Predicting black soldier fly larvae biomass and methionine accumulation using a kinetic model for batch cultivation and improving system performance using semi-batch cultivation

Global demand for poultry and associated feed are projected to double over the next 30 years. Insect meal is a sustainable alternative to traditional feeds when produced on low-value high-volume agricultural byproducts. Black soldier fly (BSF) larvae (Hermetia illucens L.) are high in protein and contain methionine, an essential amino acid that is critical to poultry health. BSF larvae can be grown on many organic residues, however, larvae growth and quality vary based on feedstock and cultivation processes. Experiments were completed to monitor temporal changes in BSF larvae growth and composition using almond hulls as a growth substrate under batch and semi-batch processes and with varying substrate carbon to nitrogen ratio (C/N). A logistic kinetic growth model was developed to predict larval biomass and methionine accumulations during batch production. Estimated ranges of model parameters for larvae maximum specific growth rate and carrying capacity were 0.017–0.021 h−1 and 9.7–10.7 g larvae kg−1 hulls dry weight, respectively. Methionine content in larvae increased from 11.1 to 17.1 g kg−1 dry weight over a 30-day batch incubation period. Larvae-specific growth and yield increased by 168% and 268%, respectively, when cultivated in a semi-batch compared to a batch process. Increasing C/N ratio from 26 to 40 increased density of methionine content in larvae per unit feedstock by 25%. The findings demonstrate a logistic model can predict larvae biomass accumulation, harvest time can achieve specific methionine contents, and a semi-batch process is more favorable for larvae biomass accumulation compared to a batch process.

Quantitative Analysis of Histidine Amino Acid as a Predictor of Ergothioneine in the Drying and Frying Process of White Oyster Mushrooms (Pleurotus ostreatus)

ABSTRACTBackgrounds: White oyster mushroom (Pleurotus ostreatus) is widely cultivated by Indonesian people due to its delicious and nutritious taste. Pleurotus ostreatus contains 18 amino acids that make up the body and antioxidants, including phenolic compounds and ergothioneine. Ergothioneine as a strong antioxidant is an amino acid derived from histidine which has sulfur groups such as cysteine and methionine. The increase in histidine indicates the activity of ergothioneine.Objectives: This study aims to determine the amino acid content of histidine as a predictor of ergothioneine amino acid in the drying and frying process of white oyster mushrooms.Methods: The extraction method used in this study was maceration with 90% ethanol for drying samples and 70% ethanol for frying samples analyzed using High Performance Liquid Chromatography (HPLC).Results: The results showed that the histidine content increased with the longer drying time, and decreased with the longer frying time. Drying with a variation of 2 days, 3 days, and 5 days were 674788,802 mg/L; 615302.747 mg/L; and 1946113,494 g / L respectively. Frying with a variation of 2 minutes, 3 minutes, and 5 minutes were 500435,148 mg / L; 232428,391 mg/L; and 0.000 mg / L. On the other hand, the methionine content decreased with the longer drying time, and increased with the longer frying time. Drying with a variation of 2 days, 3 days, and 5 days in a row were 6673,283mg/L; 6671,920 mg/L; and 1876,358 mg / L. Frying with a variation of 2 minutes, 3 minutes, and 5 minutes were 2296,698 mg / L; 1243,911 mg/L; and 34764.534 mg/L.Conclusions: the study concludes that the content of histidine as the highest ergothioneine predictor is at drying for 5 days and frying for 2 days.

Plasma methionine metabolic profile is associated with longevity in mammals

Methionine metabolism arises as a key target to elucidate the molecular adaptations underlying animal longevity due to the negative association between longevity and methionine content. The present study follows a comparative approach to analyse plasma methionine metabolic profile using a LC-MS/MS platform from 11 mammalian species with a longevity ranging from 3.5 to 120 years. Our findings demonstrate the existence of a species-specific plasma profile for methionine metabolism associated with longevity characterised by: i) reduced methionine, cystathionine and choline; ii) increased non-polar amino acids; iii) reduced succinate and malate; and iv) increased carnitine. Our results support the existence of plasma longevity features that might respond to an optimised energetic metabolism and intracellular structures found in long-lived species.

The Resistance Responses of Potato Plants to Potato Virus Y Are Associated with an Increased Cellular Methionine Content and an Altered SAM:SAH Methylation Index

Plant-virus interactions are frequently influenced by elevated temperature, which often increases susceptibility to a virus, a scenario described for potato cultivar Chicago infected with potato virus Y (PVY). In contrast, other potato cultivars such as Gala may have similar resistances to PVY at both normal (22 °C) and high (28 °C) temperatures. To elucidate the mechanisms of temperature-independent antivirus resistance in potato, we analysed responses of Gala plants to PVY at different temperatures using proteomic, transcriptional and metabolic approaches. Here we show that in Gala, PVY infection generally upregulates the accumulation of major enzymes associated with the methionine cycle (MTC) independently of temperature, but that temperature (22° C or 28° C) may finely regulate what classes accumulate. The different sets of MTC-related enzymes that are up-regulated at 22 °C or 28 °C likely account for the significantly increased accumulation of S-adenosyl methionine (SAM), a key component of MTC which acts as a universal methyl donor in methylation reactions. In contrast to this, we found that in cultivar Chicago, SAM levels were significantly reduced which correlated with the enhanced susceptibility to PVY at high temperature. Collectively, these data suggest that MTC and its major transmethylation function determines resistance or susceptibility to PVY.

Formulation of baby biscuits with substitution of wood grasshopper flour (Melanoplus cinereus) as an alternative complementary food for children

The provision of complementary food is one effort to overcome nutrition problems in vulnerable groups such as children aged 12-24 months. Giving inadequate complementary food can cause malnutrition. The prevalence of malnutrition in Yogyakarta, Indonesia in 2017 was 8.26%. While in this region, there is a kind of insect, wood grasshopper, that commonly consumed as local food as a source of protein. In this study, wood grasshopper flour was used to substitute wheat flour to develop baby biscuits and analyze the amino acid, energy, nutrient content; protein quality; and organoleptic properties. An experimental study of a complete randomized one factor by substitution of wood grasshopper flour with variations in substitution of 0%, 5%, 7%, and 10%. Wood grasshopper is obtained directly from GunungKidul Regency, Yogyakarta. Substitution of wood grasshopper flour could enhance energy, protein, dietary fiber, zinc, and amino acid content level of lysine, leucine, phenylalanine, arginine. Whereas, decrease carbohydrate and methionine content. The most suitable energy, nutrient content, quality protein, and the preferred organoleptic of baby biscuits and fullfil the Indonesian regulation of complementary food is the formulation with the substitution of wood grasshopper flour as much as 5%. The suggested serving size of baby biscuits with the substitution of wood grasshopper flour is 6 pieces (60 g). Consumption of one serving size of baby biscuits with the substitution of wood grasshopper flour contributes to the adequacy of protein per day as much as 24-38% RDA of children aged 12-24 months from each formulation

Revisiting the attempts to fortify methionine content in plant seeds

The sulfur-containing amino acid methionine belongs to the group of essential amino acids, meaning that humans and animals must consume it in their diets. However, plant seeds have low levels of methionine, limiting their nutritional potential. For this reason, efforts have been made over the years to increase methionine levels in seeds. Here, we summarize these efforts and focus particularly on those utilizing diverse genetic and molecular tools. Four main approaches are described: (i) expression of methionine-rich storage proteins in a seed-specific manner to incorporate more soluble methionine into the protein fraction; (ii) reduction of methionine-poor storage proteins inside the seeds to reinforce the accumulation of methionine-rich proteins; (iii) silencing methionine catabolic enzymes; and (iv) up-regulation of key biosynthetic enzymes participating in methionine synthesis. We focus on the biosynthetic genes that operate de novo in seeds and that belong to the sulfur assimilation and aspartate family pathways, as well as genes from the methionine-specific pathway. We also include those enzymes that operate in non-seed tissues that contribute to the accumulation of methionine in seeds, such as S-methylmethionine enzymes. Finally, we discuss the biotechnological potential of these manipulations to increase methionine content in plant seeds and their effect on seed germination.

Effect of Fermentation on Enhancing the Nutraceutical Properties of Arthrospira platensis (Spirulina)

Arthrospira platensis (spirulina), a filamentous fresh-water planktonic cyanobacterium, possesses diverse biological activities and a unique nutritional profile, due to its high content of valuable nutrients. This study aimed to further improve the bioactive profile of spirulina, by fermenting it with the lactic acid bacterium Lactobacillus plantarum. In vitro comparison of the total phenolic content (TPC), C-phycocyanin, free methionine, DPPH radical scavenging capacity, ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC) and protein fragmentation via SDS-PAGE in untreated versus 12 to 72 h fermented spirulina is reported here. After 36 h fermentation, TPC was enhanced by 112%, FRAP by 85% and ORAC by 36%. After 24 h, the DPPH radical scavenging capacity increased 60%, while the free methionine content increased by 94%, after 72 h. Past 36 h of fermentation, the total antioxidant capacity (TAC) diminished, possibly due to deterioration of the heat-sensitive antioxidants. However, protein fragmentation and free methionine content increased, linearly, with the fermentation time. Cyanobacterial peptides and other bioactive compounds trapped within the spirulina cell wall are released during fermentation and have a significant potential as a functional ingredient in nutraceuticals and pharmaceuticals, in addition to their nutritive value.

Performance of agronomical and seed biochemical traits of soybean genotypes in relation to their tolerance and preference by Nezara viridula

Kuswantoro H, Ginting E, Utomo JS, Yusnawan E. 2019. Performance of agronomical and seed biochemical traits of soybean genotypes in relation to their tolerance to and preference by Nezara viridula. Biodiversitas 20: 356-363. Qualitative and quantitative variations of biochemical compounds in plant organs is one of the causes leading to infestation by a certain pest which prefers to feed on particular genotypes than other genotypes. Objectives of this study is to find out the relationship of selected agronomical features and seed biochemical contents of soybean genotypes with their tolerance to Nezara viridula and also the preference of N. viridula to these genotypes. A total of 50 soybean germplasm were grown at Muneng research station during the dry season of 2016. The variability of the tested germplasm was reflected in the diversity of agronomic characters and seed biochemical contents. There was a significant positive correlation among the studied seed biochemical parameters, namely protein, methionine and cysteine contents. The protein and cysteine contents did not relate to N. viridula preference, but it was related to soybean tolerance against N. viridula. It was indicated by the insignificant positive correlation of protein and cysteine contents with the number of unfilled pods and the negative correlation of protein and cysteine contents with the ratio of number of unfilled pods to the total number of pods. Methionine content increased N. viridula preference, but it had no effect on soybean tolerance. Five genotypes, namely MLGG 0164, MLGG 0195, MLGG 0103, MLGG 0896 and MLGG 0196 were selected based on high seed biochemical contents which can be used as gene sources in soybean breeding programs. Among these five genotypes, MLGG 0195 had high protein, methionine and cysteine contents, but it was not tolerant to N. viridula. Hence, this genotype should be cultivated by controlling N. viridula optimally. MLGG 0196 had the highest methionine content, relatively high cysteine content, and N. viridula tolerance. This genotype can be used to improve seed biochemical content and plant tolerance against N. viridula.