Study on fermentation preparation, physicochemical properties and biological activity of carboxymethylpachymaran with different degrees of substitution

BACKGROUND

Carboxymethylpachymaran (CMP) is created by carboxymethylating pachyman (PM), which increases its water solubility and enhances a number of biological activities. Traditional polysaccharides modified by carboxymethylation employ strong chemical techniques. Carboxymethylcellulose (CMC) has been used previously for liquid fermentation to carboxymethyl modify bacterial polysaccharides. This theory can be applied to fungal polysaccharides because Poria cocos has the ability to naturally utilize cellulose.

RESULTS

CMC with different degrees of substitution (DS) (0.7, 0.9 and 1.2) were added to P. cocos fermentation medium, and CMPs with different DS (0.38, 0.56 and 0.78, respectively) were prepared by liquid fermentation. The physical and chemical properties and biological activities of the CMPs were determined. Their structures were confirmed by Fourier transform infrared (FTIR) spectroscopy and monosaccharide composition. With the increase of DS, the viscosity and viscosity-average molecular weight of CMPs decreased, whereas polysaccharide content and water solubility increased, although the triple helix structure was not affected. The results of bioactivity assay showed that the higher the DS of CMPs, the higher the 2,2-diphenyl-1-picrylhydrazyl radical scavenging ability, and the stronger the bacterial inhibition ability.

CONCLUSION

The present study has developed a method for producing CMPs by P. cocos liquid fermentation. The results of the study confirm that enhancing the DS of CMP could effectively enhance its potential biological activity. The findings provide safe and reliable raw materials for creating CMP-related foods and encourage CMP application in the functional food industry. © 2024 Society of Chemical Industry.

Immobilization of Coprinus comatus with magnetic alginate hydrogel microsphere for improving the antioxidant activity of fermentation products

Coprinus comatus is an edible mushroom and its fermented product possesses antioxidant activity. In this study, to further enhance the antioxidant activity and improve the reusability of the strain, calcium alginate hydrogel was used as the carrier for embedding and immobilizing Coprinus comatus. The effects of CaCl2 concentration, sodium alginate concentration, microsphere diameter, and the amount of magnetic particle on the antioxidant activity of fermented products were investigated. The results showed that the magnetic immobilized microsphere prepared by 2.50% CaCl2, 2.00% sodium alginate and 0.50% Fe3O4 had the best fermentation antioxidant activity (EC50 was 0.43 ± 0.01 mg/mL) when the diameter was 5 mm, which increased by 24.56% compared to the initial activity. Besides, the microsphere showed strong reusability, the antioxidant activity was still better than the free strain after being used five times. This study not only enhanced the antioxidant activity of Coprinus comatus fermented product through immobilization, but also provided an effective method for microbial fermentation.

Synergetic effects and inhibition mechanisms of the polysaccharide-selenium nanoparticle complex in human hepatocarcinoma cell proliferation

BACKGROUND

Active components from natural fungal products have shown promising potential as anti-tumor therapeutic agents. In the search for anti-tumor agents, research to overcome the drawbacks of high molecular weight and low bioavailability of pure polysaccharides, polysaccharide-conjugated selenium nanoparticles (SeNPs) has attracted much attention.

RESULTS

A novel polysaccharide-selenium nanoparticle complex was produced, in which SeNPs were decorated with polysaccharide obtained from fermented mycelia broth of Lactarius deliciosus (FLDP). Transmission electron microscope, dynamic light scattering, and X-ray photoelectron spectroscopy were utilized to characterize the FLDP-SeNPs; and human hepatocarcinoma cell line (HepG2) was used to assess growth inhibition efficacy. The FLDP-SeNPs that were prepared had a spherical shape with the smallest mean diameter of 32 nm. The FLDP-SeNPs showed satisfactory dispersibility and stability after combination, demonstrating that a reliable consolidated structure had formed. The results revealed that FLDP-SeNPs had notable growth inhibition effects on HepG2 cells. They reduced the membrane potential of mitochondria significantly, increased the generation of reactive oxygen species, enhanced levels of both Caspase-3 and Caspase-9, and led to the nucleus in a wrinkled form.

CONCLUSION

The FLDP-SeNPs could exert a synergetic toxicity reduction and inhibition enhancement effect on HepG2 cells by inducing early apoptosis, through mitochondria-mediated cytochrome C-Caspases and reactive oxygen species-induced DNA damage pathways. These results indicate that FLDP-SeNP treatment of HepG2 cells induced early apoptosis with synergetic efficacy, showing that FLDP-SeNPs can be useful as natural anti-tumor agents. © 2024 Society of Chemical Industry.

Enhancement of yellow pigments production via high CaCl2 stress fermentation of Monascus purpureus

Monascus pigments (MPs) are a kind of natural ingredient fermented by Monascus spp., which contains three types of pigments: red, orange, and yellow ones. Monascus yellow pigments have a restricted yield and cannot meet industrial application. The method and mechanism of CaCl2 improving yellow pigments production by liquid fermentation of Monascus purpureus M8 were studied in order to overcome the low yield of yellow pigments produced by liquid fermentation. Changes in physiological and biochemical indicators explained the effects of CaCl2 on the production of Monascus yellow pigments from solid fermentation. The intracellular yellow pigments, orange pigments, and red pigments increased by 156.08%, 43.76%, and 42.73%, respectively, with 60 g/l CaCl2 addition to culture medium. The amount of red and orange pigments reduced, while the proportion of yellow pigments increased and the relative peak area of intracellular yellow pigments accounted for a dominant 98.2%, according to thin layer chromatography and high performance liquid chromatography analyses. Furthermore, the influence of CaCl2 extended to the modulation of pigments synthesis-related gene expression in M8 strain. This modulation led to a pronounced upregulation in the expression of the yellow pigments synthesis-related gene, mppE, signifying a pivotal role played by CaCl2 in orchestrating the intricate machinery behind yellow pigments biosynthesis.

Optimization of liquid fermentation conditions for Coprinus comatus to enhance antioxidant activity

Coprinus comatus is an edible and medicinal fungus. In this study, the antioxidant activity of the fermentation product of C. comatus was investigated through optimization of fermentation process. The results indicated that the fermentation product of C. comatus had obvious scavenging ability for 2,2'-Azino-bis(3-ethylbenzothiazoline)-6-sulphonic acid (ABTS) free radical. The EC50 of the n-butanol extract from the fermentation product on ABTS·+ was 0.65 ± 0.02 mg/mL. On this basis, the liquid fermentation conditions of C. comatus were optimized through single factor and response surface optimization experiments according to the scavenging ability of ABTS·+ to improve the antioxidant capacity of the fermentation product. The results showed that when the 14% of C. comatus was fermented in a culture medium with a C/N ratio of 48:1 for 6 days, the ABTS·+ scavenging ability was the strongest, and the EC50 of n-butanol extract was 0.57 ± 0.01 mg/mL, which was 12.31% higher than the initial activity. This study laid the foundation for the development of C. comatus.

Immunomodulatory Effect of Flammulina rossica Fermentation Extract on Healthy and Immunosuppressed Mice

Flammulina rossica fermentation extract (FREP) was obtained by ethanol precipitation of the fermentation broth. The molecular weight of FREP is 28.52 kDa, and it mainly contains active ingredients such as polysaccharides, proteins, reducing sugars, and 16 amino acids. Among them, the polysaccharides were mannose, glucose, galactose, arabinose, and fucose and possessed β-glycosidic bonds. Furthermore, the immunoregulatory activities of FREP were investigated in vivo. The results demonstrated that FREP could increase the counts of CD4+ T lymphocytes and the ratio of CD4+/CD8+ in a dose-dependent manner in healthy mice. In addition, FREP significantly increased serum cytokines, including IL-2, IL-8, IL-10, IL-12, IL-6, IL-1β, INF-γ, C-rection protein, and TNF-α, and promoted splenocyte proliferation in healthy mice. Finally, FREP could restore the counts of white blood cells, red blood cells, secretory immunoglobulin A, and antibody-forming cells and significantly promote the serum haemolysin level in mice treated with cyclophosphamide. The findings indicated that FREP possessed immunoregulatory activity in healthy mice and could improve the immune functions in immunosuppressive mice. Therefore, FREP could be exploited as an immunomodulatory agent and potential immunotherapeutic medicine for patients with inadequate immune function.

Blastospores from Metarhizium anisopliae and Metarhizium rileyi Are Not Always as Virulent as Conidia Are towards Spodoptera frugiperda Caterpillars and Use Different Infection Mechanisms

Infective conidia from entomopathogenic fungi are widely used to control insect pests. Many entomopathogenic fungi also produce yeast-like cells called blastospores under specific liquid culture conditions that can directly infect insects. However, little is known about the biological and genetic factors that allow blastospores to infect insects and make them potentially effective for biological control in the field. Here, we show that while the generalist Metarhizium anisopliae produces a higher number of and smaller blastospores, the Lepidoptera specialist M. rileyi produces fewer propagules with a higher cell volume under high-osmolarity conditions. We compared the virulence of blastospores and conidia of these two Metarhizium species towards the economically important caterpillar pest Spodoptera frugiperda. Conidia and blastospores from M. anisopliae were equally infectious, but acted slower, and killed fewer insects than M. rileyi conidia and blastospores did, where M. rielyi conidia had the highest virulence. Using comparative transcriptomics during propagule penetration of insect cuticles, we show that M. rileyi blastospores express more virulence-related genes towards S. frugiperda than do M. anisopliae blastospores. In contrast, conidia of both fungi express more virulence-related oxidative stress factors than blastospores. Our results highlight that blastospores use a different virulence mechanism than conidia use, which may be explored in new biological control strategies.

Functional Components from the Liquid Fermentation of Edible and Medicinal Fungi and Their Food Applications in China

Functional raw materials rich in various effective nutrients and active ingredients that are of stable quality can be obtained from the liquid fermentation of edible and medicinal fungi. In this review, we systematically summarize the main findings of this comparative study that compared the components and efficacy of liquid fermented products from edible and medicinal fungi with those from cultivated fruiting bodies. Additionally, we present the methods used in the study to obtain and analyze the liquid fermented products. The application of these liquid fermented products in the food industry is also discussed. With the potential breakthrough of liquid fermentation technology and the continued development of these products, our findings can serve as a reference for further utilization of liquid fermented products derived from edible and medicinal fungi. Further exploration of liquid fermentation technology is necessary to optimize the production of functional components from edible and medicinal fungi, and to enhance their bioactivity and safety. Investigation of the potential synergistic effects of combining liquid fermented products with other food ingredients is also necessary to enhance their nutritional values and health benefits.

Addition of Vegetable Oil to Improve Triterpenoids Production in Liquid Fermentation of Medicinal Fungus Antrodia cinnamomea

The liquid fermentation of Antrodia cinnamomea is a promising alternative source for fungus production compared to the wildly grown fruiting body. Elicitation is a strong tool to enhance the productivity in microbial cells to obtain more compounds of interest. In this study, in order to improve the fungus growth and its terpenoids production, various vegetable oils were added in the fermentation broth of A. cinnamomea. It was found that corn oil from a group of vegetable oils exhibited the best effect on the biomass and triterpenoid content. After optimization, the initial addition of 1% (v/v) corn oil plus the inoculation of 10% (v/v) mycelia led to a maximum triterpenoid yield (532.3 mg L⁻¹), which was increased as much as fourfold compared to the blank control. Differential transcriptome analysis demonstrated that corn oil significantly enriched several metabolic pathways including glycolysis/gluconeogenesis, propanoate metabolism and transmembrane hydrophobins. The enriched pathways interacted with deferentially expressed genes (DEGs) induced by corn oil treatment. Our research provides a potential strategy for the large production of triterpenoids by the improved fermentation of A. cinnamomea.

Carbon Source Affects Synthesis, Structures, and Activities of Mycelial Polysaccharides from Medicinal Fungus Inonotus obliquus

The effects of various carbon sources on mycelial growth and polysaccharide synthesis of the medicinal fungus Inonotus obliquus in liquid fermentation were investigated. After 12-d fermentation, mycelial biomass, polysaccharide yield, and polysaccharide content were significantly higher in Glc+Lac group (glucose and lactose used as combined carbon source) than in other groups. Crude polysaccharides (CIOPs) and the derivative neutral polysaccharides (NIOPs) were obtained from mycelia fermented using Glc, fructose (Fru), Lac, or Glc+Lac as carbon source. Molecular weights of four NIOPs (termed as NIOPG, NIOPF, NIOPL, and NIOPGL) were respectively 780.90, 1105.00, 25.32, and 10.28 kDa. Monosaccharide composition analyses revealed that NIOPs were composed of Glc, Man, and Gal at different molar ratios. The NIOPs were classified as α-type heteropolysaccharides with 1→2, 1→3, 1→4, 1→6 linkages in differing proportions. In in vitro cell proliferation assays, viability of RAW264.7 macrophages was more strongly enhanced by NIOPL or NIOPGL than by NIOPG or NIOPF, and proliferation of HeLa or S180 tumor cells was more strongly inhibited by NIOPG or NIOPGL than by NIOPF or NIOPL, indicating that immune-enhancing and anti-tumor activities of NIOPs were substantially affected by carbon source. qRT-PCR analysis revealed that expression levels of phosphoglucose isomerase (PGI) and UDP-Glc 4-epimerase (UGE), two key genes involved in polysaccharide synthesis, varied depending on carbon source. Our findings, taken together, clearly demonstrate that carbon source plays an essential role in determining structure and activities of I. obliquus polysaccharides by regulating expression of key genes in polysaccharide biosynthetic pathway.

Ganoderma sessile is a fast polysaccharide producer among Ganoderma species

The selection of fast-growing and high-yield-producing strains is required to satisfy the market demand on fungal food supplements. To that aim, three strains deposited in our collection as G. lucidum and G. oregonense were screened for polysaccharide production and biomass yield. Ganoderma strains deposited as G. lucidum were identified as G. sessile and G. lingzhi by nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 (ITS) and translation elongation factor 1-α (TEF1-α) phylogenies. The identity of G. oregonense was confirmed by molecular phylogeny and biogeography. Additionally, mycelial antagonism confirmed species differentiation, and strains were further distinguished by morphology and protein profiles. Biomass and polysaccharide yields of G. sessile were clearly different from those of G. lingzhi and G. oregonense in both liquid culture and solid-state fermentation. The maximum polysaccharide yield (4.52 ± 0.83 g L^-1) for G. sessile was obtained from submerged cultures at day 9. G. sessile also achieved the highest linear growth in lignocellulosic solid substrates. Consequently, basidiomata were successfully obtained by solid-state fermentation in polypropylene bags, whereas G. lingzhi and G. oregonense mushrooms were not produced in artificial solid substrates. G. sessile, a species frequently collected in America, showed to be a promising polysaccharide producer for the manufacture of dietary supplements.

Transcriptional Responses of Beauveria bassiana Blastospores Cultured Under Varying Glucose Concentrations

Culturing the entomopathogenic fungus, Beauveria bassiana, under high glucose concentrations coupled with high aeration results in a fungal developmental shift from hyphal growth to mostly blastospores (yeast-like cells). The underlying molecular mechanisms involved in this shift remain elusive. A systematic transcriptome analysis of the differential gene expression was preformed to uncover the fungal transcriptomic response to osmotic and oxidative stresses associated with the resulting high blastospore yield. Differential gene expression was compared under moderate (10% w/v) and high (20% w/v) glucose concentrations daily for three days. The RNAseq-based transcriptomic results depicted a higher proportion of downregulated genes when the fungus was grown under 20% glucose than 10%. Additional experiments explored a broader glucose range (4, 8, 12, 16, 20% w/v) with phenotype assessment and qRT-PCR transcript abundance measurements of selected genes. Antioxidant, calcium transport, conidiation, and osmosensor-related genes were highly upregulated in higher glucose titers (16-20%) compared to growth in lower glucose (4-6%) concentrations. The class 1 hydrophobin gene (Hyd1) was highly expressed throughout the culturing. Hyd1 is known to be involved in spore coat rodlet layer assembly, and indicates that blastospores or another cell type containing hydrophobin 1 is expressed in the haemocoel during the infection process. Furthermore, we found implications of the HOG signaling pathway with upregulation of homologous genes Ssk2 and Hog1 for all fermentation time points under hyperosmotic medium (20% glucose). These findings expand our knowledge of the molecular mechanisms behind blastospore development and may help facilitate large-scale industrial production of B. bassiana blastospores for pest control applications.

[Advances in biosynthesis of cordycepin from Cordyceps militaris]

Cordycepin as the main active ingredient of Cordyceps militaris, a traditional medicinal fungus in China, has many physiological functions such as anti-cancer, anti-tumor and anti-virus activity. The most potential route for effective cordycepin production has been considered as liquid fermentation of C. militaris though with low productivity at present. Thus, it is urgent to apply both process engineering strategy and metabolic engineering strategy to enhance the productivity of cordycepin. In this review, the effects of medium components (i.e. the carbon/nitrogen source, precursor substances and metal ions) and operation factors (i.e. pH, dissolved oxygen and light) on cordycepin biosynthesis in liquid fermentation system are summarized. Besides, separation of cordycepin, the gene cluster involved and predicted biosynthesis pathways of cordycepin are also discussed, providing possible solutions of finally realizing efficient production of cordycepin.

Safety Assessment of HEA-Enriched Cordyceps cicadae Mycelium: A Randomized Clinical Trial

Objective: Cordyceps cicadae, a medicinal fungus, is assessed as having many functions: anti-cancer, anti-fatigue, anti-aging, immune-boosting, renal and liver protection. Since the industrial production of C. cicadae mycelium consistently manufactures bioactive compounds superior to wild fruiting bodies, there is a need to confirm the toxicity of liquid fermented C. cicadae mycelium. Studies showed the toxicity evaluation of C. cicadae mycelium in animal models, but safety reports in clinical studies are scarce. As such, a safety assessment of oral N6-(2-hydroxyethyl) adenosine (HEA-enriched) C. cicadae mycelium in humans is provided here.Method: After 49 participants ingested granules of 1.05 g of freeze-dried C. cicadae mycelium once a day for 3 months, their blood samples were collected at the beginning and end of the experiment for analysis.Results: There were no significant differences between the initial and final measurements in renal and liver function. Also, there was no influence on blood electrolytes as well as blood lipid levels. In clinical observation, there were also no side effects or adverse feelings mentioned by participants.Conclusion: These results suggested that HEA-enriched C. cicadae mycelium produced by liquid fermentation is safe and can be developed as a functional health food.

Novel liquid fermentation medium of Cordyceps militaris and optimization of hydrothermal reflux extraction of cordycepin

In this study, we developed a novel liquid fermentation medium of Cordyceps militaris using pupa powder and wheat bran as nitrogen resources instead of the traditionally used peptone. This process not only reduced the cost by approximately 50%, but increased production by over 30%. Then, we explored a method to extract and purify cordycepin by combining hydrothermal reflux extraction with macroporous resin adsorption, which is inexpensive and suitable for the industrial production. The optimum conditions for hydrothermal reflux were extracting three times at 95 °C with 1:10 sample-to-water ratio, and the cordycepin purity with macroporous resin HPD-100 reached 95.23%.[Formula: see text].

Analysis of Chuanxiong Rhizoma substrate on production of ligustrazine in endophytic Bacillus subtilis by ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry

Ligustrazine was the active ingredient of the traditional Chinese medicine Chuanxiong Rhizoma. However, the content of ligustrazine is very low. We proposed a hypothesis that ligustrazine was produced by the mutual effects between endophytic Bacillus subtilis and the Ligusticum chuanxiong Hort. This study aimed to explore whether the endophytic B. subtilis LB5 could make use of Chuanxiong Rhizoma fermentation matrix to produce ligustrazine and clarify the mechanisms of action preliminarily. Ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry analysis showed the content of ligustrazine in Chuanxiong Rhizoma was below the detection limit (0.1 ng/mL), while B. subtilis LB5 produced ligustrazine at the yield of 1.0268 mg/mL in the Chuanxiong Rhizoma-ammonium sulfate fermentation medium. In the fermented matrix, the reducing sugar had a significant reduction from 12.034 to 2.424 mg/mL, and rough protein content increased from 2.239 to 4.361 mg/mL. Acetoin, the biosynthetic precursor of ligustrazine, was generated in the Chuanxiong Rhizoma-Ammonium sulfate (151.2 mg/mL) fermentation medium. This result showed that the endophytic bacteria B. subtilis LB5 metabolized Chuanxiong Rhizoma via secreted protein to consume the sugar in Chuanxiong Rhizoma to produce a considerable amount of ligustrazine. Collectively, our preliminary research suggested that ligustrazine was the interaction product of endophyte, but not the secondary metabolite of Chuanxiong Rhizoma itself.

Chemical Constituent Profiling of Paecilomyces cicadae Liquid Fermentation for Astragli Radix

Astragli Radix (AR) is one of the most popular traditional Chinese medicines with chemical constituents including flavonoids and saponins. As recently evidenced, some fungi or their fermentation liquid may have the potential to affect the bioactive constituents and different pharmacological effects of AR. Thus, the composition of fermented AR (FAR) produced by Paecilomyces cicadae (Miquel) Samson in liquid-state fermentation was investigated using a UHPLC-LTQ-Orbitrap mass spectrometer in both positive and negative ion modes. Firstly, the MSⁿ data sets were obtained based on a data-dependent acquisition method and a full scan–parent ions list–dynamic exclusion (FS-PIL-DE) strategy. Then, diagnostic product ions (DPIs) and neutral loss fragments (NLFs) were proposed for better constituent detection and structural characterization. Consequently, 107 constituents in total, particularly microconstituents in FAR and AR, were characterized and compared in parallel on the same LTQ–Orbitrap instrument. Our results indicated that AR fermentation with Paecilomyces significantly influenced the production of saponins and flavonoids, especially increasing the content of astragaloside IV. In conclusion, this research was not only the first to show changes in the chemical components of unfermented AR and FAR, but it also provides a foundation for further studies on the chemical interaction between microbiota and AR.

Isolated from Southwest China

Morels famous for their taste and nutrition are in short supply all over the world although they were considered as one of the most highly prized edible and medicinal mushrooms. Because of the limitation of resource and cultivation technology, fermentation of edible mushroom was gradually applied to nutrient, bioactivity and breeder seed preparation. At present, there are more reports on sugar and amino acid but less on other components. Morchella sp. YDJ-ZY-1 was isolated from the wild fruiting body by the spores releasing method in Zunyi Guizhou province in Southwest China and identified based on phenotype and genotype characteristics. Chemical compositions of YDJ-ZY-1 were investigated from liquid fermentation that will lay the foundation for further development and utilization. Four pyranoids (1–4) and 2-(1-oxo-2-hydroxyethyl) furan (5), linoleic acid (6), Morelin (2-hydroxy-cinnamic acid methyl ester, (7) and 1-O-β-d-ribofuranose-Morelin (8) were obtained from EtOAc extraction and elucidated by spectral data. Product 4 and 8 were new compounds and 7 was isolated from nature for the first time. Antiradical activity was evaluated by free radical scavenging effect on DPPH (1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl). Compound 5 exhibited strong antiradical activity while compounds 1 and 2 exhibited moderate activity. Thus, incubation of Morchella sp YDJ-ZY-1 separated from the wild fruit body afforded eight compounds. Secondary metabolites with new structures were mined from fermentation of Morchella sp. and antiradical activity was evaluated.

Growth performance, gastrointestinal and digestibility responses in growing pigs when fed corn-soybean meal-based diets with corn DDGS treated with fiber degrading enzymes with or without liquid fermentation

Fermenting high fiber ingredients such as distillers dried grains with solubles (DDGS) with feed enzymes may improve their feeding value. We investigated the effects of fermenting corn DDGS with a blend of β-glucanase and xylanases (XB) on growth performance, gut parameters, and apparent total tract digestibility (ATTD) of nutrients and energy in growing pigs. Dietary treatments were: (1) corn soybean meal-based diet + 30% DDGS (control), (2) control + XB without fermentation (XBNS), and (3) control + DDGS fermented with XB (16% DM) for 3 to 10 d at 40 °C (XBS). Target activities in XB were 1,050 and 5,500 U/g of DDGS for XB, respectively. Diets contained phytase at 750 FTU/kg. Feed samples were taken during fermentation and at feeding for analysis of pH and organic acids. A total of 144 pigs (25 ± 1.0 kg BW) were assigned to pens (three barrows and three gilts) and allocated to the three diets in a two-phase feeding program (3 wk/phase). Diets were fed on ad libitum and were delivered by a computer-controlled liquid feeding system at a feed to water ratio of 1:4, four times per day. Pigs had free access to water. Fecal samples were taken in the final 3 d of phase 2 to determine ATTD using TiO2 marker method and one pig per pen was euthanized for gastrointestinal (GIT) measurements. The pH of diets at feeding time was lower (P < 0.01) for XBS (4.72) compared with control (5.45) and XBNS (5.45). Pigs fed XBNS had higher (P = 0.04) ADG than control in phase 1. In phase 2 and the overall (weeks 0 to 6), ADG and final BW were higher (P = 0.01) for XBNS than XBS but were not different (P > 0.05) from control. There were no diet effects (P > 0.05) on ADFI. Feed to gain (FCR) for XBNS (1.68) and XBS pigs (1.69) was better (P < 0.01) than for control pigs (1.78) in phase 1. There were no diet effects (P > 0.05) on FCR in phase 2 or in the overall. Pigs fed XBNS had lower (P < 0.01) ATTD of CP than control and XBS-fed pigs. Although not different (P > 0.05) from control, pigs fed XBNS had lower (P < 0.05) jejunal crypt depth and ATTD of gross energy than pigs fed XBS. In conclusion, treating corn DDGS with XB with or without liquid fermentation improved feed efficiency in phase 1, suggesting degradation of dietary fibrous components that may limit nutrient utilization in younger pigs. However, these benefits were not observed in phase 2.

Fermentation: A Boon for Production of Bioactive Compounds by Processing of Food Industries Wastes (By-Products)

A large number of by-products or wastes are produced worldwide through various food industries. These wastes cause a serious disposable problem with the environment. So, now a day's different approaches are used for alternative use of these wastes because these by-products are an excellent source of various bioactive components such as polyphenols, flavonoids, caffeine, carotenoids, creatine, and polysaccharides etc. which are beneficial for human health. Furthermore, the composition of these wastes depends on the source or type of waste. Approximately half of the waste is lignocellulosic in nature produced from food processing industries. The dissimilar types of waste produced by food industries can be fortified by various processes. Fermentation is one of the oldest approaches and there are three types of fermentation processes that are carried out such as solid state, submerged and liquid fermentation used for product transformation into value added products through microorganisms. Selections of the fermentation process are product specific. Moreover, various studies were performed to obtain or fortified different bioactive compounds that are present in food industries by-products or wastes. Therefore, the current review article discussed various sources, composition and nutritive value (especially bioactive compounds) of these wastes and their management or augmentation of value-added products through fermentation.

The Effects of Nutrient Concentration, Addition of Thickeners, and Agitation Speed on Liquid Fermentation of Steinernema feltiae

Entomopathogenic nematode production in liquid fermentation still requires improvements to maximize efficiency, yield, and nematode quality. Therefore, this study was aimed at developing a more suitable liquid medium for mass production of Steinernema feltiae, by assessing the effects of nutrient concentration, thickeners (primarily agar), and agitation speed on infective juvenile (IJ) yield. Base medium (BM) contained yeast extract (2.3%), egg yolk (1.25%), NaCl (0.5%), and corn oil (4%). All media were inoculated with Xenorhabdus bovienii, and 2 d later, with 2-d-old S. feltiae juveniles. For the nutrient concentration experiment, we evaluated the base medium versus a modified base medium containing all the components, but with 3× concentrations of yeast extract (6.9%), egg yolk (3.75%), and corn oil (12%). The nematodes and bacteria were cultured in 150-ml Erlenmeyer flasks containing 50 ml of liquid medium at (25°C) and 180 rpm on a rotary shaker incubator. To assess the effect of thickeners, IJs were inoculated in BM with agar (0.2%), carrageen (0.2%), and carboxymethyl cellulose (0.2% and 0.5%). The addition of 3× more nutrients relative to the BM resulted in a significantly lower yield of nematodes. For agar and agitation speed experiments, five levels of agar in the BM (0%, 0.2%, 0.4%, 0.6%, and 0.8% agar) and two agitation speeds (180 and 280 rpm) were evaluated for production. Increasing agitation speed from 180 to 280 rpm and higher levels of agar in the medium (> 0.2%) significantly increased the yield of bacteria. At the lower agitation speed, media amended with 0.4% and 0.6% agar produced higher nematode yields compared to media without agar. Media with 0.2% and 0.8% agar resulted in intermediate levels of nematode production. At the higher agitation speed, media supplemented with 0.8% agar resulted in the lowest yield of nematodes when compared to the other media tested. Results indicated that increasing nutrient concentration levels was detrimental to nematode production. Also, media containing agar (0.4% and 0.6%) increased nematode yields when cultures were grown at low agitation speed. When IJs were used as the inoculum, 0.2% agar also enhanced recovery and nematode yield at the higher agitation speed.