Acceso económico al insecto comestible Sphenarium Purpurascensen la Sierra Sur de Oaxaca, México / Economic access to the edible insect Sphenarium Purpurascensin the Sierra Sur of Oaxaca, México

FUNDAMENTOS: La ingesta del insecto Sphenarium Purpurascens Charpentier (SPC) prevalece en Oaxaca, pero crece su acceso como mercancía. El objetivo del estudio fue evaluar el acceso económico a SPC en un contexto de urbanización. MÉTODOS: Estudio transversal observacional. Se determinó la ración neta estándar (RNE) de SPC ingerida por día, precio y aporte nutricio mediante encuesta probabilística y análisis proximal. Para evaluar acceso económico, se comparó ante un mismo equivalente monetario el rendimiento en proteínas y energía de SPC con otros alimentos ofertados localmente, cuyos precios y aporte nutricio se obtuvieron por encuesta y tablas nutrimentales. También se determinó costo de oportunidad de SPC respecto a tales alimentos. RESULTADOS: La RNE de SPC es 39,2 g, cuesta en promedio 12,5 pesos mexicanos (MXN) equivalentes a 58,2 minutos de trabajo estándar; contiene 16,2 g de proteínas, 1,5 g de lípidos y 109 kilocalorías. La carne bovina presentó rendimiento nutricional similar a SPC. Los demás alimentos tuvieron rendimientos nutricionales y costos de oportunidad en proteínas, superiores; salvo filete de pescado y camarón. CONCLUSIONES: En la localidad estudiada, el acceso económico a SPC es restringido. Su proceso artesanal implica más trabajo y precio, comparado con alimentos de producción industrial

BACKGROUND: The intake of Sphenarium Purpurascens Charpentier (SPC) prevails in Oaxaca, although its access as merchandise grows. The aim was to evaluate the economic access to SPC in an urbanization context. METHODS: Cross-sectional and observational design. The standard net portion (SNP) of SPC ingested by day, its price and nutritional content was determined by probabilistic survey and proximal analysis. To assess the economic access, per monetary unit, yields of protein an energy from SPC and other locally offered foods were compared. Prices and nutrition facts of these foods were obtained by survey and nutrition tables Also was determined the opportunity costs of buying SPC respect those mentioned foods. RESULTS: The SPC is 39.2 g, costs an average of 12.5 MXN, equivalent to 58.2 minutes of standard work, and contains 16.2 g of protein, 1.5 g of lipids and 109 kilocalories. The beef of cattle has nutritional yields similar to SPC. The other foods have higher nutritional yields and buy SPC implies opportunity costs in proteins, except respect fish fillet and shrimp. CONCLUSIONS: SPC has less economic access in the studied locality. Its collection and preparation implies more work and greater price, than industrial production foods

Purification and identification of angiotensin I-converting enzyme-inhibitory peptides from apalbumin 2 during simulated gastrointestinal digestion.

BACKGROUND: Bee larvae are considered to be an important reservoir for proteins. However, little attention has been paid to the release of potential bioactive peptides from bee larva proteins. In this study the major protein in bee larvae was hydrolyzed in vitro by gastrointestinal enzymes. The peptide profile of the hydrolysis was characterized by gel filtration chromatography and tricine-SDS-PAGE. Furthermore, the bioactive peptide was isolated and identified by Q-TOF-MS/MS. RESULTS: The major bee larva protein was identified as apalbumin 2 and was more digestible into peptides with molecular weights lower than 3 kDa. The hydrolysate obtained after 3 h of digestion exhibited angiotensin I-converting enzyme (ACE)-inhibitory activity and was purified sequentially by gel filtration and RP-HPLC. The molecular weights of peptide fractions with ACE-inhibitory activity were distributed between 0.5 and 1.5 kDa. A novel peptide with highest ACE-inhibitory activity (IC50 54.9 µmol L(-1) ) was purified by further RP-HPLC. The amino acid sequence of this peptide was identified as LLKPY (632.40 Da). CONCLUSION: ACE-inhibitory peptides could be formed from bee larvae through gastrointestinal digestion. The most active peptide (LLKPY) is potentially useful as a therapeutic agent in treating hypertension.

Identification of ISSR markers associated with productivity traits in silkworm, Bombyx moni L.

Bombyx mori L., commonly recognised around the world as the mulberry silkworm, is characterized by a wide variability in yield and developmental traits, which have been proven through conventional genetic analysis to be of polygenic nature. A large number of morpho-biochemical traits and RFLP and RAPD markers are mapped on different linkage groups, but to this point very little attention has been given to unravelling the genetics of yield traits. To address this issue, polymorphic profiles of 147 markers generated with 12 ISSR primers on the genomic DNA of 20 silkworm stocks of diverse yield status were subjected to multiple regression and discriminant function analyses (DFA). This led to the identification of eight markers generated by six primers, which demonstrated high beta-coefficient indices of -0.451 to -0.940. Furthermore, a significant difference between the yield traits for stocks with and without the specific marker could also be established. The inheritance pattern of one marker, L13800bp, identified at the first step of selection of markers through stepwise regression analyses for five yield parameters is discussed in the context of applying multiple regression analysis for establishing association, if not linkage, between a group of DNA markers and a particular yield trait of polygenic nature and using such markers in molecular marker-assisted breeding programs.