Optimizing coffee cultivation and its impact on economic growth and export earnings of the producing countries: The case of Saudi Arabia

Coffee is one of the historical socioeconomic crops. It has received an increasing attention at the global level, due to its positive interlinkage with the economic growth and on the gross domestic product for most of the producing countries, particularly, developing and least developed countries. Saudi Arabia is one of the coffee producing countries that has a relative comparative advantage of coffee cultivation. Yet, coffee cultivation has not received as much attention in Saudi Arabia as that of producing countries around the world. This study aims to assess the current state of coffee cultivation in Saudi Arabia and to investigate the potential to optimize coffee cultivation in Saudi Arabia that maximizes the net national economic return and export earnings, given limitation of cultivated areas, local market activities, and international trade activities. The study statistically analyzed primary data collected from around (65) coffee farms and traders in the study regions at the south and southwest Saudi Arabia, and optimized coffee cultivation in Saudi Arabia using LINGO optimization software. Empirical results of the study revealed the great potential of Saudi Arabia to expand coffee cultivation at south and southwest regions to meet the escalating local demand and to increase its share at the world market up to 2%. Optimization of coffee cultivation in Saudi Arabia showed a high potential to meet the local demand for coffee by producing 80.07 thousand tons grown over 2861.78 hectares and to generate a net return equivalent to $395.72 million a year, which is equivalent to $138.28 thousand per hectare and $4.94 thousand per ton of coffee. Optimizing coffee cultivation will play a substantial role to increase market share of Saudi Arabia to about 1–2% of the world market by increasing its export volume, respectively, to about 69.66 and 112.56 thousand tons, the national net economic return by about $395.86 and $395.95 million a year, and the export earnings of coffee by about $219.43–354.57 million a year, which in turns, will serve the national strategic trend to diversify the economic base and lower the dependency of incomes generated from oil exportation.     

Insulin release: Reconciliation of the receptor and metabolic hypotheses

Summary Nutrients which stimulate insulin secretion are currently thought to initiate the series of cellular events eventually leading to insulin release either by interacting with a stereospecific receptor system (the regulatory site hypothesis) or by acting as a fuel (the substrate site hypothesis) in the pancreaticB-cell. The latter hypothesis is supported by a number of observations indicating that the capacity of nutrients to stimulate insulin release is indeed highly dependent on their capacity to increase catabolic fluxes in isolated pancreatic islets. However, these observations do not rule out the existence of nutrient receptors in islet cells. For instance, a nonmetabolized analog of L-leucine stimulates insulin release by causing allosteric activation of glutamate dehydrogenase, which should be considered, therefore, as a receptor for certain amino acids. Likewise, the increase in glycolytic flux, which is associated with the process of glucose-stimulated insulin release, is attributable not solely to a mass action phenomenon but also to the activation of phosphofructokinase by fructose 2.6-bisphosphate. The biosynthesis of this activator may involve a glucose receptor system. The fact that certain nutrient secretagogues (e.g D-glucose and L-leucine) act in the B-cell both as substrates and enzyme activators permits reconciliation of the substrate site and regulatory site hypotheses for insulin release.     

Interleukin 6 and/or Interleukin 17A Modulate the OPG/RANKL System of MC3T3-E1 Murine Osteoblast Cell Line

Cytokines such as interleukin-6 (IL-6) and IL-17 which act as key regulators of the immune response have been identified to have a potential role in the bone remodeling mechanism. Receptor activator of NF-κB ligand (RANKL) has been shown to regulate osteoclast differentiation and function while the osteoprotegerin (OPG) blocks the binding of RANKL and inhibits the differentiation of osteoclasts, thus favoring osteogenesis. Alkaline phosphatase (ALP) on the other hand works as early mineralization indicator in bone regulation. The current study aims to determine the potential role of IL-6 and IL-17A in regulating the OPG/RANKL system of the murine osteoblast cell line (MC3T3-E1). Gene expression analysis showed significant up-regulation of OPG and ALP by all the treated groups (rIL-6, rIL-17A and rIL-6 + rIL-17A). In contrast, treatment of cells with rIL-6 and/or rIL-17A showed down-regulation of RANKL expression. Interestingly, the osteoblast cells treated with combinations of rIL-6 + rIL17A showed marked increased in OPG/RANKL ratio. Similar pattern of protein expression was observed in the osteoblasts treated with rIL-6 and/or rIL-17A as detected by western blotting and ELISA. These findings suggest a new mechanism of regulation by these cytokines on the expression of OPG and RANKL, which could promote osteogenesis and diminish osteoclastogenesis.     

Identification of tissue-specific microRNAs from mouse

MicroRNAs (miRNAs) are a new class of noncoding RNAs, which are encoded as short inverted repeats in the genomes of invertebrates and vertebrates. It is believed that miRNAs are modulators of target mRNA translation and stability, although most target mRNAs remain to be identified. Here we describe the identification of 34 novel miRNAs by tissue-specific cloning of approximately 21-nucleotide RNAs from mouse. Almost all identified miRNAs are conserved in the human genome and are also frequently found in nonmammalian vertebrate genomes, such as pufferfish. In heart, liver, or brain, it is found that a single, tissue-specifically expressed miRNA dominates the population of expressed miRNAs and suggests a role for these miRNAs in tissue specification or cell lineage decisions. Finally, a miRNA was identified that appears to be the fruitfly and mammalian ortholog of C. elegans lin-4 stRNA.     

Confirmation of Acrocephalus scirpaceus avicenniae (Aves: Acrocephalidae) from mangroves on the Red Sea coast near Jazan,southwest Saudi Arabia

Members of the Eurasian (or Common) Reed Warbler complex, Acrocephalus scirpaceus, are widespread across much of Europe, Africa, the Middle East and Central Asia. With its relatively complex taxonomy, the identity of several local (and sometimes remote) populations remains somewhat unresolved. In Saudi Arabia, populations of reed warblers were first identified in mangroves at Yanbu’ on the Red Sea coast in 1984, with several subsequent records up to 900 km further south toward the Yemen border. We took morphological data from 51 individuals and genetic material from three individuals captured near Jazan in southwest Saudi Arabia. Both genetic and morphometric data confirmed that these birds belong to the taxon A. scirpaceus avicenniae, sometimes referred to as the Mangrove or Red Sea Reed Warbler.     

Oscillations in glycolysis: multifactorial quantitative analysis in muscle extract

A multifactorial quantitative analysis of oscillations in glycolysis was conducted in the postmicrosomal supernatant of rat muscle homogenates incubated in the presence of yeast hexokinase. Oscillations in adenine nucleotides, D-fructose 1,6-bisphosphate, triose phosphates, L-glycerol 3-phosphate, ³HOH generation from D-[5-³H]glucose, NADH and L-lactate production were documented. The occurrence of such oscillations were found to depend mainly on the balance between the consumption of ATP associated with the phosphorylation of D-glucose, as catalyzed by both yeast and muscle hexokinase, and the net production of ATP resulting from the further catabolism of D-fructose 6-phosphate, as initiated by activation of phosphofructokinase. The oscillatory pattern was suppressed in the presence of D-fructose 2,6-bisphosphate. It is proposed that the quantitative information gathered in this study may set the scene for further studies in extracts of cells other than myocytes, e. g. hepatocytes and pancreatic islet cells, in which no oscillation of glycolysis was so far observed.     

Synthesis and carbonic anhydrase inhibitory properties of novel bromophenols including natural products

(2-Bromo-3,4-dimethoxyphenyl) (3,4-dimethoxyphenyl)methanone (10) and its derivatives with Br, one dibromide and isomeric three tribromides, were synthesized. Demethylation of these compounds afforded a series of new bromophenols. Inhibition of human cytosolic carbonic anhydrase II (hCA II) isozyme by these new bromophenols and naturally occurring 3,4,6-tribromo-5-(2,5-dibromo-3,4-dihydroxybenzyl)benzene-1,2-diol (3), and 5,5'-methylenebis(3,4,6-tribromo-benzene-1,2-diol) (4) was investigated. The synthesized compounds showed carbonic anhydrase inhibitory capacities with IC(50) values in the range of 0.7-372 μM against hCA II. Some bromophenols investigated here showed effective hCA II inhibitory activity and might be used as leads for generating novel carbonic anhydrase inhibitors which are valuable drug candidates for the treatment of glaucoma, epilepsy, gastric and duodenal ulcers, neurological disorders, or osteoporosis.     

Estimation of 16S rRNA gene copy number in several probiotic Lactobacillus strains isolated from the gastrointestinal tract of chicken

The copy numbers of 16S rRNA genes in 12 probiotic Lactobacillus strains of poultry origin were analyzed. Genomic DNA of the strains was digested with restriction endonucleases that do not cut within the 16S rRNA gene of the strains. This was followed by Southern hybridization with a biotinylated probe complementary to the 16S rRNA gene. The copy number of the 16S rRNA gene within a Lactobacillus species was found to be conserved. From the hybridization results, Lactobacillus salivarius I 24 was estimated to have seven copies of the 16S rRNA gene, Lactobacillus panis C 17 to have five copies and Lactobacillus gallinarum strains I 16 and I 26 four copies. The 16S rRNA gene copy numbers of L. gallinarum and L. panis reported in the present study are the first record. Lactobacillus brevis strains I 12, I 23, I 25, I 211, I 218 and Lactobacillus reuteri strains C 1, C 10, C 16 were estimated to have at least four copies of the 16S rRNA gene. In addition, distinct rRNA restriction patterns which could discriminate the strains of L. reuteri and L. gallinarum were also detected. Information on 16S rRNA gene copy number is important for physiological, evolutionary and population studies of the bacteria.