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Volume 3 Number 1 2009 
CONTENTS AND ABSTRACTS
Ebenezer O. Farombi, Sunny O. Abarikwu, Isaac A. Adedara, Martins Ekor (Nigeria) Aflatoxins: Origin, Detection, Effect on Human Health and Safety, and Preventive Intervention Strategies (Focus on Developing Countries) (pp 1-22)
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Invited Review: Aflatoxins (AFs) are secondary metabolites of fungal origin produced by Aspergillus flavus. They contaminate agricultural commodities at pre- or post-harvest. Contamination of grains, peanuts and other dietary staples with AFs is a worldwide problem that affects both food safety and agricultural economies. Most countries have adopted regulations that limit the quantity of AFs in food and feed to ≤20 µg kg-1. Environmental conditions, especially high humidity and temperature, favour fungal proliferation resulting in contamination of food and feed. The socio-economic status of the majority of inhabitants of sub-Saharan Africa predisposes them to consumption of mycotoxin-contaminated products either directly or at various points in the food chain. AF contamination has been linked to liver cancer, immuno-suppression and impaired growth. Synergistic interactions between AF exposure and malaria, kwashiorkor and HIV/AIDS have been suggested. Methods to reduce AF contamination involving good agricultural practices such as early harvesting, proper drying, sanitation, proper storage and insect management, among others have been adopted. Other possible interventions include biological and chemical control, decontamination, breeding for resistance as well as surveillance and awareness creation. However, complete elimination of AF contamination might not be possible. Therefore efficient, practical and cost-effective approaches are needed in developing countries where the burden of liver cancer is highest. Chemoprevention strategies which alter AF disposition are a rational and pragmatic strategy to reduce the incidence of liver cancer in regions of the world with high dietary AF exposure. Modulation of AF disposition can be achieved through induction of conjugating and cytoprotective enzymes. Classes of chemopreventive agents such as oltipraz, epigalocatechin gallate, sulphoraphane, natural chlorophyll and kolaviron which induce cytoprotective enzymes have been identified. This new paradigm therefore raises the intriguing possibility of a novel therapeutic approach for hepatocellular carcinoma.
Guadalupe Virginia Nevárez-Moorillón (Mexico) Plant Spices as Sources of Natural Antimicrobials for Food (pp 23-32)
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Invited Review: Observation of consumer expectations regarding food quality provides the basic for any successful food production and marketing. This is also true for fresh fruits and vegetables which are increasingly valued as an important part of the diet. Traditional quality evaluation of fruits and vegetables is associated, primarily, with appearance attributes, such as size, shape, surface color and defects; tactile characteristics, such as firmness or hardness; and internal quality attributes, such as sugar and/or oil content, vitamins and internal defects and disorders. However, sensory attributes play an important role in a consumer’s decision to purchase fresh or fresh-cut fruit or vegetables. Preharvest practices such as cultivation, growing system, soil type, and fertigation, as well as harvest practices, such as choice of the stage of maturity and postharvest treatments, such as controlled or modified atmosphere packaging, coating, and physical or physicochemical treatments may affect the sensory and flavour attributes of fresh and fresh-cut product. The goal of this mini review is to summarize the information that has been published during the last 4 years on preharvest practices and postharvest treatments that affect the sensory characteristics of fruits and vegetables, marketed as fresh, or fresh-cut products.
Angela R. Piergiovanni, Rosanna Simeone, Antonella Pasqualone (Italy) Oriental Wheat an Underutilised Tetraploid Wheat Species. A Case Study: Nutritional and Technological Traits of Kamut (pp 33-38)
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Invited Mini-Review: Interest in the so-called ancient wheats (einkorn, emmer, spelt and Oriental wheat) has increased dramatically over the last decades. Of particular interest, in relation to human consumption, are the nutritional traits as well as the pasta- and bread-making performances. This is attributable to the strict relationships between these features and the economic value of food derivatives entirely or partially prepared using ancient wheat species. Studies on agronomic, biochemical and technological traits of emmer and spelt have been the object of some reviews, while little attention has been devoted to Oriental wheat (T. turgidum L. subsp. turanicum (Jakubz.) A. Löve & D. Löve). This review describes the current state of knowledge regarding genetic, compositional and technological traits of Oriental wheat, a neglected and underutilised tetraploid wheat species. Comparison with ancient and modern wheat cultivars is also discussed. Literature dealing with the accession QK-77, registered as Kamut®, the only variety belonging to this species, is analysed in depth. The results of field trials carried out in Southern Italy, a geographical area traditionally devoted to durum wheat cultivation, are discussed. Moreover, the state of the art about the incorporation or the preparation of popular foods with Kamut® is presented.
Robert S. Glew (USA), Boakye Amoako-Atta, Gloria Ankar-Brewoo (Ghana), Jack Presley (USA), Lu-Te Chuang (Taiwan), Mark Millson, Barrett R. Smith, Robert H. Glew (USA) Non-cultivated Plant Foods in West Africa: Nutritional Analysis of the Leaves of Three Indigenous Leafy Vegetables in Ghana (pp 39-42)
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Original Research Paper: Although non-cultivated indigenous leafy vegetables (ILVs) are widely consumed in Ghana and other parts of sub-Saharan Africa, particularly during periods of food scarcity, much remains to be learned about their content of essential nutrients. We collected the leaves of Cleome gynandra, Fleurya aestuans and Solanum nigrum growing near Kumasi and compared them in terms of their content of essential amino acids, fatty acids, and minerals and trace elements. All three plant foods contained (on a dry-weight basis) 21.6-26% protein whose essential amino acid pattern, except for the methionine/cysteine pair, compared favorably with a World Health Organization standard protein. Although fatty acids accounted for only 0.5-1.1% of the dry weight of the ILVs, the proportion of the essential omega-3 fatty acid α-linolenic acid was high (24.3-58.2%) in all three plants, and the omega-6/omega-3 ratio was a healthful 0.1 and 0.4, respectively for C. gynandra and S. nigrum, respectively. The leaves of the three ILVs contained nutritionally significant amounts of calcium, copper, iron, magnesium, manganese, molybdenum and zinc, but were devoid of detectable selenium. These results indicate that C. gynandra, F. aestuans and S. nigrum, which are widely regarded by the inhabitants of sub-Saharan Africa as ‘famine foods’, actually represent excellent potential sources of many different nutrients that are essential in humans.
Hock Eng Khoo, Amin Ismail (Malaysia) Stability of Carotenoids from Hexane Fractions of 12 Malaysian Underutilised Tropical Fruits during Low Temperature Storage (pp 43-46)
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Original Research Paper: A study on the stability of carotenoids in fruit extract is necessary due to rapid degradation of carotenoid compounds in the extract. Twelve selected underutilised tropical fruits were studied for their total carotene content (TCC) from hexane fractions under storage for 5 h at 0°C and 12 days at −20°C. Kinetic study revealed that the degradation rate of TCC was highly depended on the storage time. Storage for 12 days at −20°C had TCC degraded for more than 30% in hexane fractions of Bacang 1 (Mangifera foetida), Bacang 3 (M. foetida), Kuini (M. odorata) and Tampoi Putih (Baccaurea macrocarpa). Less than 5% of TCC was lost in hexane fractions of Cerapu 1 (Garcinia prainiana) and Cerapu 2 (G. prainiana). Most of the fruit’s hexane fractions demonstrated a moderate loss of TCC if stored at −20°C for about 2 weeks. A major loss of TCC was found in low antioxidant fruits. However, storage for 5 h at 0°C had TCC degraded for less than 15% in hexane fractions of Cerapu 2, Durian Nyekak 2 (Durio kutejensis) and Jentik-jentik (Baccaurea polyneura). In this study, a rapid degradation of carotenoids occurred if the fruit’s hexane fractions were stored at 0°C than at −20°C. Various factors may contribute to the degradation of carotenoid compounds in the fruits’ hexane fractions.
Nagarajan Anusuya, Sathyanarayanan Anusuya, Rajesh Manian, Perumal Siddhuraju, Sellamuthu Manian (India) Antioxidant and Free Radical Scavenging Activity of Certain Dietary and Medicinal Plant Extracts (pp 47-52)
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Original Research Paper: The antioxidant and free radical scavenging activity of the ethanol extracts of Melia dubia Hiern., Albizia lebbeck (L.) Benth., Brassica oleracea L. var. botrytis (broccoli) and Glycyrrhiza glabra L. were evaluated. The total phenolic content of the extracts was found to be higher in A. lebbeck (33.6%) and lower in broccoli (16.9%). The antioxidant activity of the extract was evaluated through different chemical assays and in vitro methods such as reducing power, DPPH·, ABTS·+ and ·OH radical scavenging activities, peroxidation inhibition in linoleic acid emulsion system and antihemolytic activity. The increasing concentrations of the extract exhibited nonlinear increases in the reducing power. Extract of A. lebbeck was found to have more hydrogen donating ability. Similar line of dose dependant activity has been observed in DPPH· and ·OH radical scavenging systems. Further, A. lebbeck extracts exhibited strong antioxidant activity equivalent to trolox (6423.04 µmol g-1) in ABTS radical cation scavenging system. All the extracts exhibited notable activity against linoleic acid emulsion system (35.5 to 40.2%) and antihemolytic activity (29.8 to 46.6%).
Fatma B. A. Mohy El-Din (USA), Zahra S. Ahmed, Ahmed R. Abdel Latief, Ahmed T. El-Akel, Salah H. Abou-Raya (Egypt) Chemical, Physical, Nutritional and Sensory Properties of High Fiber Healthy Corn Snacks (pp 53-57)
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Original Research Paper: High fiber low calorie healthy snacks were prepared using yellow corn grits incorporated with different fiber sources (soybean, carrot and pea hulls). The fibers sources were added to the yellow corn grits at 10-40% fibers to 90-60% yellow corn grits. The effects of added fibers on chemical (moisture, protein, fat, ash, crude fiber, total dietary fiber and carbohydrate), physical (expansion index, bulk density, water absorption, water solubility indexes, color attributes and breaking strength), nutritional (protein digestibility, carbohydrate digestibility and calorific value) and sensory (appearance, aroma, color, taste and texture) characteristics of extruded products were evaluated. Adding the soybean fiber, to the yellow corn grits, enhanced the sensory characteristics of the final extruded products displayed a great ability to produce an excellent extrudates compared with other fiber sources.
Ka-Soon Lee, Gwan-Hou Kim, Hyun-Ho Kim, Mi-Ran Song, Mee-Ree Kim (Korea) Changes in Concentrations of Ginsenosides and Free Amino Acids in Ginsengand GinsengSolution during the Jung Kwa Process (pp 58-64)
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Original Research Paper: This study was carried out to investigate the quality characteristics of Jung Kwa ginseng (JKG) and Jung Kwa ginseng solution (JKGS) prepared according to the boiling frequency of the Jung Kwa Process. JKG was made as follows: 8 kg of washed ginseng was boiled for 5 min with 16 L water from which 8 L boiling water was removed. 10 kg sucrose was added to the remaining boiled ginseng soaking in hot water. JKG was boiled for 60 min in sugar syrup and soaked for 24 hrs repeating the boiling process 5 times. After the final process the crude saponin content of Jung Kwa (JKG 6) increased 4-fold more, while the ginsenoside Rf and Rd contents increased 77- and 16-fold more than raw ginseng, respectively.The content of crude saponin in the second last JKG solution (JKGS 5) was 61.88 mg/g. Others ginsenosides in JKG decreased. As increasing the number of times boiled, crude protein and total free amino acid contents decreased 84.9 and 94.7% of raw ginseng in JKG but increased 98.2 and 78.9% in JKGS, respectively. Especially, the arginine content of JKG 6 decreased 49.18-fold more than raw ginseng while g-aminobutyric acid and two unknown compounds, not present in fresh, untreated ginseng, were formed as intermediate products during Jung Kwa processing. The g-aminobutyric acid content was 34.13 mg/100 g in JKG 6. In addition, unknown compound 1 was formed more than unknown compound 2 in JKG while unknown compound 2 was formed more than unknown compound 1 in JKGS.
Ibironke A. Ajayi (Nigeria) Proximate and Mineral Element Composition of Seven Selected Unexploited Oilseeds from Nigeria (pp 65-67)
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Research Note: Seven unexploited oilseeds were analyzed for their proximate and mineral element composition. Adansonia digitata Linn., Calophyllum inophyllum Linn., Monodora myristica Gaertn. Dunat, Pentaclethra macrophylla Benth., Terminalia catappa Linn. and Telfairia occidentalis Hook f. were classified as high-fat seeds, only D. edulis G. Don H. J. Lam was in the low fat class, their oil content ranging between 21.79 g/100 g dry matter (dm) in M. myristica to 55.05 g/100 g dm in T. catappa.All the seeds except for those of D. edulis had low moisture content that varied from 5.02 g/100 g dm in A. digitata to 7.50 in T. occidentalis, which shows that they have a long shelf life. Five of the seeds had high protein content, ranging from 13.00 to 32.10 g/100 g dm; these values compare favourablywith those of high-protein animal products like beef, pork and oyster. Carbohydrates, calculated by [100 g/100 g-(protein + ash + crude fat + moisture content)], varied significantly among the seeds. Analysis of macro- and micronutrients in the seeds showed potassium to be the most prevalent in all seeds with T. catappa having the highest value of 935.50 mg/kg dm.
Ali Sarkhosh, Zabihollah Zamani, Reza Fatahi, Mohammad Sayyari (Iran) Antioxidant Activity, Total Phenols, Anthocyanin, Ascorbic Acid Content and Woody Portion Index (wpi) in Iranian Soft-Seed Pomegranate Fruits (pp 68-72)
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Original Research Paper: Twenty one pomegranate accessions collected as soft-seed genotype from different parts of Iran and cultivated in Yazd pomegranate collection (center of Iran) were assayed for some of their nutritional traits, including antioxidant activity, phenols, anthocyanins and ascorbic acid content, and for woody portion index (wpi). Antioxidant activity ranged from 64.54 to 75.12% of 100% and ascorbic acid was variable between 16.50 to 22.66 mg/100 g fresh weight (fw) among accessions. Anthocyanin index (absorption of 25% diluted juice at 510 nm varied between 0.83 to 1.94 while the phenol content ranged from 12.60 to 18.97 mg/100 g dry weight (dw) in the aril and from 50.73 to 103.83 mg/100 g dw in the peel. The wpi of accessions varied from 5.37 to 14.13%, lower values of this parameter implying a softer seed and easily available nutritionally valuable seed contents such as fatty acids for the consumer. This study demonstrates the beneficial nutritional properties of pomegranate as an extremely rich source of antioxidants as well as the presence of extremely soft seeded genotypes between Iranian pomegranate germplasm. Also highly soft-seeded genotypes are a valuable source for genetic improvement of commercial pomegranate cultivars.
Kedar Kumar Rout, Satyaranjan Mishra, Sagar Kumar Mishra, Sabuj Sahoo (India) Determination of Bioactive Markers in Curcuma longa Rhizome (pp 73-76)
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Techniques Paper: A simple, precise and rapid HPTLC method has been developed and validated for quantitative determination of biologically active curcuminoids in four Curcuma longa samples collected from Kandhamal, Sambalpur, Bhubaneswar and local market of Orissa (India). The HPTLC method was optimized with the mobile phase consisting of chloroform: methanol, 9.6: 0.4 (v/v). The compounds were quantified at their maximum absorbance, at 430 nm. Limit of detection was found to be 15 ng for each curcuminoids and limit of quantification was found to be 50, 40, 50 ng for curcumin (1), demethoxycurcumin (2), and bisdemethoxycurcumin (3), respectively. The response was a linear function in the ranges 50-300, 40-200, and 50-250 ng with correlation coefficients of 0.9999, 0.9991, and 0.9986, respectively for 1, 2 and 3. Instrumental precision was found to be 0.46, 0.79, and 0.92% and repeatability of the method was 1.75, 1.80, and 2.25% for 1, 2 and 3 respectively. The mean recovery values were found to be 99.71% for 1, 98.74% for 2, and 99.23% for 3. Among the samples investigated the highest content of bioactive markers were accumulated in the Kandhamal sample.
Christian Agbo Ugwu, Ignatius Obi Ugwudike, Pauline Umeh Chikerenma (Nigeria) Genetic Variability in Protein and Amino Acid Composition in Leaves of some Gongronema latifolia Benth. Clones (pp 77-81)
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Original Research Paper: Analysis of leaves of Gongronema latifolia Benth. identified clone EBS 015 with 58.38% protein and nine essential amino acids. The clone was significantly different from other clones with respect to its protein content. The dominant amino acids identified in the clones used for study were glutamic acid (13.48 g/100 g protein), leucine (9.66 g/100 g protein) and aspartic acid (9.25 g/100 g protein); those in moderate amounts were arginine, lysine, alanine, valine, isoleucine, phenylalanine and glycine while those in low concentrations were histidine, methionine and cysteine. Even though significant differences existed in protein and amino acid concentrations in the clones, all of them, irrespective of their local area of collection had comparable levels in the quality of protein and amino acids. The availability of methionine and cysteine, which are pre-cursors of taurine in crop species, supports the wide use of the plant in the treatment of diverse ailments. A positive and significant correlation (r = 0.922: n =21) between lysine and serine and between essential and non-essential amino acids suggest complimentary relationship in the synthesis and availability of the amino acids in the species. Furthermore, the phenotypic and genotypic variances estimated indicate that there was a minor environmental influence on the expression of the clones suggesting higher genetic influence on the results obtained. The amino acid levels in the crop species have potential value in maintaining good health and for use in the manufacture of varying food supplements that will compare favorably with supplements from soybeans.
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