Dioscorea spp.

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Effect of Curing Treatments on Seven Key Farmers’ Yams (Dioscorea spp ) in Ghana

Effect of Curing Treatments on Seven Key Farmers’ Yams (Dioscorea spp ) in Ghana

Curing of freshly harvested yams (Dioscorea spp.) is a process for wounded yams during harvest to heal. In this work the effectiveness of straw, polypropylene and jute sack on curing of seven key farmers’ yam varieties over a duration of 7, 14 and 21 days was studied. Seven key farmers’ yam varieties identified as Pona, Lariboko, Dente, Mutwumudoo, Serwah belonging to D. rotundata, Matches and Akaba belonging to D. alata were studied under different curing treatments. The percentage weight loss of yam tubers varied among the treatments over curing period. Curing un- der jute sack showed all yam varieties had weight losses less than 2.0%, within 7 days of curing. Five different varieties had weight loss less than 2.0% except Dente under the straw treatment. Mutwumudoo variety showed the highest water loss (8.4%) for polypropylene sheet and 6.9% for Lariboko in the control treatment. During 7 days curing the control and polypropylene treatment did not support yam curing. After 14 days of curing of tubers, similar tends were observed as in 7 days curing. After 14 days of curing under jute sack, percentage weight loss of the tubers ranges from 2.0% - 3.7%. In the straw treatment, the percentage weight loss ranges between 1.0% - 4.7% in all other varieties except Dente (D. rotundata) (8.2%). Polypropylene sheet treatment showed the highest percentage weight loss in Mutwumudoo variety (18.4%). A similar trend was observed for the yam tubers cured for 21days as percentage weight loss of tubers under jute sacks was 2.5 – 9.8%. Curing temperature and humidity ranged between 27˚C - 40˚C and 87% - 100% rh for yam tubers under the three different treatments of polypropylene, jute and straw. However, the con- trol treatment recorded lower humidity of 60% - 80% rh. Curing material, duration, climatic con- ditions and yam varieties influenced curing and Serwah variety, which is a D. rotundata is the best bet yam variety to cure under jute sack for 7, 14 and 21 days of curing.

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Physicochemical Properties of Low-Amylose Yam (Dioscorea Spp.) Starches and its Impact on α- Amylase Degradation in Vitro

Physicochemical Properties of Low-Amylose Yam (Dioscorea Spp.) Starches and its Impact on α- Amylase Degradation in Vitro

Yam tubers (Dioscorea spp) are consumed as a source of digestible carbohydrate by millions of people in the tropical and subtropical regions and in some European Countries [1]. Yam tubers are classified as either edible or non-edible, where non-edible cultivars are used primarily for their medicinal properties. Research shows that wild/non-edible yams may be used in the treatment of hypercholesteremia, menopausal symptoms [2], lipid metabolism and cardiovascular disease [3]. According to Bahado-Singh et al. [4] some edible yams may be beneficial to persons living with diabetes as the glycemic index of the cooked tubers are usually low to medium.

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Distribution, Diversity and Potential Production of Yams (Dioscorea spp.) in Sheko District, Southwest Ethiopia

Distribution, Diversity and Potential Production of Yams (Dioscorea spp.) in Sheko District, Southwest Ethiopia

Yams are grown for their modified, thickened root or stem which generally develop underground and few are above ground (aerial tubers for example Dioscorea bulbifera). These organs are rich in carbohydrate and are commonly used as staple food, livestock feed, or as raw materials for the production of industrial products. Farmers were stored the yams for the task of staple food and planting materials for the next season. Although the shelf-life of yam varied accordingly, the products lost frequently observed [11]: (1) Physical losses of the dried commodity (tubers) as the extended it beyond the shelf-life of it; (2) There are financial losses when handling older fresh roots and tuber, as there is price discounting in anticipation of physical losses. Discounts can be as high percentage for the tuber crops. (3) Losses due to change in use. For example if harvest fresh roots and tuber crops could not be marketed within three days of harvest or few exceed they may be processed into dried products of lower value. (4) Lost potential because of failure to harvest at the optimum time. The harvesting time of each root and tuber crop was fixed as it matured. If it is flexible, there was a loss in potential earnings if the timing is not optimal. (5) The value of dried tuber was related to its quality, so poor qualities represent a loss of income.

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Relative efficiency of positive selection and tissue culture for generating pathogen free planting materials of yam (Dioscorea spp )

Relative efficiency of positive selection and tissue culture for generating pathogen free planting materials of yam (Dioscorea spp )

in yam fields in single and mixed infections (Op- pong et al. 2007; Eni et al. 2010; Asala et al. 2012; Odedara et al. 2012). Poty-, potex-, badna- and cucumo-viruses have been reported in Dioscorea spp., but the most significant loss is caused by Yam mosaic virus (YMV) (Malaurie et al. 1998). Diseases accumulate over generations of the use of unhealthy seed tubers with threat of the extinction of valuable germplasm. Therefore, there is scarcity of virus-free seed yam. Up to 63% of the cost of production is spent on the purchase of seed (Ironkwe et al. 2007). This makes it necessary to improve the existing informal seed production and development of a formal yam seed system where regulatory rules are functional (Balogun et al. 2014).

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Proximate and Mineral Composition Variability in Ethiopian Yam (Dioscorea spp)

Proximate and Mineral Composition Variability in Ethiopian Yam (Dioscorea spp)

growing and storage organ plus plays an important role in the energy transfer reaction, oxidation and reduction process. Stunted plant growth in young plants is one of its deficiency symptoms [20]. Calcium deficiency in yam (Dioscorea spp) mostly affects the growth of new tissue at the vine, root and tuber tips. The earliest clear symptom of calcium deficiency may be premature inactivity of the vine tips. Root growth is particularly affected by calcium deficiency. Root tips may die, resulting in a cluster of branching just behind the tip. The growing tip of the tuber is affected and tubers may be blunt ended and short [21]. The present study also revealed positive association between stem height to phosphorous content and calcium content to tuber yield which is in agreement to these particulars.

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Dioscorea spp. Exploration at Manokwari Regency, West Papua, Indonesia

Dioscorea spp. Exploration at Manokwari Regency, West Papua, Indonesia

Dioscorea pentaphylla L. (Tomboreso/Five Leaf Yam) is the species with the largest tuber originating from tropical Asia and Eastern Polynesia, which then spread to Southeast Asia, Kauai, Molokai, Hawaii, Tahiti, Savii, North America and Florida [31]. In Manokwari, it was found in the range of temperature at 26.6 - 32.5 0 C, humidity 60.3 - 85.7% and light intensity 2840 - 26200 lux. This species has compound leaves with 3 leaves (PC-31); 4 leaves (PC-35, PC-33): 5 leaves (PC-37, PC-17, PC-42, PC-05, PC-35, PC-33, PC-27, PC-09) and 7 leaves ( PC-14). This species was found to have flowers on PC-33, PC-37 and fruit on PC-37. Its aerial tuber colour were dark brown (PC-14) and light brown (PC- 33).

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Assessment of genetic diversity of Dioscorea praehensilis (Berth.) collected from Central Region, Ghana using simple sequence repeat (SSR) markers

Assessment of genetic diversity of Dioscorea praehensilis (Berth.) collected from Central Region, Ghana using simple sequence repeat (SSR) markers

producing nations after Nigeria [2]. The genus Dioscorea spp comprises of about 450 species [3]. Only 50-60 species are available for cultivation and wild-harvest [3]. Africa’s most cultivated species are D. alata L., D. bulbifera L., D. cayenesis Lam, D. esculenta (Lour.) Burk, D. rotundata Poir and D. trifida L. [4]. The major wild yam species in Africa are D. abyssinica, D. sagitifolia, D. preahensilis, D. liebrechstiana, D. mangenotiana and D. lecardi [5]. Bush yam (Dioscorea praehensilis) which is one of the wild yams serves as a source of food and contributes greatly to the welfare of people in West Africa [6]. This species has a wide geographical range in Africa and occurs throughout the Western, Central and Eastern parts of the continent [5]. (Dioscorea praehensilis) is an edible wild yam that is mostly found around cocoa plantations in Ghana, has been known to fill the hunger gaps (food and income security) among cocoa farmers in Ghana for ages but is currently known to be disappearing [7]. The genetic variability level in these species of yams has been underutilized and understudied. There is the need to explore molecular markers of genotype characterization to determine the genetic variability level in D. praehensilis.

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Genetic and enzymatic polymorphisms of Interspecific Dioscorea Praensilis Dioscorea rotundata hybrides from côte d’ivoire

Genetic and enzymatic polymorphisms of Interspecific Dioscorea Praensilis Dioscorea rotundata hybrides from côte d’ivoire

cassava. In terms of rentability for farmers, yam has a weak productivity with 6.95 tons/ha (FAOSTAT, 2013) while this one from potato is 30 tons/ha. In Côte d’Ivoire, yam (Dioscorea spp) occupies the first position food crops yield. Its annual yield is estimated at 5.8 millions de tons of fresh tuber in front of cassava whom annual yield reaches 2.4 million tons (FAOSTAT, 2013).Yam tubers are source of food for millions of people. They serve as basic food for 2/3 of Ivorian population. With 525 kcal/person/day, yam is ranked at the second place among the ten first products available for consuption after rice (552 kcal/person/day) and the first place as tuber cop followed by cassava (315 kcal/person/day)

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DISTRIBUTION OF ANTIBIOTIC RESISTANT BACTERIA FLORA IN READY TO-EAT FOOD SAMPLES SOLD IN CALABAR METROPOLIS

DISTRIBUTION OF ANTIBIOTIC RESISTANT BACTERIA FLORA IN READY TO-EAT FOOD SAMPLES SOLD IN CALABAR METROPOLIS

Antibiotics susceptibility profile of bacteria isolates from the ready-to-eat food samples showed that all the isolates had multiple resistance to the antibiotics they were tested against. This observation was in agreement with that of Gundogan et al., (2006) who reported to have isolated Klebsiella spp and Escherichia coli with multiple antibiotic resistance from meat, chicken and meat ball samples. Also other studies by Lateef et al., (2005); Majolagbe et al., 2011, have reported to isolate E. coli, Staphylococcus aureus, Salmonella spp and Streptococcus spp from water, food and clinical samples with multiple antibiotic resistance.

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Does the Domestication of Yam Wild Type Dioscorea praehensilis and Dioscorea abyssinica has a Genetic Basis?

Does the Domestication of Yam Wild Type Dioscorea praehensilis and Dioscorea abyssinica has a Genetic Basis?

This study showed that wild yam domestication is not widespread because very hard to be achieved by farmers and also considered as dishonorable practice across the bariba ethnic group, recognized as a bigger yam producers. Only few domestication practicing have good skills on this practice. Our results showed that their morphological criteria of choice of wild material to be domesticated have a genetic basis. Indeed, a clear separation of each of the two wild species Dioscorea abyssinica and Dioscorea praehensilis in domesticable and non-domesticable was detected. Thus, molecular data were in perfect accordance with the knowledge of farmers separating D. abyssinica and D. praehensilis into domesticable and non domesticable groups on the basis of morphological characters. Therefore, farmers’

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Microbial contamination after sanitation of food contact surfaces in dairy and meat processing plants

Microbial contamination after sanitation of food contact surfaces in dairy and meat processing plants

ferent sites (the cheese-maker-stirrer and the milk filler tube), and at different time points (five months apart), were found to be closely related as demonstrated by PFGE (94% genetic similar- ity). Both isolates were identically ERY-resistant (ermC gene; iMLS B -resistance) and OXA-resistant (mecA gene) but differed in tetracycline resistance (PEN, TET, COT, CLI versus PEN, COT, CLI). In one biofilm-negative S. epidermidis isolate from the inside surfaces, multi-resistance to PEN, COT, and ERY (iMLS B ; ermC gene) was also detected. The genetic relatedness was also recorded in two S. aureus isolates found on the inside surfaces of the pasteurisation station and the milk filler tube, respectively. These isolates were of the same PFGE type and showed 96% similarity with the PFGE profile of one isolate from pasteurised milk filled with the device. This demonstrates the persistence of particular subpopulations of Staphylococcus spp. and their potential to spread in the dairy plant environment as well as dairy farms.

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Multiplex Real Time PCR for Detection of Campylobacter, Salmonella, and Shigella

Multiplex Real Time PCR for Detection of Campylobacter, Salmonella, and Shigella

FIG 1 (A) Real-time PCR simultaneously detects three different genes. Data from individual tubes, each containing the ATCC strains S. enteritidis 13076,S. flexneri 12022, and C. jejuni subsp. jejuni 33560, are shown in a single graph so that the separation between individual amplicon melting curves is illustrated (from left to right, invA, ipaH, and 16S rRNA). The y axis (fluorescence) represents the negative derivative of fluorescence over temperature versus temperature. (B) Melting curves of DNA isolated from pure cultures of (top) Salmonella (n ⫽ 26), (center) Shigella (n ⫽ 49), and (bottom) Campylobacter (n ⫽ 41). Curves are superimposed to show the reproducibility within species. The y axis (fluorescence) represents the negative derivative of fluorescence over temperature versus temperature. In the top and bottom panels, the hor- izontal lines at the bottom represent negative controls. In the bottom panel, the lowest peak represents a positive strain. (C) Agarose gel (2%) of amplicons of representative strains from the multiplex real-time PCR. From left to right, 1, 100-bp molecular weight ladder; 2, C. coli; 3, C. jejuni; 4, S. enteritidis; 5, S. infantis; 6, Salmonella spp.; 7, S. boydii; 8, S. dysenteriae; 9, S. flexneri; 10, S. sonnei; 11, C. jejuni subsp. jejuni ATCC 33560; 12, S. enteritidis ATCC 13076; 13, S. flexneri ATCC 12022; 14, diffusely adherent E. coli; 15, enteroaggregative E. coli; 16, enteropathogenic E. coli; 17, enterotoxigenic E. coli; 18, enteroinva- sive E. coli; 19, Shiga-like toxin producer E. coli; 20, E. coli K-12; 21, Pseudomo- nas aeruginosa; 22, Klebsiella pneumoniae; 23, Proteus mirabilis.

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Canine tick borne diseases in pet dogs from Romania

Canine tick borne diseases in pet dogs from Romania

Background: Tick-borne diseases are of substantial concern worldwide for animals as well as humans. Dogs have been a human companion for millennia, and their significant impact on human life renders disease in dogs to be of great concern. Tick-borne diseases in dogs represent a substantial diagnostic challenge for veterinarians in that clinical signs are often diffuse and overlapping. In addition, co-infections with two or more pathogens enhance this problem further. Molecular methods are useful to disentangle co-infections and to accurately describe prevalence and geographical distribution of tick-borne diseases. At this point, this information is lacking in many areas worldwide. Romania is one such area, where prevalence and distribution of several important pathogens need to be further investigated. To address this, we screened blood samples from 96 sick dogs with molecular methods for eight different pathogens including Babesia spp., Theileria spp., Hepatozoon spp., Anaplasma spp., Ehrlichia spp., “ Candidatus Neoehrlichia mikurensis ” , Mycoplasma spp., and Borrelia spp.

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Article: Identification and antibiogram study of bacteria isolated from different street food

Article: Identification and antibiogram study of bacteria isolated from different street food

The present study was conducted for the isolation, identification and antibiotic sensitivity of the bacteria isolated from different street food. Presence of coliforms in the sample might be due to poor quality of water, unhygienic vendor places and poor personal hygiene of vendors. Most Street vendors were illiterate and they did not have a clear hygienic knowledge about the preparation, storage and serving of the food. All isolates found resistant to Cefixime, Cefalexin, Erythromycin, Fusaric acid, Cefuroxime and Aztreonam. The results of this study suggested that although RTE foods are cheap and economical but they are not healthy due to lack of hygienic measures, dirty utensils, and vendor‘s hygiene. These factors contributing many species of bacteria but major pathogen is E. coli, Salmonella spp. Shigella spp., Klebsiella spp. and Staphylococcus spp. Basic and main source of bacterial infection is poor hygienic measures and this problem may be solved by improving supervision in food handling procedure, extended consumer education on transmission of enteric food borne diseases and food safety risks. So that street vended RTE foods should be manufactured under Good Hygienic Practices and conservation practices should be developed in order to minimize the microbial contamination of food.

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Nutritional Quality of Weaning Foods Formulated from Yam (Dioscorea alata and Dioscorea cayenensis) Composite Flours

Nutritional Quality of Weaning Foods Formulated from Yam (Dioscorea alata and Dioscorea cayenensis) Composite Flours

Abstract: Some potential weaning diets formulated from yam species Dioscorea alata variety Bètè bètè and Dioscorea cayenensis variety Lokpa, soybean and cassava have previously been evaluated. In this study, four different diets (unfermented flour made of Dioscorea alata, fermented flour made of Dioscorea alata, unfermented flour made of Dioscorea cayenensis, fermented flour made of Dioscorea cayenensis) were prepared and fed to weaning rats for a period of 28 days. The study aimed to find out the in vivo impact of these yam composite flours. The performance characteristics of the developed products were investigated and compared with those of Cérélac (a commercial weaning food).The body weight change (BWC) of rats fed the different diets was highest in the rats fed Cérélac (3.39 g) followed by rats fed the fermented composite flours (FBBF and FLOF; 1.97 and 2.00 g, respectively) and casein-based diets (2.48 g) and least in rats fed the unfermented composite flour diets (FBBNF and FLONF; 1.60 and 1.51 g, respectively). A similar trend was observed in the total feed and protein intakes of the experimental animals. Moreover, the rat fed fermented composite flours showed high Protein Efficiency Ratio (2.25 – 2.37), Biological Value (78.94 – 79.46), True Digestibility (80.11 – 92.28) and Net Protein Utilization (60.91 – 76.34), comparable to those obtained with the casein-fed rats. The present study have shown that the values obtained with the test diet, especially for the fermented composite flours compared favourably with the reference diets (Cérélac and casein) in all the parameters investigated and should be considered a good weaning diet from a nutritional point of view.

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Prevalence of Marteilia spp. in Thirteen Shellfish Species Collected from China Coast

Prevalence of Marteilia spp. in Thirteen Shellfish Species Collected from China Coast

(Feist, et al., 2009; Berthe, et al., 2004). Stocking at low density has been shown to be effective on the control and prevention of Marteilia spp. Infection (Feist et al., 2009). Copepod Paracartia grani (Copepoda, Calanoida) could contribute to the transmission of Marteilia refringens (Arzul et al., 2013; Carrasco et al., 2008; Audema rd et al., 2002). Mecocyclops, Euchaeta concinna, Calanus sinicus (Copepoda, Calanoida) , Paracalanus parvus (Copepoda, Ca lanoida), Calocalanus pavo (Copepoda, Calanoida), Phyllodiaptomustunguidus (Copepoda, Ca lanoida), etc., have been reported in China. Ho wever, to our knowledge, no study has been reported on the Paracartia grani in China. The general husbandry practices are usually stocking at high density in China, but Marteilia spp. has the low prevalence in Ch inese coastal bays, wh ich may due to lack of intermediate host Paracartia grani (or Paracartia grani is not the dominant species) in these seven bay areas of Ch ina, so it needs to be further studied.

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Screening for antidiarrheal activity of Psidium Guajava : A possible alternative in the treatment against diarrhea causing enteric pathogens

Screening for antidiarrheal activity of Psidium Guajava : A possible alternative in the treatment against diarrhea causing enteric pathogens

Psidium guajava leaves, commonly known as guava was screened against some common enteric pathogens like Escherichia coli, Shigella spp, Salmonella spp, Aeromonas spp, Staphylococcus aureus and Candida spp. The alcoholic and aqueous extracts of Psidium guajava leaves were obtained using the Soxhlet apparatus. Antimicrobial activity of the extracts were tested on Mueller Hinton Agar by the punch well technique. Significant inhibitory effects were observed against the isolates that were tested. Significant activity of ethanolic extract was observed against Vibrio, Aeromonas, Salmonella and Shigella species. Aqueous extract showed significant activity against candida and Escherichia coli. The results of the present study supported the claims of folk medicine for the use of this plant for the treatment of diarrhea. These results were encouraging and can be extrapolated further to consider the use of Psidium guajava leaf extracts as an alternative treatment option for diarrhea caused by the enteric pathogens.

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BACTERIOLOGICAL EXAMINATION OF ABATTOIR WITH REFERENCE TO ESCHERICHIA COLI AND STAPHYLOCOCCUS SPECIES

BACTERIOLOGICAL EXAMINATION OF ABATTOIR WITH REFERENCE TO ESCHERICHIA COLI AND STAPHYLOCOCCUS SPECIES

Due to unhygienic nature of the abattoir, faecal contaminations are likely to occur with the meat. Gram negative and gram positive bacteria such as E.coli, Staphylococcus spp, Klebsiella spp, Streptococcus spp, Salmonella spp, Clostridium spp, Bacillus spp, and Pseudomonas spp were found in abattoir site and some of these are food borne pathogens such as botulism, dysentery, gastroenteritis and typhoid (Fraze and Westhoff, 2004).

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Anaplasma phagocytophilum, Bartonella spp , haemoplasma species and Hepatozoon spp  in ticks infesting cats: a large scale survey

Anaplasma phagocytophilum, Bartonella spp , haemoplasma species and Hepatozoon spp in ticks infesting cats: a large scale survey

In a study performed in southern Italy in which 73 ticks from 15 cats were analysed using qPCR, the preva- lence of Bartonella spp. in the ticks was 2.7% (qPCR for detection of Bartonella spp. targeting the internal tran- scribed spacer 1 (ITS1)), but no haemoplasma, Ehrli- chia/Anaplasma spp. or H. felis DNA was detected [12]. In another study performed in south-west Italy, 132 ticks collected from 308 cats were analysed using qPCR; the prevalence of B. clarridgeiae in the ticks was 1.5% (qPCR for detection of Bartonella spp. targeting ITS1 followed by DNA sequencing) and the prevalence of Ehrlichia canis was 0.75% (qPCR for detection of Ehrlichia/Ana- plasma spp. targeting 16S rRNA followed by DNA se- quencing), but no haemoplasma or H. felis DNA was detected [13]. In a study performed in Switzerland in which 71 ticks collected from 39 cats were screened for haemoplasma species using qPCR, the prevalence of “Ca. M. haemominutum” was 2.8% and no M. haemofe- lis and “Ca. M. turicensis” DNA was detected (qPCR for detection of haemoplasma species targeting 16S rDNA) [14]. Other recent studies in which ticks were collected from both cats and dogs and screened for pathogens by PCR revealed a prevalence of A. phagocytophilum of 24.2% in Belgium (2373 ticks from 506 cats and 647 dogs) and 14.4% in Poland (93 ticks from 171 cats); however neither study indicated the prevalence of patho- gens in only those ticks collected from cats [15, 16].

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ORAL CANDIDASIS IS PERIODONTAL DISEASE: A BRIEF REVIEW

ORAL CANDIDASIS IS PERIODONTAL DISEASE: A BRIEF REVIEW

immunocompromised patients, such as those with advanced HIV infection, to identify the different species of yeast present at periodontal disease sites. Among the 76 fungal organisms isolated, 10.5% were C. dubliniensis, which was present in 4.4% of patients studied; C. albicans was the most frequently isolated yeast species. The Candida spp. are ubiquitous fungal organisms that often colonize the oral mucosa of normal individuals, without causing disease. These opportunistic microorganisms might influence the inflammatory process, as they possess several virulence factors by which they invade tissues and evade host defense mechanisms, thereby facilitating proliferation and release of exoenzymes that promote tissue degradation. Moreover, in immunosuppressed patients, the higher prevalence of Candida spp. (mainly C. albicans) in the oral cavity, and specifically the subgingival biofilm of periodontal pockets, could indicate their coparticipation in the progression of periodontal disease in these patients.

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