Acid Hydrolyzed Research Articles

Bioethanol Production from Ammonia Pretreated Rice Straw

Rice straw is produced in large quantity throughout the world. Rice straw is a leading feedstock for bioethanol production. Diluted ammonia pretreatment for one week at room temperature was found to be effective pretreatment. This pretreated rice straw was acid hydrolyzed and subsequently fermented with Saccharomyces cerevisiae CP11 strain. 1.5% ammonia pretreatment at room temperature for one week resulted 82.4% delignification and 78.49% of acid hydrolysis. Acid hydrolysate was fermented with maximum ethanol concentration 5.70 % with an ethanol yield of 0.46g/g and fermentation efficiency of 90.6%. Diluted ammonia pretreatment at higher temperature has reduced delignification, saccharification and fermentation efficiency with more phenols and furfurals.

Bioethanol production from grass pea and wild oat hydrolysates using S.cerevisiae ETP53, K. marxianus ETP87, and P. fermentans ETP22

Conversion of lignocellulosic biomass into bioethanol is essential to reduce dependency on fossil fuels. After the grass pea and wild oat straws were characterized, they were hydrolyzed by live fungi (in situ), crude fungal enzymes, and chemical methods (sodium hydroxide and sulphuric acids at 0.5, 1, 2, and 3%). The fungi used for in situ degradation and crude lignocellulosic enzymes were Aspergillus niger JMC22344, Trichoderma reesei JMC22, Pleurotus ostreatus M2191, and Pleurotus sajor-caju M2145. Furfural content of hydrolysates was analyzed by GC–MS. The potential of activated charcoal, overliming, and sequential activated charcoal-overliming potential to reduce furfural in the acid hydrolysates were evaluated. The hydrolysates were fermented by S. cerevisiae ETP53, K. marxianus ETP87, and P. fermentans ETP22. Sulphuric acid hydrolyzed common wild oat (8.91 g/L) yielded higher sugars than NaOH (3.88 g/L) and NaOH treated wild oat (8.14 g/L) was superior in terms of sugars released than grass pea (4.21 g/L). P. ostreatus M2191 liberated the highest sugar (18.63 g/L) extracts than T. reesei JMC22676, A. niger ETP22344 and P. sajor-caju M2145. The 23–77% of the furfural in acid hydrolysates was reduced by overliming, activated charcoal, and the sequential activated charcoal-overliming. Yeasts produced optimal ethanol from straws hydrolyzed by crude enzymes from A. niger JMC22344. Generally, the ethanol titer was directly proportional to the amount of sugars released.

Deciphering operation of tryptophan-independent pathway in high indole-3-acetic acid (IAA) producing Micrococcus aloeverae DCB-20.

Genus Micrococcus is considered a high IAA producer. However, interestingly, there is no report on the tryptophan- independent pathway operation in this genus. Consequently, the present study was undertaken to evaluate high IAA production by Micrococcus aloeverae DCB-20 and generate reasonable evidence for the occurrence of the tryptophan-independent pathway. Strain DCB-20 produced a high quantity of 880.51 µM or 154.3µg/mL IAA in LB broth supplemented with L-tryptophan. The tryptophan-independent pathway operation was supported by IAA production in Tris-minimal broth (TM broth) medium supplemented with acid hydrolyzed casein hydrolysate (casein acid hydolysate), which lacks tryptophan. The HPLC analysis showed the absence of tryptophan either from exogenous or endogenous sources in TM broth in the presence of casein acid hydrolysate inoculated with M. aloeverae DCB-20. The absence of tryptophan was further confirmed by the appearance of non-pigmented colonies of Chromobacterium violaceum strain TRFM-24 on Tris-minimal agar (TM agar) containing acid-hydrolyzed casein. This is probably the first report on IAA biosynthesis by M. aloeverae DCB-20 employing tryptophan-independent pathway. This simple technique can also be adapted to detect operation of the tryptophan-independent pathway in other bacteria.

Detoxification of sisal bagasse hydrolysate using activated carbon produced from the gasification of açaí waste

Due to its recalcitrance and difficult disruption, biomass requires severe treatment conditions to produce bioproducts. These processes also generate substances that inhibit microbial metabolism, resulting in low conversion of sugars into bioproducts. To minimize this, in this work the sisal bagasse acid hydrolysate was detoxified using the activated carbon obtained from residues of the gasification of açaí endocarp. The adsorbent properties were analyzed, and the effects of experimental parameters related to furfural adsorption were evaluated. Then, the validation of the adsorption experiments was carried out in acid hydrolyzed liquor from sisal bagasse, the fermentation tests being performed with Saccharomyces cerevisiae. Overall, the furfural adsorption in the activated carbon was fast since most of the furfural was removed in the first minutes of the experiment. The Sips isotherm fit the experimental data best, with maximum adsorption capacity of 48.02 mg.g−1. Kinetic data fitted LDF, QDF and FD models, and diffusivity parameters were obtained. After detoxification, the activated carbon from açaí waste removed 52% of furfural, 100% of HMF and 40.4% of acetic acid with moderate loss of sugars (17%). The results confirmed that the adsorbent is effective and promising for removing furfural and other fermentation inhibitors.

Effects of hydrolytic conditions on recovery of antioxidants from methanolic extracts of Nigella sativa seeds

Nigella sativa (NS) has health promoting beneficial properties including antioxidant activity. In this study, the impact of acid and alkaline hydrolysis conditions on phenolic (TPC), flavonoid (TFC) contents and antioxidant activity of methanolic extracts from N. sativa (NS) seeds powder is evaluated. Total phenolic and flavonoid contents were evaluated according to Folin-Ciocalteu procedure and aluminium chloride colorimetric assays, respectively. The TPC extracts varied from 67 to 73 mg/100 g NS powder, expressed as Gallic acid equivalents (GAE), while TFC concentrations varied from 96 to 113 mg rutin equivalents (RE)/100 g NS powder. Positive correlations were found between TPC and TFC in NS hydrolyzates and their1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (r2 = 0.975 and 0.978, respectively). The alkaline hydrolyzed extract (BHE) showed the highest TPC and TFC (730 µg GAE and1130 µg RE/g NS powder, respectively) as well as the highest antioxidant activity (DPPH• =167±0.133 mg TEAC /100 g dry NS, ABTS•+=112 ± 0.023 mg TEAC /100 g dry NS and FRAP=28 ± 0.159 mg GAE/100 g dry NS) compared to acid hydrolyzed (AHE) and non-hydrolyzed extracts (NHE). Non-hydrolyzed extracts showed the lowest TPC and TFC content (670 µg GAE and 960 µg RE/g NS powder, respectively) through the assays (p < 0.05). Findings of the study reveal that hydrolysis has profound effects on recovery of antioxidants from NS extracts. Overall, BHE has the highest antioxidant activity compared to AHE or NHE. Key words: Nigella sativa, methanolic extracts, hydrolysis, total phenolic content, total flavonoid content, antioxidant activity.

Simultaneous Cellulase Production, Saccharification and Detoxification Using Dilute Acid Hydrolysate of S. spontaneum with Trichoderma reesei NCIM 992 and Aspergillus niger

Bioethanol production from lignocellulosic materials has several limitations. One aspect is the high production cost of cellulases used for saccharification of substrate and inhibition of fermenting yeast due to inhibitors released in acid hydrolysis. In the present work we have made an attempt to achieve simultaneous cellulases production, saccharification and detoxification using dilute acid hydrolysate of Saccharum spontaneum with and without addition of nutrients, supplemented with acid hydrolyzed biomass prior to inoculation in one set and after 3 days of inoculation in another set. Organisms used were T. reesei NCIM 992, and Aspergillus niger isolated in our laboratory. Cellulase yield obtained was 0.8IU/ml on fourth day with T. reesei. Sugars were found to increase from fourth to fifth day, when hydrolysate was supplemented with nutrients and acid hydrolyzed biomass followed by inoculation with T. reesei. Phenolics were also found to decrease by 67%.

MECHANISM OF ANTIFERTILITY IN MALE RATS TREATED WITH 3-MONOCHLORO-1,2-PROPANEDIOL (3-MCPD)

3-Monochloro-1,2-propanediol (3-MCPD) is a food contaminant that is often found in foods containing acid-hydrolyzed (AH) protein, like seasonings and savory food products. The purpose of the present study was to investigate the effects of 3-MCPD on male fertility, sperm, and hormonal levels and its antifertility mechanism. In vivo male fertility testing was performed to observe the adverse effects of 3-MCPD on the functioning of the male reproductive system and pregnancy outcome. 3-MCPD (0.01–5 mg/kg) was administered daily by gavage to Sprague-Dawley (SD) male rats for 4 wk. At the end of the pretreatment period, male rats were mated overnight with untreated females. Males successfully inducing pregnancy were sacrificed to assess sperm parameters, reproductive organ histopathology, and spermatogenesis. The resulting pregnant females were sacrificed on 20 of gestation to evaluate pregnancy outcome. The paternal administration of 3-MCPD (5 mg/kg) was found to result in adverse effects on male fertility and pregnancy outcome without inducing remarkable histopathological changes in testes and epididymides. Additionally, 3-MCPD (5 mg/kg) significantly reduced sperm motility, copulation, fertility indices, and the number of live fetuses showed steep dose-response curves. 3-MCPD did not affect spermatogenesis or induce hormonal changes in the blood and testes of male rats. An in vitro hormone assay using primary isolated Leydig cells showed no significant changes in related hormone levels after 3-MCPD treatment. To evaluate the effects of 3-MCPD on apoptotic induction and H+-ATPase levels in the testis and epididymis, 10 or 100 mg/kg of 3-MCPD was administered by gavage to male rats and testes and epididymides were examined at 3, 6, 12, and 24 h later. Apoptosis was not detected in the testes of animals treated with 100 mg/kg 3-MCPD. However, the level of H+-ATPase in the cauda epididymis was reduced by 3-MCPD treatment. These results indicate that 3-MCPD induced a spermatotoxic effect, which was mediated by reduced H+-ATPase expression in the cauda epididymis, and suggest that an altered pH level in the cauda epididymis might lead to a disruption of sperm maturation and the acquisition of motility.

DETERMINATION OF FUROSINE IN HYDROLYZATE OF PROCESSED MILK BY HPLC USING A NARROW BORE COLUMN AND DIODE-ARRAY DETECTOR

A simple, rapid, sensitive, reproducible, and accurate HPLCprocedure employing a narrow bore reversed phase column and a diode-arraydetector is proposed for the determination of ϵ-N-2-furoylmethyl-L-lysine(furosine) in acid hydrolyzed of milk and powdered milk samples. After optimization of the variables involved, the method was characterizedand validated in terms of selectivity, repeatability, sensitivity, and accuracyand applied to determine furosine content in hydrolyzed milk samples.

Use of agricultural wastes for xanthan production by Xanthomonas campestris

Four different acid-hydrolyzed wastes, from melon, watermelon, cucumber and tomato were compared for xanthan production. Growth of Xanthomonas campestris, xanthan biosynthesis, kinetics and chemical composition were investigated. Both growth and xanthan production were dependent on the acid hydrolysate concentrations and available nitrogen. Melon acid hydrolyzed waste was the best substrate for xanthan production. Exopolysaccharide obtained throughout this study was compared to commercial xanthan, showing a very similar chemical composition. Acid hydrolyzed wastes are proposed as a new carbon source for xanthan production.

Analysis of ε-N-2-Furoylmethyl-L-lysine (Furosine®) in Concentrated Milk by Reversed Phase Chromatography with A Microbore Column

This paper reports the results of a study aimed to develop a rapid, accurate and sensitive HPLC method for routine analysis of ε-N-2-furoylmethyl-L-lysine (furosine) in acid hydrolyzed of processed food products. The method uses a microbore reversed phase HPLC column packed with a polymer coated silica-based octadecyl sorbent (5 μm, 250 × 1 mm I.D) eluted with a mobile phase consisting of 20 mM phosphate buffer, at pH 2.5. The identification of furosine was performed by UV detection at 280 nm in a micro flow cell of 300 nL. The limit of detection was 0.3 ng based on a signal to noise ratio of 3 with a sample volume of 0.5 μL. The separation was achieved by isocratic elution within 15 min. This method was successfully applied to the identification and quantitative determination of furosine in a sample of concentrated milk hydrolyzed with hydrochloric acid. Dosage was performed by the method of external standard.

Characteristics of Acid Hydrolysate from Defatted Peanut Flour

ABSTRACTWe hypothesized that aflatoxin‐contaminated defatted peanut flour could be acid hydrolyzed to produce an aflatoxin‐free seasoning sauce. Physical and chemical properties and amino acid composition of the flour hydrolyzed at 120°C for 4 hr with 5N HCI and destruction of aflatoxin B, during hydrolysis were investigated. The pH (5.72), specific gravity (1.20), total solids (402 mg mL‐1), and reducing sugar (2.9 mg mL‐1) and total nitrogen (17.5 mg mL‐1) contents of the peanut hydrolysate were similar to those of commercial soy sauces or seasoning sauces made by chemical processes. Glutamic acid, aspartic acid, arginine and glycine were the major amino acids in the hydrolysate and should contribute substantially to enhancing flavor. Aflatoxin B, was totally destroyed during acid hydrolysis at 100 or 120°C.

In Vitro Culture of the Monocot Narcissus triandrus L. cv. Thalia

Sterile culture of excised daffodil tissue, Narcissvs triandrgs L. cz. Thalia, was attempted on 12 media. Callus tissue and bulbets formed by differentiation of callus tissue proliferated only on media of high auxin levels. Evidence of alkaloid production by these cultures was obtained. Callus tissues growing on sterile media have provided experimental materials for many fundamental and applied investigations of higher plants. Somatic tissue from a wide variety of dicotyledonous plants have been grown iv vitro as callus, but most attempts to culture comparable tissues from Inonocotyledonous plants have been unsuccessful. With the recent reports of in ?vitro culture of somatic wheat callus tissue (1 ) and of sugar cane cells (2) ¢nly a few successful reports of previously cultured monocotyledonous tissues other than endosperm are available. The present communication deocribe3 a n.etllod for c)btaining callus cultures of daffodil tissue and preliminary investigations of its metabolic capabilities. Commercial (3) bulbs of Nczrciss triandAs L. cv. Thalia were vernalized fcor six weeks at 4°C. The bulbs were peeled of excess scales, surface sterilized with saturated calcium hypochlorite solution, rinsed three times with sterile distilled water, cut into pieces of approximately one gram weight and implanted on the selected medium. Twelve modiScations of the medium described by Murashige and Skoog (At) were tested. The medium selected for maintenance of the cultures was Murashige and Skoog's basal medium with 10 mg per liter of naphthalene acetic acid, 1 mg per liter of kinetin and 1 mg per liter of gibberellic acid. Variations consisted of changing the ratios of auxin (both naphthalene acetic acid and indole acetic acid) to kinetin and the addition of gibberellic acid and casein hydrolysate (both enzymatic and acid hydrolyzed). The cultures were grown at 27° in the dark in 125 Erlenmeyer flasks containing approximately 50 ml of agar medium. These were initially observed for growth and subcultured to fresh media when two to three fold growth had occurred. A comparison of the times Transactions of the Kansas Academy of Science, Vol. 74, No. 1, 1971. Published January 7, 1972. 1 This srork was supported in part by funds provided to the University of Kansas by the National Institutes of Health Biomedical Sciences Support Grant.