Yeast Hydrolysate Research Articles

Yeast hydrolysate supplement increases starvation vulnerability of Queensland fruit fly

AbstractPost‐teneral diets containing yeast hydrolysate are reported to increase longevity, reproductive development and sexual performance of Queensland fruit fly (‘Q‐fly’) Bactrocera tryoni Froggatt (Diptera: Tephritidae). Consequently, diets including yeast hydrolysate are recommended for sterile Q‐flies before release in sterile insect technique (SIT) programmes. However, in some tephritids, diets including yeast hydrolysate are associated with an increased vulnerability to starvation. In the present study, the effects of yeast hydrolysate supplementation before release are considered with respect to the longevity of released Q‐fly when food becomes scarce. Experiments are carried out in three settings of varying resemblance to field conditions: 5‐L laboratory cages, 107‐L outdoor cages and 14 140‐L field cages containing potted citrus trees. In all experimental settings, compared with flies that received only sucrose, male and female Q‐flies that are provided with yeast hydrolysate during the first 2 days of adult life have a significantly shorter survival when subsequently deprived of food. Yeast supplementation appears to commit Q‐flies to a developmental trajectory that renders them more vulnerable to starvation. The practical significance of these findings for SIT depends on how often the releases are carried out under conditions in which Q‐flies experience extreme food shortages in the field.

English

  The present study was designed to investigate the hypoglycemic effects of the daily oral dose of 0.50 to 0.75 g/kg of yeast hydrolysate (YH) containing high Cyclo-His-Pro (51.0 mg CHP/g YH) on normal and streptozotocin (STZ)-induced diabetic rats for 14 days. In STZ-induced diabetic rats, after administrations of the YH for 14 days, the body weight gain was significantly increased in dose dependent manner, and the plasma glucose levels were decreased approximately (60%) as compared to the STZ induced diabetic control group. Glucose level showed significant differences between the diabetic control (DC) and the YH administered groups in oral glucose tolerance test (OGTT) (P<0.05). Results of the OGTT showed a significant decrease in the area under curve (AUC) value of YH supplemented groups as compared to the DC group. The present data suggests that the CHP-enriched YH has potential anti-diabetic effect, which can help in the cure and management of diabetes.   Key words: Yeast hydrolysate, Cyclo-His-Pro (CHP), diabetes, streptozotocin.

Influence of culture conditions on lipid production by Candida sp. LEB-M3 using glycerol from biodiesel synthesis

Abstract The goal of this work was to use glycerol produced from biodiesel synthesis to grow Candida sp. LEB-M3 and select significant variables of culture conditions on lipid production. This yeast was isolated from a Brazilian biome which showed capacity to accumulate up to 55% lipids (w/w) and convert about 43% of glycerol into lipids. Production and lipid profile at different growth temperatures were studied. The experimental design showed that glycerol, FeCl 3 ·6H 2 O, yeast hydrolyzate and temperature were significant on the lipid production. Cultivation at 23 °C promoted the highest concentration of lipids about 9.9 g/L. However, the lipid profiles for the different growth temperatures were similar, with high concentrations of linoleic acid (C18:2) (∼45–55%) and smaller amount of gamma linolenic acid (C18:3) (∼2–5%), both essential fatty acids, leading to the conclusion that lipid produced by Candida sp. LEB-M3 has potential to be used both as a feedstock for biodiesel production or as a source for essential fatty acids.

L(+)-Lactic acid production from furfural residues and corn kernels with treated yeast as nutrients

In this study, Streptococcus thermophilus and Lactobacillus bulgaricus were used to produce l(+)-lactic acid by simultaneous saccharification and fermentation (SSF). The use of hydrolyzed yeast as cheap nutrients and mixtures of cellulosic materials and starchy materials as carbon source for l(+)-LA production was evaluated. Heat treatment (121 °C) was proven to be an effective method to improve the performances of yeast as nutrients for the fermentations using different carbon sources. The addition of yeast hydrolyzate obviously lowered the surface tension of medium and improved enzyme hydrolysis of furfural residue (FR) as the concentration was beyond 10 g/L. Carbon–nitrogen ratio, substrates composition, substrates feeding rate and enzyme-feeding strategy will affect the productivity of l(+)-LA production from mixed substrates. SSF of FR and corn saccharification liquid tends to obtain good yields, when the total WIS content is in 10 % and carbon–nitrogen ratio is about 30. This study provides an encouraging means of producing l(+)-LA from lignocellulosic resource and starchy resource, which could optimize the use of raw materials.

Combination of yeast hydrolysates to improve CHO cell growth and IgG production

Many studies underlined the great benefits of hydrolysates used as additives in animal free media on cell culture performances. However, to precisely define hydrolysate supplementation strategies, a deeper understanding of their effect on cell growth and protein production is required. In the present study, the effect of addition of one yeast extract (YE) and two yeast peptones (named YP.A and YP.B) in a chemically defined medium was first assessed on cell culture performances. Interestingly, specific effects were found depending on the degree of degradation of yeast hydrolysates. The YE at 1g L(-1) increased the maximal cell density by 70%, while a mixture of YE (1g L(-1)) and YP.A (4g L(-1)) increased IgG production by 180%. These conditions were then evaluated on the CHO cell kinetics all over cultures. Hydrolysates extended the cell growth phase in Erlenmeyer flask and increased the maximal growth rate in bioreactor up to 20%. Cell growth stimulation induced by hydrolysates addition was linked with energetic metabolism improvement suggesting that they promote oxidative pathway. Furthermore, hydrolysates provided an additional source of substrate that supported cell growth despite glutamine limitation.

Yeast Hydrolysate Protects Cartilage via Stimulation of Type II Collagen Synthesis and Suppression of MMP‐13 Production

Type II collagen (COL II) is one of the primary components of hyaline cartilage and plays a key role in maintaining chondrocyte function. COL II is the principal target of destruction, and matrix metalloproteases (MMPs) have a major role in arthritis. In the present study, we investigated the chondroctye protection effects of specific fraction of yeast hydrolysate ((10-30 kDa molecular weight peptides). The mRNA expression of COL II was significantly increased in the YH-treated group compared to the control at concentrations above 50 µg/ml, respectively. The 200 µg/ml YH-treated group (3.43 ± 0.23 µg/ml) showed significantly reduced glycosaminoglycan (GAG) degradation relative to that in the interleukin-1β (IL-1β)-treated control group (4.72 ± 0.05 µg/ml). In the YH-treated group, MMP-13 level was significantly decreased in a dose-dependent manner compared to the IL-1β-treated group without YH treatment. However, MMP-1 and MMP-3 level were not different from that of control. Under the same conditions, we also examined mRNA levels of COL II. The mRNA expression of COL II was significantly higher in the YH-treated group than in the IL-1β-treated control group at concentrations above 100 µg/ml. In conclusion, YH stimulated COL II synthesis and significantly inhibited MMP-13 and GAG degradation caused by IL-1β treatment.

Thermal stability of yeast hydrolysate as a novel anti-obesity material

We examined the thermal stability of yeast hydrolysates before and after ultrafiltration (UF) in vitro, and the anti-obesity activity of yeast hydrolysates before and after heat treatment in vivo. Yeast hydrolysate after UF showed significantly higher thermal stability than before UF. Yeast hydrolysates before and after UF showed 3 and 4 thermal transition peaks in their thermograms, respectively, and the total thermal denaturation enthalpies of yeast hydrolysates before and after UF were 69.5 and 36.5J/g, respectively. For the anti-obesity activity study, yeast hydrolysates before and after heating were administered ad libitum with water to 7-week-old male SD rats. The administration of yeast hydrolysate (YH-control; no heat treatment, YH-1; heat treatment at 140°C, and YH-2; heat treatment at 160°C) significantly increased mRNA expression of cocaine- and amphetamine-regulated transcript (CART) compared with control rats (saline administration). However, there was no significant difference between the heat-treated groups and YH-control and there was no significant difference in neuropeptide Y expression between the heat-treated groups and YH-control. These results suggest that yeast hydrolysate can be use an anti-obesity material after heat treatment.

Effects of Yeast Hydrolysate on Hepatic Lipid Metabolism in High-Fat-Diet-Induced Obese Mice: Yeast Hydrolysate Suppresses Body Fat Accumulation by Attenuating Fatty Acid Synthesis

Aims: We observed whether the anti-obesity activity of yeast hydrolysate (YH) was due to the alteration of lipid-regulating enzyme activities. Methods: Male ICR mice were divided into four groups: a normal diet group (ND; 4.2% fat), a high-fat diet group (HF; 27.7% fat), an HF group treated orally with 0.5% or 1% YH in the drinking water (HF+YH0.5; 27.7% fat and HF+YH1; 27.7% fat). Results: After 5 weeks, the YH groups (HF+YH0.5 = 3.92 ± 0.17 g/100 g BW and HF+YH1 = 3.76 ± 0.13 g/100 g BW) had significantly lower levels of epididymal fats compared to the HF group (4.91 ± 0.29 g/100 g BW; p < 0.05). YH supplementation produced a decrease in serum triglycerides and low-density lipoprotein cholesterol concentrations and body weight gain, and produced a dose-dependent significant increase in serum ghrelin compared with the HF group (p < 0.05). Hepatic glucose-6-phosphate dehydrogenase (G6PD) activity was inhibited by YH supplementation compared with the HF group, and mice treated orally with 1% YH exhibited a significant decrease in hepatic malic enzyme (ME) activity compared to obese mice treated with the vehicle (HF = 10.44 ± 2.74 nmol/min/mg protein vs. HF+YH1 = 6.68 ± 2.23 nmol/min/mg protein; p < 0.05). Conclusions: YH supplementation suppressed body fat accumulation by attenuating fatty acid synthesis through the downregulation of hepatic G6PD and ME activities.

Short Communication: Pet foods with yeast hydrolysate can reduce body weight and increase girth in beagle dogs

Kim, J. H., Jung, E. Y., Hong, Y. H., Bae, S. H., Kim, J. M., Noh, D. O., Nozaki, T., Inoue, T. and Suh, H. J. 2012. Short Communication: Pet foods with yeast hydrolysate can reduce body weight and increase girth in beagle dogs. Can. J. Anim. Sci. 92: 207–210. Beagle dogs fed pet foods that included yeast hydrolysate (YH) were used in the present study to assess the possible use of YH as a functional anti-obesity ingredient in pet food. The change in weight and girth in the YH groups was significantly (P&lt;0.05) lower than that in the control. Plasma malondialdehyde was significantly (P&lt;0.05) lower in the YH groups compared with that in the control. Plasma levels of the reduced form of glutathione were significantly (P&lt;0.05) higher in the YH groups than those in the control. Therefore, YH could be recommended as an anti-obesity functional feed source for dogs.

Improvement of ethanol production from sugarcane molasses through enhanced nutrient supplementation using Saccharomyces cerevisiae

Saccharomyces cerevisiae as a yeast cream was utilized for alcoholic fermentation using sugar cane molasses. In the present study, fermentation was optimized for urea and yeast hydrolysate (YH) dosage and the combined effect was evaluated. Total sugars as inverts (TSAI) composition of molasses were determined by HPLC as 39% (m/v). Urea concentrations of 4, 2 and 3 gl-1 showed optimal ethanol production at 30, 35 and 40°C respectively. A YH concentration of 0.5 gl-1 resulted in an ethanol yield of 8.7% (m/v) with a fermentation efficiency of 85.12%. Under optimized conditions (35°C) significant improvements were noticed with ethanol yield of 7.8% (m/v) and efficiency of 76.3%. Key words: Ethanol, ethanologenic, fermentation, molasses, Saccharomyces cerevisiae.

Medium and feed optimization for fed-batch production of a monoclonal antibody in CHO cells

Background Mammalian cells are used extensively in the production of recombinant proteins, and of monoclonal antibodies (MAbs) in particular. The trend towards avoiding animal-derived components in biopharmaceutical production processes has led to the extensive use of nonanimal origin hydrolysates such as plant hydrolysates or yeast hydrolysates. The source of hydrolysates affects cell growth and productivity and may also affect product quality. Accordingly, careful consideration should be given during process and cell culture media development, in order to determine the appropriate type and amount of hydrolysates to be added, for the cell and product at hand. In this study, we assessed the impact of several hydrolysate additives and chemically defined (CD) commercial feeds on MAb titers, MAb average specific productivity (average Qp), cell viabilities and metabolite profiles in suspension cultures of recombinant CHO cells expressing a monoclonal antibody in shake flasks and 2 L bioreactors.

Methyl eugenol and pre‐release diet improve mating performance of young Bactrocera dorsalis and Bactrocera correcta males

AbstractThe objective of this extensive series of experiments, involving more than 2800 field cage tests with potted mango trees, was to assess pre‐release supplements to enhance the mating success of sterile male Bactrocera dorsalis and Bactrocera correcta. We examined the effects of different pre‐release diets and methyl eugenol (ME), both independently and in combination. Tests were carried out more than 15 and 18 days for B. dorsalis and B. correcta, respectively, each day increasing the age of sterile flies. To evaluate the effect of different pre‐release diets on males, no‐choice mating tests were conducted with sterile males of increasing age and mature sterile females. Sterile males fed up to 2 days of age on sugar–yeast hydrolysate combinations achieved significantly more matings than males fed only water in B. dorsalis and more matings than males fed only sugar, only yeast hydrolysate or only water in B. correcta. To examine the effect of ME on mating performance, 2‐, 3‐, 4‐ or 5‐day‐old sterile males were given or not given access to ME for 1 h, followed by the sugar–protein diet until the day of the mating test. Mating performance tests were carried out with ME‐exposed and non‐exposed sterile males competing with mature wild males for wild females. Results showed a significant mating advantage of ME‐exposed over non‐exposed sterile males, although at younger ages they were still less competitive than wild males. The interaction of sugar–yeast hydrolysate diet and ME as pre‐release treatments for 2‐ and 3‐day‐old sterile males was assessed in terms of male sexual competitiveness. Overall, the combination showed an additive effect on increased mating success in B. dorsalis sterile males when competing a wild males for wild females, while in B. correcta males the drastic improvement in mating success was mainly linked to the ME exposure.

Influence of adult diet and exposure to methyl eugenol in the mating performance of Bactrocera philippinensis

AbstractEnhancement of the sterile male performance in Bactrocera philippinensis through access to protein (yeast hydrolysate) and/or exposure to methyl eugenol (ME) was investigated in this study. The temporal occurrence of sexual maturity of B. philippinensis was determined for both laboratory sterile and wild flies. Laboratory tests were also conducted to determine the peak age of ME feeding in relation to male fly age and sexual maturity and effect of protein on the longevity of sterile males. Field cage mating tests were performed to examine the effect of adult diet (P+ vs. P−) and ME exposure (ME+ vs. ME−) on the mating competitiveness of the sterile male B. philippinensis. P+ME+ sterile male flies achieved significantly more matings with wild females than P+ME− or PE−ME− sterile males. Based on the relative sterile index, P+ sterile male flies were significantly more sexually competitive when competing for wild females than P− flies. The results confirm that the pre‐release diet can be significantly improved to increase the effectiveness of the application of the sterile technique against B. philippinensis.

Sex differences in developmental response to yeast hydrolysate supplements in adult Queensland fruit fly

AbstractPost‐teneral dietary supplements have been found to improve mating performance of male Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) (Q‐fly) and show considerable promise for enhancement of sterile insect technique (SIT) programmes even when applied within the current 48 h pre‐release holding period. However, Q‐flies are released as a bisexual strain, and the positive effects of a diet including yeast hydrolysate for males may also boost reproductive development and sexual performance of females. Increased prevalence of mature sterile females can substantially dilute SIT efficacy as mating capacity of sterile males is largely depleted by sterile females rather than the relatively rare wild females. Here, we demonstrate that providing yeast hydrolysate for 48 h after adult emergence, emulating the current pre‐release holding period of Q‐fly SIT, leads to a significant increase in reproductive development and sexual performance in male Q‐flies. In contrast, female Q‐flies with access to yeast hydrolysate for 48 h had ovaries that were poorly developed and, particularly at younger ages, were less likely to mate and remate than females with continuous, ad libitum access to yeast hydrolysate. Our findings suggest that addition of yeast hydrolysate into the pre‐release diet of Q‐flies could be a cost‐effective means of releasing a bisexual strain with competitive males but with sexually immature females, thereby rendering it operationally more similar to a unisexual strain.

Age‐stage, two‐sex life tables of Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae) with a discussion on the problem of applying female age‐specific life tables to insect populations

Abstract Age‐stage, two‐sex life tables of the melon fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), reared on cucumber (Cucumis sativus L.), sponge gourd (Luffa cylindrica Roem) and a carrot medium (mashed Daucus carota L. mixed with sucrose and yeast hydrolysate) were constructed under laboratory conditions at 25 ± 1°C, 65%± 0.5% relative humidity, and a photoperiod 12 : 12 h (L : D). The intrinsic rates of increase of B. cucurbitae were 0.144 6, 0.141 2 and 0.068 8 days on cucumber, sponge gourd, and carrot medium, respectively. The highest net reproduction rate was 172 offspring per fly reared on sponge gourd. The mean generation times of B. cucurbitae ranged from 34 days reared on cucumber to 56 days reared on carrot medium. The life history raw data was analyzed using the traditional female age‐specific life table and compared to results obtained using the age‐stage, two‐sex life table. When the age‐specific female life table is applied to an age‐stage‐structured two‐sex population, survival and fecundity curves will be improperly manipulated due to an inability to include variation in preadult development time. We discussed different interpretations of the relationship between the net reproductive rate and the intrinsic rate of increase to clarify possible misunderstanding in the literature.

Promotion Effects of Yeast Hydrolysates and a Mixture of Safflower Seed and Gasiogapi Extract on Longitudinal Bone, Proximal Epiphysis, and Growth Hormone in Rats

This study examined the growth effects of yeast hydrolysate (YH) and a traditional Korean herbal mixture (HM, a mixture of safflower seed and gasiogapi extract). Three-week old male SD rats were divided into the following five groups: negative control (saline), positive control (foremilk 0.5 g/㎏/day), YH (YH 0.5 g/㎏/day), HM (HM 0.2 g/㎏/day), and YH＋HM (YH 0.5 g/㎏/day and HM 0.2 g/㎏/day). Tibia bone length was 9.22 ㎜ in the normal control rats, while both the YH and YH＋HM groups had significantly longer tibia bones than the control rats (9.75 ㎜ and 10.46 ㎜, respectively). The proximal epiphyses of YH, HM, and YH＋HM measured 0.75, 0.70, and 0.75 ㎜, respectively, while the length in the control group was 0.50 ㎜. Plasma insulin growth factor-1 (IGF-1) level was slightly higher in the YH group (1.36 ㎎/㎖) than in the control rats (1.29 ㎎/㎖), but the difference was not significant. Plasma IGF-1 level was significantly increased in the HM (1.49 ㎎/㎖) and YH＋HM (1.53 ㎎/㎖) groups compared to the control group (1.29 ㎎/㎖). Growth hormone (GH) levels in YH (17.45 ng/㎖), HM (15.49 ng/㎖), and YH＋HM (16.07 ng/㎖) were significantly different compared to the control group (3.63 ng/㎖).

Post‐teneral nutrition as an influence on reproductive development, sexual performance and longevity of Queensland fruit flies

AbstractAdult Queensland fruit flies, Bactrocera tryoni (Froggatt), require adequate post‐teneral nutrition to complete reproductive development, to perform sexually and for maximum longevity. Recent research has focussed on nutritional requirements of adults released in sterile insect technique (SIT) programmes that are used to manage these pests. Several studies have suggested benefits of providing yeast hydrolysate (YH) in addition to sugar during the 24‐ to 48‐h pre‐release holding period. Current evidence suggests that provision of YH can induce faster development, increased mating probability, longer copulations, increased sperm storage by mates, higher levels of sexual inhibition in mated females and increased longevity. We here review research on adult B. tryoni nutritional requirements, assess the potential application of this information in the context of SIT programmes and highlight future research that will help to determine whether YH, or other supplements, should be included as pre‐release treatment in B. tryoni SIT.

A complete industrial system for economical succinic acid production by Actinobacillus succinogenes

An industrial fermentation system using lignocellulosic hydrolysate, waste yeast hydrolysate, and mixed alkali to achieve high-yield, economical succinic acid production by Actinobacillus succinogenes was developed. Lignocellulosic hydrolysate and waste yeast hydrolysate were used efficiently as carbon sources and nitrogen source instead of the expensive glucose and yeast extract. Moreover, as a novel method for regulating pH mixed alkalis (Mg(OH) 2 and NaOH) were first used to replace the expensive MgCO 3 for succinic acid production. Using the three aforementioned substitutions, the total fermentation cost decreased by 55.9%, and 56.4 g/L succinic acid with yield of 0.73 g/g was obtained, which are almost the same production level as fermentation with glucose, yeast extract and MgCO 3. Therefore, the cheap carbon and nitrogen sources, as well as the mixed alkaline neutralize could be efficiently used instead of expensive composition for industrial succinic acid production.

WEIGHT REDUCTION EFFECTS OF YEAST HYDROLYSATE BELOW 10 kDa ON OBESE YOUNG WOMEN

We investigated the antiobesity effects of yeast hydrolysate below 10 kDa on obese young women for the 4 weeks to assess its possibility as a dietary supplement. Subjects were randomly assigned to the placebo group (n = 10) and yeast hydrolysate below 10 kDa 1 g/day (YH) group (n = 10). The results showed body weight was lost significantly (P < 0.05) in the YH group (1.68 kg) compared with placebo group (0.71 kg). And the percent ideal body weight (PIBW) and body mass index (BMI) of the YH group (PIBW: 3.04%; BMI: 0.65 kg/m2) were decreased significantly (P < 0.05) compared with placebo group (PIBW: 1.26%; BMI: 0.27 kg/m2). The reductions of fat mass, percent body fat, body circumference and skinfold thickness also were slightly higher in the YH group than placebo group, however, the significant effects in these variables were not observed. PRACTICAL APPLICATIONS The limited long-term efficacy of conventional weight management (dietary intervention, physical activity and behavioral therapy) has lead to the development of alternative weight reduction strategies. Alternative therapies such as the use of natural supplements are beginning to form a large and growing market. In order to provide new discoveries and solutions related to natural supplements, we have turned to yeast, a microorganism that mankind has long made use of. The development of dietary supplement using yeast is very valuable for fields related to antiobesity. This report may give useful information about the use of yeast hydrolysate below 10 kDa as a weight-loss supplement.

Sexual development of wild and mass-reared male Queensland fruit flies in response to natural food sources

Diet has a profound influence on the fitness of adult tephritid flies. Mass-reared flies are provided yeast hydrolysate as a rich source of nutrition that supports rapid sexual development and mating success. In contrast, wild tephritid flies often live in environments where food may be hard to find, and these are the conditions that sexually immature mass-reared sterile males encounter when released into the field during sterile insect technique campaigns. The effect of natural food sources (bat guano, bird droppings, citrus pollen, and wheat pollen) on the sexual development of adult mass-reared fertile, mass-reared sterile, and wild male Queensland fruit flies, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), was determined by measuring ejaculatory apodeme size. Inclusion of yeast hydrolysate in the adult diet was associated with faster growth of the ejaculatory apodeme in comparison with all other diets. Effects of diet were far less pronounced in mass-reared males, which may indicate reduced nutritional requirements, whereas the ejaculatory apodeme of wild males fed on natural sources of food or sucrose alone did not increase in size over the first 20 days of adult life.