptoms may not be induced by this viroid. To the best of our knowledge, this is the first report of CBLVd in Malaysia. Additional investigations on geographical distribution, epidemiology and economic impact are essential to formulate CBLVd management strategies in Malaysia.

Inhibitory Activity of Citrus Madurensis Ripe Fruits Extract on Antigen-induced Degranulation in RBL-2H3 Cells

The purpose of this study was to search edible ripe Citrus fruits which are applicable for functional food materials as juice, tea and/or jam with sweet taste and rich aroma. A fifty percent ethanolic extract (CMR-ext) obtained from the edible ripe fruit of Citrus madurensis exhibited an inhibitory activity of antigen-induced degranulation in anti-dinitrophenyl (DNP) IgE antibody sensitized rat basophilic leukemia (RBL) -2H3 cells. The inhibitory effect of the CMR-ext on degranulation in RBL-2H3 cells was attributable to 3’,5’-di-C-β-glucopyranosylphloretin (1) which is a constituent of C. madurensis. The effect of 1 on Akt and mitogen-activated protein kinases (MAPK) phosphorylation was examined in RBL-2H3 cells. Western blot analysis revealed that 1 (50 μM) inhibited the degranulation by suppression of Akt and p38 phosphorylation.

Induksi Kalus Jeruk Kasturi (Citrus microcarpa) Menggunakan Hormon 2,4-D dan BAP dengan Metode in vitro

Calamansi fruits ( Citrus microcarpa ) or musk lime is one horticulture crops has been known as beverage and food flavorings. This research aimed to determine the effect of 2,4-D and BAP on callus induction of explants calamansi fruits ( Citrus microcarpa ). Parameters observed is percentage of explants, time appeared callus, callus width, and texture of the callus. Research results and a growing percentage of the width callus explants were analyzed by ANOVA and a further test DMRT at 5% level. The next to appear callus timing parameters and texture of callus analyzed in description. The result shows that a combination of hormones D 4 B 1 and D 4 B 2 produces a callus emerged fastest of 3.3 days after culture. The highest percentage of callus formation that is 100% contained in the treatment of D 2 B 0 , D 2 B 0.5 -D 4 B 0 . The mean width of callus was highest in treatment D 4 B 2 with a width of 0.97 cm. Embryogenic callus resulting by treatment of D 2 B 1 , D 2 B 2 , and D 3 B 0 . However, the best a combination of hormones is treatment D 2 B 2 (2 mg/l, 2,4-D, dan 2 mg/l BAP) producing embryogenic callus edvanced to suspension cultures.

Antiangiogenic and antioxidant properties of Calamansi Citrus microcarpa peel ethanolic extract

&lt;p&gt;Angiogenesis or the development of blood vessels and oxidation or the radical transformation of cellular substances are two key processes that contribute to cancer progression. This study evaluated the antiangiogenic and antioxidant properties of different concentrations of calamansi (Citrusmicrocarpa)ethanolic peel extract. Preliminary quantification of active compound phenolic acid in 1 ml of 0.1% extract solution revealed 0.005% phenolic acid content. By chorioallantoic membrane (CAM) assay of 11-day duck embryo, 0.10 g/ ml to 0.30 g/ml extract revealed significantly lower numbers of blood vessels compared to the untreated control (p&amp;lt;0.05), in a concentration-dependent fashion, demonstrating antiangiogenic property of the extract. On the other hand, by 1, 1-Diphenyl-2-picrylhydrazyl (DPPH) assay, 0.10% to 0.50% extract concentrations were tested against DPPH radical using ascorbic acid as positive control. Spectrophotometric analysis revealed significantly stronger inhibition of DPPH radical by the extract than by ascorbic acid (p &amp;lt; .05), demonstrating more powerful antioxidant property of the extract than ascorbic acid. Hence, the study proved that C. microcarpa peel extract exhibits both antiangiogenic and antioxidant properties. Development of anti-cancer therapy envisaged, antiangiogenic and antioxidant bioassays of the extract using tumor-positive animal models are recommended.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Keywords:&lt;/strong&gt; Pharmacology, antiangiogenic, antioxidant, CAM Assay, DPPH Assay, Citrus microcarpa, Philippines&lt;/p&gt;

Optimization of an Air-Drying Process to Obtain a Dehydrated Naranjita (Citrus MitisB.) Pomace Product With High Bioactive Compounds and Antioxidant Capacity

The objective of this work was to optimize the effect of drying temperature (DT; 50–84C) and air velocity (AV; 0.48–1.32 m/s) on physicochemical and nutrimental properties of a dehydrated naranjita (Citrus mitis B.) pomace product. A hot-air dryer and the response surface methodology for data analysis were used. When DT was increased, the time to reach equilibrium moisture decreased. The lowest total color difference was presented at intermediate DT and AV, whereas the highest content of total phenolic compounds, antioxidant capacity, and retention of total carotenoids were presented combining high DT and low AV. The drying process increased total phenolic compounds and antioxidant capacity, and decreased retention of total carotenoids, compared with fresh material. The optimal area was in the range of 59.51–75.31C (DT) and 0.68–1.25 m/s (AV), obtaining a dehydrated naranjita pomace product with appropriated physicochemical and nutrimental properties, which was used as ingredient for making breakfast cereals, which presented good sensory acceptability. Practical Applications The dehydrated naranjita pomace product (DNP) obtained in this study provides an important solution to the problem of the environmental pollution derived from the by-products that are wasted during the citrus processing. The DNP might improve the nutritional properties in different foods when added as a supplementary ingredient because of its important levels of dietary fiber, carotenoids, phenolic compounds and antioxidant capacity. Additionally, DNP could enhance sensory attributes because it provides an attractive orange color and citrus flavor, making it appropriate for the production of foods such as breakfast cereals, enriched snacks, bakery products, jams and desserts.

Application of Chitosan and Chinese Lemon Extract (Citrus Mitis) Based Edible Coating on Tuna Fillet

Fish is a food that is very susceptible to degradation. One way to maintain the freshness of the fish is by using packaging edible coating with natural ingredients. This study used that chitosan and chienese lemon extract (Citrus mitis) as the natural agent in edible coating production. The purpose of this study was to examine the application of edible coating made from chitosan and citrus mitis on tuna fillets and to test the application of edible coating at each concentration, to get the best concentration based on pH and Total Bacterial Count (TBC). Tuna fillet with a size of 3 x 5 cm with a thickness of 1 cm was made edible coating by immersion system. Furthermore, edible coating made from chitosan in the concentrations of 1–4% was made by acetic acid solvent of 1% at a temperature of 50°C for 60 min, followed by the addition of 0.5% glycerol. On the other hand, edible coating made from citrus mitis in the concentration of 10-40% was made by jelly solution of 1% at 50°C for 60 min, followed by adding 0.5% of glycerol. Based on this study, it was understood that the best concentration for edible coating made from chitosan and citrus mitis was respectively 1% (pH 5.67; TBC 4.93) and 40% (pH 5.32; TBC 6.23). Furthermore it was known that the higher acid concentration, the better edible coating was obtained.

A research on evaluation of some fruit kernels and/or seeds as a raw material of vegetable oil industry

The crude oils obtained from the kernels of apple (Malus spp.), plum (Prunus domestica L.), apricot (Prunus armeniaca L.), sweet cherry (Prunus avium L.), mandarin (Citrus mitis), peach (Prunus persica L.), sour cherry (Prunus cerasus L.) and grape (Vitis vinifera L.) fruits were examined for some of their physicochemical properties and fatty acid compositions. The total oil content of the kernels ranged between 18.5-39.5%. While grape (20.2%) and apple (18.5%) seeds show the lowest oil content, the highest oil content was found in peach (39.5%) and apricot (38.8%) kernels. The saponification number and unsaponifiable matter contents of the samples varied between 170-195 and 0.93-1.59, respectively. The refractive index values of plum (1.478 nD 20 °C) and apricot (1.475 nD 20 °C) kernel oils were higher than the values of other kernel oils. The specific gravity, iodine number, peroxide value, free fatty acid and total crude fat contents of the kernels varied between 0.901 and 0.960, 95 and 135, 1.87 and 3...

Enhancing the antioxidant activity of immature calamondin by heat treatment

SummaryThe purpose of this study was to investigate the enhancing effect of heat treatment (110 and 130 °C for 0.5, 1.0, 1.5 and 2.0 h, and 150 °C for 1.5 h) on antioxidant activity and phenolic compounds of immature calamondin (Citrus mitis Blanco). The results indicated that heat treatment could enhance the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) scavenging potency, oxygen radical absorbance capacity (ORAC) and total phenolic content. However, the major flavonoid, 3′,5′‐di‐C‐β‐glucopyranosylphloretin (DGPP), decreased drastically after being heated at ≥130 °C over 1.5 h. The increasing ratio of absorbance at UV420 nm coincided with the change of the antioxidant activity. Therefore, it was concluded that the browning products resulted in the increase of the antioxidant activity of immature calamondin heated at ≥130 °C over 1.5 h, while the increase of antioxidant activity at 110 and 130 °C ≤ 1.0 h heating was due to increased phenolic content.

Citrus microcarpa Extract as Immunostimulator in Controlling Edwardsiellosis in African Catfish Culture

&#x0D; &#x0D; &#x0D; This study was described Citrus microcarpa extract as an antimicrobial agent in controlling edwardsiellosis in African catfish culture. Edwardsiellosis due to Edwardsiella tarda was recognized as a problem in African catfish culture and may lead to mass mortality of the cultured fish. Many antibiotics were no longer effective to control this bacterial disease. Therefore, this study was carried out to investigate the potential of C. microcarpa extract to overcome this bacterial disease problem. The experimental fish were fed with medicated feed at three different concentrations (1 g kg-1; CM-1, 2 g kg-1; CM-2 and 4 g kg-1 of fish) of C. microcarpa extract for one week before they were intraperitoneally exposed to E. tarda. Enzyme linked immunosorbent assay (ELISA) was carried out to determine the value of antibody response to E. tarda in fish from group of fish that received medicated fish and the percentage of total cumulative mortality of the experimental fish were observed at the end of the experiment. The results showed that the value of antibody response to E. tarda in fish from group of fish which received medicated feed (CM-1, 0.148 ± 0.017 OD; CM-2, 0.143 ± 0.006 OD; CM-4, 0.163 ± 0.015 OD) were found significantly higher (P &lt; 0.05) compared to fish did not received medicated fish (0.00 OD). Whereas, percentage cumulative mortality of fish from all groups of fish received medicated feed (CM-1, 20.0 ± 10.0 %; CM-2, 16.7 ± 5.8 %; CM-4, 16.7 ± 5.8 %) were found significantly lower (P &lt; 0.05) compared to group of fish did not received medicated feed (56.7 ± 5.8 %). The findings of the present study indicated the huge potential of C. microcarpa extract as natural antimicrobial agent for aquaculture use.&#x0D; &#x0D; &#x0D;